Newly updated guidelines from IDSA and the American College of Critical Care Medicine are intended to help ICU physicians evaluate a new fever in their patients and determine whether infection is present so that additional testing can be avoided and therapeutic decisions can be made. The guidelines also offer a helpful background check for infectious diseases physicians who do consults in the ICU.

In some ICUs a new fever in a critically ill patient can trigger automatic orders for many time-consuming, costly, disruptive tests. The patient may experience discomfort, be exposed to unneeded radiation, have to be transported out of the controlled environment of the ICU, or experience considerable blood loss.

Because fever can have many infectious and noninfectious etiologies, a new fever instead should trigger a careful clinical assessment. “It’s important to make sure the measurement of temperature is an accurate reflection of the patient’s physiology,” said lead author Naomi P. O'Grady, MD, senior staff physician in the critical care medicine department of the National Institutes of Health. Any unexplained temperature elevation merits a clinical assessment that includes a review of the patient’s history and a focused physical examination before any lab tests or imaging procedures are ordered.

The new guidelines include a discussion of novel technologies to measure temperature, with the most accurate being pulmonary artery thermistor, urinary bladder catheter thermistor, esophageal probe, and rectal probe. Technologies to avoid include temporal artery thermometer, axillary thermometer and chemical dot.

A section on blood cultures reports that new data suggest that the cumulative yield of pathogens is optimized when three to four blood cultures are drawn within the first 24 hours of suspected bacteremia or fungemia.

The guidelines include specific recommendations for evaluation of:

• pulmonary infections and ICU-acquired pneumonia, including an evaluation of new technologies
• gastrointestinal tracts of patients who are at risk for Clostridium difficile, including a discussion of common antigen testing and follow up
• urinary tracts for infections related to urinary catheters including bacteriuria and candiduria
• sinusitis
• fever within 72 hours of surgery
• surgical site infections
• central nervous system infections

The guidelines also make recommendations about other considerations such as the use of biomarkers to determine the cause of fever and how to recognize noninfectious causes of fever, such as new medications.

Finally, the guidelines conclude with an expanded discussion of empiric therapy for unstable or high-risk patients while the diagnostic evaluation is ongoing.

The “Guidelines for Evaluation of New Fever in Critically Ill Adult Patients: 2008 Update from the American College of Critical Care Medicine and the Infectious Diseases Society of America,” were published in Critical Care Medicine. (O’Grady et al., Crit Care Med. 2008;36:1330-49.)

< Previous Article | Next Article >