Evaluation of the laryngeal mask airway for spontaneous breathing in short pediatric operation under Sevoflurane inhalation anesthesia

Abstract

Objective To evaluate the effects of the laryngeal mask airway for spontaneous breathing in short pediatric operation under Sevoflurane inhalation anesthesia. Methods Eighty children undergoing hernia surgery, of whom ASA Ⅰ or Ⅱ, in accordance with the random number table, were randomly divided into two groups(each 40 cases): the laryngeal mask airway for spontaneous breathing with Sevoflurane inhalation anesthesia in group A, and tracheal intubation for controlled ventilation with Sevoflurane inhalation anesthesia in group B. Children in the two groups were fasting for 6 hours and without drinking for 4 hours before anesthesia.Anesthesia was induced with Sevoflurane inhalation for all patients.The laryngeal mask airway was inserted soon after induction of anesthesia with Sevoflurane inhalation, and anesthesia maintained with Sevoflurane inhalation in group A. Patients in group B were given cisatracurium 0.15 mg/kg intravenous injection before tracheal intubation, and anesthesia maintained with Sevoflurane inhalation, 40 minutes before the end of the surgery to stop using muscle relaxant.Ten minutes before the end of the operation to stop Sevoflurane inhalation, in two groups.The end-tidal carbon dioxide partial pressure(PETCO2), mean blood pressure, heart rate, respiratory rate, pulse oxygen saturation and end-tidal sevoflurane partial pressure(PETSev) were recorded one minute before the induction of anesthesia, 15 min, 30 min, 45 min, and 60 min after the induction of anesthesia.Both the time to regain consciousness and the time to remove laryngeal mask airway or tracheal catheter were recorded in two groups. Results The mean blood pressure, heart rate decreased in two groups after the induction of anesthesia(P<0.05). The value of PaCO2 increased and that of base excess decreased in 30 min after the induction of anesthesia in group A(P<0.05). The value of PETCO2 increased, and that of pH decreased in 45 min after the induction of anesthesia in group A(P<0.05). The movements of the limbs and head induced by operative stimulation in group A were more than those in group B(P<0.05), but the incidences of cough and laryngospasm induced by removing the laryngeal mask airway or tracheal catheter in group B were higher than those in group A(P<0.05). Both the time to regain consciousness and the time to remove laryngeal mask airway or tracheal catheter were shorter in group A than those in group B(P<0.05). Conclusion It is safe that the laryngeal mask airway for spontaneous breathing with Sevoflurane inhalation anesthesia in short pediatric operation.The time of anesthesia is beyond half an hour during operation and the artificial respiration should be implemented. Key words: Laryngeal mask airway; Sevoflurane; Spontaneous breathing; Inhalation anesthesia; Children