Continuous monitoring of oesophageal pH during general anaesthesia with laryngeal mask airway in children

We studied the incidence of gastro-oesophageal reflux (GOR) during general anaesthesia with the laryngeal mask airway (LMA) in a paediatric population with two ventilatory regimes: spontaneous breathing and controlled mechani cal ventilation (CMV). Thirty children between 6 months and 15 years, ASA I -II, for routine surgery, were randomly assigned in two groups: spontaneous ventilation (n=14), and CMV (n=16). A pH probe was situated in the central third of the oesophagus. Some 66% of the patients breathing spontaneously had GOR episodes vs. 92% of the patients with CMV (P < 0,01). Reflux took p lace mainly after LMA removal (21% vs. 68%; P < 0,01) and in the Postanaest hetic Care Unit (PACU) (29% vs. 43%; P < 0,05). There was a high incidence of GOR during general anaesthesia and in the PACU in paediatric patients an aesthetized with the LMA. GOR episodes were significantly more evident in t he CMV group, mainly after LMA removal, but without clinical significance.