What is the most important thing to do when a patient develops fever on postoperative day 4 after a sigmoid resection?

Most Important Action: Assess the Wound

On postoperative day 4 after sigmoid resection, the most important action is to assess the wound (Option C), as surgical site infections are equally likely as other infections at this timepoint and require immediate visual inspection to detect potentially serious complications that demand urgent intervention. 1

Why Wound Assessment Takes Priority

Timing is Critical

• Fever on postoperative day 4 (96 hours) represents a critical transition point where surgical site infections become as likely as other infectious causes 1, 2
• Unlike early postoperative fever (first 48-72 hours), which is typically benign inflammatory response, day 4 fever warrants aggressive investigation for infection 1, 2
• Surgical site infections rarely occur in the first 48 hours, but by day 4 they must be actively excluded 1, 2

What to Look for During Wound Examination

The Infectious Diseases Society of America mandates inspecting for: 1

• Purulent drainage (any amount requires immediate intervention)
• Spreading erythema (measure extent from incision)
• Induration, warmth, tenderness, or swelling
• Any necrosis (requires emergency opening of suture line)

Immediate Action Required If:

• Erythema extends >5 cm from incision with induration 1
• Any necrosis is present 1
• Purulent drainage is identified 1

These findings mandate immediate opening of the suture line, empiric antibiotics (cephalosporin + metronidazole, levofloxacin + metronidazole, or carbapenem for sigmoid resection), and dressing changes. 1

Why Other Options Are Secondary

Blood Cultures (Option B)

• Should be obtained after wound assessment, not before 1
• Only indicated when temperature ≥38°C is accompanied by systemic signs beyond isolated fever (hemodynamic instability, altered mental status, signs of bacteremia/sepsis) 1, 2
• The American College of Critical Care Medicine mandates removing surgical dressings to inspect wounds before obtaining blood cultures 1

Chest X-ray (Option A)

• Not mandatory on day 4 if fever is the only indication 1, 2
• Only becomes indicated if respiratory symptoms develop 1, 2
• Has low diagnostic yield in asymptomatic patients (only 6% positive in one study) 3

Review Medications (Option D)

• Drug-induced fever typically develops with mean lag time of 21 days (median 8 days) after drug initiation 4
• Medication review becomes important when infectious workup is negative or fever persists beyond 48-72 hours despite appropriate therapy 4
• Should not delay wound assessment, which takes seconds to perform 1

Clinical Algorithm for Day 4 Postoperative Fever

Step 1: Immediate wound inspection (takes <1 minute) 1

• Remove dressings completely
• Inspect entire incision
• Document findings

Step 2: If wound shows infection signs 1

• Open suture line if erythema >5 cm with induration or any necrosis
• Obtain Gram stain and culture of purulent drainage
• Start empiric antibiotics immediately (cephalosporin + metronidazole for sigmoid resection)
• Implement dressing changes

Step 3: If wound appears normal 1, 2

• Obtain blood cultures if systemic signs present (not just fever alone)
• Consider chest X-ray only if respiratory symptoms
• Evaluate for urinary tract infection if catheter >72 hours or urinary symptoms
• Consider deep venous thrombosis/pulmonary embolism in high-risk patients

Common Pitfalls to Avoid

• Never assume fever is benign on day 4 - this is past the window of normal inflammatory response 1, 2
• Never order tests before examining the wound - physical examination has highest diagnostic yield and takes seconds 3, 5
• Never attribute fever to atelectasis without investigation - atelectasis should be a diagnosis of exclusion 2, 6
• Never start empiric antibiotics before obtaining cultures when possible - this compromises diagnostic accuracy 4

Red Flags Requiring Immediate Escalation

Any of the following mandate urgent surgical consultation: 1, 4

• Hemodynamic instability
• Altered mental status
• Respiratory compromise
• Signs of necrotizing infection (severe systemic toxicity, hypotension, organ dysfunction)
• Persistent fever beyond 48-72 hours despite appropriate therapy