Acute abdominal pain may be due to numerous etiologies including gastrointestinal, genitourinary, cardiovascular, pulmonary, musculoskeletal, dermatologic, neurogenic, and other sources creating visceral, parietal, or referred pain to the abdomen.
Consider immediate life threats that might require emergency intervention. Elicit time of pain onset; character, severity, location of pain and its referral (Fig. 35-1); aggravating and alleviating factors; and similar prior episodes. Cardiorespiratory symptoms, such as chest pain, dyspnea, and cough; genitourinary symptoms, such as urgency, dysuria, and vaginal discharge; and any history of trauma should be elicited. In older patients it is also important to obtain a history of myocardial infarction, dysrhythmias, coagulopathies, and vasculopathies. Past medical and surgical histories should be elicited, and a list of medications, particularly steroids, antibiotics, or nonsteroidal anti-inflammatory drugs (NSAIDs), should be noted. A thorough gynecologic history is indicated in female patients.
Differential diagnosis of acute abdominal pain by location. AKA, alcoholic ketoacidosis; DKA, diabetic ketoacidoisis; LLL, lower left lobe; RLL, right lower lobe.
Reproduced with permission from Fitch M. Utility and limitations of laboratory studies, in Cline DM, Stead LG (eds), Abdominal Emergencies
. New York: McGraw-Hill Medical; 2008, p. 19.
The physical examination should include the patient's general appearance. Patients with peritonitis tend to lie still. The skin should be evaluated for pallor, jaundice, or rash. The vital signs should be reviewed for signs of hypovolemia due to blood loss or volume depletion. Due to medications and/or the physiology of aging, elderly patients may not exhibit tachycardia in the face of hypovolemia or illness. A core temperature should be obtained; however, absence of fever does not rule out infection, particularly in the elderly. The abdomen should be inspected for contour, scars, peristalsis, masses, distention, and pulsation. The presence of hyperactive or high-pitched or tinkling bowel sounds increases the likelihood of small bowel obstruction.
Palpation is the most important aspect of the physical examination. The abdomen and genitals should be assessed for tenderness, guarding, masses, organomegaly, and hernias. Rebound tenderness, often regarded as the clinical criterion standard of peritonitis, has several important limitations. In patients with peritonitis, the combination of rigidity, referred tenderness, and, especially, cough pain usually provides sufficient diagnostic confirmation; false-positive rebound tenderness occurs in about one patient out of four without peritonitis. This has led some investigators to conclude that rebound tenderness, in contrast to cough pain, is of no predictive value. A useful and underused test to diagnose abdominal wall pain is the sit-up test, also known as the Carnett sign. After identification of the site of maximum abdominal tenderness, the patient is asked to fold his or her arms across the chest and sit up halfway. The examiner maintains a finger on the tender area, and if palpation in the semisitting position produces the same ...