Decreased respiratory depression during emergence from anesthesia with sevoflurane/N2O than with sevoflurane alone

Abstract

Decreased respiratory depression during emergence from anesthesia with sevoflurane/N20 than with sevoflurane alone Purpose: To investigate ventilation and gas elimination during the emergence from inhalational anesthesia with controlled normoventilation with either sevoflurane/N20 or sevoflurane alone. Methods: Twenty-four ASA I-II patients scheduled for abdominal hysterectomy were randomly allocated to receive either 1.3 MAC sevoflurane/N20 (n= 12) or equi-MAC sevoflurane (n= 12) in 30% oxygen (02). Expired minute ventilation volumes (VE), end-tidal (ET) concentrations of 02, carbon dioxide (CO2), sevoflurane and N20 as well as pulse oximetry saturation (SpO2) and CO 2 elimination rates (VCO2) were measured. The ET concentrations of sevoflurane and N20 were converted to total MAC values and gas elimination was expressed in terms of MAC reduction. Time to resumption of spontaneous breathing and extubation were recorded and arterial blood gas analysis was performed at the end of controlled normoventilation and at the beginning of spontaneous breathing. Results: Resumption of spontaneous breathing and extubation were 8 and 13 min less, respectively, in the sevoflurane/NzO than in the sevoflurane group. Spontaneous breathing was resumed in both groups when pH had decre .ased by 0.07-0.08 and PaCO 2 increased by 1.3-1.5 kPa. Depression of V E and VCO 2 were less, and MAC reduction more rap~d ~n the sevoflurane/N20 than ~n the sevoflurane group. Condu,sions: Respiratory recovery was faster after sevoflurane/N20 than sevoflurane anesthesia. Changes in pH and PaCO~ rather than absolute values were important for resumption of spontaneous breathing after controlled normoventdation. In both groups, the tracheas were extubated at about 0.2 MAC.Objectif: Observer la ventilation et 1'61imination des gaz pendant la r&up&ation de I'anesth6sie par inhalation avec une normoventilation contr61&, en utilisant un m~lange de s6voflurane/N20 ou seulement du s6voflurane. M6thode : Vingt-quatre patientes ASA I-II, dont I'hyst&ectomie abdominale ~tait pr~vue, ont 6t~ r~parties au hasard pour recevoir soit 1,3 CAM de s6voflurane/N20 (n = 12) ou la CAM 6quivalente de s6voflurane (n --12) dans 30 % d'oxyg~ne (02). On a pris les mesures suivantes : volumes expir& de ventilation-minute (VE), concentrations d'O 2 de fin d'expiration, gaz carbonique (CO2), s6voflurane et N20, saturation en oxyg~ne par oxym&rie puls& (SpO2) et vitesses d'61imination du CO 2 (VCO2). Les concentrations de s6voflurane et de N20 de fin d'expiration ont 6t6 transform&s en valeurs de CAM totales et 1'61imination des gaz a &6 exprim& en termes de r~duction de CAM. Le temps n&essaire au retour de la respiration spontan& et ~ I'extubation a ~t6 not6, I'analyse des gaz du sang art~del a ~t~ r6alis~e ~ la fin de la normoventilation contr61& et au d6but de la respiration spontan6e. R&-~ltats : Le retour de la respiration spontan6e et I'extubation ont demand~ 8 et 13 min de moins, respectivement, avec le s6voflurane/N20 qu'avec le s~voflurane seul. La reprise de la respirat...

Sevoflurane inside and outside the operating room

“…Initially, ventilation rate increases but does not compensate the decrease of tidal volume [11]. Respiratory recovery and extubation take around 13 min [70]. Sevoflurane has a direct bronchodilating effect.…”

European Society of Anaesthesiology Task Force on Nitrous Oxide: a narrative review of its role in clinical practice

“…27e30 The partial substitution of sevoflurane with an equal MAC multiple of N 2 O promotes spontaneous ventilation during maintenance 31 and restores spontaneous respiration faster at the end of the procedure. 32 Combining propofol with 40% N 2 O in O 2 for dental sedation not only reduces propofol requirements when compared with propofol alone, but also attenuates the hypotensive effects of propofol sedation. 33 Emergence N 2 O hastens emergence from anaesthesia for a number of reasons.…”

Sevoflurane: Approaching the Ideal Inhalational Anesthetic A Pharmacologic, Pharmacoeconomic, and Clinical Review

“…Respiratory recovery was measured after anesthesia with sevoflurane with or without nitrous oxide (68). Resumption of spontaneous breathing and extubation took 8 min with sevoflurane/nitrous oxide and 13 min with sevoflurane alone.…”