Comparison of Brain Temperature with Bladder and Rectal... : Neurosurgery (original) (raw)

Clinical Studies

Comparison of Brain Temperature with Bladder and Rectal Temperatures in Adults with Severe Head Injury

Henker, Richard A. RN, PhD; Brown, Sharon Danielle RN, MS; Marion, Donald W. MD

Department of Acute/Tertiary Care (RAH), School of Nursing, and Department of Neurosurgery (SDB, DWM), School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania

Received, April 17, 1997. Accepted, December 17, 1997.

Reprint requests: Richard Henker, R.N., Ph.D., 2939 Greenfield Road, Glenshaw, PA 15116.

Abstract

OBJECTIVE:

The purpose of this study was to compare brain temperature (Tbr) with conventional indicators of core body temperature (i.e., rectal temperature[Tre] and bladder temperature [Tbl]), in adults with severe head injury.

METHODS:

The relationships between Tbr and Tbl and between Tbr and Tre are described in terms of differences in temperature in eight patients with severe head injury.

INSTRUMENTATION:

Brain tissue temperature was measured every minute, with a thermocouple embedded 2 cm from the tip of a ventriculostomy catheter used to measure intracranial pressure. Tbl was measured with a thermistor embedded in a bladder catheter, and Tre was measured with a thermistor in a rectal probe.

RESULTS:

Tbr was usually greater than Tbl and Tre. The average difference between Tbr and Tbl for each patient ranged from 0.32 to 1.9°C, with standard deviations of the difference ranging from 0.30 to 0.80°C. The average difference between Tbr and Tre for each patient ranged from 0.1 to 2.0°C, with standard deviations of the difference ranging from 0.32 to 1.08°C. In the majority of patients, the differences (Tbr - Tbl and Tbr - Tre) were greater at temperatures outside of the normal temperature range (Tbr≤36°C and >38°C).

CONCLUSION:

Tbl and Tre often underrepresent Tbr after traumatic brain injury, particularly when the patient is hypo- or hyperthermic.