What is the appropriate workup for a patient presenting with shortness of breath (SOB), abdominal (ABD) pain with bloody stool, and chest pain?

Comprehensive Workup for a Patient with SOB, Abdominal Pain with Bloody Stool, and Chest Pain

For a patient presenting with the triad of shortness of breath, abdominal pain with bloody stool, and chest pain, immediate emergency department evaluation is required as this constellation of symptoms suggests potentially life-threatening conditions requiring urgent assessment and management.

Initial Assessment and Stabilization

First Priority: Cardiopulmonary Assessment

• Obtain vital signs immediately (heart rate, blood pressure, respiratory rate, oxygen saturation, temperature)
• Place on continuous cardiac monitoring
• Administer supplemental oxygen if hypoxic (O2 saturation <94%)
• Obtain immediate 12-lead ECG within 10 minutes of arrival 1
• Establish IV access for potential fluid resuscitation and medication administration

Second Priority: Focused History

• Onset, duration, and character of symptoms
• Chest pain characteristics: location, radiation, quality, severity, aggravating/alleviating factors
• Abdominal pain characteristics: location, radiation, association with meals
• Bloody stool: quantity, frequency, color (bright red vs. melena)
• Shortness of breath: onset, exertional vs. at rest
• Associated symptoms: nausea, vomiting, diaphoresis, fever, syncope
• Past medical history, especially cardiac, gastrointestinal, or pulmonary conditions
• Medication history, particularly NSAIDs, anticoagulants, vasopressors 2

Third Priority: Focused Physical Examination

• Cardiovascular: heart sounds, murmurs, jugular venous distension
• Pulmonary: breath sounds, work of breathing, accessory muscle use
• Abdominal: tenderness, guarding, rigidity, rebound, distension
• Rectal examination: presence of blood, melena
• Skin: pallor, diaphoresis, cyanosis

Diagnostic Workup

Immediate Laboratory Tests

• Complete blood count with differential (assess for anemia, leukocytosis)
• Basic metabolic panel (electrolytes, renal function)
• Cardiac biomarkers (high-sensitivity troponin preferred) 1
• Coagulation studies (PT/INR, PTT)
• Lactate level (to assess for tissue hypoperfusion)
• Arterial or venous blood gas (if respiratory distress)
• Blood cultures (if febrile or suspected infection)
• Stool studies for blood, fecal leukocytes, C. difficile, bacterial pathogens 1, 3

Immediate Imaging

• Chest radiograph (to assess for pulmonary pathology, free air under diaphragm)
• Abdominal radiograph (to assess for obstruction, free air)
• Consider bedside ultrasound to evaluate for abdominal aortic aneurysm, free fluid

Secondary Imaging Based on Initial Results

• CT angiography of chest if pulmonary embolism or aortic dissection suspected 1
• CT abdomen/pelvis with IV contrast if mesenteric ischemia, bowel obstruction, or other abdominal pathology suspected 1
• Coronary CT angiography or stress testing if ACS is suspected but initial ECG and troponins are negative 1

Specialized Testing Based on Clinical Suspicion

• Emergent colonoscopy if lower GI bleeding is significant
• Esophagogastroduodenoscopy if upper GI bleeding is suspected
• Echocardiography if cardiac etiology is suspected

Differential Diagnosis to Consider

Cardiac Causes

• Acute coronary syndrome/myocardial infarction
• Myocarditis (especially with concurrent GI symptoms) 3
• Pericarditis
• Aortic dissection

Pulmonary Causes

• Pulmonary embolism
• Pneumonia with sepsis
• Pneumothorax

Gastrointestinal Causes

• Mesenteric ischemia/colonic ischemia 2
• Inflammatory bowel disease exacerbation
• Infectious colitis (including Campylobacter, which can cause both GI symptoms and myocarditis) 3
• Bowel obstruction 1, 4
• Diverticulitis with microperforation

Combined Pathologies

• Sepsis with multiorgan involvement
• Vasculitis affecting multiple organ systems

Management Approach

The management should be guided by the findings from the initial assessment:

1. If ECG shows ST-elevation or high-risk features: Activate cardiac catheterization lab for potential primary PCI 1

2. If CT angiography shows pulmonary embolism: Initiate anticoagulation if no contraindications

3. If abdominal imaging suggests mesenteric ischemia or bowel obstruction: Urgent surgical consultation 1

4. If infectious colitis is suspected: Initiate appropriate antimicrobial therapy based on likely pathogens 3

5. If significant GI bleeding: Volume resuscitation, correction of coagulopathy, and consideration of endoscopic intervention

Common Pitfalls to Avoid

• Attributing all symptoms to a single diagnosis: This symptom triad often represents multiple pathologies or a systemic process
• Focusing only on cardiac causes: While chest pain warrants cardiac evaluation, the concurrent GI symptoms require equal attention
• Delaying imaging studies: Particularly in suspected mesenteric ischemia where early diagnosis is crucial for bowel preservation
• Overlooking infectious causes: Certain pathogens like Campylobacter can cause both GI symptoms and cardiac manifestations 3
• Inadequate fluid resuscitation: Patients with GI bleeding may be significantly volume depleted despite normal initial vital signs

Special Considerations

• In elderly patients, presentation may be atypical with less pronounced pain but more significant physiological derangements 1
• Consider sickle cell disease in appropriate populations, as acute chest syndrome can present with this symptom constellation 1
• Medication-induced colonic ischemia should be considered, particularly with NSAIDs, vasopressors, and certain hormonal therapies 2

This patient requires admission for comprehensive evaluation and management, with consideration of ICU-level care depending on hemodynamic stability and severity of findings.