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Morning ReportJen Menon, PGY2

9/23/2013

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Youre the intern coming on this morningand you get this patient signed out

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HPI

CC: Syncope HPI: 16 year old previously healthy male presents to ED

after 4-5 syncopal episodes at home. Patients motherstates that he was on the phone with his girlfriendupstairs when she heard a thump. When she foundhim, he was on the ground, talking to his girlfriend, andhad no recollection of the event. Mom left, he finishedthe conversation, then mom heard another thump andfound him on the ground, laughing. Patient again hadno recollection of the event. He then started walkingdown the stairs and mom notes that he lookedunsteady. He again passed out and went limp. Momnoted pallor and sweating, and was deeply concerned,so called 911. Glucose was checked and was 58, so IVglucose was given. He was brought to PCMC. He hasnever had an episode like this before. He is admitted tothe inpatient team.

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More History

PMH: No major illnesses. Immunizations UTD. PSH: No surgeries

Medications: None

Allergies: NKDA

Diet: Normal for age FHx: No history of childhood cardiac illness. No

history of sudden death or SIDS in the family.Mom has hypertension.

SHx: Lives in Utah with parents and 2 siblings.

Has a girlfriend who he has been seeing forabout 2 months. Denies sexual activity, tobaccouse, alcohol use, and illicit drug use.

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Review of Systems

Constitutional: Decreased appetite, diaphoresis. Denies fevers, fatigue, weightloss, chills, and weakness.

HEENT: No changes in vision or hearing, no recent URI symptoms or sore throat.

CARDIOVASCULAR: Denies exercise intolerance, orthopnea, and dyspnea onexertion. No chest pain, palpitations, or edema.

RESPIRATORY: No shortness of breath, cough or sputum.

GASTROINTESTINAL: No abdominal pain, nausea, vomiting or diarrhea.

No hematochezia or melena. GENITOURINARY: Denies dysuria, increased urinary frequency.

NEUROLOGICAL: Per mom, he was behaving funny and not quite actinghimself. He was confused and laughing inappropriately at the situation.No headache, dizziness, syncope, paralysis, ataxia, numbness or tingling in theextremities. No change in bowel or bladder control.

MUSCULOSKELETAL: No muscle, back, or joint pain.

HEMATOLOGIC: Pallor following syncope. Otherwise, no anemia, bleeding orbruising.

SKIN: No rash or itching.

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Physical Exam

T 36.8. HR 94. RR 20. BP 120/54. SaO2 96% on Room Air.WEIGHT - 69.6 Kg, (72%ile) HEIGHT - 170 cm, (28%ile), BMI - 24.1

GENERAL: fit young man, quiet, laying down in bedHEAD: normocephalic, atraumatic.EYES: pupils equal, round, and reactive to light, extraocular movements intact,conjugate gaze, no conjunctival injection, sclera anicteric.NOSE: no discharge or obstruction.OROPHARYNX: moist mucus membranes, tonsils 2+ without exudate, no pharyngeal

erythema or lesions.NECK: supple without lymphadenopathy or tenderness to palpation.CARDIOVASCULAR: normal rate, rhythm, and S1/S2 without murmur or gallop.Pulses appropriate. Capillary refill time 2 seconds.LUNGS: clear to auscultation bilaterally, good air flow, no retractions.ABDOMEN: soft, non-tender, non-distended with active bowel sounds and no massesor hepatosplenomegaly.EXTREMITIES: all extremities warm and well perfused. No cyanosis, clubbing, oredema.GENITOURINARY: not examined.NEUROLOGIC: awake and alert, flat affect, quiet, cranial nerves II-XII grossly intact,grossly normal strength and tone, patellar tendon reflexes normal.SKIN: no rashes, mottling, jaundice, or unusual birthmarks

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Differential Diagnosis?

Differential for this 16 year old male withsyncope, diaphoresis, and altered

mental status?

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Differential Diagnosis

Cardiovascular Vasovagal Syncope

Orthostatic Hypotension

Long QT Syndrome

Brugada Syndrome

Catecholaminergic polymorphic ventricular tachycardia

SVT

WPW

Coronary artery anomalies

Hypertrophic

cardiomyopathy/Dilatedcardiomyopathy

Aortic Stenosis

Bradycardia

Neurologic Seizure (atonic seizure)

Complex migraine

Conversion disorder/ Hysteria

Pulmonology

Hyperventilation Toxicology

Barbituates/Alcohol

TCA

Cocaine

Marijuana

Inhalants

Opiates

Carbon Monoxide

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Patients labs/work-up

Orthostatic vitals: became dizzy withstanding

EKG: NSR w/ non-specific T wave

changes Serum and Urine tox negative

BMP wnl

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So now you meet the patient

You decide to get more historysurrounding the incident

What do you like to do for fun?

Play video games

Actually, his parents just got him a car

recently, but it doesnt run

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So about the car

Hes been working on the car with hisdad, and about an hour before the firstepisode, he had been in the garage

with his dad testing the engine. The garage door was open though.

But then dad left and shut the garagedoor. Patient stayed in the garage for

another 15-20 minutes unattendedwith the engine running before comingin for dinner.

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So you order this test

Carboxyhemoglobin:

8.2%!

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Carbon Monoxide Poisoning:

Epidemiology Colorless, odorless,

non-irritating gascreated by incompleteburning ofcarbonaceous fossil

fuels Same density as air

equal distribution inenclosed area

3rd leading cause ofaccidental poisoning inUS >2000 deaths annually

15,000 40,000 non-fatal cases annually

Common sources: Smoke inhalation

Heating systems

Poorly ventilated fuel-

burning devices Camping stoves

Charcoal grills

Fires

Underground electrical

fires (think aftermathof hurricane)

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Carbon Monoxide Poisoning:

Pathophysiology Gas inhaled, then rapidly diffuses across

pulmonary capillary bed to bindhemoglobin

240x higher affinity for hemoglobin thanoxygen, changes hemoglobin shape Impaired oxygen binding to Hb

Decreased oxygen delivery to tissues

Left shifted oxyhemoglobin dissociationcurve (Haldane effect) Favors Hb holding onto O2

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Carbon Monoxide Poisoning:

Pathophysiology Population and organ with high

metabolic needs affected worse

Infants, elderly

Brain, heart, lungs

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Carbon Monoxide Poisoning:

Common Presentations Winter

More indoor exposures

Post-storms and power outages Increased use of generators

Non-specific symptoms Fatigue, dizziness, headache, nausea, irregular breathing,

dyspnea on exertion, palpitations, irritability, confusion,irrational behavior, pallor, cyanosis

Lethargy and syncope more common in children

Chronic headache

Low level chronic exposure Flu-like illness

HA, myalgias NO FEVER

Similar sxs in family members

Recently deceased pet from unknown causes

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Management

Carboxyhemoglobinlevel

Treatment

Mild to Moderate >10% 100% normobaric O2

Severe >40%; or coma,

arrhythmia, sz regardless

of level

Hyperbaric oxygen

therapy

Diagnose with carboxyhemoglobin level >10% Co-oximetry also being used

Treat until carboxyhemoglobin < 5%

Carboxyhemoglobin level does not correlate with clinical severity,outcome, or response to therapy

Used to confirm exposure

Carbon Monoxide Half-Life

Room Air: 4-5 hours

100% normobaric O2: 1 hr

Hyperbaric O2 (2-3 atm): 30 minutes

Studies promising that hyperbaric oxygen therapy for severe poisoningmay preserve neurologic

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Education

Avoid repeat exposures

Carbon monoxide alarms

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Long Term Sequelae

Incidence varies 12% - 74% Most common: cognitive, personality

changes, and parkinsonism

Other long term sequelae: Memory loss, confusion, ataxia, incontinence,

emotional lability, hallucinations, personalitychanges, blindness

May develop at initial exposure andpersist, or after asymptomatic period Asymptomatic period ranges 3-21 days (or

longer)

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References

Kind, Terry. In Brief: Carbon Monoxide.Pediatrics in Review Vol. 26 No. 4 April1, 2005. pp. 150 -151

John L. Green, Michael Shannon,Frederick H. Lovejoy, Jr and CatherineDeAngelis. Index of Suspicion. Pediatricsin Review1992;13;295

Shannon: Haddad and WinchestersClinical Management of Poisoning andDrug Overdoses, 4th ed.