What are the latest guidelines for a per abdomen (abdominal) examination?

Latest Guidelines for Per Abdomen Examination

The most effective abdominal examination should follow a systematic approach with specific techniques for each component, supported by appropriate imaging studies when indicated, with CT scan being the preferred imaging modality for suspected abdominal pathology.

Preparation and Examination Techniques

• Have the patient empty their bladder before examination when possible to improve accuracy of findings 1
• Position the patient supine with arms at sides and knees slightly flexed to relax abdominal muscles 1
• Ensure proper exposure of the abdomen from xiphoid process to symphysis pubis while maintaining patient dignity 1
• Document all findings systematically, including location and characteristics of any abnormalities 1

Systematic Approach to Abdominal Examination

Inspection

• Observe for abdominal distension, visible peristalsis, pulsations, skin changes, surgical scars, and asymmetry 2
• Note any signs of peritonitis including guarding, rebound tenderness, or rigidity which may indicate perforation 2
• Be aware that clinical examination may be unreliable in patients with excess skin or flaccid abdomen (such as post-bariatric surgery patients) 2

Auscultation

• Listen for bowel sounds in all four quadrants, noting character, frequency, and pitch 2
• Absent bowel sounds may suggest peritonitis or ileus 2
• Hyperactive, high-pitched bowel sounds may indicate early bowel obstruction 2

Percussion

• Percuss all four quadrants to detect abnormal fluid, masses, or organomegaly 2
• Shifting dullness and fluid thrill should be assessed when ascites is suspected 2
• Percussion can help identify tympany associated with bowel distension or pneumoperitoneum 2

Palpation

• Begin with light palpation away from areas of reported pain, progressing to deeper palpation 2
• Assess for masses, organomegaly, tenderness, guarding, and rebound tenderness 2
• Perform special maneuvers as indicated (Murphy's sign, psoas sign, obturator sign) 2
• Digital rectal examination should be performed when indicated, especially for suspected lower GI pathology 2

Laboratory Assessment

• Complete blood count, electrolytes, liver enzymes, and inflammatory markers (ESR, CRP) are mandatory in assessing acute abdomen 2
• Serum albumin and pre-albumin help assess nutritional status and degree of inflammation 2
• In suspected infectious causes, rule out Clostridium difficile and Cytomegalovirus 2
• Leukocytosis, neutrophilia, elevated amylase levels, and lactic acidosis may suggest perforation or necrosis 2

Imaging Studies

Initial Imaging Selection

• CT scan with IV contrast is the recommended primary imaging study for suspected abdominal pathology, with superior sensitivity (93-96%) and specificity (93-100%) 2, 3
• Abdominal ultrasound can be used as a screening test with moderate sensitivity (88%) when CT is unavailable 2, 3
• Plain abdominal X-rays have limited sensitivity (74-84%) and specificity (50-72%) and should only be used when other modalities are unavailable 2, 3

Specific Clinical Scenarios

• For suspected bowel obstruction: CT scan is preferred; if unavailable, water-soluble contrast enema is a valid alternative 2, 3
• For suspected perforation: CT scan is recommended for stable patients; however, if there are clear signs of diffuse peritonitis, CT should not delay appropriate treatment 2
• For pregnant patients: Ultrasound and MRI are recommended to limit radiation exposure 2
• For suspected appendicitis: Helical CT of abdomen and pelvis with intravenous contrast is recommended 2

Imaging Considerations in Special Populations

• In bedridden patients who cannot stand, a left lateral decubitus radiograph should be performed in addition to the supine radiograph to evaluate for pneumoperitoneum and air-fluid levels 4
• For female patients of childbearing potential, pregnancy testing should be performed prior to imaging with ionizing radiation 2
• In pregnant women, ultrasound and MRI are preferred; low-dose CT can be used in selected cases 2

Common Pitfalls and Caveats

• Do not delay surgical exploration if there is a high index of clinical suspicion and alarming clinical signs/symptoms, even with negative radiological assessment 2
• Clinical examination may be unreliable in post-bariatric surgery patients due to excess skin and flaccid abdomen 2
• CT scan, even when readily available, should never expose the patient to unsafe delays in appropriate treatment for conditions requiring immediate intervention 2
• Be aware that 20-30% of plain abdominal X-rays may be inconclusive in cases of abdominal pathology 3
• Early involvement of a surgeon is required in cases of suspected perforation 2