Acute Abdominal Pain


  1. Visceral
  2. Somatic
  3. Referred pain


Perforation Obstruction Inflammation
- Sudden Onset
- Very Severe, Generalized
- Pt does not move, tries to stay still because moving around causes pain.
- Sudden Onset
- Colicky pain: (comes & Goes)
- Localized & Radiates
- Pt. moves all the time, looking for a position where he can be comfortable.
- Gradual onset
- Constant pain
- Localized & Radiates
- Fever & Leukocytosis.
Physical Exam:
- Peritoneal irritation
- Rebound tenderness
- NO bowel sounds
- Localized to the area of trouble. - Localized to the area of trouble & radiates
1. Pneumonia* = CXR
2. MI = CE, EKG
3. Pancreatitis = Amylase/Lipase

 - CT abd/pelvis w/ contrast

1. Ureteral stone = CT w/o contrast
2. Volvulus: usually in very old pt w/ abd pain. "Bird beak" on ABX.
1. Pancreatitis (Acute): Amylase/Lipase
2. Acute Cholecystitis: RUQ Ultrasound
3. Acute Diverticulitis*: CT abd/pelv w/ contrast
4. Ascites: Culture of ascitic fluid. High risk of SBP

Acute abdominal pain   PLUS    Very OLD pt.
Sigmoid Volvulus Mesenteric Ischemia
- RUQ pain
X-Ray: Parrot's beak, Air-fluid level
- Obstructive symptoms

-GI consult
- Old pt. w/ Hx of A-Fib or MI

Dx: CT Angio

-Avoid digoxin, beta-blocker, pressors
-Surgical Consult

Abdominal Pain by Symptoms

Grouping of Known Abdominal Diseases by Symptoms
Pain/vomiting/± rigidity Pain/vomiting/
Pain (± vomiting)
Acute pancreatitis Bowel obstruction Acute diverticulitis
Diabetic gastric paresis Cecal volvulus Adnexal torsion
Diabetic ketoacidosis   Mesenteric ischemia
Incarcerated hernia   Myocardial ischemia*
    Testicular torsion
Pain/shock Pain/shock/rigidity Distention (± pain)
Abdominal sepsis Perforated appendix Elderly with bowel obstruction/volvulus
Aortic dissection Perforated diverticulum  
Hemorrhagic pancreatitis Perforated ulcer  
Leaking/ruptured abdominal aortic aneurysm Ruptured esophagus  
Splenic rupture  
Mesenteric ischemia (late)    
Myocardial ischemia*    
Ruptured ectopic pregnancy    


Suggested Laboratory Studies for Goal-Directed Clinical Testing in Acute Abdominal Pain
Laboratory Test Clinical Suspicion
Amylase Pancreatitis (if lipase not available)
Lipase Pancreatitis
ß-HCG Pregnancy
Ectopic or molar pregnancy
Coagulation studies (prothrombin time/partial thromboplastin time) GI bleeding
End-stage liver disease
Electrolytes Dehydration
Endocrine or metabolic disorder
Glucose Diabetic ketoacidosis
Gonococcal/chlamydia testing Cervicitis/urethritis
Pelvic inflammatory disease
Hemoglobin GI bleeding
Lactate Mesenteric ischemia
Liver function tests Cholecystitis
Platelets GI bleeding
Renal function tests Dehydration
Renal insufficiency
Acute renal failure
Urinalysis Urinary tract infection

Common Dx for Acute Abd. Pain

Diagnosis Potential Threat to Life Epidemiology Typical Location Typical Radiation Typical Quality Helpful Cautions Laboratory Imaging Complications Mngt
Appendicitis Urgent Peak age:
adolescence and young adulthood
Early: periumbilical; late: RLQ. If retrocecal or third trimester pregnancy may be RUQ - Initially dull, becomes severe RLQ pain; pain migrated from periumbilical area;
pain before vomiting 100% sens, 66% spec; rigidity
Anorexia: 84% sens; vomiting 50% sens; fever: 67% sens; elevated WBC: 70%–90% sens No single test is highly sensitive or specific;
C-reactive protein may be helpful
CT preferred in adults and nonpregnant women Perforation Surgery
Biliary colic - F >> M before age 60 y old, Hispanic > white > black RUQ > epigastric Right subscapular area Initially colicky, becomes continuous; colic typically resolves <6 h Bloating and dyspepsia are not related to gallstones - Suspect common bile duct stone if elevated bilirubin US: 86%–96% sens, 78%–98% spec Cholecystitis ? Surgery
Bladder outlet obstruction - Benign prostatic hypertrophy Suprapubic - - - - - Bedside US -  
Bowel obstruction Urgent History previous abdominal surgery Diffuse - Colicky Vomiting, distention - - Plain films: 77% sens; 93% CT sens Incarceration, strangulation NPO, Surgery
Cholecystitis Urgent Most common surgical cause of abdominal pain in elderly RUQ > epigastric Right subscapular area Continuous (+) Murphy sign increases likelihood of cholecystitis (odds ratio 2.3–2.8); jaundice suggests obstruction Up to 90% afebrile; elevated WBC only 63% sensitive and 57% specific. Cholangitis: elevated WBC only 80% sensitive. No single test can exclude diagnosis;
aspartate aminotransferase/
alkaline phosphatase each only 70% sens and 42% spec
US: 91% sens; hepatobiliary iminodiacetic acid scan: 97% sens, 90% spec Common bile duct obstruction; ascending cholangitis; gangrene Cholecystectomy (Surgery)
Diverticulitis - M > F before age 40 y old; incidence increases with age Sigmoid (85%): LLQ ; cecal/Meckel: RLQ - - 50% report previous episode of similar pain Temperature may be normal; 25% (+) fecal occult blood WBC may be normal CT: sens 93%–100%; spec 100% Perforation; abscess; fistula; obstruction Cipro + Flagyl
Epiploic appendagitis - Middle age; M > F LLQ - - Fever unusual; n/v infrequent; diarrhea 25% In general, pts are not systemically ill - CT -  
Mesenteric arterial occlusion Emergent Atrial fibrillation Any - Severe Pain out of proportion to physical findings; nausea: 56%–93%; vomiting: 38%–80%; diarrhea: 31%–48% Atrial fibrillation Lactate: 75%–90% sens; not specific; elevated WBC: 90% Selective CT angiography: 96% sens Metabolic acidosis Surgery
Mesenteric venous thrombosis - Hypercoagulable states, liver disease Most commonly: generalized or epigastric - - - - - Contrast-enhanced CT -  
Mesenteric ischemia (nonocclusive) - Critically ill pts; vasoactive drugs - - - - - - Angiography -  
Myocardial ischemia Emergent - Upper midline - Steady, dull Abnormal ECG ECG may be normal Troponin: 80% sens at 4 h from symptom onset - - CATH?
Pancreatitis Urgent M > F. Risks: alcohol; biliary disease; drugs; endoscopic retrograde cholangio-pancreatography Epigastric Back Severe, constant Nausea and vomiting common May have low-grade fever Lipase: 90% sens first 24 h US may show edema; CT: 78% sens, 86% spec Hemorrhage; pseudocyst; adult respiratory distress syndrome; sepsis NPO, Pain control
PID - Sexually transmitted diseases; prior PID; multiple partners RLQ and/or LLQ - - Vaginal discharge; dyspareunia; cervical motion tenderness Fever not necessary for diagnosis Elevated WBC not necessary for diagnosis - Tubo-ovarian abscess; perihepatitis; infertility; ectopic pregnancy; chronic pain Cefotetan 2g IV q12h
Doxycycline 100mg IV q12h, then 100mg po bid to complete 14 days
Peptic ulcer disease - Peak age: 50s; M > F; chronic aspirin or NSAIDs; smoking; alcohol; Helicobacter pylori Epigastric - Severe, persistent Vomiting, tachycardia Nonulcer dyspepsia more likely if: age <40 y old, no weight loss, no night pain, no vomiting - - Perforation; bleeding EGD, PPI/H2 Blocker
H. Pylori Testing
Perforated viscus Urgent - Any - Severe - - - Upright chest x-ray: 80% sens for free air - Surgery
Ovarian torsion Urgent - RLQ or LLQ Back, flank, or groin Sudden onset, severe, sharp; may have nausea/vomiting Adnexal mass - - Pelvic US with Doppler flow Ovarian salvage decreases with delay in diagnosis Surgery
Renal/ureteral colic - Average age: 30–40 y old; white > black; family history of stones Right or left flank Ipsilateral groin/
Severe; colicky; nausea and vomiting common 85%–90% have hematuria; only 30% have gross hematuria - Urinalysis Spiral CT Obstruction; infection Pain control, Flomax, Lithotrypsy?
Ruptured ectopic pregnancy Immediate Previous ectopic; PID; infertility treatment; intrauterine device <1 y; tubal surgery RUQ or LLQ - Sudden onset; severe pain Pelvic mass Pelvic exam may be normal Pregnancy test Transvaginal US Shock Surgery
leaking abdominal aortic aneurysm
Immediate Older; male; atherosclerotic cardiovascular disease; smoker; (+) family history Mid-abdomen or flank Back, groin, or thigh Severe; sudden onset; constant Pulsatile mass detected: 22%–96% sens Only 50% are hypotensive at presentation. Normal pulses do not exclude diagnosis - Bedside US 100% sens Shock SCREWED
Tubo-ovarian abscess Urgent PID Unilateral or bilateral pain - - - Fever may be absent Leukocytosis may be absent - Rupture, peritonitis, shock  

Abbreviations: > = more than; >> = much more than; < = less than; + = positive; F = female; LLQ = left lower quadrant; M = male; n/v = nausea and vomiting; PID = pelvic inflammatory disease; pts = patients; RLQ = right lower quadrant; RUQ = right upper quadrant; sens = sensitivity; spec = specificity; WBC = white blood cell count.


ED care & Disposition

Unstable pt. should be resuscitated immediately, then diagnosed clinically with emergent surgical consult.

  1. Most common resuscitation need for abdominal pain pt. is IV hydration w/ NS. During the initial evaluation, the pt. should be NPO.
  2. Judicious use of analgesics is appropriate & may facilitate the ability to obtain a better Hx & more accurate PE.
    • Morphine 0.1 mg/kg IV (reverse w/ naloxone 0.4mg IV)
    • NSAID (Toradol 60mg IV/IM) in pt w/ renal colic.
  3. Antiemetic increase pt. comfort level & facilitate assessment of pt's s/s
    • Zofran 4mg IM/IV
    • Reglan 10mg IM or slow IV
  4. When appropriate, ABx Tx should be initiated, depending on the suspected source of infection.
Antibiotic Comments
Aminoglycosides Traditional therapy, if no reluctance for use of aminoglycoside; often selected for sicker, older, immunocompromised, or hypotensive patients
Gentamicin or tobramycin, 1.5 mg/kg IV q 8 h
Amikacin, 5 mg/kg IV q 8 h
Metronidazole, 1 g IV followed by 500 mg IV q6h
Clindamycin, 900 mg IV q8h
Second-generation cephalosporins Often selected for those less ill
Cefoxitin, 2 g IV q6h
Cefotetan, 2 g IV q6h
Ampicillin-sulbactam, 3 g IV q6h
Ticarcillin-clavulanate, 3.1 g IV q6h
Piperacillin-tazobactam, 3.3 g IV q6h Piperacillin-tazobactam often selected for suspected biliary sepsis
Imipenem-cilastatin, 1 g IV q6h
Aztreonam, 2 g IV q6h maximum dose For patients with allergy to penicillins or cephalosporins
Clindamycin or metronidazole (see above for dosages)
Ceftriaxone, 2g IV q12h maximum dose For spontaneous bacterial peritonitis, coverage for Pneumococcus as well as Escherichia coli
Cefotaxime, 2 g IV q4h
  1. Surgical or obstetric & gyn consult should be obtained for pts with suspected acute abdominal or pelvic pathology requiring immediate intervention, including, but not limited to, abdominal aortic aneurysm, intraabdominal hemorrhage, perforated viscus, intestinal obstruction or infarction, & ectopic pregnancy. Historically, the "acute abdomen" or "surgical abdomen" has been identified by the presence of pain, guarding, & rebound as indicating a likely need for emergent surgery.
  2. Indications for admission include:
    • Toxic appearance
    • unclear diagnosis in elderly or immunocompromised pt,
    • inability to reasonably exclude seious etiology,
    • intractable pain or vomiting,
    • AMS, & inability to follow discharge or follow-up instructions.
    • continued observation with serial examinations is an alternative.
  3. Many patients with nonspecific abdominal pain can be discharged safely with 24 hr of follow-up and instructions to return immediately for increased pain, vomiting, fever or failure of symptoms to resolve.