Effect of Nissen fundoplication operation on the competence of the lower esophageal sphincter.

The results of Nissen fundoplication operation were evaluated in 12 patients with hiatus hernia and gastroesophageal reflux before and 3, 6, and 12 months after the operation. Excellent clinical results as evidenced by absence of dysphagia, esophagitis, and radiological signs of reflux were obtained in 11 patients. One year after operation one patient developed renewed reflux and slight esophagitis, probably due to sliding of the fundoplication. The resting pressure of the lower esophageal sphincter (LES) increased from 5.4 +/- 5.8 cm H2O (mean +/- S.D.) before the operation to 11.8 +/- 5.0 cm H2O 3 months after operation (p less than 0.01). At 6 and 12 months the mean resting pressure (9.5 +/- 4.6 and 8.0 +/- 3.9 cm H2O, respectively) was not significantly different from the preoperative value. Compared with the preoperative LES pressure after pentagastrin stimulation (10.8 +/- 13.9 cm H2O) the pressure 3 months after operation had increased to 33.6 +/- 11.7 (p less than 0.001), after 6 months to 21.6 +/- 7.0 (0.05 greater than p greater than 0.02, and after 12 months to 22.1 +/- 9.0 cm H2O (0.05 greater than p greater than 0.02). In two patients the stimulated pressure decreased after 6 and 12 months; both are completely free of symptoms. We suggest that assessment of the competence of the LES after fundoplication by pressure measurement is of limited value.