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Published on: August 3, 2018
Laryngeal force sensor metrics are predictive of increased perioperative narcotic requirements
Allen L Feng1,2, Alex Ciaramella3, Matthew R Naunheim1,2
1Department of Otolaryngology, Harvard Medical School, Boston, Massachusetts, U.S.A.
Objectives/Hypothesis:
To determine the relationship between force metrics measured by the laryngeal force sensor (LFS) during suspension microlaryngoscopy (SML) and perioperative narcotic requirements.
Study Design:
Prospective observational study.
Methods:
Compressive tissue forces were recorded during SML using the LFS and correlated with postoperative narcotic requirements in the postanesthesia care unit (PACU) at an academic tertiary center. Patients were prospectively enrolled and had force metrics recorded throughout each procedure including maximum force, average force, suspension time, and total impulse. Narcotic administration in the intraoperative period and PACU were also recorded and converted into intravenous morphine equivalents (ME). Surgeons were blinded to the force recordings during surgery to prevent operator bias.
Results:
Eighty-two patients completed the study. Of these patients, the mean perioperative ME requirement was 16.96 mg (range, 0.15-79.82 mg). Univariate analysis demonstrated a positive correlation between perioperative narcotic requirements and total suspension time (P < .001) as well as total impulse (P = .007). A positive correlation was also seen with maximum force, although not significantly. On multiple linear regression, total suspension time was a significant predictive variable for perioperative narcotic use, with a marginal incremental increase of 0.273 mg of ME per minute of total suspension time (0.273 mg/min, 95% confidence interval: 0.040-0.507 mg/min, P = .022).
Conclusions:
Intraoperative force metrics including total suspension time are predictive of increased perioperative narcotic requirement after SML. Total impulse during SML may also correlate with increased perioperative narcotic requirements.
Level Of Evidence:
2 Laryngoscope, 129:2563-2567, 2019.
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