Auswirkungen einer neuromuskulären Blockade auf den Leckagedruck der ProSeal®-Larynxmaske

Background: The ProSeal®-Laryngeal mask airway (PLMA) is increasingly used for surgical procedures that might require the intraoperative use of neuromuscular blocking agents. The airway seal of the PLMA depends on the interplay of the surrounding soft tissue of the neck and the cuff of the mask. An intraoperative neuromuscular blockade could lead to a decrease of the airway leak pressure (Pleak) secondary to the relaxation of the muscles of the neck. With this study we tested the hypothesis that a neu− romuscular blockade can result in a decreased Pleak of the PLMA. Methods: The Pleak of the PLMAwas studied in 73 female patients under total intravenous anaesthesia with propofol (0,1-0,15 mg/kg/min) and remifentanil (0,1-0,3 mg/kg/min) before and after a complete neuromuscular blockade produced by intra− venous injection of 0.6 mg/kg Rocuronium. Results: The Pleak decreased by more than 10% of the baseline Pleak in 8 out of 73 patients (11%); however, in the entire study population there was no significant difference between the mean baseline Pleak (28,5 +/- 7,3 cm H2O) and the mean Pleak after complete neuromus− cular blockade (29,1 +/- 7,0 cm H2O); (p = 0,128). Conclusion: No general correlation between application of a neuromuscular blocking agent and a decrease of the mean Pleak was found. How− ever, the decrease of the Pleak by more than 10% in 11% of the pa− tients shows that in certain patients the application of neuro− muscular blocking agents can result in a decreased Pleak of the PLMA and indicates the necessity to control the Pleak of the PLMA under complete muscle paralysis preoperatively when neuromuscular blocking agents are used.