Postoperative fever evaluation

Postoperative fever evaluation

Postoperative fever evaluation

On this page

Post-op Fever Causes - The 5 W's

A systematic approach to diagnosing postoperative fever based on the timing of its onset.

5 Ws of Postoperative Fever

📌 MnemonicTimeframe (Post-Op)CauseKey Findings
Wind24-48 hrsAtelectasisLow-grade fever, tachypnea, decreased breath sounds.
Water>48-72 hrsUrinary Tract Infection (UTI)Dysuria, frequency, urgency. Often related to Foley catheters.
Wound>72 hrs (Day 5-7)Surgical Site Infection (SSI)Localized pain, erythema, warmth, purulent drainage.
Walking>72 hrs (Day 7-10)DVT / Pulmonary EmbolismDVT: Unilateral leg swelling, pain. PE: Pleuritic chest pain, SOB.
Wonder DrugsVariable (>1 week)Drug fever, blood productsFever of unknown origin, often a diagnosis of exclusion. May see rash.

Diagnostic Workup - From Fever to Finding

  • Initial Steps: Thorough physical exam focusing on surgical site, lungs, abdomen, calves, and all access lines (IVs, central lines, Foley).
  • Core Labs & Imaging:
    • CBC with differential (for leukocytosis).
    • Blood cultures (x2, from separate sites).
    • Urinalysis and urine culture.
    • Chest X-ray, especially with pulmonary signs.

⭐ Always obtain at least two sets of blood cultures from different venipuncture sites before starting empiric antibiotics to maximize diagnostic yield.

Management Principles - Dousing the Flames

  • General Measures:
    • Administer antipyretics (acetaminophen) for symptomatic control.
    • Ensure euvolemia and correct electrolyte abnormalities.
    • Remove potential sources of infection (e.g., central lines, Foley catheters) if clinically indicated.
  • Targeted Treatment (by cause):
    • Wind (Atelectasis/Pneumonia): Aggressive pulmonary toilet, incentive spirometry. For pneumonia, start empiric antibiotics (e.g., vancomycin + piperacillin-tazobactam).
    • Water (UTI): Replace catheter if still needed; start antibiotics based on local resistance patterns (e.g., ceftriaxone).
    • Wound (SSI): Open wound for drainage, perform dressing changes. Add antibiotics for significant cellulitis or systemic signs.
    • Walking (VTE): Initiate therapeutic anticoagulation (e.g., heparin or LMWH).
    • Wonder Drugs: Discontinue the offending agent.

⭐ In a patient with a surgical abscess, source control (incision and drainage) is the most critical step and should not be delayed for antibiotic therapy alone.

Postoperative Fever Etiologies

High‑Yield Points - ⚡ Biggest Takeaways

  • The "5 Ws" mnemonic is crucial for timing fever: Wind, Water, Walking, Wound, Wonder Drugs.
  • Atelectasis (Wind) is the most frequent cause in the first 48 hours.
  • UTIs (Water) are common after day 3, especially with Foley catheters.
  • DVT/PE (Walking) is a risk around days 5-7; suspect with leg swelling or pleuritic chest pain.
  • Surgical site infections (Wound) typically manifest after day 7.
  • Drug fever is a diagnosis of exclusion; an abscess is a late cause requiring a CT scan.

Practice Questions: Postoperative fever evaluation

Test your understanding with these related questions

A 56-year-old previously healthy woman with no other past medical history is post-operative day one from an open reduction and internal fixation of a fractured right radius and ulna after a motor vehicle accident. What is one of the primary ways of preventing postoperative pneumonia in this patient?

1 of 5

Flashcards: Postoperative fever evaluation

1/10

PSA can be used as a surveillance marker for recurrent disease after _____

TAP TO REVEAL ANSWER

PSA can be used as a surveillance marker for recurrent disease after _____

prostatectomy

browseSpaceflip

Enjoying this lesson?

Get full access to all lessons, practice questions, and more.

Start Your Free Trial