Postoperative fever refers to an elevated body temperature (≥ 38.5 °C) occurring after a recent surgical procedure. Diagnosing the cause of postoperative fever can sometimes be challenging; while fever in this context may be benign, self-limited, or unrelated to the surgical procedure, it can also be indicative of a surgical complication, such as infection.
Causes
The most common causes of postoperative fever are often summarized for medical students by a
mnemonic
A mnemonic ( ) device, or memory device, is any learning technique that aids information retention or retrieval (remembering) in the human memory for better understanding.
Mnemonics make use of elaborative encoding, retrieval cues, and imag ...
beginning with the letter W. The classic list consists of five W's – Wind, Water, Wound, Walking, and Wonder Drugs,
but two other causes should also be considered – Wing/Waterway and (W)abscess. There is a characteristic timeframe after surgery when many of these complications tend to develop (postoperative days or POD).
Other important causes of early post-operative fever that are omitted from this list include
malignant hyperthermia
Malignant hyperthermia (MH) is a type of severe reaction that occurs in response to particular medications used during general anesthesia, among those who are susceptible. Symptoms include muscle rigidity, fever, and a fast heart rate. Complica ...
, a potentially life-threatening but treatable response to inhalational anesthetic and paralytic agents.
Early postoperative fever (i.e., within the first 48 hours post-operatively) has often been ascribed to atelectasis, or splinting, but it is most likely part of a natural and non-infectious inflammatory response (with sympathetic nervous system involvement) to the tissue injury sustained during surgery; it generally requires no medical intervention except antipyretics and extra fluid intake.
Workup
The diagnostic workup of post-operative fever is guided by the potential etiologies on the differential diagnosis. The patient's surgical and post-operative course should be reviewed in detail, noting whether the patient has been regularly using an incentive spirometer or not, whether a Foley catheter was/is in place, what medications s/he has received, etc. The patient should be asked if s/he is having any pain (and where?) or other symptoms such as coughing or dysuria, which may help to localize the source of the fever. A thorough physical exam should be conducted, auscultating the lungs, noting erythema or drainage from the surgical incision(s), evaluating IV sites, noting lower extremity edema, etc.
Laboratory testing and imaging is generally deferred for evaluation of fever that occurs within the first 48 hours post-operatively, unless prompted by specific findings in the history and physical exam. Beyond 48 hours, testing routinely includes urine and blood cultures as well as a chest X-ray.
Popular culture
In the
pilot episode of the medical drama ''Grey's Anatomy'', Meredith Grey refers to this mnemonic: "Wind, water, wound, walking, wonder drugs. The 5 Ws. Most of the time it’s wind; splinting or pneumonia. Pneumonia is easy to assume. Especially if you're too busy to do the tests."
[http://leethomson.myzen.co.uk/Grey's_Anatomy/Grey's_Anatomy_1x01_-_A_Hard_Days_Night.pdf ]
See also
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Patient safety
Patient safety is a discipline that emphasizes safety in health care through the prevention, reduction, reporting and analysis of error and other types of unnecessary harm that often lead to adverse patient events. The frequency and magnitude of ...
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Perioperative mortality
Perioperative mortality has been defined as any death, regardless of cause, occurring within 30 days after surgery in or out of the hospital. Globally, 4.2 million people are estimated to die within 30 days of surgery each year. An important consi ...
References
{{DEFAULTSORT:Postoperative Fever
Surgery
Fever
Medical mnemonics