From the Guidelines
The workup for postoperative fever on day 3 after surgery should focus on identifying common causes like atelectasis, urinary tract infections, and early surgical site infections, with a thorough history and physical examination, and selective use of diagnostic tests such as chest imaging and wound cultures, as recommended by the most recent guidelines 1.
Key Components of the Workup
- A thorough history and physical examination, paying particular attention to the surgical site, respiratory status, and urinary symptoms
- Order a complete blood count with differential, urinalysis, urine culture, and blood cultures if the patient appears septic
- Chest imaging (X-ray or CT) should be obtained to evaluate for atelectasis or pneumonia, as recommended by the Society of Critical Care Medicine and the Infectious Diseases Society of America 1
- Examine the surgical site carefully for signs of infection such as erythema, warmth, tenderness, or purulent drainage; if present, obtain wound cultures and consider imaging to evaluate for deeper infections or collections
Diagnostic Considerations
- The timing of postoperative fever often provides clues to the etiology, with day 3 fevers commonly associated with atelectasis, UTIs, or early wound infections, while later fevers may suggest deep space infections or venous thromboembolism
- Additional studies may include C-reactive protein and procalcitonin to assess the inflammatory response
- Empiric antibiotics should be initiated if there are signs of infection, with the choice guided by the suspected source - typically a third-generation cephalosporin or fluoroquinolone for UTI, or broader coverage with piperacillin-tazobactam or meropenem for suspected intra-abdominal infections, adjusting based on culture results 1
Surgical Site Infections
- SSIs are divided into the categories of superficial incisional SSI, deep incisional SSI, and organ/space SSI
- The most important therapy for an SSI is to open the incision, evacuate the infected material, and continue dressing changes until the wound heals by secondary intention 1
- Patients with temperature >38.5°C or heart rate >110 beats/minute or erythema extending beyond the wound margins for >5 cm may require a short course (eg, 24–48 hours) of antibiotics, as well as opening of the suture line.
From the Research
Postoperative Fever Workup
The workup for postoperative fever 3 days after surgery involves a focused approach to identify the underlying cause of the fever. According to 2, fever that develops after the first 2 days following surgery is more likely to have an infectious cause, but noninfectious causes must also be considered.
Key Considerations
- A helpful mnemonic is the "four Ws":
- wind (pulmonary causes: pneumonia, aspiration, and pulmonary embolism)
- water (urinary tract infection)
- wound (surgical site infection)
- "what did we do?" (iatrogenic causes: drug fever, blood product reaction, infections related to intravenous lines) 2
- A brief bedside evaluation has the highest yield for determining the fever etiology, and extensive evaluations with cultures and chest imaging have little to no benefit in patients admitted for elective surgery 3
- New or continuing fever more than three days after surgery should raise a strong suspicion of persistent illness or a new complication 4
Diagnostic Approach
- Clinicians should differentiate between a normal physiologic response to surgery and one that may be pathologic, and further separate pathologic causes into infectious and noninfectious causes 5
- A systematic approach to febrile postoperative patients can help clinicians make better use of resources, limit costly workups, and improve patient outcomes 5
- Subsequent testing should be based on the clinical findings, and perhaps more money is wasted in the evaluation of early postoperative fever than on any other aspect of postoperative care 4