Perelman School of Medicine at the University of Pennsylvania
Center for Resuscitation Science

Temperature Monitoring

Q: I heard recently that a rectal temperature is contraindicated in a pt post MI. Can you explain to me why that is?

A: The general concern about rectal temperatures post-MI is that it might stimulate the vagus nerve and cause bradyarrhythmias. There aren't a lot of data to support this. Some institutions have successfully used rectal temp probes in post-arrest patients (without reported increases in bradyarrhythmias), though we don't feel this temp modality is as accurate as esophageal or bladder.

- David Gaieski, MD

October 06, 2010

Q: Can you tell me your experience with temperature monitoring - rectal probe, bladder probe etc.?

A: We use the temperature probe foley at Penn. If the patient is not producing enough urine (4cc/hr) we will put in an espophgeal probe. We try to stay away from rectal probes as there is a temperature lag that could be dangerous when initiating cooling. There was a Case Study published in 2009 that showed a significant delay between esophageal temperature (core temp) versus rectal probe. The patient was given saline boluses and the esophageal probe showed a temperature of 33.5 at 19 minutes while the rectal probe had the patient temperature at 35.5 at 19 min. The concern is that you could over-cool a patient and get into a dangerous range (30 degree C or lower) where ventricular rhythms could occur. There is also a lag with bladder temperature as well, but it is more evident with the rectal probe.

- Marion Leary BSN, RN