A vitally stable patient with mild right upper quadrant abdominal pain after a recent road traffic accident (RTA), what is the most appropriate next step?

Abdominal Ultrasound is the Most Appropriate Next Step

For a vitally stable patient with mild right upper quadrant pain after recent road traffic accident, obtain an abdominal ultrasound immediately as the first-line diagnostic test to evaluate for delayed traumatic hepatobiliary injuries. 1

Why Ultrasound is the Correct Choice

The American College of Radiology rates ultrasound 9/9 (usually appropriate) as the first-line diagnostic test for right upper quadrant pain evaluation in this exact clinical scenario—a patient with mild RUQ pain following recent trauma. 1, 2 This recommendation is based on several critical factors:

• Ultrasound excels at detecting delayed traumatic complications that can present days to weeks after blunt abdominal trauma, including subcapsular hepatic hematomas, hepatic lacerations, bilomas, bile duct injuries, and hemobilia. 1, 3

• The patient's vital stability does not exclude significant injury. Delayed presentations of blunt abdominal trauma can be life-threatening, including evolving hepatic injuries and strangulated diaphragmatic herniae that may present with only mild symptoms initially. 1, 4

• Ultrasound provides rapid, cost-effective diagnosis without radiation exposure while simultaneously evaluating for both traumatic injuries and incidental gallbladder pathology that may have been precipitated by the trauma. 1, 2

Why Emergency Department Referral is Premature

Referring this vitally stable patient to the emergency department without any diagnostic workup is inappropriate because:

• The patient is hemodynamically stable with only mild pain, which does not meet criteria for immediate emergency referral without diagnostic evaluation. 5

• Outpatient ultrasound can be obtained rapidly and will guide whether emergency referral is actually necessary based on findings. 1

• Emergency departments will perform the same ultrasound as the initial diagnostic test, making direct referral without imaging an unnecessary step that delays diagnosis. 6

Why Blood Work Alone is Insufficient

While laboratory studies have a role, they cannot replace imaging in this scenario:

• Many traumatic abdominal injuries require imaging for diagnosis and cannot be detected by laboratory values alone, as clinical examination and labs have limited sensitivity for detecting hepatobiliary trauma. 1

• Laboratory studies should be obtained concurrently with ultrasound, including complete blood count and liver function tests to assess for anemia, leukocytosis, and hepatobiliary injury, but they complement rather than replace imaging. 1

• Normal hemoglobin does not exclude significant injury in the acute setting, as equilibration may take hours and subcapsular hematomas may not cause immediate hemorrhage. 3

Critical Clinical Algorithm

Step 1: Order right upper quadrant ultrasound immediately to evaluate for hepatic injury, biliary pathology, and free fluid suggesting hemorrhage. 1

Step 2: Obtain concurrent laboratory studies including complete blood count and liver function tests while awaiting ultrasound results. 1

Step 3: If ultrasound is negative or equivocal and clinical suspicion remains high for traumatic injury, proceed to CT abdomen/pelvis with IV contrast for comprehensive evaluation of solid organ injuries, bowel injuries, and vascular complications, as CT has superior sensitivity for detecting traumatic abdominal pathology. 1

Step 4: If ultrasound demonstrates biliary pathology requiring further characterization, proceed to MRCP, which provides 85-100% sensitivity and 90% specificity for biliary tree evaluation. 1, 7

Avoiding Critical Pitfalls

• Never dismiss mild symptoms in the setting of recent trauma. The case literature documents patients with strangulated diaphragmatic herniae presenting 18 months after trauma with only RUQ pain, requiring emergency laparotomy and bowel resection. 4

• Do not skip imaging and rely solely on clinical examination. Bedside ultrasound has proven effective in diagnosing subcapsular liver hematomas in patients presenting with RUQ pain after procedures, and the same principle applies to trauma patients. 3

• Do not proceed directly to CT without ultrasound unless the patient is hemodynamically unstable, as ultrasound is more appropriate for initial evaluation and avoids unnecessary radiation exposure. 2