NTRODUCTION: Many operative factors have been associated with the development of dysphagia after laparoscopic Nissen (LN), however its etiology remains unclear. No study to date has identified a reliable means to preoperatively predict those at increased risk. The aim of this study is to determine if preoperative physiologic factors can account for postoperative dysphagia and whether it can be reliably predicted.
METHODS: One hundred sixty three patients with documented GERD by 24 hour pH testing underwent LN, median age 48 years (range 15 to 78), 119 (73%) males and 44 (27%) females. A previously published uniform operative technique was performed in all patients. Median follow up was 14 mo. (range 6 to 81). The presence or development of postoperative dysphagia more than 6 mo after LN was scored (0-3). Preoperative variables: age, sex, esophageal and LES manometric characteristics, ambulatory pH, endoscopic findings and preoperative symptoms were analyzed.
RESULTS: Dysphagia was present in 37% (60/163) prior to surgery and 8% (13/163) postoperatively. Preoperative dysphagia was relieved in all but 5 patients (92%). In those patients without preoperative dysphagia, 8/103 (8%) developed new onset dysphagia. Of these, 5 (63%) had normal LES pressure and length (cLES). New onset dysphagia was significantly more common in patients with a cLES (22% v 4%, p=0.01). Patients with a cLES had almost a six-fold increase in the risk of developing dysphagia as those with an iLES (RR=5.8). Preoperative LESP alone was also associated with the development of dysphagia (p=0.04), the severity of which increased as LESP increased (p=0.007). Previous studies have demonstrated that high mean residual pressures relate to dysphagia. In this study, preoperative LESP correlated with postoperative LESP (r=0.48, p=0.01) and with mean residual pressure (r=0.33, p=0.05) offering insight into the mechanism of this dysphagia.
CONCLUSION: This study reports, for the first time, the novel observation that preoperative physiologic parameters do play a role in the development of dysphagia after LN, and that LES characteristics can be used to predict those at risk. Patients with high LESP or a cLES are at increased risk for postoperative dysphagia and should be made aware of this possibility before LN. The mechanism of this dysphagia appears to be increased esophageal outflow resistance secondary to raised LES residual pressures.