Assessment of Positive Pressure Controlled Ventilation with the Laryngeal Mask Airway.
- Author:
Young Soon LIM
1
;
Sang Kyi LEE
Author Information
1. Department of Anesthesiology Chonbuk National University Medical School, Chonju, Korea.
- Publication Type:Original Article
- Keywords:
Airway;
laryngeal mask airway;
Ventilation;
positive pressure ventilation
- MeSH:
Adult;
Airway Resistance;
Anesthesia;
Compliance;
Humans;
Intubation, Intratracheal;
Laryngeal Masks*;
Neuromuscular Blockade;
Positive-Pressure Respiration;
Reflex;
Tidal Volume;
Ventilation*
- From:The Korean Journal of Critical Care Medicine
1999;14(2):148-153
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGOUND: Cuff overinflation may cause premature rejection of the laryngeal mask airway (LMA) or provocation of incomplete and ineffective reflex responses. Therefore a previous report recommends that the cuff is inflated to a pressure of 60 cmH2O to minimize side effects. The objective of this study was to assess the possibility of controlled positive pressure ventilation in adults when intra-cuff pressure of LMA was set to 60 cmH2O. METHODS: We studied 20 adult patients who received general inhalational anesthesia with LMA and mechanical positive pressure ventilation for gynecological operations. The following variables was determined during anesthesia at two time points 3 min after endotracheal intubation and 5 min before neuromuscular blockade: pop-off pressure, tidal volume, peak-air way pressure, plateau pressure, compliance, SpO2, and ETCO2. RESULTS: Mean compliances measured were normal. Mean airway pressures (peak, plateau) were 13.6 and 15.1 cmH2O at two time points respectively while setting the tidal volume with 10 ml/kg. However, pop-off pressure were 18.3 and 20.1 cmH2O, respectively. Mean tidal volumes without gas leak around the LMA cuff were 14.5 and 14.5 ml/kg, respectively. Mean SpO2 and mean ETCO2 were measured 99.0 and 99.2%, 31.3 and 30.3 mmHg in two time points, respectively. CONCLUSIONS: The study suggested that controlled mechanical positive pressure ventilation using the laryngeal mask airway with 60 cmH2O intra-cuff pressure were be adequate when pulmonary compliance and airway resistance were normal.
