Dose optimale de rémifentanil pour l’insertion d’un masque laryngé lors de la co-administration d’une dose standard unique de propofol

Abstract

Purpose This dose-response study aimed to determine the optimal dose of remifentanil combined with propofol 2.5 mgÁkg -1 iv in order to achieve excellent conditions for laryngeal mask airway (LMA TM ) insertion in 95% of adult female patients. Methods Sixty-eight adult premedicated female patients, American Society of Anesthesiologists (ASA) physical status I and II requiring anesthesia for ambulatory surgery, were randomly allocated to one of four remifentanil dose groups (0.25, 0.5, 1, or 2 lgÁkg -1 ). Induction of anesthesia was achieved with one of the four blinded doses of remifentanil infused over 60 sec and simultaneously co-administered with propofol 2.5 mgÁkg -1 iv infused over 45 sec. Insertion of the LMA was attempted 150 sec after the beginning of the induction sequence. Insertion conditions were assessed using a six-category score according to resistance to mouth opening and insertion, swallowing, coughing and gagging, movement, and laryngospasm. A probit analysis was performed to calculate the effective dose for insertion of the LMA in 95% of patients (efficient dose [ED] 95 ). The changes in heart rate (HR) and mean arterial blood pressure (MAP) in response to LMA insertion were recorded and compared as secondary outcome variables. Results The ED 95 of remifentanil was 1.32 (95% confidence interval [CI] 0.99-2.46) lgÁkg -1 . Changes in heart rate and mean arterial pressure were modest and similar over time across groups, with maximum decreases in heart rate and mean arterial pressure \ 30% each during induction of anesthesia. Conclusions The required dose of remifentanil is 1.32 (95% CI 0.99-2.46) lgÁkg -1 to achieve excellent LMA insertion conditions in 95% of patients when co-administered with propofol 2.5 mgÁkg -1 in healthy premedicated female patients undergoing elective ambulatory surgery. RésuméObjectif L'objectif de cette e´tude de dose-re´ponse e´tait de de´terminer la dose optimale de re´mifentanil lors de l'administration conjointe de propofol 2,5 mgÁkg -1 iv afin d'obtenir des conditions excellentes pour l'insertion d'un masque larynge´(LMAÒ) chez 95 % de patientes adultes. Méthode Soixante-huit patientes adultes ASA I et II pre´me´dique´es et ne´cessitant une anesthe´sie pour une chirurgie ambulatoire ont e´te´randomise´es en quatre groupes selon la dose de re´mifentanil (0,25, 0,5, 1 ou 2 lgÁkg -1 ). L'induction de l'anesthe´sie a e´te´re´alise´e avec l'une des quatre doses de re´mifentanil en aveugle perfuse´e sur 60 secondes, administre´e simultane´ment a`du propofol 2,5 mgÁkg -1 iv perfuse´sur 45 secondes. L'insertion du Support was provided solely by institutional sources.

Target controlled remifentanil infusion for smooth laryngeal mask airway removal during emergence from desflurane–remifentanil anesthesia

“…Adequate depth of anesthesia with proper mouth opening must be provided for the successful placement of the LMA without any complication. Therefore, propofol has been successfully combined with different opioids, for example remifentanil, alfentanyl, and fentanyl, as reported in the literature [9,10]. Therefore, during insertion of the LMA because anesthesiologists do not need to worry about early emergence, they are comfortable with the doses of drugs used.…”

Prophylactic effect of ephedrine to reduce hemodynamic changes associated with anesthesia induction with propofol and remifentanil

“…[5] This combination has also been proposed to avoid complications such as anaphylactic reaction, residual curarisation and awareness, which are sometimes seen with the use of neuromuscular blocking agents during general anesthesia. [6] Using a combination of propofol and remifentanil for anesthesia induction however, may have negative synergistic effects on patient's hemodynamic status leading to bradycardia and hypotension. [5]…”

The optimal dose of remifentanil for acceptable intubating conditions during propofol induction without neuromuscular blockade

“…Stevens and Wheatley et al [6] reported that remifentanil at doses of 3.0 and 4.0 μg/kg in combination with propofol decreased postintubation HR and MAP compared with preinduction values. The decrease in MAP and HR was well tolerated in healthy patients and did not require additional treatment [13,25].…”

“…Propofol is particularly preferred over thiopental sodium or etomidate for intubation and Laryngeal Mask Airway insertion because of greater depression of pharyngeal and laryngeal reflexes. However, hypotension is an important side effect limiting the use of propofol [5,13]. The addition of opioids to propofol during tracheal intubation without using muscle relaxants prevents undesired side effects by reducing propofol dose, and also potentiates the effects of propofol.…”