EFFECT OF INTRAOPERATIVE MANIPULATION AND ANESTHESIA ON LOWER ESOPHAGEAL SPHINCTER FUNCTION DURING FUNDOPLICATION

The variables influencing the intraoperative measurement of lower oeso phageal sphincter (LOS) pressure and a new method of assessing the eff ect of a fundal wrap on LOS function were investigated in 13 patients undergoing fundoplication. All patients had a 360 degrees wrap fashion ed around a 50-Fr bougie; four also underwent highly selective vagotom y. The effect of the fundal wrap, independent of LOS pressure, was ass essed by inducing LOS relaxation with balloon distension. Preoperative mean(s.e.m.) LOS pressure (14.1(2.6) mmHg) did not correlate with tha t at the start of operation (11.5(1.5) mmHg). After mobilization of th e oesophagus mean(s.e.m.) LOS pressure increased significantly (to 19. 8(2.0) mmHg; P < 0.0005) and oesophageal distension elicited LOS relax ation on 16 of 33 occasions. After completion of the wrap there was no further increase in LOS pressure, but LOS relaxation occurred after o nly five of 33 distensions (P < 0.01). These findings indicate that an aesthesia and intraoperative manipulation during fundoplication have s ignificant effects on LOS function that detract from the validity of i ntraoperative assessment. They question the rationale of current appro aches to intraoperative manometry for the assessment of antireflux sur gery.