Effects of hypothermia on brainstem auditory evoked potentials in humans

✍ Scribed by Dr Omkar N. Markand; Byung I. Lee; Carroll Warren; Robert K. Stoelting; Robert D. King; John W. Brown; Yousuf Mahomed

• Publisher: John Wiley and Sons
• Year: 1987
• Tongue: English
• Weight: 567 KB
• Volume: 22
• Category: Article
• ISSN: 0364-5134
• DOI: 10.1002/ana.410220410

✦ Synopsis

Ten adult patients who underwent open heart surgery under induced hypothermia had brainstem auditory evoked potentials (BAEPs) recorded at 1 degree- to 2 degrees C-steps as body temperature was lowered from 36 degrees C to 20 degrees C to determine temperature-dependent changes. Hypothermia produced increased latencies of BAEP waves I, III, and V; the prolongation was more severe for the later components with the result that interpeak latencies I-III, III-V, and I-V were also prolonged. The temperature-latency relationship was nonlinear and best expressed by exponential curve. The latencies of waves I, III, V and the interpeak latency I-V increased roughly 7% for each 1 degree C drop; they doubled at a temperature around 26 degrees C. The amplitude of the BAEP components had a quasiparabolic relationship to temperature; the amplitude rose with hypothermia to 28 degrees or 27 degrees C, but decreased linearly with further cooling. All BAEP components were present at temperatures above 23 degrees C and absent below 20 degrees C. With rewarming, the changes reversed and BAEPs returned to initial prehypothermia status.