The Acute Abdomen

Samuel Hamner GayUMMC School of Medicine

Surgical Clerkship

• Sudden nontraumatic disorder of the abdomen for which urgent operation may be necessary

• Goal of acute abdomen H/P:– Diagnose or at least and most importantly determine if

the acute abdomen is a life-threatening surgical emergency or indolent medical condition

The Acute Abdomen

The most common causes of the Acute Abdomen

For adults:• Appendicitis• Bowel obstruction • Acute vascular condition• Cancer• Cholecystitis

For children:• Appendicitis (1/3)• Nonspecific abdominal pain (2/3)

Other causes of the Acute Abdomen

• Can be caused by disorders within organs outside the abdominal cavity:– lower lobe pneumonia, inferior MI, bursitis and

hip joint disorders, thoracic radiculopathy, and a variety of pelvic disorders

Abdominal Pain

Visceral pain

• Afferent C fibers innervating walls of hollow organs or capsules of solid organs

• Stimulated by distention, inflammation, ischemia

• Generally dull, poorly localized, mild to moderate pain

• Most often felt in midline• Pt constantly moving• Not aggravated by coughing• Its usually the first type of pain felt in an

AA• May be more indicative of a medical

condition

Parietal pain

• Afferent C and A delta fibers innervating the parietal peritoneum

• Stimulated by pus, bile, urine, GI secretions

• A delta fibers are responsible for the more acute, sharper, localized severe pain

• Pt doesn’t want to move• Aggravated by coughing/breathing• Rectus muscle rigidity (aka Guarding)• May be more indicative of a surgical

acute abdomen

Visceral Pain

Colic Pain

• Type of visceral pain• Defined as pain with pain-free intervals reflecting intermittent

peristalsis• Sharp or dull intermittent pain

– Sharp colicky pain: ureters or uterine tube obstruction– Dull colicky pain: bowel obstruction

• Caused by the obstruction of a visceral conduit like the intestine, ureters, uterine tubes

• “Biliary colic” is not colicky pain– The gallbladder and bile duct, in contrast to the intestine and

ureters, do not have peristaltic movements

Referred Pain

• Type of parietal pain• Due to the confluence of afferent fibers w/in

the posterior horn that innervate separate cutaneous areas

• Example: Shoulder pain– Subdiaphragmatic irritation by air and/or blood in

peritoneal fluid is referred to the shoulder via C4 mediated phrenic nerve

Shifting Pain

• Pain that changes location overtime, paralleling the coarse of the underlining condition

• Example: Acute Appendicitis– Begins with visceral pain within the peri-umbilical

area followed by parietal pain within the RLQ

Referred and Shifting Pain

Location, onset, and character of pain

Abdominal Pain

Sharp, superficial, constant pain is most likely caused by which of the following?a) Small bowel obstructionb) Large bowel obstructionc) Perforated ulcerd) Kidney stone

Abdominal Pain

Intermittent, vague, deep-seated, dull crescendo pain is most likely due to which of the following?a) Kidney stoneb) Small bowel obstructionc) Ruptured appendixd) Ruptured ovarian cyst

Abdominal Pain

Unbearably intense, sharp, intermittent pain is most likely due to which of the following?a) Cholecystitisb) Large bowel obstructionc) Ruptured ectopic pregnancyd) Non-ruptured ectopic pregnancy

Abdominal Pain

No pain w/ a vague feeling of abdominal fullness that feels like it could be relieved by a bowel movement is most likely caused by which of the following?a) Cholecystitisb) Pancreatitisc) SBOd) Retrocecal appendicitis

Gas Stoppage Sign

• Abdominal fullness that feels as though it could be relieved by a bowel movement

• Sign of reflex ileus caused by inflammatory process– Most commonly retrocecal or retroileal

appendicitis

Vomiting

• Did the vomiting occur before or after the onset of pain?– Pain before vomiting: surgical condition– Vomiting before pain: medical condition

• Did the vomiting come before or after nausea?– Prolonged nausea before vomiting may be an indication

for LBO

Vomiting

• Appearance helps indicate the location of an obstruction

• What does it look like?– Green – SBO– No green – Pyloric Stenosis– Feculent material – LBO

Constipation

Constipation• Constipation is the absence of

passage of stool• Post-surgical constipation is

most likely reflex ileus induced by visceral afferent fibers stimulating efferent splanchnic nerves

• Not an indicator of intestinal obstruction

Obstipation• Absence of passage of both stool

and gas• Strongly suggest bowel

obstruction, especially if there is painful abdominal distention or repeated vomiting

Diarrhea

• Usually an indicator of a medical cause of an acute abdomen:– Non-blood-stained diarrhea: • Gastroenteritis

– Blood-stained diarrhea: • dysentery, ulcerative colitis, Crohn’s disease• SURGICAL CAUSE OF BLOOD STAINED DIARRHEA =

ISCHEMIC COLITIS

Bloody Diarrhea and RUQ pain w/ a Hx of Travel

Other Specific Symptoms

• Jaundice• Hematemesis• Melena• Hematochezia• Rectorrhagia • Hematuria• Passage of blood clots

Other relevant aspects of the History

• Gynecological Hx– Menstrual Hx

• Drug Hx– Anticoagulants – retroperitoneal and intramural duodenal and

jejunal hematomas– Oral contraceptives – mesenteric venous infarction and benign

hepatic adenomas– Corticosteroids – mask signs of advanced peritonitis– Crack smoking – pyloric perforation

• Family Hx• Travel Hx• Surgical Hx

Physical Exam

• General observation• Systemic signs– Tachycardia and diaphoresis– Fever• Low-grade

– Inflammatory conditions (polyarthritis nodosa, UC, Crohn’s)

• High grade– Severe infections

• Abdominal exam

Abdominal exam• Inspection• Auscultation• Cough Tenderness• Percussion• Guarding or rigidity• Palpation

– Light palpation– Deep palpation– Rebound tenderness– Punch tenderness

• Costal area• Costovertebral area

• Special tests/signs• Rectal and pelvic examination

Inspection

• Distention – SBO, LBO, or Ileus• Scaphoid – Perforated Ulcer• Cullen Sign – Intraperitoneal Hemorrhage• Grey Turner Sign - Intraperitoneal Hemorrhage

Auscultation

• Mostly useless due to the many variant noises of any given abdominal disorder

• Strong peristaltic rushes synchronous w/ colic = Early SBO• Silent abdomen = LATE SBO• High-pitched hyperperistaltic sounds = enteritis

Cough Tenderness

• Tests for presence and severity of parietal pain• Important preliminary test if pt is in severe

abdominal pain

Percussion

• Assess size of liver• Test for shifting dullness• Test for midline tympany

Palpation

• Begin away from area of pain• Test for Guarding – Voluntary spasm – Involuntary spasm • only caused by peritoneal inflammation and, for

unknown reasons, renal colic

• Parietal pain is aggravated by touch, therefore this most be performed gently and slowly

Special Tests/Signs

• Carnett’s Sign• Murphy’s Sign• Psoas Sign• Obturator Sign

Pelvic Examination

• Crucial in women with– discharge, dysmenorrhea, menorrhagia, or LLQ

pain• Young women w/ an acute abdomen have the

highest risk for an incorrect diagnosis

Investigative Studies

• H/P provides the diagnosis in 2/3 of acute abdomen cases

Which of the following is the best method of confirming a perforated peptic ulcer?a) Barium swallowb) Leukocytosisc) Upper endoscopyd) Upright abdominal radiographe) Colonoscopy

Which of the following is the best test to diagnose cholecystitis?a) Abdominal radiographb) Ultrasound of abdomenc) Dimethyl iminodiacetic acid (HIDA) scand) MRI of abdomene) Upper endoscopy

Pancreatitis

• Severe abdominal pain that radiates to back, accompanied by vomiting

• The addition of peritoneal signs and Cullen sign – Necrotizing pancreatitis

• Cloudy (lactescent) serum in a pt w/ abdominal pain– Pancreatitis even if serum amylase is normal

• Small and large bowel dilation w/ diffuse gas pattern w/ air outlining the rectal ampulla is suggestive of Paralytic Ileus

• Dilated small bowel loops w/ air-fluid levels along w/ absence or minimal colonic gas is suggestive of SBO

• Distended Cecum w/ small bowel dilation and absence of air within the rectum is suggestive of LBO

• Free gas under the hemidiaphragm is suggestive of Perforated Peptic Ulcer

Specific findings in chest and abdominal X-rays

Summary

• The variety of acute abdominal presentations and the frequency at which they present atypically can make a diagnosis challenging

• The H/P is the most valuable tool that a physician can use when managing an acute abdomen workup, yet interpretive studies can help establish a diagnosis, especially in atypical presentations

• The ability to recognize a life-threatening acute abdomen is a vital skill that can be done using one’s knowledge of abdominal pain and other acute abdominal symptoms