Assessment of esophageal body and gastric function

The presence of poor esophageal body function can impact the likelihood of relief of regurgitation, dysphagia, and respiratory symptoms following surgery and may influence the decision to undertake a partial rather than a complete fundoplication. When peristalsis is absent or severely disordered, many would opt for a partial fundoplication, although recent studies would suggest a complete fundoplication may be appropriate even in this setting. The less favorable response of atypical, compared with typical, reflux symptoms after fundoplication may be related to persistent poor esophageal propulsive function and the continued regurgitation of esophageal contents.
The function of the esophageal body is assessed with esophageal manometry. This is performed with five pressure transducers located in the esophagus. To standardize the procedure the most proximal pressure transducer is located 1 cm below the well-defined cricopharyngeal sphincter. With this method a pressure response along the entire esophagus can be obtained during one swallow. The study consists of recording ten standard wet swallows with 5 mL of water. Amplitude, duration, and morphology of contractions following each swallow are all calculated at the five discrete levels within the esophageal body. The delay between onset or peak of esophageal contractions at the various levels of the esophagus is used to calculate the speed of wave propagation and represents the degree of peristaltic activity.
Esophageal disorders are frequently associated with abnormalities of duodenogastric function. Symptoms suggestive of gastroduodenal pathology include nausea, epigastric pain, anorexia, and early satiety. Abnormalities of gastric motility or increased gastric acid secretion can be responsible for increased esophageal exposure to gastric juice. If not identified before surgery, unrecognized gastric motility abnormalities are occasionally unmasked by an antireflux procedure, resulting in disabling postoperative symptoms. Considerable experience and judgment are necessary to identify the patient with occult gastroduodenal dysfunction. The surgeon should maintain a keen awareness of this possibility and investigate the stomach given any suggestion of problems. Tests of duodenogastric function that are helpful when investigating the patient with GE reflux include gastric emptying studies, gastric acid analysis, 24-hour gastric pH monitoring, and ambulatory bilirubin monitoring of the esophagus and stomach.
Poor gastric emptying or transit can provide for reflux of gastric contents into the distal esophagus. Standard gastric emptying studies are performed with radionuclide-labeled meals. They are often poorly standardized and difficult to interpret. Emptying of solids and liquids can be assessed simultaneously when both phases are marked with different tracers. After ingestion of a labeled standard meal, gamma camera images of the stomach are obtained at 5- to 15-minute intervals for 1.5 to 2 hours.
After correction for decay, the counts in the gastric area are plotted as percentage of total counts at the start of the imaging. The resulting emptying curve can be compared with data obtained in normal volunteers. In general, normal subjects will empty 59% of a meal within 90 minutes.