title: Monitoring nociception during general anesthesia with cardiorespiratory coherence.
abstract: A novel wavelet transform cardiorespiratory coherence (WTCRC) algorithm has been developed to measure the autonomic state. WTCRC may be used as a nociception index, ranging from 0 (no nociception, strong coherence) to 100 (strong nociception, low coherence). The aim of this study is to estimate the sensitivity of the algorithm to nociception (dental dam insertions) and antinociception (bolus doses of anesthetic drugs). WTCRC's sensitivity is compared to mean heart rate (HRmean) and mean non-invasive blood pressure (NIBPmean), which are commonly used clinical signs. Data were collected from 48 children receiving general anesthesia during dental surgery. The times of dental dam insertion and anesthetic bolus events were noted in real-time during surgeries. 42 dental dam insertion and 57 anesthetic bolus events were analyzed. The change in average WTCRC, HRmean, and NIBPmean was calculated between a baseline period before each event and a response period after. A Wilcoxon rank-sum test was used to compare changes. Dental dam insertion changed the WTCRC nociception index by an average of 14 (82 %) [95 % CI from 7.4 to 19], HRmean by 7.3 beats/min (8.1 %) [5.6-9.6], and NIBPmean by 8.3 mmHg (12 %) [4.9-13]. A bolus dose of anesthetics changed the WTCRC by -15 (-50 %) [-21 to -9.3], HRmean by -4.8 beats/min (4.6 %) [-6.6 to -2.9], and NIBPmean by -2.6 mmHg (3.4 %) [-4.7 to -0.50]. A nociception index based on cardiorespiratory coherence is more sensitive to nociception and antinociception than are HRmean or NIBPmean. The WTCRC algorithm shows promise for noninvasively monitoring nociception during general anesthesia.
authors.affiliation: Department of Electrical and Computer Engineering, University of British Columbia, Vancouver, BC, Canada, chris.brouse@gmail.com.
authors.forename: Chris J
authors.initials: CJ
authors.lastname: Brouse
authors.forename: Walter
authors.initials: W
authors.lastname: Karlen
authors.forename: Guy A
authors.initials: GA
authors.lastname: Dumont
authors.forename: Dorothy
authors.initials: D
authors.lastname: Myers
authors.forename: Erin
authors.initials: E
authors.lastname: Cooke
authors.forename: Jonathan
authors.initials: J
authors.lastname: Stinson
authors.forename: Joanne
authors.initials: J
authors.lastname: Lim
authors.forename: J Mark
authors.initials: JM
authors.lastname: Ansermino
mesh_terms: D000768:Anesthesia, General / Q000379:methods*; D018681:Anesthetics, General / Q000008:administration & dosage; D002648:Child; D002675:Child, Preschool; D003936:Diagnosis, Computer-Assisted / Q000379:methods; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D016343:Monitoring, Intraoperative / Q000379:methods*; D019647:Oral Surgical Procedures / Q000009:adverse effects / Q000379:methods*; D010147:Pain Measurement / Q000379:methods*; D010149:Postoperative Pain / Q000175:diagnosis* / Q000209:etiology; D015742:Propofol / Q000008:administration & dosage; D015203:Reproducibility of Results; D056152:Respiratory Rate; D012680:Sensitivity and Specificity; D058067:Wavelet Analysis
chemical_list: D018681:Anesthetics, General; D015742:Propofol