GASTROESOPHAGEAL REFLUX DURING ANESTHESIA IN THE DOG - THE EFFECT OF PREOPERATIVE FASTING AND PREMEDICATION

Lower oesophageal pH was monitored in 240 anaesthetised The study desc ribed here was carried out to monitor lower dogs. The incidence of gas tro-oesophageal reflux was 16.3 per oesophageal pH during anaesthesia in dogs and to correlate the cent and most of the reflux episodes occu rred shortly after the occurrence of gastro-oesophageal reflux with th e duration of preinduction of anaesthesia, The refluxate was nearly al ways acid operative fasting or the administration of various preanaest hetic (pH<4.0), but in 10.3 per cent of the cases it was alkaline agen ts. (pH>7.5); gastric contents of pH below 2.5 were refluxed on 19 occ asions (7.9 per cent). Regurgitation occurred in only one dog. Prolong ing preoperative fasting was associated with an Materials and methods increased incidence of reflux and increased gastric acidity. Premedica tion with diazepam was associated with fewer were reflux episodes than premedication with atropine and propi- used. They were all clinical c ases admitted to the University of onylpromazine.