Does sealing endotracheal tube cuff pressure diminish the frequency of postoperative laryngotracheal complaints after nitrous oxide anesthesia?
OBJECTIVE
To study endotracheal tube (ETT) cuff pressures during nitrous oxide (N2O) anesthesia when the cuffs are inflated with air to achieve sealing pressure, and to evaluate the frequency of postoperative laryngotracheal complaints.


METHODS
Prospective, randomized, blind study.


METHODS
Metropolitan teaching hospital.


METHODS
50 ASA physical status I and II patients scheduled for elective abdominal surgery.


METHODS
Patients received standard general anesthesia with 66% N2O in oxygen. In 25 patients, the ETT cuff was inflated with air to achieve a sealing pressure (Pseal group). In 25 patients, the ETT cuff was inflated with air to achieve a pressure of 25 cm H2O (P25 group).


RESULTS
ETT intracuff pressures were recorded before (control) and at 30, 60, 90, 120, and 150 minutes during N2O administration. We investigated the frequency and intensity of sore throat, hoarseness, and dysphagia in patients in the Post-Anesthesia Care Unit (PACU) and 24 hours following tracheal extubation. The cuff pressures in the Pseal group were significantly lower than in the P25 group at all time points studied (p < 0.001), with a significant increase with time in both groups (p < 0.001). The cuff pressures exceeded the critical pressure of 30 cm H2O only after 90 minutes in the Pseal group and already by 30 minutes in the P25 group. The frequency and intensity of sore throat, hoarseness, and dysphagia were similar in both groups in the PACU and 24 hours after tracheal extubation (p > 0.05).


CONCLUSIONS
Minimum ETT sealing cuff pressure during N2O anesthesia did not prevent, but instead attenuated, the increase in cuff pressure and did not decrease postoperative laryngotracheal complaints.
Braz
José Reinaldo Cerqueira
JR
Department of Anesthesiology of the School of Medicine, UNESP, Botucatu, São Paulo, Brazil. jbraz@fmb.unesp.br
Volney
Alexandre
A
Navarro
Laís Helena Camacho
LH
Braz
Leandro Gobbo
LG
Nakamura
Giane
G
D000328:Adult; D000368:Aged; D000769:Anesthesia, Inhalation; D002675:Child, Preschool; D003680:Deglutition Disorders / Q000517:prevention & control*; D005260:Female; D006685:Hoarseness / Q000517:prevention & control*; D006801:Humans; D007442:Intubation, Intratracheal / Q000009:adverse effects / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009609:Nitrous Oxide / Q000494:pharmacology*; D010612:Pharyngitis / Q000517:prevention & control*; D011183:Postoperative Complications / Q000453:epidemiology / Q000517:prevention & control*; D011312:Pressure; D011446:Prospective Studies
D009609:Nitrous Oxide