ABSITE Review

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1 Dissecting the Junior Absite Terra Holdeman, MD, MS

Transcript of ABSITE Review

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Dissecting the

Junior Absite

Terra Holdeman, MD, MS

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Dissecting the Junior Absite Copyright © 2007 Lulu Press Author: Terra C. Holdeman, M.D., M.S. All Rights Reserved. No part of this book may be reproduced in any form without permission in writing from the author. This book is intended for use in the preparation of taking the American Board of Surgery In-Training Examination, and is not meant to be used in the treatment of patients. Readers are encouraged to corroborate with current resources regarding any knowledge used in the treatment of patients.

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Dedication:

To Phil, the love of my life; to my parents, who have supported me every step of the way; and to my God, who has guided my steps, held my hand,

and given me strength for each new day.

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Table of Contents:

Chapter 1: Anatomy...................................... 9

Chapter 2: Anesthesia ................................ 13

Chapter 3: Biostatistics ............................... 17

Chapter 4: Breast ....................................... 19

Chapter 5: Cell Biology............................... 23

Chapter 6: Critical Care .............................. 25

Chapter 7: Endocrinology ........................... 29

Chapter 8: Fluids, Electrolytes, Nutrition..... 35

Chapter 9: Gastrointestinal ......................... 39

Chapter 10: Gynecology............................. 65

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Chapter 11: Head and Neck........................67

Chapter 12: Hematology .............................69

Chapter 13: Neurosurgery...........................73

Chapter 14: Oncology .................................77

Chapter 15: Orthopedics.............................81

Chapter 16: Pediatrics ................................83

Chapter 17: Pharmacology .........................87

Chapter 18: Skin/Soft Tissue ......................91

Chapter 19: Thoracic ..................................95

Chapter 20: Thyroid/Parathyroid ...............105

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Chapter 21: Transplant/Immunology ........ 109

7 Chapter 22: Trauma ................................. 115

Chapter 23: Urology ................................. 119

Chapter 24: Vascular................................ 125

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ANATOMY Arteries: SMA: crosses at 3rd/4th jxn of duodenum IMA superior rectal artery, sigmoid arteries, L colic artery Internal iliac artery middle rectal artery Internal pudendal artery inferior rectal artery Celiac axis: leads to left gastric artery, splenic artery, common hepatic artery Internal mammary artery: first branch off subclavian arter Proper hepatic artery: leads to right gastric artery Hepatic artery variants: • R hepatic artery: off SMA • L hepatic artery: off L gastric artery Right renal vein: anterior to artery Ant to post neck: subclavian vein phrenic nerve

ant scalene subclavian artery Blood supply to stomach s/p esophagetomy: right gastroepiploic artery Blood supply to the head of the pancreas: SMA and celiac trunk Blood supply to CBD: cystic and post pancreaticoduodenal ateries Blood supply to parathyroid: inferior thyroid artery

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Veins: Portal vein: branches into L gastric vein, splenic vein, IMV, SMV SMV: behind neck of pancreas L gonadal vein: drains to L renal vein R gonadal vein: drains to IVC Nerves: Superior laryngeal nerve: innervates cricothyroid, loss of pitch if injured Recurrent laryngeal nerve: innervates all larynx except cricothyroid, hoarse if injured Post-op bilateral vocal cord paralysis Tx: temporary trach Post-op chronic hoarseness Tx: medialization of vocal cords R recurrent laryngeal nerve: lateral, wraps around innominate artery L recurrent laryngeal nerve: wraps around aorta 2nd intercostal nerve intercostal brachial nerve

medial arm sensation; can cut it Intercostal brachiocutaneous nerve: axillary numbness, most common injury

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Long thoracic nerve (post to middle scalene) serratus anterior winged scapula ThoracoDORsal nerve latissimus DORsi weak pull-ups and arm adduction Medial pectoral nerve both pecs Lateral pectoral nerve pec minor only Cricopharyngeus (UES) sensory innervation: from glossopharyngeal (CN9) Cricopharyngeus (UES) motor innervation: from vagus (CN10) Ileoinguinal nerve: thigh/scrotum sensation, cremasteric reflex, runs on spermatic cord Genitofemoral nerve: thigh/scrotum sensation, cremasteric reflex, traverses inguinal canal Hypoglossal nerve: tounge moves to side of injury Glossopharyngeal nerve carotid body vagus and phrenic nerves Common peroneal nerve: foot drop External sphincter innervation: internal pudendal nerve (S2-S4) Fascial sheath posterior to rectus abdominus: transversalis fascia Liver segments near GB: (lateral = segment 5), (medial = segment 4)

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Femoral hernia: (LATERAL border = femoral vein); (Medial border = lacunar ligament)

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ANESTHESIA ↓MAC: more lipid soluble, more potent, long induction Face/neck: last to recover, first to relax (Diaphragm: 1st muscle to recover) Local anesthetic toxicity: perioral numbness/twitch

tinnitus seizures V Fib Local anesthetic efficacy: do not work in acidic (infected) environments Sucessful endotracheal intubation: chest movement, end tidal CO2 Absent breath sounds after abd insufflation/ Trendelenburg: R mainstem intubation US: ↑MHz ↑penetration Most common cause of anaphylaxis: muscle relaxants Epidural: ∆MS, resp depression (due to morphine), hypoTN/↓HR (due to bupivicaine) No epidural: if pt has hypertrophic cardiomyopathy Spinal headache Tx: blood patch Drugs: Malignant hyperthermia: Ca release from SR => ↑end tidal CO2, high K (Tx: Dantrolene)

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Non-depolarizing paralytics: competitive inhibitor of ACh receptor (OD Tx: Neostigmine) Amides: have “i” in first part of name Esters: allergies due to PABA (Ex: tetracaine) Amrinone: PDE inhibitor, activates cAMP, ↑CO, ↓SVR Ativan OD Tx: Flumazenil Atracurium: predictable in vivo drug clearance “Hoffman degradation” Bupivicaine: toxic >175mg, MCC of epidural hypotension/bradycardia Fentanyl: fat soluble (OD Tx: Narcan) Halothane: hepatotoxic Isoproterenol: ↑HR Ketamine: ↑cardiac work, severe hallucinations, no resp depression, OK to use with hypotension Lidocaine: toxic >300mg CNS sx (Tx: BZ) V Fib, cardiac arrest (↑action potential threshold)

• Max Dose: 5mg/kg • Max Dose w/ Epi: 7mg/kg

Methoxyfluorane: renal toxicity Morphine: MCC epidural resp depression, histamine release (except in CSF: no mast cells) Nitric oxide: ↑MAC

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Pancuronium: causes tachycardia “like getting hit with a pan”, used in lethal injections Procaine “Novocaine”: MCC allergic reaction Propofol: hypnotic Protamine: hypotension if given too quickly Succinylcholine: only depolarizing agent, glaucoma, releases K (not w/ RF)

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BIOSTATISTICS US Killers: #1:CAD, #2:Cancer Mean: average Median: 50th percentile Mode: most frequent value Sensitivity: good for screening “SpIn: positive test rules it in” Specificity: good for specific dz “SnOUT: negative test rules it out” Values related to patient: PPV, NPV Values related to test: sensitivity, specificity Prevalence: total diseased Incidence: new cases Chi2: compare percentages T-test: compare 2 means ANOVA: t-test for >2 samples Null hypothesis: no difference exists

• Type I error: rejects null hypothesis incorrectly • Type II error: accepts null hypothesis incorrectly

due to low sample size Power: 1-prob of type II error, prob of making a right conclusion, ↑by ↑sample size Prospective cohort: Non-random

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NSQIP study: risk adjusted M & M based on severity of pt illness

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BREAST Types: Breast CA Risk Factor: age (menarche, 1st child), 1st degree relatives, # bx, atypical hyperplasia Mastodynia (breast pain) Tx: Danazol, OCs, Tamoxifen, evening primrose oil Comedocarcinoma Tx: simple mastectomy, poor prognosis Cystosarcoma Phylloides Tx: wide local excision only (no LND), hematogenous spread DCIS (CA precursor) Tx: Lumpectomy and radiation (50% become invasive CA) LCIS (marker of risk) Tx: mastectomy vs tamoxifen vs observe (35% become CA in either breast) Fibroadenoma: most common breast tumor in young females (<35 y/o) Fibrocystic disease: atypical hyperplasia increases CA risk 4x (Tx: excisional bx) Inflammatory breast CA: infiltrates LN, pulls Cooper’s ligaments, peau d’orange Inflammatory breast CA Tx: chemotherapy mastectomy radiation Intraductal Papilloma: bloody nipple discharge, no risk of CA (Tx: duct excision) Paget’s dz of nipple: crusty nipple underlying DCIS

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Male breast CA: BRCA-2, ER (+), usually DCIS (Risk factors: Klinefelters, steroids, XRT) Teenage boy gynecomastia: observe for one year Lymph Nodes: Level 1 nodes: lateral to pec minor Level 2 nodes: beneath pec minor Level 3 nodes: medial to pec minor LND borders: superior=axillary vein, inferior=breast fat, medial=pecs, lateral=lat dorsi LND: blue nodes + highest gamma count + nodes within 10% of highest gamma count LN Bx contraindications: palpable nodes, multicentric, pregnant, neoadjuvent therapy Positive LN with no known primary Tx: mastectomy Breast CA: staging based on node status Genetics: PR(+) tumors: better prognosis than ER(+) tumors Bad prognosis: erb-2, p53, cathepsin, Her2-neu Her2-neu Tx: Herceptin BRCA-I (AD): assoc w/ ovarian CA (40%) BRCA-II (AD): assoc w/ male breast CA (10%)

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BRCA + Fam Hx: 60% risk of breast CA Prophylatic mastectomy: ↓risk by 90% Treatment: Tamoxifen: estrogen agonist, dose=20mg/day x 5yr Tamoxifen: ↓breast CA (50%), ↑endometrial CA(0.1%) and DVT risk (1%) Arimidex: counteracts risk of endometrial CA and DVTs associated with Tamoxifen use Post-mastectomy radiation: >4LN, positive margins, skin or chest wall involvement Radiation contraindications: SLE, RA, scleroderma, pregnancy, previous radiation FNA: can’t tell tumor vs CA or if invasive Syndromes: Mondor’s dz: thrombophlebitis of superificial vein of breast, cord-mass lateral (Tx: NSAID) Batson’s plexus: valveless vertebral veins that allow breast CA mets to spine Poland syndrome: no breasts/pectoralis, hypoplastic shoulder Stewart Treves: lymphangiosarcoma = purple arm mass 10yrs post-LND

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Staging: BI-Rads: • 0: need more imaging • 1: nothing there • 2: benign mammogram q1yr • 3: prob benign mammogram q6mo • 4: suspicious do bx • 5: very suspicious do bx Breast CA staging (TNM): 1cm tumor = 5yrs old • T2: 2-5cm • T4: skin or chest wall involvement (peau

d’orange) • N1: movable axillary nodes (Tx: chemo) • N2: fixed axillary nodes • N3: internal mammary nodes • M1: supraclavicular mets Staging Ultra-simplified: yes, of course, there is much more to it – but start with this… • Stage I: T1 • Stage IIa: T2 • Stage IIb: T3 • Stage IIIa: N2 • Stage IIIb: N3 • Stage IV: M1

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CELL BIOLOGY Cell Cycle: • G0: do nothing • G1: makes all proteins for DNA synthesis

most variable, GF acts here • S: synthesis • G2: make all proteins for mitosis • M: mitosis sensitive to radiation here Transcription: DNA RNA mRNA (occurs in nucleus) Translation: mRNA + tRNA protein (occurs in cytoplasm) N-terminal: active part of hormone Steroids: bind in cytoplasm go to nucleus affect protein transcription Kreb: 38 ATP (anaerobic glycolysis 2 ATP and lactate) Kreb (in liver): lactate + pyruvate glucose Cori cycle (in liver): glucose lactate glucose Branched aa (Leu, Ile, Val): metabolized in muscle Mitochondria: TCA cycle in inner matrix Nucleus: outer membrane = rough ER Nucleolus: no membrane, ribosomes made here Rough ER: makes proteins for export Smooth ER: makes cytoplasmic proteins

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Lymphatics: no BM, loose cell-cell jxn; none in brain, muscle, tendon, bone

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CRITICAL CARE Normal Values: • Cardiac Index: 2.2-4.2 • SVR: 800-1200 • Wedge pressure: 6-12 • CVP: 5-9 (higher means hydrated) Shock: • Septic (nl:4-8): ↑CI • Hypovolemic (nl:11): ↓PCWP = preload, ↑SVR • Cardiac: ↑PCWP • Neurogenic: ↓all ↑mixed venous O2 sat (tissue is not picking O2 up): septic shock, cirrhosis, LtoR cardiac shunt ↓mixed venous O2 sat (low O2 delivery): MI, cardiac tamponade, hemorrhagic shock Pt on TPN w/ acute hyperglycemia: infection Peds bolus: 20cc/kg LR repeat 10cc/kg PRBC Child maintanence IVF: 4/2/1 for each 10kg Catecholamine response to injury: max at 24 hrs Post-trauma: aa + lactate liver glucose EDRF=NO: made from Arg in endothelial cells, vasodilates, higher in sepsis Sepsis: resp alkalosis

• 1st 24hr: high glucose • Late: SVO2 > 77% (low O2 extraction)

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Sepsis: activates Prot C fibrinolysis Sepsis Tx: activated Protein C “Xigris”, causes fibrinolysis Burns: highest energy requirement Burn pt CO: initial drop, then hyperdynamic Burn pt: rapid changes in Na Burn Calorie needs: 25 kcal/kg/day + (30kcal x %burn) Burn Protein needs: 1g/kg/day + (3g x %burn) Inhalation burn injury: due to smoke and carbon, not heat Burn sepsis: due to Psuedomonas Burn wound infxn: peripheral edema, scars, green, black skin, eschar separation Burn wound infxn: >105 organisms, bx to diagnose, HSV common Burn pt #1 infection: pneumonia Circumferential burns w/ ↓perfusion Tx: escharotomy, then fasciotomy if needed Chest burn w/ ↑CO2 and ↑airway pressure Tx: escharotomy Burn pt + succinylcholine: ↑K High K Tx:

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1) Ca gluconate 2) Insulin/glucose 3) Bicarb 4) Kayexalate HF Burn Tx: topical calcium Silvadene: works well against Candida, not penetrate eschar, risk of neutropenia Sulfamyelon “Mafenide acetate”: painful, carbonic anhydrase inhibition, ↑Cl metabolic acidosis Silver nitrate: ↓NaCl, MetHb

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ENDOCRINOLOGY Parietal cells: make H+/IF, bind Vit B12, absorbed in terminal ileum Histamine/PPI Chief cells: make pepsinogen for proteolysis Satiety hormones: DA, SS Hunger hormones: ghrelin, CCK Hormones: ADH: water absorption in DCT, vasoconstriction, don’t pee “hold onto everything you got” ↑ADH: Caused by ↑PEEP, inhalational anesthetics, opiods, surgical stress Aldosterone: resorbs Na, secretes H/K in CD ANP: vasodilator, released by cardiac stretch, removes excess CHF volume “let it all go” CCK (from gut mucosa): GB contrac, relax Oddi, release digestive enzymes from pancreas Enteroglucagon: SB hyptertrophy Enterokinase (duodenum): most potent activator of trypsinogen Gastrin (from G cells): stimulates parietal and chief cells “go, go, go!” How do you suppress gastrin? gastrin, H+

Gastrinoma: secretin stimulation test: ↑gastrin >200 => ZE; localization via intraop endoscopy

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Gastrinoma: #1 islet cell tumor in MEN, panc head mass + stomach ulcer + diarrhea Sporadic Gastrinoma: occurs at jxn of pancreatic head and duodenum (Tx: excise) Glucagon (from pancreas α cells): gluconeogenesis Glucagonoma: glossitis, stomatitis, migratory necrolytic erythema (red skin lesions) Insulinoma: #1 islet cell tumor, high C-peptide; localization via intraop endoscopy (Tx: enucleate) Motilin: makes MMC cleans stomach/gut of debris q90 min Erythromycin works here • Phase I: Quiescence • Phase II: Acceleration/GB contraction • Phase III: Peristalsis • Phase IV: Deceleration Peptide YY (from terminal ileum): inhibits H+ secretion after meal Secretin: controls SB digestion, ↑bile flow, inhibits gastrin/HCl, exocrine pancreatic secretion SS (D cells): slows pancreatic/biliary output, inhibits secretin/motilin/CCK “slows stuff” SS receptor scintigraphy: test for Zollinger-Ellison syndrome SSoma: constipation, steatorrhea, DM, pancreatitis, gallstones Substance P:colon neurotransmitter

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VIP: inhibits secretin/motilin/CCK like SS VIPoma: watery diarrhea, low K; found in 1) pancreas or 2) adrenals/retroperitoneum (Tx: resect) Tests: High dose dexamethasone suppression test Cushing's syndrome • Suppresses: Pituitary tumor (high ACTH)

Cushing's dz • Not suppress:

o Adrenal tumor (high cortisol) o Lung tumor – small cell lung CA (high

ACTH) Pathology: Addison’s: due to autoimmune destruction or withdrawal of steroids Addison labs: ↓Na, ↑K, ↓cortisol/Aldo, sepsis (Tx: steroids) Addisonian crisis “adrenal shock”: hypotension with ↓Na, ↑K Adrenal insufficiency: corticotrophin stimulation test most sensitive Adrenal Mass: • 4-6cm: do CT q3mo • >6cm: remove en bloc

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Congential Adrenal Hyperplasia: ↓21-OHase def, ↓BP, salt wasting (low Na) Conn’s: adrenal tumor: ↑Aldo, ↓K (weak muscles), ↑Na, HTN, ↓renin “Conn’s has low K” Type 1 DM: anti-islet cell Ab, thin, DKA, polyuria/polydipsia/polyphagia Type 2 DM: insulin receptor insensitivity, obese, HONK, acanthosis nigricans, found in twins Diabetes Insipidus: caused by EtOH/head injury, inhibits ADH release, pee a lot (Tx: DDAVP) • Water deprivation: does not conc urine => DI • DDAVP: concentrates urine >25% => central DI Nelson syndrome: after adrenalectomy, hyperpigmentation from β-MSH, vision changes Pheo: R side, 24-hr urine VMA Child Pheo: benign, bilateral, extra-adrenal Extra-adrenal Pheo: MIBG scan, usually in Organ of Zuckerkandl at aortic bifurcation, malignant Malignant Pheo: diagnosis by seeing adjacent structure invasion Pheo preo-op BP control: 1) Phenoxybenzamine (α-blocker), 2) β-blocker, 3) Steroids If give Pheo β-blocker first: HTN crisis Remove Pheo: immediate ↓BP due to inadequate pre-op volume resuscitation (Tx: NE)

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SIADH: ↑ADH, oliguria, ↑urine osmolality, pee Na (Tx: Demecocycline) Thymomas: cut ‘em out Water intoxication: depression in rate of Na decline

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FLUIDS/ELECTROLYTES/NUTRITION 6.25g protein: contains 1g Nitrogen Resting Energy Requirement: 1600 kcal • Fat: 9 kcal/g (need 30% fat calories) • Protein: 4 kcal/g (need 1g/kg/day) • Dextrose/Carbs: 3.4 kcal/g (rest of calories) RQ: CO2 produced/O2 consumed • >1.0: overfeeding • 1.0: Carb • 0.8: Protein • 0.7: Fat • <0.7: starvation TBW: infant (80%) > men (60%) > women (50%) > obese (10% less b/c less water in fat) Water distribution (TBW=60%): cellular (40%) > interstitial (15%) > intravascular (5%) Na deficit: 0.6(kg)(140-Na), replace at 0.5mEq/hr Anion Gap (nl<12): Na – (HCO3 + Cl) NS: NaCl=154 mEq (has less third spacing) LR: Na=130, Cl=109, K=4, Ca=2.7, Bicarb=28 (use with trauma pts) Brain fuel: Glucose (ketones when starving) Kidney fuel: Glucose

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Muscle fuel: Glucose Small bowel fuel: Glutamine (immune cells need it; ppt in TPN); most abundant aa in tissue Colon fuel: Short-chain FA “butyrate” Cancer cell fuel: Glutamine Carb digestion: amylase from saliva (mouth) Protein digestion: pepsin from chief cells (stomach) Fat digestion: lipase (small intestine)

• Micelles enterocytes • Short/Med chain TG/ carbs/ aa portal system • Long chain FA CM lymphatics

(LIJ/Subclavian jxn) Starvation fuel sources: • 72hr: liver => glucose • 1wk: muscle => glucose • Late: fat => ketones Pre-albumin: t1/2=2days Albumin: < 2.5 mg/dL = bad (t1/2=21days) TPN: has Cr, Cu, Se, Zn (add Fe, Zn if TPN >2wk) TPN rate: 5cc/kg/hr to avoid hypoglycemia and high CO2 TPN glucose rate: 5-6g/kg/hr

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TPN infection: Staph epidermidus Nutrition Needs of Organ Failure: • Renal failure: limit protein • Liver failure: branched aa to ↓encephalopathy • Pulmonary failure: low carbs • Heart failure: IVF/salt restriction • Neuro injury: low glucose Cr deficiency: DM, neuropathy Cu deficiency: anemia, neutropenia Mg deficiency: causes low Ca => Chvostek sign (tapping facial nerve causes facial contractions) Mg deficiency: inhibits PTH (replace this if can’t get Ca corrected), causes refractory hypoK Ph deficiency: resp weakness, encephalopathy (need for ATP) Zn deficiency: perioral rash, taste changes, hair loss, poor healing Vit A: reverses effects of steroids on wound healing, ↑Vit C stores, absorb via enterohepatic circ Vit D: skin liver (25-OH) kidney (1-OH) Vit D: increases Ca absorption in intestine by increasing Ca-binding protein Refeeding syndrome: Low Phos, K, Mg start feeding at low rate after long starvation

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Overfeeding: high carbs, high CO2 lead to prolonged intubation Alkalosis: causes low K (drives K into cells and urine) High glucose: causes low Na Highest K conc (peaKed T wave): Saliva > stomach > pancreas/duodenum Which electrolyte should be replaced first: Mg Glutamine: increases immune system Glycogen: depleted 24h after starvation, stays in muscle Linoleic acid: change in vision, hair loss, dermatitis

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GASTROINTESTINAL Esophagus: Strongest layer of esophagus: mucosa (no serosa) Strongest layer of small bowel: submucosa Esophagus muscle: • Upper = skeletal muscle • Lower = smooth muscle UES: 15cm from incisors, rest pressure=70 mmHg, swallow pressure=15 mmHg LES: 40cm from incisors, rest pressure=15 mmHg, swallow pressure= 0 mmHg Cricopharyngeus: most common site of EGD perforation LES: decussating fibers of diaphragm, circular fibers of low esophagus, cardiac notch Swallow: soft palate closes nasopharynx larynx up UES relax pharyngeal contraction Caustic esophageal injuries: NG, endoscopy (don’t neutralize it, no charcoal) • Alakali (Drano): worse, liquefication necrosis,

↑cancer risk • Acid: coagulation necrosis Foreign body aspiration Tx: right angle rigid bronchoscopy

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Most specific GERD Test: 24-hr pH study Antireflux surgery: • Normal manometry: 360˚ Nissen • <30 mmHg peristalsis: 270˚ Belsey (through

chest) • Lap (270˚ Toupet) contraindications: COPD,

bleeding, pregancy • Collis gastroplasty: lengthens esophagus MCC post-Nissen dysphagia: wrap too tight Hiatal Hernias: • Type 1: sliding, at G-E jxn (Tx: observe) • Type 2: paraesophageal, risk of gastric volvulus

(Tx: Nissen due to risk of incarceration) • Type 3: sliding paraesophageal • Type 4: entire stomach + another organ Esophageal spasm: corkscrew barium swallow, ↑LES pressure, ↑peristalsis (Tx: NGN, CCB) Achalasia: high LES pressure, low peristalsis, bird’s beak swallow (Tx: Heller myotomy) Pseudoachalasia: tumor of distal esophagus Scleroderma: low LES pressure, low peristalsis Boerhaave’s: vomit, then chest pain, 85% dead at 24hr, Hartmann’s crunching sign

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Most sensitive test for Boerhaave's: gastrograffin followed by thin barium swallow Most common location of Boerhaave's: left posterior lower esophagus at level of T8 Boerhaave's Tx: Left thoracotomy, then myotomy (mucosal injury > muscle injury) Zencker’s: ↑pressure in Killian’s triangle (Tx: cricopharyngeal myotomy w/ L cervical cut) Plummer-Vinson: upper esophageal webs, spoon nails, Fe-def anemia Schatzki’s ring: lower esophageal webs, dysphagia after swallowing Mallory-Weiss: LES torn mucosa due to vomiting (Tx: EGD – oversew bleeding vessel) Esophageal varices Tx: Sclerotherapy=Na morrhuate, Na tetradecyl sulfate Esophageal varices former Tx: Sengstaken-Blakemore tube Barretts: H+ squamous TALL COLUMNAR adenoCA, p53, ↑risk (50x) of adenoCA High grade dysplasia Tx: esophagectomy Esophageal CA risk factors: chemical ingestion, achalasia Upper esophageal CA: squamous cell carcinoma

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Lower esophageal CA: adenocarcinoma most common Esophageal Leiomyoma Tx: submucosal enucleation via thoractomy, no bx (scar tissue forms) Surgical Approach: • Cricopharyngeus: Left (Ex: Zenckers) • Upper Thorax: Right (Ex: Ivor-Lewis

esophagectomy) • Lower Thorax: Left (Ex: Boerhaave’s) Ivor Lewis Esophagectomy: abd + R thoracotomy, esophagus-stomach in thorax Suguira procedure: esophagogastric devascularization + esoph transection + splenectomy Early perforated esophagus Tx: primary repair, mediastinal drainage, NG Late perforated esophagus Tx: IVF, NPO, Abx Esophagectomy tiny leak Tx: repair, then reinforce with muscle flap or pericardial fat Esophagectomy necrosis Tx: resect, then esophagostomy; reconnect using colon after 3mo

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Gallbladder: Bile pigment: from Hb Bile: 80% bile salts, 15% lecithin, 5% cholesterol. Stones form if ↑chol or ↓salt/lecithin 1˚ Bile acid: cholic acid, chenodeoxycholic acid 2˚ Bile acid: lithocholic acid, deoxycholic acid – formed by intestinal bacteria Conjugated bile salts: absorbed, water soluble GB resorbs NaCl to conc bile: 5g bile pool, recirculated q4h, lose 10% daily Why do you lose <5% bile salt in stool? Hepatic recirculation Gallstones: • Cholesterol (radiolucent): terminal ileum rsxn,

Chron’s, E2, DM, TPN – most common in US • Black (Ca bilirubinate in GB): cirrhosis,

hemolysis, Chron’s, terminal ileum resection • Brown (Ca bilirubinate in CBD): infection, Asian Choledochal cyst (caused by reflux of pancreas enzymes into GB) • Type 1: CBD dilitation (Tx: resect +

hepaticojejunostomy) • Type 2: CBD diverticulum (Tx: resect)

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• Type 3: Sphincter of Oddi dilatation (Tx: resect + choledochojejunostomy)

• Type 4: Intra/extrahepatic cysts (Tx: resect, liver transplant)

• Type 5: Intrahepatic cysts "Caroli dz" (Tx: resect, liver transplant)

Mirizzi’s syndrome: CBD obstruction by gallstone

• Type I: compression of hepatic duct • Type II: erosion into hepatic duct

GB symptoms w/ normal US: do HIDA for biliary dyskinesia GB Dyskinesia: HIDA EF<35%, ↑resting basal sphincter tone (Tx: chole) Cholangitis: jaundice, RUQ pain, fever, hypotension, ∆mental status (Tx: abx, sphincterotomy) Cholangitis bugs: E coli, Klebsiella Most common cause of cholangitis: gallstones Pneumobilia: GB-terminal ileum fistula due to gallstone (Tx: remove stone, leave GB/fistula) Hemobilia: jaundice, RUQ pain, GI bleed. Fistula b/w CBD/hepatic artery

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GB polyp Tx: resect if >1cm Gallbladder tumor <10mm Tx: observation GB adenocarcinoma Tx: remove GB (and basin w/2cm margins if through muscularis) Klastskin tumor: bile duct CA w/ conj hyperbilirubinemia with non-dilated ducts Lap Chole: causes benign biliary stricture, resp acidosis (Tx: ↑RR) Lap Chole: high end tidal CO2 evacuate CO2 from abdomen, L lateral Trendelenburg Lap Chole Shock: • <24hrs: clip falls off cystic artery hemorrhagic

shock (Tx: ERCP sphincterotomy + stent) • Late: ligated CBD cholangitis septic shock

o Ligated CBD Tx: PTC tube (perc trans-hepatic cholangiography)

o Normal CBD Tx: ERCP sphincterotomy + percutaneous drainage

Ligated Hepatic Duct Tx: hepaticojejunostomy CBD Dissection Tx: Roux-en-Y hepaticojejunostomy Cystic Duct Leak: subhepatic fluid after chole (Tx: CT-guided drainage + ERCP) Most sensitive test for cholecystitis: US

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Abd pain + apprehension after biliary procedure: due to dilated stomach Biliary obstruction: causes decreased absorption of fat-soluble Vit K ↑INR Hernia: Inguinal hernia: preserve genitofemoral nerve

• Most common complication: urinary retention

• Most common recurrence location: medial part of mesh

• Most common injured nerve: genitofemoral nerve thigh/scrotum numbness

Femoral hernia: medial to vein, occurs in old ladies, need to operate

• If can’t reduce bowel through inguinal incision: cut inguinal ligament, then repair

Spigelian hernia: along semilunar line, through linea semilunaris Grynfelt’s hernia: superior lumbar triangle Petit’s hernia: inferior lumbar triangle Littre hernia: Meckel’s diverticulum hernia Richter hernia: partial bowel wall hernia Amyand hernia: inguinal hernia involving appendix

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Oburator hernia: Howship-Romberg sign, pain w/ internal rotation of thigh, females Incarcerated hernia: dilated SB, bilious emesis Incarcerated inguinal hernia Tx: resect through groin incision Incarcerated umbilical hernia Tx: repeat hernia + peritoneovenous shunt Sliding hernia in females: contains ovaries Sliding hernia in males: contains cecum Leaking ascites through periumbilical hernia: IV abx, diuresis, fix hernia in several days Small/Large Intestines: Most sensitive test for GI bleeds: tagged RBC scan Vasopressin: tx GI bleeds, low splanchnic/portal flow. Use β-blocker to avoid angina Ace of spades x-ray: sigmoid volvulus Thumbprint x-ray: toxic megacolon Barium clumping x-ray: celiac sprue Abrupt cut-off x-ray: volvulus

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Corkscrew x-ray: esophageal spasm Apple core x-ray: cancer Stacked coin x-ray: intussussception String sign x-ray: pyloric stenosis Bird’s beak x-ray: achalasia Most common fecal bacteria: bacteriodes vulgaris Campylobacter colitis: see apthous ulcers on colonoscopy Intra-abdominal abscess locations: pelvic, sub-diaphragmatic, sub-hepatic, inter-loop Clean cases: groin vessels, open heart, prosthetics (Tx: 1g Cefazolin or 1g Vanc) Clean-contaminated cases: abdomen, gallbladder (Tx: 1g Cefazolin or 1g Vanc) Contaminated cases: colorectal, appendectomy (Tx: 2g Cefoxitin or 600mg Clindamycin) Enteric fistula: non-anion gap metabolic acidosis Non-healing fistula: IBD, foreign body, rad, epithelization, neoplasm, distal obst, sepsis TPN: increases closure rate of fistula

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Colonocyte energy: short chain FA Colon secretes: K and HCO3 Jejunum: absorbs most stuff including water (iron goes to duodenum, vitamins go to ileum) Enterochromaffin cells: secrete serotonin, stains argentaffin Interstitial cells of Cajal: “intestinal pacemakers” Visceral sensation: A-delta and C-unmyelinated fibers Adult intussussception: from cecal CA PSBO: 65% cured with NG SBO: proximal obstructions causes more severe abd cramps Ogilvies: pseudo-obstruction, postop ileus w/ 10 cm cecum (Tx: Neostigmine/ colonoscopy) Sigmoid volvulus: decompress with sigmoidoscopy, do sigmoidectomy if peritoneal signs Recurrent sigmoid volvulus: endoscopic nucleation elective sigmoidectomy Cecal volvulus: do right hemicolectomy Colon AV malformation: ¼ have aortic stenosis, ½ have CAD Duodenal ulcers: anterior perforate, posterior bleed (GDA)

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Ulcerative Colitis: bloody diarrhea, lead pipe colon, sclerosing cholangitis, toxic megacolon UC proctocolectomy: helps skin/anemia/arthritis; NOT help sclerosing cholangitis Chron’s: granulomas, skip lesions, creeping fat, fistulas, oxalate stones, involves anus Chrons fistula Tx: Remicaide Chron's with multiple strictures: no resection (Tx: strictureoplasty) Chron’s with duodenal obstruction Tx: gastrojejunostomy Pouchitis Tx: Flagyl or short-chain FA enema Pyoderma Gangrenosum: skin ulcer assoc w/ IBD (Tx: Dapsone, steroids) HLAB-27: Psoriasis, Ankylosing spondylosis, IBD, Reiters, Sacroilitis “PAIRS” Carcinoid: Trp 5-HT 5-HIAA pellagra (diarrhea, dermatitis, dementia) Recurrent carcinoid test: octreotide scan Carcinoid syndrome (liver mets): flushing/diarrhea (5-HT), R heart lesion (Tx: Ocretotide) Carcinoid sites: appendix > ileum > rectum "AIR" Carcinoid of appendix (most common): Appy or R hemicolectomy if >2cm or involves base

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Carcinoid chemo (palliative): 5-FU, Streptozocin Lap Appy: Find normal appendix + Chron’s do appy (unless cecum is inflamed) Lap Appy: Find normal appendix + terminal ileitis do appy (unless cecum involved, leak risk) Incindental Meckel’s: leave it alone Pringle maneuver: int. clamp of portal triad to control liver bleed (not hepatic veins) “pinch ‘em” Kocher maneuver: examine duodenum, panc head, and portal triad Strongest layer of bowel anastamosis: submucosa Weakest time of hand-sewn bowel anastamosis: 3-5 days Short gut syndrome: can’t absorb enough nutrients to be off TPN Short gut syndrome: need 50cm w/ileo-cecal valve OR 75cm without ileo-cecal valve Roux en Y: less marginal ulcers than Bilroth (Tx: omeprazole) Tx for all leaks >7 days post-op: perc drain, then full repair at 6-8wk

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Pre-op ileostomy takedown: barium enema to avoid stricture Terminal ileum resection:

• ↓bile salt uptake diarrhea • ↓fat uptake steatorrhea • ↓B12/IF megaloblastic anemia • ↓oxalate binding kidney stones

Time from polyp to cancer: 8 yrs Familial Colon Cancer (AD): • FAP: APC gene, distal, left-side tumors, total

colectomy at 20y/o, desmoids ↓life expectancy o Duodenum polyp tx: Sulindac o MCC death after total colectomy:

duodenal CA • HNPCC: mismatch repair gene, proximal, right-

side tumors, microsatellite testing o Lynch I: right-side colon CA (“non-

polyposis FAP”), DNA mismatch repair gene

o Lynch II: also ovary, endometrial, stomach, bladder CA

Amsterdam criteria: Three 1st degree relatives over 2 generations

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Gardner’s syndrome: colon CA + desmoid bone tumors Turcot’s syndrome: colon CA + brain tumors Peutz-Jegher: polyps (no colon CA), breast/ovary CA, dark gums/vagina Muir-Torre syndrome: HNPCC with sebaceous gland tumors Villous polyps: malignant MC Duodenum CA: Adenocarcinoma (Tx: Whipple) MC Jejunum CA: Leiomyosarcoma MC Ileum CA: Lymphoma Most common location of colon CA: sigmoid colon Colon CA w/ mets to liver: 30% 5-yr survival rate with resection Recurrent colon cancer s/p LAR: abdominoperineal resection (APR) Colorectal CA Staging (TNM): • T1: into submucosa – may transect rectal CA

transanally • T2: into muscularis propria • T3: into serosa • T4: into adjacent structures • N2: >4 nodes Colorectal CA Staging Simplified:

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o Stage I: T1-2 o Stage II: T3-4 o Stage III: N1 o Stage IV: M1

Liver: Best liver function test: PT Kupffer cells: liver macrophages HMG Co-A reductase: cholesterol rate limiting step in liver Alkaline Phosphatase: made by bone, liver, placenta Child-Pugh classification: • Lab: albumin, PT, bilirubin • Clinical: neuro sx, ascites Portal system: no valves Portal triad: Post=portal vein, Lateral=CBD, Medial=Hepatic artery Cause of air in portal vein: dead bowel or gallbladder fistula Portal HTN: • Pre-sinusoidal: schistosomiasis • Sinusoidal: cirrhosis • Post-sinusoidal: Budd-Chiari

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TIPS: stent connects portal vein to hepatic vein due increased pressure in portal vein Most common side effect of TIPS: encephalopathy Reason you can embolize liver: blood supply from hepatic artery Hepatic abscess (usually right lobe):

• E. coli (from biliary tract infxn): multiple liver abscesses (Tx: Drainage + Imipenem-Cilastatin)

• Entamoeba Histolytica (Mexico): anchovy paste, multiple liver abscesses (Tx: Metronidazole)

• Candida: Drainage + Amphotericin B • Schistosoma: stool ova, portal HTN (Tx:

Praziquantel) • Echinococcus (dogs): hydatid cyst, + Casoni test

(Tx: Albendazole resect ) Post-partum Budd-Chiari (hepatic vein thrombosis) Dx: mesenteric angiogram Caroli’s disease: cystic dilitation of intrahepatic bile ducts Kasabach Merritt syndrome: CHF/DIC due to hemangioma Hepatorenal syndrome: low urine Na Hepatic adenoma: oral contraceptive hx, 10% rupture/bleed

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Hepatic adenoma: cold on sulfur colloid scan (no Kupffer cells) Tx: resect due to bleeding risk Hepatic adenoma with central scar: focal nodular hyperplasia (Tx: observe) Hepatic hemangioma: see filling of lesion during venous phase on CT scan (Tx: observe) Hepatic hemangioma: peripheral to central enhancement, no biopsy Hepatocellular CA: #1 CA in world, due to Hep B, ↑AFP (non-risks: PBC, Wilson’s) Pancreas: Acinar cells: secrete Cl and digestive enzymes, reabsorbs bicarb (in resting state) Ductal cells: cause low bicarb, high Cl Santorini: small duct Wirsung: large duct Lipase/Amylase: only enzyme secreted by pancreas in active form Pancreas divisum: failure of fusion, prone to pancreatitis (Tx: minor duct sphincterotomy)

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Annular pancreas: double bubble (Tx: duodenojejunostomy) 1st test w/ pancreatitis: US (to ck for gallstones) Gallstone pancreatitis Tx: admit, bowel rest, cholecystectomy after pancreatitis resolves Alcoholic pancreatitis w/ CT air: debride ERCP Pancreatitis: 10% occurance Sterile necrotic pancreatitis: no air (Tx: observe) Chronic pancreatitis + dilated pancreatic duct (>8mm): do lat pancreaticojejunostomy Chronic pancreatitis + intractable pain: resect pancreas Gas in pancreas Tx: debride necrosis Ranson’s Criteria: 8 of these means you’re gonna die Admission:

WBC: >16k Age: >55 Glucose: >200 LDH: >350 AST=SGOT: >250

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48 hrs Later: BUN: increases by 5 Ca: <8 Hct: 10% drop Sequestration of fluid: >6L pO2: <60 Base deficit: >4 Pancreatic Lymphoma Tx: CHOP chemo Pancreatic CA: 90% die in one year, biggest risk is smoking, bx required before chemo-rad Pancreatic CA: MC/best survival = head, survival related to clear margins Pancreatic CA invading vascular: biliary bypass + cervical splanchnectomy + G-Jostomy Pancreatic CA markers: CA19-9, mutated K-ras Pancreatic pseudocyst: internal drainage 12wks after acute pancreatitis if growing or sx If pseudocyst connects with pancreatic duct on ERCP: do cystogastrostomy Celiac plexus block: inject EtOH on both sides of aorta for pain relief of unresectable panc mass Insulinoma in pancreatic head Tx: enucleation

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Intraductal Papillary Mucinous Adenoma “IPMN”: ERCP mucous ooze from pancreatitic duct Rectum/Anus: Anal fissure: Botox works on 90% pts Bowen’s disease: intra-epidermal SCC (Tx: WLE)

anal SCC Paget’s disease of anus: itching, apocrine gland CA, +PAS stain (Tx: WLE + LND) Goodsall’s rule for fistula-in-ano: • Anterior fistulas: connect to rectum via a direct

line • Posterior fistulas: travel from posterior to midline

rectum, most common • Tx: Fiber, Sitz baths, NGN cream, Botox,

Laternal internal sphincterotomy Radiation procitis w/ rectal bleeding Tx: formalin Closest rectal CA that can still allow an LAR: 8 cm from anal verge w/ 2cm margins Recurrence at suture line after LAR Tx: APR Anal CA above dentate line: • BCC/SCC Tx: 5-FU/Mitomycin XRT “Nigro

protocol” • AdenoCA/ Melanoma Tx: APR

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Anal CA below dentate line: • BCC/SCC Tx: WLE • Bowens/Pagets Tx: WLE Spleen: Functions of spleen: • filter RBCs • activate killers • storage for 1/3 of platelets • makes RBC Spleen: makes tuftsin, properdin, fibronectin, IgM (blocks encapsulated organisms) Tuftsin: an opsonin made in spleen that causes phagocytosis Hyposplenism: Howell-Jolly bodies (nucleated RBCs) Hereditary spherocytosis Tx: splenectomy + cholecystectomy TTP: enlarged spleen, seizures (Tx: plasmapheresis) ITP: normal size spleen, kid petechia, anti-platelet Ab (Tx: splenectomy, platelets if bleeding) ITP splenectomy: give platelets after ligation of splenic artery Most common location of accessory spleen: splenic hilum

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Splenic vein thrombosis: due to pancreatitis, gastric variceal collaterals (Tx: Splenectomy) Splenic artery aneurysm: resect, bypass if >2cm or pregnant Splenic abscess Tx: CT-guided drainage + abx (splenectomy if multilobular) Splenectomy: for hereditary spherocytosis, ITP, venous thrombus, pyruvate kinase def Splenectomy vaccinations: Strep pneumonia, H. Influenza, N. meningitides “SHiN” Stomach: MALT: H pylori, precursor to gastric lymphoma (Tx: Abx CHOP) GIST “gastric leiomyoma”: c-kit, submucosal, hematemsis (Tx: resection, Gleevac) Gastric Lymphoma Tx: chemo + XRT Gastric AdenoCA risk: >2cm, type A, nitrosamines, pernicious anemia, 6cm margin Gastric cancer palliation: proximal stent, distal

bypass Krukenburg tumor: gastric cancer mets to ovaries

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Virchow’s nodes: gastric cancer mets to supraclavicular nodes H. pylori: H. pylori: live in gastric antrum (Tx: Omeprazole + Amoxicillin + Tetracycline) H. pylori: assoc w/ duodenal ulcers, distal gastric CA, gastric MALToma, GALT lymphoma H pylori gold standard test: histology from biopsy of antrum Clo test: detects urease from H pylori Pathology: Gastritis: • Type A (fundus): autoimmune, pernicious

anemia • Type B (antrum): H. pylori Gastric ulcers: • Type I: type A blood, on lesser curve • Type II: 2 ulcers on lesser curve and duodenum • Type III: pre-pyloric • Type IV: high lesser curve • Type V: NSAID use Gastric varices Tx: splenectomy (b/c of thrombosed splenic vein)

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Operations: Bilroth I: antrectomy + gastroduodenal anastamosis (more marginal ulcers than Roux-en-Y) Bilroth II: antrectomy + gastrojejunal anastamosis (more marginal ulcers than Roux-en-Y) Vagotomy: • Truncal: divides R/L vagal trunk at level of

esophagus • Selective: preserves celiac/hepatic • Highly selective “Proximal”: removes parietal

cells, preserves crow’s foot (normal empty) • Add Pyloroplasty: high solid emptying Post-Vagotomy Symptoms: think of a “rigid” stomach 1) ↓solid emptying (except highly selective

vagotomy) 2) loss of relaxation 3) ↑gastric pressure 4) ↑liquid emptying Truncal vagotomy with pyloroplasty: small meals, high protein • Diarrhea: bile salts colon (Tx: cholestyramine,

octreotide) • Dumping syndrome:

o Early: hyperosmotic fluid shift hypotension

o Late: insulin release hypoglycemia

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Gastric Outlet Obstruction: metabolic alkalosis with ↓Na, ↓K, ↓H due to emesis Afferent Loop Obstrucion: convert to Roux-en-Y Drugs: Aspirin: inhibits gastric mucus and bicarb Metoclopramide: DA blocker, increases LES tone, increases gastric motility Omeprazole: blocks H/K ATPase of parietal cell Zantac: inhibits histamine receptor

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GYNECOLOGY Pregnant lap chole: 2nd trimester PID: 10% infertility per episode 19 y/o PID Tx: IV abx Endometriosis of rectum: blue mass on proctoscopy (Tx: hormones) Irregular menses + rectal bleed: Endometriosis Pregnant appendicitis: 50% premature, 8% babies die, 1% Moms die Pregnant C Diff Tx: oral Metronidazole Gynecomastia: due to estrogen Meig’s syndrome: ovary fibroma ascites, hydrothorax Krukenberg tumor: ovary met from colon/stomach CA, signet cells Ovary CA risk factors: nulliparity, early menarche, late menopause Most common type of ovarian CA: epithelial Ovary CA clear cell type: poor prognosis Ovarian CA Tx: TAH/BSO and omentumectomy Ovary CA w/ mets Tx: TAH/BSO+ omentumectomy, washing Ovary CA staging:

• I: ovary (5yr survival =60%)

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• II: pelvis • III: abdomen • IV: mets

Ovarian Germ Cell Tumors:

• Dysgerminoma: ↑LDH • Choriocarcinoma: ↑β-HCG • Endodermal sinus: ↑AFP

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HEAD AND NECK Erythroplakia: pre-malignant red macule Leuokoplakia: benign white macule that can’t be scraped off (Tx: retinoids) Midline cyst: thyroglossal duct cyst (Tx: “Sistrunk”excision of cyst, tract, center of hyoid bone) Side cyst: branchial cleft cyst (Tx: complete excision including sinus tract)

• Type I: tract from mandible to external auditory canal

• Type II: tract from SCM to tonsillar pillar most common

Parotiditis: due to Staph aureus, dehydrated/old pts (Tx: Methicillin, I&D if not improved) Parotid tumors: small tumors are more likely to be malignant Most common benign parotid tumor: Pleomorphic adenoma (Tx: superficial parotidectomy) Most common bilateral benign parotid tumors: Warthin’s Most common malignant parotid tumor: Mucoepidermoid CA

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Roof of mouth mass: torus (bony growth) Lip cancer: Epidermoid, lower lip more common, (Tx: radical neck dissection if node positive) Tounge cancer: in Plummer-Vinson (dysphagia, anemia) Tx: surgery + XRT Glottic cancer Tx: XRT, but fixed vocal cords require laryngectomy Squamous cell CA: Stage I/II (<4cm, no nodes) – surgery or XRT, Stage III/IV – both Nasopharyngeal SCC: Chinese, EBV, drain to post neck nodes Nasopharyngeal Angiofibroma: teenagers, benign (Tx: embolize internal maxillary artery) Acoustic Neuroma: tinnitus, hearing loss, tumor at cerebello-pontine angle Radical neck dissection: includes CN12, SCM, IJ, submandibular gland Most common submandibular resection nerve injury: marginal mandibular nerve (low lip/chin) Tracheo-innominate fistula: big trach bleed (make trach above 3rd tracheal ring) Frey’s syndrome: gustatory sweating due to auriculotemporal nerve

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HEMATOLOGY O2 dissociation curve: Right shift = CADETS ↑O2 delivery: ↑O2 sat, ↑cardiac output, blood transfusion (Hb) Blood bank: High affinity for O2 due to low 2,3-DPG, high K, low Ca Prevention of febrile transfusion rxn: leukocyte filter Most common blood component to have E coli contamination: platelets (stored at RT) Allergic blood transfusion reaction: due to host Ab Anemia after blood transfusion: give FFP (need factors) MC blood transfusion reaction: fever due to donor RBC (Tx: leukocyte filter) Operating room hypothermia: causes decreased platelet function PRBC: 35-day storage, does not have platelets or factors 5,8 Massive PRBC transfusion: low Ca hypoTN Rates of PRBC infection: • CMV: most common (no routine screening of

WBC)

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• HIV: 1 in 200,000 • Hep: 1 in 30,000 FFP: all clotting factors, 1 unit increases by 3% Cryoprecipitate: has Fibrinogen/Factor 8/VWF give to VWD, Hemophilia A, DIC HIT: happens after 5 days of heparin, white clot DIC: eats all factors, cause is infection Urokinase: converts plasminogen to plasmin Reversal of t-PA/urokinase: Aminocaproic acid “Amicar” -- inhibits fibrinolysis Reversal of elevated PTT pre-op: add cryoppt Thrombin time: monitor thrombolysis Heparin: AT-III cofactor, long PTT, reverse with Protamine sulfate hypotension Warfarin: inhibits Vit-K dep factors (factors 2,7,9,10, Prot C/S) Pre-op warfarin: give heparin until INR < 1.0, stop warfarin 4 days pre-op Warfarin skin necrosis: increased risk with Protein C deficiency, most common on butt Factor 8: NOT made in liver; made by reticuloendothelial system Factor 10: common to both pathways

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Factor 12: Hagemann factor, activated by CABG => need heparin Protein C: degrades Factors 5,8 Protein C deficiency: 5% spontaneous DVT (Tx: warfarin) Factor V Leiden: resistance to activated prot C DVT AT-III deficiency (AD): anticoag if sx Vitamin K: inhibits Factors 2,7,9,10,Prot C/S Plasmin: degrades fibrinogen α2-plasmin inhibitor Platelet dense granules: have Ca, 5-HT, adenosine Von Willebrand’s Disease: long PTT, + ristocetin test, long bleeding time • Type I (AD): low VWF (Tx: DDAVP release

VWF from endothelium), most common • Type II (AD): non-functional VWF (Tx: Cryoppt –

has VWF, Factor 8) • Type III (AR): no VWF (Tx: FFP – has all factors) Glanzmann’s: bad platelet aggregation, low 2b/3a receptor Bernard-Soulier: low platelet adherence to collagen, low 1b

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Hemophilia A (XLR): Factor 8 def, long PTT, newborn has 8 from Mom, don’t aspirate joint Hemophilia B (XLR): Factor 9 def, replace 50% pre-op, C-mas dz Lupus: long Russel viper venom time, long non-correctable PTT Hairy cell leukemia Tx: splenectomy + INF-gamma Lymphoma: LE swelling, thick skin, edema Hodgkins B symptoms: weight loss, fever, night sweats Cooley’s anemia (β-thal): excess RBC production, no HbA (Tx: total body transfusion) Hereditary Spherocytosis Tx: splenectomy + cholecystectomy

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NEUROSURGERY Tyr DA NE Peripheral nerves: regenerate at 1mm/day C5-6: biceps C7: triceps L4: knee jerk L5: foot drop S1: ankle jerk S2-4: anal wink CPP=MAP – ICP (keep >70) Tx: hyperventilation, mannitol, burr hole Cushing's triad: HTN, bradycardia, Kussmaul respirations (slow, irregular) Epidural hematoma: MMA injury, lucid interval, elliptical football “lenticular” shape (Tx: OR) Subdural hematoma: bridging veins, crescent shape, delayed HA (Tx: steroids) Subarachnoid hematoma: berry aneurysm, “worst HA of my life” (Tx: Nimodipine/Phenytoin) 13% of pts with head injury: also have a spinal injury

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C fibers: conduct visceral abdominal pain Peripheral nerve injuries: • Neuropraxia: no axon injury, temp loss of fxn • Axonotmesis: loss of axon continuity,

regenerates at 1mm/day • Neurotmesis: loss of entire nerve, needs surgery Spinal shock: hypoTN, bradycardia, warm ext due to cord injury above T5 Uncal herniation: LOC w/ single pupil dilation Ant spinal artery syndrome: ruptured cerv disk, lose it all (no pain&temp, ↑DTR) Brown Sequard: ½-way cut spinal cord, lose ipsilat motor, contralat pain&temp Central cord syndrome: C-spine flexion, B arm loss of motor/pain&temp (arms lose it all!) Cauda equina: compression of lumbar nerve, leg weakness Anterior Pituitary: adenohypophysis most hormones Posterior Pituitary: neurohypophysis ADH, oxytocin

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Pituitary mass effect: bilateral hemanopsia Pituitary tumor: high ACTH hairy, amenorrhea, depressed Pituitary adenoma: • Prolactinoma: galactorrhea, irregular menses • Chromophobe: non-functional, low hormones Sheehan syndrome: amenorrhea, post-partum lack of lactation Merkel cell CA: red-purple indurated plaques, neuroendocrine tumor, neuron-specific enolase Tuberous sclerosis: tumors of brain/kidney, mental retardation Von Hippel-Lindau: tumors of eye/blood vessels/kidney

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ONCOLOGY Why are cancer pts cachexic? Hypermetabolism, TNF-α VEGF: neovascularization of tumor metastasis No lymphatics: brain, cornea, muscles Most common Mets: • Lung: to brain • Sarcoma: to lung • Papillary thyroid: to lung • Breast: to bone (then lung or brain) • Colon: NOT TO BONE • Thyroid: NOT TO BONE • Liver: to lungs • Prostate: to lymphatics • Testes: to retroperitoneum • Anus: to liver • TO small bowel: melanoma (spreads

hematogenously) Lymph Nodes: Palpable nodes: do LND No palpable nodes: do SLN biopsy Melanoma axillary node Tx: complete axillary node dissection Melanoma LND: Levels I,II,III for tx

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Breast CA LND: Level I only staging Palpable neck LN: do modified radical neck dissection Lung CA paratracheal node Tx: chemo-XRT Tumor Markers: • Breast = Her-2/neu, MUC-1, BRCA • Prostate = PSA • Renal Cell = G250 • Melanoma = gp100 • Thyroid = Ret • Pancreas = K-ras (proto-oncogene that codes

for G-protein) • Colon = CEA, APC (early), p53 (late), DCC • Hepatocellular = AFP • GIST = c-kit Oncogenes/Tumor Suppressors: • c-myc: oncogene for small cell lung CA,

neuroblastoma, Burkett’s lymphoma • sis: oncogene homologous to PDGF • src: proto-oncogene that codes for Tyr kinase • p53: tumor suppressor in cell cycle

regulation/apoptosis • APC: tumor suppressor in cell

adhesion/cytoskeletal fxn

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Tumor suppressor genes: p53, BRCA, Rb, APC Li Fraumeni: p53 mutation => child sarcomas, brain tumors, breast CA, adrenal CA, leukemia Prophylatic operations: • FAP: colon removal • BRCA w/ strong fam hx: breast removal • RET w/ MEN fam hx: thyroid removal Bleomycin/Busulfan: pulmonary fibrosis Vincristine/Cisplatin: neurotoxicity Doxorubicin/Adriamycin: cardiotoxicity Cisplatin: ototoxicity Cyclophosphamide: hemorrhagic cystitis Cyclosporine: inhibits T cell activation Leucovorin: decreases folate, reverse methotrexate effects, increases 5-FU toxicity Levamisole: immunostimulant, anti-helminthic Methotrexate: DHF inhibition Taxol: stabilizes microtubules that build up and cause cell lysis

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5-FU: inhibits thymidalate synthesis PET scan: detects fluorodeoxyglucose involved in high glucose metabolism PET scan: detects CA and infxn, not good for diabetics (normal: brain, thyroid, heart) Radiation: acts on M phase, needs high O2, less skin damage if higher energy Radiation: causes obliterative endarteritis, poor healing due to damaged fibroblasts Contraindications to radiation: multicentric, pregnancy, lupus, scleroderma

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ORTHOPEDICS Sling: clavicle Swelling/pain after sling: compartment syndrome (Tx: fasciotomy) Cast: scaphoid, patella, ankle, calcaneus Closed reduction: dislocations, humerus, talus Open reduction: most (kids get closed reduction) Good clinical healing w/ no improvement on x-ray: gentle active motion w/ protective splint Digit re-implantation: PIP lacerations cannot be re-implanted Lithotomy: peroneal nerve compression foot drop (Tx: fasciotomy) Anatomic snuff box tenderness: scaphoid fracture (Tx: thumb spica cast up to elbow) Navicular fracture: tender snuffbox, cast to elbow Shoulder dislocation: axillary nerve injury Posterior hip dislocation: sciatic nerve injury Post knee dislocation: do arteriogram to rule out popliteal injury Lateral blow to knee: ACL/MCL/MM injury

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Salter Harris fracture type 3-5: crosses epiphyseal plate, open repair Volkmann's contracture: supracondylar humerus fx, hurts interosseus artery (Tx: fasciotomy) Monteggia fracture: ulnar fx with radial head dislocation Fat emboli: petechia, hypoxia, urine Sudan stain, CXR patchy infiltrate (Tx: ↑PEEP, ↓TV) Bone tumors: • Ewings sarcoma: onion layering, pseudorosettes

(Tx: XRT) • Osteosarcoma: sunburst x-ray • Giant cell tumor: soap bubble x-ray

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PEDIATRICS Strawberry hemangioma: leave alone unless persists until 8y/o steroids Cystic hygroma: neck lymphangioma, gets infected (Tx: resection) TE Fistula: Tx=right extrapleural thoracotomy • Type A: esophageal atresia alone, gasless abd

x-ray • Type C: esophageal atresia + TE fistula

“common” most common o Tx: R thoracotomy w/ end-end

anastamosis o Complication: new GERD

• Type E: "H" configuration of trachea/esophagus Pulmonary sequestration: newborn resp infections (Tx: resection) • Intralobar: pulmonary venous drainage • Extralobar: systemic venous drainage (lung not

connected to bronchus) Congenital Lobar Emphysema: cartilage not develop, hyperinflation of one lobe Congenital Diaphragmatic Hernia: on left, both lungs are bad, 50% survival Gastroschisis: intrauterine rupture of umbilical cord

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Oomphalocele: midline defect with peritoneal sac, may have other organs Meconium ileus: do gastrograffin enema, CF pts, obst in terminal ileum, no air-fluid level (thick) Hirschprung's: main cause of colon obstruction, do rectal biopsy Imperforate anus: may have urine meconium if fisutula need colostomy Necrotizing enterocolitis: bloody stool with first feeds Tx: OG tube, abx, TF Biliary atresia Tx: Kasai procedure by 3m/o (hepatoportoenterostomy) Duodenal atresia: double-bubble sign (Tx: duododuodenostomy) Intestinal atresia: due to intrauterine vascular event (Tx: resection) Pyloric stenosis: vomiting that hits the wall, RUQ olive mass (US pyloromyotomy) Malrotation: bilious vomiting < 2y/o Ladd's procedure for malrotation: appy, take down bands, fix cecum in LLQ Meckel's diverticulum: on anti-mestenteric border of SB, persistent vitelline duct, Littre hernia Intussusception Enemas: max air pressure=120mmHg, max barium height=1meter

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Resistant intussusception Tx: enema resection + appendectomy Umbilical hernia: repair at 5y/o Inguinal hernia: on right, repair immediately due risk of incarceration Undescended testicle: repair at 2 y/o after MRI, increased risk of testicular CA Testicular torsion: high riding testicle (Tx: B exploration via scrotal incision to pexy testicles) Felty’s: Juvenile RA, splenomegaly, neutropenia Neuroblastoma: <2y/o HTN, on adrenals, high VMA, N-myc, from neural crest cells Wilm's tumor: prognosis based on tumor grade, mets to bone/lung (Tx: nephrectomy) Leukemia: most common child malignancy 1st sign of child CHF: hepatomegaly

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PHARMACOLOGY Steady state: 5 half-lives VD: total drug/plasma conc (large VD most of drug is sequestered) 1st order elimination: constant drug percentage metabolism over time • Ex: 10% of drug eliminated every 2 hours

(conc=100mg/dL) o T:0hrs [D]=100mg/dL o T:2hrs [D]=90mg/dL o T:4hrs [D]=81mg/dL

Peak: 4 hrs after dose (if too high decrease dose) Trough: 2 hrs before dose (if too high give less often) Clinical Trials: • I: Safe? • II: Effective? • III: Better? • IV: Marketing α1: vasoconstricts α2: ↓sympathetics β1: revs heart up β2: bronchodilates

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↓Warfarin Levels (p450 activation): Barbs, Rifampin, Phenytoin ↑Warfarin Levels (p450 deactivation): Cimetidine, INH, MAOI, Amiodarone, Flagyl, EtOH Nipride (CN) toxicity Tx: amyl nitrate, then Na nitrate MetHb Tx: methylene blue Carbon monoxide: falsely ↑O2 sat. Give 100% O2 to reduce half-life of CO from 5h 1h Aminoglycosides: bactericidal, prevent RNA protein synthesis of cell wall receptors Amphotericin B: binds sterols and alters fungal cell wall, 80% RF Ampicillin: made to tx enterococcusive transport Bactrim: erythema multiforme Ceftriaxone: causes GB sludge and jaundice Ciprofloxacin: DNA gyrase inhibition Clindamycin: prolong neuromuscular blockade Erythromycin: binds motilin receptor Fluoroquinolones: inhibits DNA gyrase, bacteriocidal

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Gentamicin: peak=5-10, trough<1, bacteriocidal Metronidazole: produces oxygen radicals, causes peripheral neuropathy Penicillin: works against gram positive cocci/rods Sulbactam/Clavulanate: inhibit β-lactamase Tetracyline, -mycins: bacteriostatic, rev binding to ribosome Vancomycin: binds plasma membrane and alters cell wall (peak:20-40, trough:5-10) Aminoglycoside resistance: decreased active transport due to modifying enzymes MRSA: due to change in bacteria binding protein Penicillin resistance: plasmids coding for β-lactamase (enzymatic degradation) Vancomycin resistance: due to cell wall binding proteins Aspirin: irreversibly binds COX, effective for 7 days (life of platelet) Demerol: don’t use with MAOIs Glucocorticoids: cause insulin resistance Indomethicin: blocks prostoglandin production, low renal blood flow Nitroglycerin: relaxes veins

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Nitroprusside: dilates arteries and veins cyanide toxicity Toradol: causes bleeding, renal failure, ulcers TB Tx: • Rifampin – orange secretions • Isoniazid + Vit B6 – seizures • Pyrazinamide – liver toxicity • Ethambutol – eye problems: impaired color

vision, retrobulbar neuritis

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SKIN/SOFT TISSUE Blood flow to skin: autonomic Tissue hypoxia: causes increased angiogenesis Stages of healing: • Inflammatory: Hemostasis and inflammation • Proliferative: Epithelial migration and

proliferation • Maturational: Contraction, scarring and

remodeling of scar Nicotine decreases wound healing: ↓blood flow (vasoconstrict), ↓fibroblasts, ↑thrombosis HIV: normal wound healing Wound healing arrivals: Platelets PMNs (day 2)

MP/T (day 3/4) Fibroblasts (day 5) Most important cell in wound healing: MP Epithelial cells: come from hair follicles Opening >5 day old wound: quicker healing the 2nd time (cells in place) 1˚ Intention wound healing most important factor: tensile strength of wound Max tensile strength of wound: at 8 weeks, occurs by collagen crosslinking 2˚ Intention wound healing: via contraction Most important factor for contraction: epithelial integrity (avoid leakage)

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What causes wound contracture? Myofibroblasts smaller wound (more abundant in butt)

Vit A: decreases the effect of steroids on wound healing via TGF-β Vit C wound healing: via Pro hydroxylation Collagen: Glycine q3 α-ketoglutarate; needs Vit C, O2, Fe for crosslinking by Prolyl OHase

• Type I: Scars, most abundant • Type II: Cartilage • Type III: Healing wounds, low in Ehlor-Danlos,

changes to type I (at week 3) • Type IV: BM Collagen production: days 3-21, then more crosslinking to increase strength Keloids: not confined to original scar area (Tx: XRT, steroids, silicone injections) Keloid: extends beyond wound margins, no collagen breakdown Scars: crosslinked collagen Hypertrophic scar: not extend beyond wound margins Reason fetus has no scars: hyaluranic acid FTSG: contracts less, good for palms, less likely to survive

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STSG: donor site regenerates from hair follicles and skin edges Skin graft survival: imhibition (osmotic exchange of nutrients); neovascularization (day 2-7) MCC skin graft loss: seroma lifts graft to prevent neovascularization Flap necrosis: due to venous thrombosis Gas gangrene Tx: PCN + debridement Necrotizing fasciitis: air in fascia (Tx: I&D and PCN) Fournier’s gangrene Tx: I&D, Amp+Gent+Clinda Brown recluse spider bite Tx: Dapsone Hidradenitis: infections of axilla and groin, in apocrine sweat glands Immediate post-op fever + purple skin edges: Clostridium perfringens (Tx: OR + PCN) Abscess requiring open drainage: pancreas, perirectal, tenosynovitis Enlarging anterior thigh mass: do core needle bx Risks for melanoma: moles BCC: most common skin CA, palisading nuclei, above mouth, need 0.5cm margins SCC: usually below mouth

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Marjolin’s ulcer: squamous cell carcinoma in chronic wound Melanoma: focal mets to subcutaneous tissue (nodular=worst type) Melanoma sites: (male back or female leg) > eyes > rectum Mohs micrographic excision: >2cm, aggressive, recurrent, weird margins, perineural invasion Sarcoma: staging based on grade (not size), spread hematogenously (not lymphatics) Extremity Sarcoma bx: • <4cm: excisional • >4cm: incisional bx w/ longitudinal incision (less

lymphatic disruption, excise later) • >5cm or close margins or high grade: post-op

radiation Margins of excision for melanoma: • In situ: 0.5cm • <1mm: 1cm • 1-4mm: 2cm • >4mm: 3cm • >1.5cm: do SLN biopsy • Facial: 1cm • Subungual: amputation

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THORACIC Cardiac: ASA Class Simplified: • I: healthy • III: stable angina, previous MI, moderate COPD • VI: organ donor Cardiac Physics: Wedge pressure: like a gas tank, ~LVEDP, increased by MR, Left heart failure What determines cardiac O2 consumption and energy use? Ventricular wall tension Indirect calorimetry: O2 consumed/ CO2 production Lowest O2 tension: coronary sinus Highest O2 tension: renal vein Swan Catheters: • RA: 1-6 mmHg • RV: 15-30 mmHg • PA: 6-12 mmHg • PCWP: 6-12 mmHg Wedge pressure distances: • R subclavian: 45cm • R IJ: 50cm • L subclavian: 55cm • L IJ: 60cm

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Intra-aortic balloon pump (IABP): inflated during diastole to coronary perfusion and ↓afterload IABP tip: 2cm below top of aortic notch in desc aorta, deflates on p wave, inflates on T wave EKG of high K: peaked T waves Cardiac Pathology: Atherosclerosis: MP (foam cell) migration SM prolif intimal disruption thrombus Atrial Myxoma: has spindle-shaped cells in other thrombi Mitral Stenosis: can be caused by rheumatic fever, may regurg if valve is bad PDA: Tx w/ Indomethicin close surgically at 6mo VSD: most common congenital heart defect, 50% close by itself IHSS: DA increases ventricular outflow obstruction Causes of infant cyanosis: Tet of Fallot, Truncus Arteriosus, TAPVR, Transposition of GA Non-cyanotic heart problems: PDA, VSD, ASD “the D’s” Cardiac tamponade: hypotension due to low diastolic filling 1st sign of cardiac tamponade on TEE: distal RA collapse

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Acute MI: ↑PAWP due to ↑EDV Peri-operative MI: S3 gallop Post-MI (Day 2-7) Complications: VSD, papillary muscle rupture, LV free wall rupture (Dx: TEE) CABG: for triple vessel dz, >50% left main, or 70% LAD + 2nd vessel s/p CABG: check Mg2+ s/p CABG highest mortality risk: pre-op cardiogenic shock Patency Rates: • IMA LAD: 90% at 20yr • Saphenous vein grafts: 80% at 5yr Most common site of aortic dissection: ascending aorta Thoracic Aortic Dissection: tearing pain, unequal pulses, CXR widened mediastinum • Type A: ascending aorta (Marfan's, syphilis)

emergency surgery (>8cm) • Type B: descending aorta (atherosclerosis,

trauma) tx HTN (Nitroprusside + Esmolol) Abdominal Aortic Aneurysm: ripping pain, pulsating abd mass, ↑matrix metalloproteinases • >7cm: emergent repair of aorta (no CPR) • Needs revascularization, no backbleeding from

IMA AAA repair with BRBPR: ischemic colon due to loss of IMA, necrosis on sigmoidoscopy

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Tissue valves: short lasting, good for Tricuspid and pregnant women, no coumadin Artificial valves: long lasting, need coumadin Cardiac Drugs: Digoxin: inhibits Na/K ATPase to ↑Ca, slow AV conduction, ischemic gut, low splanchnic flow Dobutamine: no effect on BP, vasodilator via β1

Dopamine mechanism of action: • High dose: α1 vasoconstricts • Med dose: β1 contracts heart • Low dose: D2 perfuses kidneys L-Arg NO: relaxes SM via cGMP, vasodilation, released from vasc endothelium NO synthase: stops platelet aggregation, vasodilation Propranolol: decreased ventricular response to A Flutter V Tach Tx: Lidocaine

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Pulmonary: Aging: ↓FEV1 and FVC, ↑FRC and A-a gradient Obesity: blunted response to CO2 Anatomy: “VET from 8-10-12” • T8: Vena cava • T10: Esophagus • T12: Thoracic duct/aorta Type I alveoli: gas exchange Type II alveoli: make surfactant Pleural space: makes 600-1000mL per day RLL: most accessible to bronchoscopy Pulm sequestration: aberrant artery from aorta Apical lung: high V/Q (ratio changes when supine for long periods) Pulm vascular resistance: measure w/ PA cath PA cath: in zone III of lung, balloon inflated while advancing, ↑PEEP will ↑wedge pressure Net fluid movement to lung interstitium: normal due to Starling’s law Lung compliance (want it high): ∆vol for given ∆pressure ↓ Lung compliance: ARDS, pulm edema

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PEEP: ↑FRC and compliance, keeps alveoli open, ↑ADH, ↓CO, ↓urine output FRC: air left in lungs after expiration IC: air breathed in from FRC FEV: greatest vol that can be exhaled VC: max air you can exhale, VC=IC+ERV RV: air left after max exhalation FRC: air left after normal exhalation TV: air exhaled w/ normal inspiration/expiration The Ventilator: • Oxygenation: FiO2, PEEP • Ventilation: RR, TV Best ventilation test: pCO2 Dead space: ventilation, no perfusion (e.g. ventilator tubing, anatomic) Shunt: perfusion without ventilation due to alveolar collapse Single lung ventilation: causes shunting b/c of increased resistance Most sensitive extubation criteria: rapid shallow breathing index

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Prolonged ventilation: overfeeding (↑CO2), ↓Phos (need to have ADP ATP) What causes post-op hypoxia? V/Q mismatch due to alveolar hypoventilation ABG: metabolic if both are increased

• pH=7.4 • pCO2=40 NG tube: metabolic alkalosis Renal failure: metabolic acidosis High end-tidal CO2: lung collapse or atelectasis Low end-tidal CO2: CO2 embolus (unstable VS) or disconnection from ventilator (stable VS) How to distinguish between ARDS and pneumonia: BAL has bacteria in pneumonia ARDS: CXR B infiltrates, wedge pressure <18, pO2:FiO2 < 200 ARDS Tx: ↓TV, pressure-control ventilation, ↑PEEP Air embolus Tx: left-side-down Trendelenburg RA central line air aspiration Spontaneous PTX: males, 50% recur, right apex, thorascopy for cont air leak, ↑insp pressure

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Recurrent spontaneous PTX Tx: VATS + pleurodesis for >2cm bullae Tension PTX: male with emphysema, hypoxia, ↑airway pressure on induction (Tx: chest tube) What kills you during a Tension PTX? SVC compression Loculated empyema Tx: VATS MC right lung injuries: spontaneous PTX, tracheo-bronchial injury, Ivor-Lewis chylothorax MC left lung injuries: blunt diaphragm injuries, Boerhaave’s, aortic arch chylothorax Chylothorax: due to lymphoma (Tx: radiation) Unilateral Chylothorax: thoracic duct is on right until T4-T5, then it is on the left • Right chylothorax: due to Ivor-Lewis • Left chylothorax: due to distal aortic arch

procedures Pancoast Tumor: L lung drains into R mediastinum 1) Horner’s syndrome: due to invasion of sympathetic chain, arm pain 2) Thoracic outlet syndrome: C8-T1 ulnar paresthesias due to cervical rib, weak hands/triceps

Thoracic outlet syndrome Tx: resect 1st rib (60% cure)

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SVC syndrome: lung CA invades SVC to cause face/arm swelling (Tx: radiation) Mediastinal lymph node: non-caseating granuloma CXR popcorn lesion: hamartoma Non-small cell lung CA: asymptomatic nodule on CXR Most common lung CA: adenocarcinoma (1st sign: cough) Paraneoplastic syndrome: • Small cell: ACTH, ADH • Squamous cell: PTH-related peptide Lung CA Staging (TNM): • T2: >3cm • T3: invasion <2cm from carina • T4: unresectable

o N1: hilar o N2: mediastinal o N3: unresectable

Pre-op bads: pCO2>50 or pO2<50.

• Pre-pneumonectomy FEV1: >2L • Pre-lobectomy FEV1: >1L • Pre-wedge rxn FEV1: >0.6L • Need predicted post-op FEV1>0.8L

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THYROID/PARATHYROID T3: active (3x as T4), half-life=3 days PTU: block conversion to T3 Cold nodule: implies cancer Thyroid nodule w/u: H&P FNA if normal TSH (iodine scan if low TSH) Post-URI thyroiditis: ear pain, neck swelling, hard to swallow (Tx: ASA) Thyroid storm tx: Propanolol Parafollicular C cells: make calcitonin (↓Na), from neural crest cells Calcitonin: inhibits osteoclasts, decreases serum Ca, opposite of PTH Superior parathyroid: from 4th pharyngeal pouch in ant. mediastinum Inferior parathyroid: from 3rd pharyngeal pouch DiGeorge (low Ca) if both absent Most common location of missed parathyroid: anatomic location Most common location of ectopic parathyroid: thymus PTH: phosphate trashing hormone, inhibits peroxidases

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PTH: ↑Ca resorption by kidney, ↑osteoclastic Ca release from bone HyperPTH: PRAD-1 oncogene, radiation exposure, ↑Ca, osteitis fibrosa cystica • 1˚ HyperPTH: adenoma (↑PTH, ↑Ca, ↑renal

cAMP, Cl/PO4 >33) • 2˚ HyperPTH: renal failure • 3˚ HyperPTH: kidney transplant Pregnant HyperPTH Tx: PTU, then thyroidectomy FHH: low urine Ca MCC hypoPTH: thyroid surgery MEN I: PARATHYROID (↑Ca, ↓QT), Pituitary (PRLoma), Pancreas (VIP/insulin/gastrinoma) • Tx: parathyroidectomy first MEN IIa: PARATHYROID, PHEO/THYROID (↑calcitonin) • Tx: prophylactic thyroidectomy MEN IIb: oral/GI neuromas, PHEO/THYROID (↑calcitonin, Marfan's habitus) Graves: TSHr Ab, exopthalmos, pretibial myxedema Wolff-Chaikoff: KI (“Lugol's sol’n”) inhibits TSH to treat thyroid storm low T3/T4 Thyroid Cancer:

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• Papillary: lymphatic spread, local invasion tells survival (not nodes), psammoma bodies, Orphan Annie nuclei, kids node +, multicentric, lateral aberrant thyroid test, young females, exposure to radiation (Tx: thyroidectomy + MRND if LN spread)

• Follicular: hematogenous spread to bone, older females

o Tx: thyroidectomy 131I thyroid replacement to suppress residual CA, follow TG)

o Hurthle cell subtype: older pts, benign (Tx: total thyroidectomy)

• Medullary: amyloid, bilat, Ret, from C cells, gastrin test (Tx: neck dissect if node +)

• Anaplastic: rapidly lethal (0% survival in 5 years)

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TRANSPLANT/IMMUNOLOGY Most important transplant criteria: negative cross-match Positive cross-match: recipient has preformed Ab

can’t do transplant Cross-match test: mix donor lymphocytes (Ag) with recipient serum (Ab) Graft vs Host Disease: T cells Chimera: lymphocytes from donor and recipient after transplant Transplant Rejection: • Hyperacute: Pre-formed Ab activates

complement thrombosis (Tx: remove organ) o Usually due to ABO incompatibility, type

II hypersensitivity rxn • Acute: T cells, due to foreign MHC Ag (Tx:

OKT3 to block T cells) • Chronic: Fibroblasts (Tx: remove organ) MCC of death in donor: PE MCC of death in recipient: MI Heart transplant chronic rejection: graft thrombosis

silent MI Lung transplant chronic rejection: bronchiolitis obliterans

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Liver transplant chronic rejection: bile duct obstruction (↑Alk Phos) 1 year Survival Rates: • Heart transplant: 80% • Liver transplant: 70% Post-transplant Complications: • Oliguria: ATN • Biliary stricture: ischemia • Infection: CMV (inclusion bodies) Tx:

Ganciclovir • Malignancy: skin CA • Lymphoproliferative disorder: due to EBV (Tx:

↓immunosuppression or chemo-XRT) Kidney transplant rejection: use left kidney (longer renal artery) 1) Proteinuria: sign of renal vein thrombosis 2) ↑Cr: do US a) Normal: do bx if acute tubulitis or vasculitis (Tx: pulse steroids for rejection) b) Fluid w/ ↑Cr: urine leak (Tx: perc drain + ureteral stent) c) Narrow anastamosis: do angiography w/ stent placement

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Azathioprine: purine analog, inhibits T cells Cyclosporine: blocks IL-2/T cell mRNA encoding, nephrotoxic, binds cyclophilin receptor FK506: “tacrolimus”, blocks IL-2 production, potent Mycophenylate: blocks purine synthesis, ↓T/B proliferation OKT3: T cell-CD3 monoclonal Ab causes opsonization of T cell (tx for steroid-resistant rejection) Prednisone: blocks IL-1 Zenepax: IL-2 Ab, use immediately after transplant B cell function test: Measure serum Ig T cell function test: Lymphocyte proliferation assay (give Ag, see if lymphocytes come) Test for cell-mediated immunity: intradermal skin test IL-1 (from MP): causes fever IL-2 (from T cells): TK and NK cells to kill tumors IL-4: B cells to make Ab IL-7 (from thymus/bone marrow): make B/T precursors MHC-1: CD8 activation, on all nucleated cells

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MHC-II: CD4 activation, on B/monocytes/dendrites; 2 chains. NK: kills cells that don’t have self-MHC; protects against cancer IgA: found in secretions, breast milk, Peyer’s patches IgE: histamine release from basophils/mast cells IgG: made 2nd crosses placenta IgM: made 1st; splenectomy decreases levels TNF-α: (MP) stimulated by endotoxin to cause apoptosis “death ligand” and cachexia in CA pts TGF-β: stimulates fibroblasts fibrosis, inhibits cell proliferation, angiogenic INF-α: stops viral replication PDGF (Regranex): attracts fibroblasts matrix deposition, collagen formation GmCSF: increases PMN/MP in chemo pts Prostacyclin (from endothelium): inhibits platelets, vasodilates, bronchodilates Thromboxane: “thrombosis” of platelets by Ca, vasoconstriction of arteries AND veins Acute phase response: uses albumin to make CRP, amyloid, haptoglobin

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CXC “cystine” chemokines: starts wound healing and angiogenesis Antibody: variable region recognizes Ag Basophils: release histamine in blood Mast cells: release histamine in tissues Langerhans cells: Ag recognition, contact hypersensitivity Dendritic cell: Ag-presenting cell “APC” Selectins: select mature WBCs Integrins: integrate WBC to endothelium via ICAM-1 Cadherins: tight cell-cell contact Complement: C3a/C5a = anaphylatoxins, paths converge at C3 • Classic pathway: Ab • Alternative pathway: Bacteria SIRS: need at least 2 of these

• Temp >38 • HR >90 • RR>20 • WBC>12k • Bands>10% • CO2<32

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Early wound infection: bowel leak or C. perfringens Wound Infection Risk: long op, hematoma, old, chronic dz, malnutrition, immunosuppression Most common non-surgical cause of infection: UTI due to Foley Most common cause of bloodstream infection: central line sepsis POD#1 atelectasis fever: caused by alveolar MP

IL-1 Systemic candidiasis: decreased T cell function Clostridium perfringens: GPR (no WBC) Staph aureus: slimey, coagulase + Endotoxin: Lipid A from LPS of GN bacteria TNF-α release Most potent Exotoxin: Strep Angiodema Tx: Benadryl (tx resp distress) + Epi (tx throat swelling) Hereditary Angioma Tx: epsilon-aminocaproic acid Myasthenia Gravis: ACh receptor Ab (Tx for failed medical therapy: thymectomy) Gout Tx: Indomethicin or Colchicine

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TRAUMA Dirty wound tetanus prophylaxis: toxoid + Ig Puncture wound at tip of finger: lateral finger incision Stable mediastinal widening: get dynamic CT chest Indications for thoracotomy: penetrating trauma with loss of VS in ER Exploration of bleeding: >250cc/hr over 3 hrs, or >1500cc initial, or 2.5L/24hr + DPL: 10cc frank blood, >100,000rbc/mm, >500wbc/mm, food, bile, bacteria ex lap DPL: misses retroperitoneal bleeds Source of traumatic hypotension: always abdomen until proven otherwise FAST: misses SB tear and free fluid <80cc, checks for blood in 4 spaces:

• Pericardium • Perihepatic fossa • Perisplenic fossa • Pelvis Neck zones: I: below cricoid II: cricoid to angle of jaw OR III: jaw to skull

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GCS: • Motor: 6=commands, 4=withdraws to pain • Verbal: 5=oriented, 3=inappropriate • Eye opening: 4=spontaneous, 2=to pain GCS<10: intubate GCS<8: needs ICP monitor GCS<5: 50% mortality Head injury w/ lots of pee: DI Blunt diaphragm injury: on left, NG in chest (Tx: laparotomy) Tracheo-bronchial injuries: on right, breathing worse after chest tube placement GSW to abdomen + hypoTN: go straight to OR Ligation of right renal vein: OK due to collaterals Traumatic pancreas transaction Tx:

• If lateral to SMA: distal pancreatectomy • If medial to SMA: Whipple

Abdominal compartment syndrome: hypoTN, low urine output, bladder pressure >25mmHg Bloody urethra: retrograde urethrogram suprapubic catheter, repair when inflammation gone Unstable displaced pelvic fractures: pelvic external fixator angiography

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Lumbar transverse “chance” fracture: leads to small bowel injury Femur fracture: reduce in trauma bay before transportation Post-trauma insulin resistance: due to cortisol

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UROLOGY Pre-renal azotemia: low volume, FeNa <1%, BUN:Cr >20, UNa<20, urine osmolality>500 Renal failure: glomerulus damage, BUN:Cr <20 Post-renal azotemia: obstruction, UNA > 40 Most sensitive test for pre-renal vs RF: FeNa FeNa: urine/plasma Na divided by urine/plasma Cr Most common cause of acute renal failure: intra-op hypoTN Contrast-induced renal failure: avoid by Na acetyl cysteine prior to contrast Renin: released by the kidney (J-G), increased by ↓CO • Liver: Renin converts ATogen to AT-I • Lung: ACE converts AT-I to AT-II =>

vasoconstricts, increases Aldo Adrenal medulla PNMT: converts NE to Epi Aldo: works on DCT, reabsorbs Na, excretes H/K PT: calcidiol to calcitriol Macula Densa: senses Iow Na renin Urge UI: gotta go right now (Tx: urinate frequently

Oxybutinin/Imipramine)

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Stress UI: pee with sneeze, low Valsalva leak point (Tx: Kegel Pessary Pseudoephedrine) Overflow UI: dribble (Tx: TURP/ self cath, Bethanochol for MS pts) Kidney stones Tx: • .4-4cm: Lithotripsy • >4cm: Operate • Septic: Stent to drain pus Epo: low production in ESRD, stimulated by hypoxia (high Epo: kidney CA) ↑Epo: renal cell cancer ↓Epo: end-stage renal disease Renal cell cancer: mass, abd pain, hematuria, ↑Epo, grows into IVC • Stouffer syndrome: ↓hepatic fxn Bladder Injury: • Extraperitoneal: Foley x 2wk • Intraperitoneal: Repair Bladder injury w/ pelvic fx Tx: Foley only (extraperitoneal) Bladder injury w/o pelvic fx Tx: OR with 2 layer closure and Foley (dome rupture)

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Ureteral injury: absorbable suture, stent, drain (no ureteral dissection due to blood supply) • Above pelvic brim: If 1cm missing re-

anastamosis, if 2cm missing perc drain • Below pelvic brim: re-implantation Urethra injury: bloody meatus, trauma, high prostate retro urethrogram suprapubic cath Grade 3/4 renal injury: surgical repair Normal sperm: 20million sperm/cc with 4-5cc, <50% abnormal, 50% motile after 5 days, high pH Epididymus: drains into vas deferens Seminiferous vesicles: connected to vas deferens Cryptorchidism: <2 y/o orchiopexy to increase fertility, still has 3-13x risk of testicular CA Testicular torsion Tx: bilateral orchiopexy Varicocele: dilatation of panpiniform plexus “bag of worms” Phimosis needing Foley: make dorsal slit Testicular mass bx: orchiectomy via inguinal incision, then bx it (not trans-scrotal) Seminoma: malignant (Tx: XRT, platinum chemo if node +)

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Non-seminomatous testicular CA: AFP, β-HCG (Tx: orchiectomy + retroperitoneal LND) Prostate mets to bone: osteoblastic, radiodense Ejaculatory dysfunction after prostatectomy: due to retrograde ejaculation Leuprolide: medical orchiectomy Metapyrone/Aminoglutethimide: medical adrenalectomy Pre-op UTI: increases risk of wound infection Uremia: causes bleeding due to defective platelet function (↓GP/VWF) Tx: dialysis Proteus infection: struvite “staghorn” stones Pyelonephritis: due to E coli, Klebsiella, Proteus, Pseudomonas Waterhouse-Friedrickson: meningococcal sepsis causes adrenal hemorrhage Pneumaturia causes: diverticulitis (colovesical fistula), sigmoid cancer, Chron’s Renal osteodystrophy: dialysis causes Al buildup in bones. Kidney loses Ca, keeps PO4, low Vit D => 2˚ hyperPTH (Tx: parathyroidectomy) Asymptomatic adrenal mass: operate if >4cm or changing Oncocytoma: distal tubule benign tumor

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Bladder extrophy: adenocarcinoma (precursor = cystitis glandularis) Sigmoid CA invading bladder dome Tx: en bloc partial cystectomy Bladder SCC: Schistosoma haematobium, bladder calcification (Tx: Praziquantel) Bladder transitional cell CA: smoking, cyclophosphamide (Tx: BCG)

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VASCULAR Central Lines: R IJ (kinks, thrombosis), L Subclavian (stenosis), Femoral (infxn) Purulent thrombophlebitis Tx: resect vein Claudication initial Tx: exercise, smoking cessation, diet Ankle Brachial Index (ABI): • Normal: 1 • Claudication: 0.5 – 0.8 (decreases with exercise • Pain at rest: < 0.4 Compartment syndrome: damage deep peroneal nerve can’t dorsiflex foot Compartment syndrome: pressure > 30, leave open 5-10 days, ↑K, pain on passive motion CEA Indications: >70% stenosis or >60% stenosis with sx Young person with symptomatic carotid stenosis: fibromuscular dysplasia (Tx: angioplasty) CEA 5-yr stroke rate: • No sx: 11% 5% • Sx: 26% 9%

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SAPPHIRE trial: coronary artery stents are not inferior to CEA in high risk patients CEA CN injury: vagus nerve hoarseness CEA post-op stroke Tx: thrombectomy Recurrent carotid stenosis: myointimal hyperplasia Internal carotid artery obstruction: retrograde flow to ophthalmic artery Symptomatic carotid stenosis and AAA: fix carotid first 5-yr AAA rupture risk: increased w/ HTN, COPD

• <5cm: 20% • 5-7cm: 33% • >7cm: 95% MCC AAA: atherosclerosis Infected aortic graft Tx: Axillo-BiFem bypass resect graft, ligate aorta Popliteal aneurysm: 50% bilateral, 33% have AAA, do bypass b/c risk of emboli Complication of popliteal aneurysm: thrombosis Splenic aneurysm: tx if >2cm, has sx, or is of child-bearing age

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SMA thrombus: narrowing at takeoff SMA embolus: meniscus sign (Tx: embolectomy + necrotic bowel rxn + 2nd look) Effort thrombosis: upper extremity venous thrombosis (Tx: thrombolytics + heparin) MCC of acutely ischemic leg: proximal thigh ischemia due to external iliac Early sign of graft thrombosis: Doppler change (biphasic monophasic) Baseball pitchers: subclavian vein thrombosis after throwing (Tx: local t-PA, heparin) Angioplasty: best for common iliac Cold pulseless foot: cardiac embolism (Tx: embolectomy) Reperfusion free oxygen radicals: due to xanthine oxidase Reperfusion injuries: due to neutrophils AVM: sudden LOC, young people bleeds or old people aneurysms (Tx: resection) Mesenteric ischemia: do angiogram

• Constricted vessels from pressors (Tx: Papavarine or NGN injection)

• Thrombus (Tx: TPA) • Embolus (Tx: embolectomy)

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Fibromuscular dysplasia: young woman with HTN (Tx: R renal artery angioplasty) Takayasu arteritis: young female with “temporal arteritis” of aorta/pulm artery (Tx: steroids) Glomus cell tumor: painful digit tumor composed of blood vv and nerves (Tx: shell it out)