Comparison of postoperative complication between Laryngeal Mask Airway and endotracheal tube during low-flow anesthesia with controlled ventilation

Objective: To compare the postoperative complications between Laryngeal Mask Airway [LMA] and endotracheal tube [ETT] during low-flow anesthesia with controlled ventilation

Methodology: Eighty adult Patients with ASA class I or II were randomly allocated into two forty-patient groups [ETT or LMA]. Cuff pressure was monitored during anesthesia. After high uptake period, fresh gas flow [FGF] was decreased to 1 lit/min and isoflurane set to 1%. Monitoring during anesthesia included non-invasive blood pressure, ECG, ETCO2 and pulse oximetry. System leakage [>100 ml/min], rebreathing and any attempt to increase FGF to overcome the leak were monitored during anesthesia. Later, patients were extubated and transferred to Post Anesthesia Care Unit [PACU]. In PACU, the incidence of sore throat, cough, difficulty in swallowing and shivering was monitored for all patients

Results: Leakage was observed in two and three cases in ETT and LMA groups respectively [P>0.05]. Postoperative cough, sore throat and difficulty in swallowing were significantly less in LMA than ETT group. No significant difference was observed regarding ETCo2 values between 2 groups

Conclusion: If careful measures regarding insertion techniques, correct LMA position and routine monitoring of LMA cuff pressure are taken, LMA can be used as a safe alternative with lower incidence of post operation complication compared with ETT during low-flow controlled anesthesia with modern anesthetic machines

Administration of remifentanil in establishing a more stable post-anesthesia cardiovascular status in neurosurgical procedures

Emergence from general anesthesia and especially post-extubation phase are the stages associated with cardiovascular hyperdynamic status in which patients with increased intracranial pressure [ICP] could be affected by severe cardiac and or cerebral complications. Administering remifentanil could be helpful in maintaining the hemodynamic stability at the end of the surgery and recovery stages and reducing recovery phase length. In a double-blind prospective randomized clinical trial, 60 adult patients with ASA [American Society of Anesthesiologist] class of I-II scheduled to undergo elective neurosurgery operations were randomly divided into two groups receiving remifentanil and placebo as IV infusion within four minutes prior to extubation continued by an IV infusion for 10 minutes after extubation. There was a significant difference between two groups regarding the changes of Mean Arterial Pressure after extubation and five minutes after extubation [P< 0.001].Remifentanil group compared with control group was of significant difference at all heart rate values after extubation [P< 0.001]. Remifentanil could be used in preventing hyperdynamic status throughout extubation phase without extending recovery phase length. However, administration of this medication should be performed cautiously.