A 62-year-old man is evaluated on postoperative day 2 following a four-vessel coronary artery bypass grafting (CABG) procedure. His temperature is 38.3°C (101.0°F), blood pressure is 128/82 mmHg, pulse is 88/min, and respirations are 16/min. He reports mild chest wall pain at the incision site but denies shortness of breath, cough, dysuria, or leg swelling. Physical examination reveals decreased breath sounds at the lung bases bilaterally without crackles or wheezing. The sternal surgical wound is clean, dry, and intact with no erythema, induration, or discharge. His indwelling urinary catheter was removed on postoperative day 1. Which of the following is the most likely cause of this patient's fever?
- AtelectasisAnswer
- BSurgical site infection
- CCatheter-associated urinary tract infection
- DDeep vein thrombosis
- EDrug-induced fever
Answer
Atelectasis
The correct answer is atelectasis. Fever in the postoperative period is common and its timing is a strong predictor of the underlying cause, frequently remembered by the mnemonic '5 Ws': Wind (atelectasis, pneumonia; days 1-2), Water (urinary tract infection; days 3-5), Walking (deep vein thrombosis; days 5-7), Wound (surgical site infection; days 5-7), and Wonder drugs (drug fever; anytime but typically later). This patient is on postoperative day 2 following a CABG, making 'Wind' (atelectasis) the most statistically probable cause. This is further supported by the physical exam finding of decreased breath sounds at the lung bases. Atelectasis is particularly common after cardiothoracic surgeries due to sternal pain limiting deep inspiration and lung expansion.
Step-by-Step Solution
Key Concept
The most common cause of fever on postoperative days 1 to 2 is atelectasis ('Wind'), especially following surgeries that limit deep inspiration like CABG.