Inhalational Agent Dosing Behaviors of Anesthesia Practitioners Cause Variability in End-Tidal Concentrations at the End of Surgery and Prolonged Times to Tracheal Extubation

Franklin Dexter; Richard H Epstein; Vivian Ip; Anil A Marian

doi:10.7759/cureus.65527

Back

Inhalational Agent Dosing Behaviors of Anesthesia Practitioners Cause Variability in End-Tidal Concentrations at the End of Surgery and Prolonged Times to Tracheal Extubation

Journal article

Open access

Peer reviewed

Inhalational Agent Dosing Behaviors of Anesthesia Practitioners Cause Variability in End-Tidal Concentrations at the End of Surgery and Prolonged Times to Tracheal Extubation

Franklin Dexter, Richard H Epstein, Vivian Ip and Anil A Marian

Curēus (Palo Alto, CA), Vol.16(7), e65527

07/27/2024

DOI: 10.7759/cureus.65527

PMCID: PMC11346799

PMID: 39188447

Files and links (1)

url

https://doi.org/10.7759/cureus.65527View

Published (Version of record) Open Access

Abstract

Introduction: Prolonged times to tracheal extubation are intervals from the end of surgery to extubation ≥15 minutes. We examined why there are associations with the end-tidal inhalational agent concentration as a proportion of the age‑adjusted minimum alveolar concentration (MAC fraction) at the end of surgery. Methods: The retrospective cohort study used 11.7 years of data from one hospital. All p‑values were adjusted for multiple comparisons. Results: There was a greater odds of prolonged time to extubation if the anesthesia practitioner was a trainee (odds ratio 1.68) or had finished fewer than five cases with the surgeon during the preceding three years (odds ratio 1.12) (both P<0.0001). There was a greater risk of prolonged time to extubation if the MAC fraction was >0.4 at the end of surgery (odds ratio 2.66, P<0.0001). Anesthesia practitioners who were trainees and all practitioners who had finished fewer than five cases with the surgeon had greater mean MAC fractions at the end of surgery and had greater relative risks of the MAC fraction >0.4 at the end of surgery (all P<0.0001). The source for greater MAC fractions at the end of surgery was not greater MAC fractions throughout the anesthetic because the means during the case did not differ among groups. Rather, there was substantial variability of MAC fractions at the end of surgery among cases of the same anesthesia practitioner, with the mean (standard deviation) among practitioners of each practitioner's standard deviation being 0.35 (0.05) and the coefficient of variation being 71% (13%). Conclusion: More prolonged extubations were associated with greater MAC fractions at the end of surgery. The cause of the large MAC fractions was the substantial variability of MAC fractions among cases of each practitioner at the end of surgery. That variability matches what was expected from earlier studies, both from variability among practitioners in their goals for the MAC fraction given at the start of surgical closure and from inadequate dynamic forecasting of the timing of when surgery would end. Future studies should examine how best to reduce prolonged extubations by using anesthesia machines' display of MAC fraction and feedback control of end-tidal agent concentration.

Details

Title: Subtitle: Inhalational Agent Dosing Behaviors of Anesthesia Practitioners Cause Variability in End-Tidal Concentrations at the End of Surgery and Prolonged Times to Tracheal Extubation
Creators: Franklin Dexter - University of Iowa, Anesthesia
Richard H Epstein - University of Miami Health System
Vivian Ip - University of Calgary
Anil A Marian - University of Iowa
Resource Type: Journal article
Publication Details: Curēus (Palo Alto, CA), Vol.16(7), e65527
DOI: 10.7759/cureus.65527
PMID: 39188447
PMCID: PMC11346799
NLM abbreviation: Cureus
ISSN: 2168-8184
eISSN: 2168-8184
Language: English
Date published: 07/27/2024
Academic Unit: Anesthesia
Record Identifier: 9984691553602771

Metrics

6 Record Views

3 Times Cited - Web of Science