What are the high-yield points for clinical practice in regards to abdominal pain (acute abdomen)?

From the Guidelines

When evaluating abdominal pain in clinical practice, start with a thorough history and physical examination to narrow your differential diagnosis, as recommended by the American College of Physicians 1. Characterize the pain by location, quality, radiation, timing, and associated symptoms. Red flags requiring immediate attention include severe pain, peritoneal signs, hypotension, fever above 38.5°C, persistent vomiting, and signs of GI bleeding. Laboratory tests should include CBC, comprehensive metabolic panel, lipase, and urinalysis, with imaging selected based on clinical suspicion—ultrasound for biliary disease or gynecological concerns, CT for suspected appendicitis or diverticulitis, as supported by the ACR Appropriateness Criteria 1. For pain management, avoid opioids when possible; use acetaminophen 1000mg every 6 hours or NSAIDs like ibuprofen 400-600mg every 6-8 hours for mild to moderate pain. Treat specific conditions appropriately: PPI therapy for peptic ulcer disease (omeprazole 20mg daily), antibiotics for diverticulitis (ciprofloxacin 500mg BID plus metronidazole 500mg TID for 7-10 days in uncomplicated cases), and surgical consultation for appendicitis or bowel obstruction. Serial examinations are crucial for patients with undifferentiated abdominal pain, as evolving symptoms and signs often clarify the diagnosis. Remember that elderly patients and immunocompromised individuals may present atypically with minimal pain despite serious pathology, necessitating a lower threshold for advanced imaging and intervention, as highlighted in the WSES guidelines for management of intra-abdominal infections 1.

Some key points to consider in clinical practice include:

• The use of CT imaging for diagnostic uncertainty in patients with suspected acute left-sided colonic diverticulitis, as recommended by the American College of Physicians 1.
• The management of most patients with acute uncomplicated left-sided colonic diverticulitis in an outpatient setting, with select patients initially managed without antibiotics, as suggested by the ACP guideline 1.
• The importance of clinical judgment in deciding when to use imaging and when to start antibiotics, taking into account individual patient circumstances and the risk of potential harms.
• The need for a step-up approach for diagnosis, from clinical and laboratory examination to imaging examination, tailored to the hospital's resources, as recommended by the WSES guidelines 1.

In terms of specific treatments,

• antibiotics may not be necessary for select patients with acute uncomplicated left-sided colonic diverticulitis, as suggested by the ACP guideline 1.
• CT imaging can be useful in diagnosing diverticulitis, especially when the diagnosis is uncertain, as supported by the ACR Appropriateness Criteria 1 and the WSES guidelines 1.
• serial examinations are crucial for patients with undifferentiated abdominal pain, as evolving symptoms and signs often clarify the diagnosis.

Overall, the management of abdominal pain requires a thorough and individualized approach, taking into account the patient's specific symptoms, medical history, and risk factors, as well as the latest evidence-based guidelines and recommendations 1.

From the Research

Clinical Approach to Abdominal Pain

• The evaluation of abdominal pain requires consideration of a broad differential diagnosis, including gastroenteritis, nonspecific abdominal pain, cholelithiasis, urolithiasis, diverticulitis, and appendicitis 2
• Extra-abdominal causes such as respiratory infections and abdominal wall pain should also be considered in the diagnosis of abdominal pain 2
• A systematic approach to evaluating abdominal pain is essential to providing patients with efficient and accurate care, and accounts for 5% to 10% of all presentations in the emergency department 3

Diagnostic Tests and Imaging

• Recommended tests for abdominal pain may include a complete blood count, C-reactive protein, hepatobiliary markers, electrolytes, creatinine, glucose, urinalysis, lipase, and pregnancy testing 2
• Imaging studies are chosen based on the location of pain and index of suspicion for specific etiologies, with computed tomography with intravenous contrast media often chosen for generalized abdominal pain, left upper quadrant pain, and lower abdominal pain 2
• Ultrasonography is the study of choice for right upper quadrant pain, and point-of-care ultrasonography can aid in the prompt diagnosis of several etiologies of acute abdominal pain, including cholelithiasis, urolithiasis, and appendicitis 2
• Laboratory tests, such as those highlighted in 4, can be used to narrow the differential diagnosis based on the patient's history and examination

Special Considerations

• In patients who have female reproductive organs, diagnoses such as ectopic pregnancy, pelvic inflammatory disease, and adnexal torsion should be considered 2
• If ultrasonography results are inconclusive in pregnant patients, magnetic resonance imaging is preferred over computed tomography when available 2
• Unstable patients with abdominal pain require timely intervention to limit morbidity and mortality, and clinicians must consider multiple diagnoses, especially those life-threatening conditions 5