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The influence of anesthesia on heart rate complexity during elective and urgent surgery in 128 patients. J Crit Care 2015 Feb;30(1):145-9

Date

09/23/2014

Pubmed ID

25239820

DOI

10.1016/j.jcrc.2014.08.008

Scopus ID

2-s2.0-84920562033 (requires institutional sign-in at Scopus site)   8 Citations

Abstract

BACKGROUND: As an emerging "new vital sign," heart rate complexity (by sample entropy [SampEn]) has been shown to be a useful trauma triage tool by predicting occult physiologic compromise and need for life-saving interventions. Sample entropy may be confounded by anesthesia possibly limiting its value intraoperatively. We investigated the effects of anesthesia on SampEn during elective and urgent surgical procedures. We hypothesized that SampEn is reduced by general anesthesia.

METHODS: With institutional review board-approved waiver of informed consent, 128 patients undergoing elective or urgent general surgery were prospectively enrolled. Real-time heart rate complexity was calculated using SampEn through electrocardiogram recordings of 200 consecutive beats in a continuous sliding-window fashion. We recorded SampEn starting 10 minutes before induction until 10 minutes after emergence from anesthesia. The time before induction of anesthesia was categorized as period 1, the time after induction and before emergence as period 2 (intraoperative), and the time after emergence as period 3. We analyzed SampEn changes as patients moved between the different periods and made 3 comparisons: from period 1 with period 2 (comparison A), from period 2 with period 3 (comparison B). We also compared period 1 with period 3 SampEn (comparison C).

RESULTS: The mean SampEn value for all patients before induction of anesthesia was 1.55 ± 0.58. In each 1 of the 3, comparisons there was a decline in SampEn. Comparison A had a mean decrease of 0.53 ± 0.55 (P < .0001), comparison B had a decrease of 0.13 ± 0.52 (P < .0051), and the mean SampEn difference for comparison C was 0.66 ± 0.53 (P < .0001). Certain pharmacologics had significant effect on SampEn as did need for urgent surgery and American Society of Anesthesiologists class.

CONCLUSION: Sample entropy decreases after induction of anesthesia and continues to decrease even immediately after emergence in patients without any immediately life-threatening conditions. This finding may complicate interpretation low complexity as a predictor of life-saving interventions in patients in the perioperative period.

Author List

Naraghi L, Peev MP, Esteve R, Chang Y, Berger DL, Thayer SP, Rattner DW, Lillemoe KD, Kaafarani H, Yeh DD, de Moya MA, Fagenholz PJ, Velmahos GS, King DR

Author

Marc Anthony De Moya MD Chief, Professor in the Surgery department at Medical College of Wisconsin




MESH terms used to index this publication - Major topics in bold

Adult
Aged
Anesthesia, General
Anesthetics
Elective Surgical Procedures
Electrocardiography
Emergencies
Entropy
Female
Heart Rate
Humans
Male
Middle Aged
Prospective Studies
Triage