Impact of deep hypothermic circulatory arrest on the BIS index

Ziegeler, Stephan; Buchinger, Heiko; Wilhelm, Wolfram; Larsen, Reinhard; Kreuer, Sascha

doi:10.1016/j.jclinane.2009.09.007

« Previous Next »Journal of Clinical Anesthesia
Volume 22, Issue 5 , Pages 340-345, August 2010

Impact of deep hypothermic circulatory arrest on the BIS index☆☆☆★

Stephan Ziegeler, MD (Staff Anesthesiologist)
- Department of Anesthesiology, Intensive Care Medicine and Pain Therapy, University of Saarland, 66421 Homburg/Saar, Germany
- Corresponding author.
Heiko Buchinger, MD (Staff Anesthesiologist)
- Department of Anesthesiology, Intensive Care Medicine and Pain Therapy, University of Saarland, 66421 Homburg/Saar, Germany
Wolfram Wilhelm, MD (Director)
- Department of Anesthesiology and Intensive Care Medicine, Klinikum Luenen-St.-Marien-Hospital, 44534 Luenen, Germany
Reinhard Larsen, MD (Director)
- Department of Anesthesiology, Intensive Care Medicine and Pain Therapy, University of Saarland, 66421 Homburg/Saar, Germany
Sascha Kreuer, MD (Staff Anesthesiologist)
- Department of Anesthesiology, Intensive Care Medicine and Pain Therapy, University of Saarland, 66421 Homburg/Saar, Germany

Received 7 January 2008; received in revised form 4 September 2009; accepted 26 September 2009.

Abstract

Study Objective

To investigate the influence of duration of deep hypothermic circulatory arrest (DHCA) on recovery of the bispectral index (BIS).

Design

Prospective cohort study.

Setting

Operating room of university teaching hospital.

Patients

30 adult, ASA physical status III and IV patients scheduled for cardiac surgery with extracorporeal circulation (ECC) and DHCA.

Interventions

There were no study-specific interventions undertaken with the study patients.

Measurements

After induction of anesthesia, propofol and sufentanil were used for maintenance. Duration until BIS values reached indices of 10, 20, and 30 after DHCA was measured. ΔBIS was defined as the difference between BIS before the start of ECC and after DHCA at the same nasopharyngeal body temperature. Data are means ± SD (ranges).

Main Results

Duration of DHCA was 24 ± 15 min (8-71 min). The deepest nasopharyngeal temperature was 20.1 ± 2.7°C at the end of DHCA. BIS reduction was 1.8/°C. At the end of DHCA, BIS was 2 ± 6 and at the end of ECC, BIS was 33 ± 11. Duration until BIS reached a value of 10 (BIS10) was 23 ± 21 min (0-83 min); until BIS reached 20 (BIS20): 36 ± 36 min (0-140 min); and until BIS reached 30 (BIS30): 43 ± 29 min (1-130 min). Regression analysis between duration of DHCA and BIS10 was R = 0.76; BIS20: R = 0.67; and BIS30: R = 0.54.

Conclusion

Deep hypothermia influences BIS linearly. In addition, there appears to be a reasonable correlation between recovery of BIS values and duration of DHCA.

Keywords: Bispectral index, Deep hypothermic circulatory arrest, Extracorporeal circulation, Hypothermia