1. The Acute Abdomen
Jason E. Davis, MD

2. Abdominal Pain A leading cause for hospital admissions
Most self-limited and of little consequence
Subset of serious acute pathology may require acute medical and/or surgical intervention
This latter group referred to as ‘acute abdomen’
Not all acute abdomens = surgical abdomen
Renal colic, gastroenteritis, infectious colitis*, PID
Mesenteric ischemia, ruptured AAA, appendicitis, perforated bowel, perf’d peptic ulcer, inc’d hernia

3. Broad Differential Dx

4. Anatomic Considerations
Embryonic origin & Blood supply
Foregut: esophagus, stomach, proximal duodenum, pancreas, liver, biliary tract, spleen
Celiac artery
Midgut: distal duodenum, jejunem, ileum, cecum, appendix, proximal 2/3 transverse colon
Superior mesenteric artery
Hindgut: remaining colon and rectum
Inferior mesenteric artery

5. Anatomic Considerations
Innervation
Visceral pain: autonomic, dull, cramping, poorly localized, often assoc with nausea and diaphoresis
Often midline secondary to embryonic origin
Parietal pain: somatic, sharp, severe, persistent, loc
Referred visceral sensation
Foregut pain: Epigastric
Midgut pain: Peri-umbilical
Hindgut pain: Hypogastrium

6. Anatomic Considerations

7. Anatomic Considerations

8. Approach to Acute Abdomen
Age
Location and character of pain
Pain duration and progression
Associated symptoms
Nausea
Emesis
Anorexia
Constipation/Diarrhea

9. Approach to Acute Abdomen
Most important symptom is PAIN. Accordingly, history should include all of the following:
1. Onset
2. Severity
3. Type of pain
4. Radiation of pain
5. Change in nature of pain
6. Associated bowel or urinary symptoms
7. Aggravating or relieving factors

10. Approach to Acute Abdomen
Diagnosis according to onset of pain:
Sudden
Rapid
Gradual
Chronic
(exacerbation)
Sudden onset (full pain in seconds) Perforated ulcer Mesenteric infarction Ruptured AAA Ruptured ectopic pregnancy Ovarian torsion or ruptured cyst Pulmonary embolism Acute myocardial infarction
Rapid onset (initial sensation to full pain over minutes or hours) Strangulated hernia Volvulus Intussusception Acute pancreatitis Biliary colic Diverticulitis Ureteral and renal colic
Gradual onset (hours) Appendicitis Strangulated hernia Chronic pancreatitis Peptic ulcer disease Inflammatory bowel disease Mesenteric lymphadenitis Cystitis and urinary retention Salpingitis and prostatitis
Stereotypes of Pain Onset and Associated Pathology
Position of patient (motionless vs. writhing in pain vs. rolling restlessly  appendicitis/peritonitis vs. mesentary ischemia vs. ureteral/intestinal colic)

11. Approach to Acute Abdomen
Diaphragmatic
Supraclavicular area (Kehr’s sign)
Ureteral
Hypogastrium, groin, inner thigh
Cardiac pain
Epigastrium, jaw, shoulder
Appendix
Periumbilical via T10 nerve
Duodenum
Umbilical region via greater
thoracic splanchnic nerve
Hiatal hernia
Epigastrium via T7 and T8 nerves
Pancreas or gallbladder
Epigastrium
Gallbladder and bile duct
Epigastric pain, wraps around scapula
Structure irritated
Location of referred pain

12. Named Exam Findings Sign Finding Association Cullen's sign
Bluish periumbilical discoloration
Retroperitoneal hemorrhage (hemorrhagic pancreatitis, abdominal aortic aneurysm rupture)
Kehr's sign
Severe left shoulder pain
Splenic rupture Ectopic pregnancy rupture
McBurney's sign
Tenderness located 2/3 distance from anterior iliac spine to umbilicus on right side
Appendicitis
Murphy's sign
Abrupt interruption of inspiration on palpation of right upper quadrant
Acute cholecystitis
Iliopsoas sign
Hyperextension of right hip causing abdominal pain
Obturator's sign
Internal rotation of flexed right hip causing abdominal pain
Grey-Turner's sign
Discoloration of the flank
Chandelier sign
Manipulation of cervix causes patient to lift buttocks off table
Pelvic inflammatory disease
Rovsing's sign
Right lower quadrant pain with palpation of the left lower quadrant
Sign
Finding
Association

13. Imaging and Laboratory Studies
Laboratory examinations
CBC with differential, type & screen
Chem-10, amylase, LFT’s, urinanalysis
X-rays of the chest and abdomen (upright/supine)
Distended loops of bowel, kidney stones, perf  free gas
Ultrasound: cholelithiasis, bile duct obstruction, AAA
Abdominal CT: AAA, abdominal abscess, severe diverticulitis
Endoscopy: perforated peptic ulcer, SBO, gastric cancer
Colonoscopy: carcinoma of the colon
Angiography: mesenteric ischemia
Radionuclide scans

14. Appendiceal Disease Appendicitis Constipation: “the great imitator”
7% lifetime risk of appendicitis
Most common cause of acute abdominal surgery in the U.S.
Though living in Lehigh Valley appears to be risk for gallbladder disease
Must be considered in every patient with acute abdomen
Especially common during pregnancy (also important to consider ectopic pregnancy in women of reproductive age)
Constipation: “the great imitator”
Less common among differential diagnoses
Mucocele, carcinoid, appendiceal carcinoma

15. Special Considerations
Elderly patients
May not mount febrile response
Atypical pain presentation (severity/location)
Immunosuppressed patients
Opportunistic infections, lymphomas
Corticosteroids may mask pain
Obese patients
May be more difficult to palpate
Patients taking pain medications
Opioids may cause constipation and mask/distort pain
Pregnant women
Distorted abdomen & pregnancy may mimic Sx’s

16. Beyond Appendicitis

17. Beyond Appendicitis Appendiceal Neoplasms Carcinoid
Marjority of appendiceal neoplasms
Derived from neural crest cells
<2cm (90%)  appendectomy
>2cm (10%)  right hemicolectomy
Slow mets, 5 yr survival >50% w/ mets
Primary Adenocarcinoma
Mucinous more favorable than Colonic
Assoc with colon and ovarian CA (15 – 30%)
Lymphoma (often AIDS-associated)

18. Acute Abdomen
Algorhithm adopted from Vanderbilt Medical Center

19. RLQ Pain
Adopted from Vanderbilt Medical Center

20. Case 1: Ms. Jones 27 years old, pregnant female ED presentation
Crampy peri-umbilical pain
Nausea, emesis and anorexia x 12 hours
Pain has ‘migrated’ to RLQ over past several hours, becoming constant and intense
Urinanalysis: mild hematuria and pyuria
CT scan – deferred for preg

21. Case 1: Ms. Jones revisited
Appendicitis
Classic chronologic presentation
Especially common during pregnancy
1 out of every 1750 pregnancies!
May be in RUQ due to enlarged uterus
Mild hematuria and pyuria are common in appendicitis with pelvic inflammation
Radiopaque fecalith present only 5% x’s
Open or Laparoscopic appendectomy

22. Case 2: Mr. Smith 42 year-old male ED presentation
Fever, vomiting and diarrhea
Constant abdominal pain 4hrs, radiates to back
Last bowel movement yesterday, flatus unsure
FUA: non-specific bowel gas pattern

23. Case 2: Mr. Smith revisited
Gastroenteritis
Classic presentation
Pain often follows N/V
Non-surgical, medical management

24. Summary Differential diagnosis for acute abdomen is lengthy
Many presentations will not require admission or surgery
Ischemic colitis, ruptured AAA, intestinal or ulcer perforation, and ectopic pregnancy are important causes not to be missed
Common differentials include appendicitis, cholecystitis, obstruction, and ischemia, but will vary per population

25. Thank you