Principles Of Surgical Therapy
Compound light microscopes are just examples of microscopes used in the medical field today. These compound light microscopes aid clinicians and surgeons in tissue assessment, magnification and disease diagnosis. Esophageal tissue samples can be sent to the laboratory for biopsy and further studies with the use of compound light microscopes to rule out other differential diagnosis.
The primary goal of antireflux surgery is to safely restore the structure of the sphincter or to prevent it’s shortening with gastric distention, while preserving the patient’s ability to swallow normally, to belch to relieve gaseous distention, and to vomit when necessary. Regardless of the choice of the procedure, this goal can be achieved if attention is paid to five principles in reconstructing the cardia. First, the operation should restore the pressure of the distal esophageal sphincter to a level twice resting gastric pressure (i.e., 12 mm Hg for a gastric pressure of 6 mm Hg), and its length to at least 3 cm. This not only augments sphincter characteristics in patients in whom they are reduced prior to surgery, but also prevents unfolding of a normal sphincter in response to gastric distention. Preoperative and postoperative esophageal manome¬try measurements have shown that the resting sphincter pressure and the overall sphincter length can be surgically augmented over preoperative values, and that the change in the former is a function of the degree of gastric wrap around the esophagus.
Second, the operation should place an adequate length of the distal esophageal sphincter in the positive-pressure environment of the abdomen by a method that ensures its response to changes in intra-abdominal pressure. The permanent restoration of 1.5 to 2 cm of abdominal esophagus in a patient whose sphincter pressure has been augmented to twice resting gastric pressure will maintain the competency of the cardia over various challenges of intra-abdominal pressure. All three of the popular antireflux procedures increase the length of the sphincter exposed to abdominal pressure by an aver¬age of 1 cm. When poorly performed, however, an operation may result in a reduction of the length of abdominal sphincter. Increasing the length of sphincter exposed to abdominal pressure will improve competency only if it is acted on by challenges of intra-abdominal pressure. The creation of a conduit that will ensure the transmission of intra-abdominal pressure changes around the abdominal portion of the sphincter is a necessary aspect of surgical repair. The fundo¬plication in the Nissen and Belsey repairs serves this purpose.
Third, the operation should allow the reconstructed cardia to relax on deglutition. In normal swallowing, a vagally mediated re¬laxation of the distal esophageal sphincter and the gastric fundus occurs. The relaxation lasts for approximately 10 seconds and is followed by a rapid recovery to the former tonicity. To ensure re¬laxation of the sphincter, three factors are important: (1) only the fundus of the stomach should be used to buttress the sphincter, since it is known to relax in concert with the sphincter; (2) the gastric wrap should be properly placed around the sphincter and not incorporate a portion of the stomach or be placed around the stomach itself, since the body of the stomach does not relax with swallowing; and (3) damage to the vagal nerves during dissection of the thoracic esophagus should be avoided because it may result in failure of the sphincter to relax.
Fourth, the fundoplication should not increase the resistance of the relaxed sphincter to a level that exceeds the peristaltic power of the body of the esophagus. The resistance of the relaxed sphincter depends on the degree, length, and diameter of the gastric fundic wrap, and on the variation in intra-abdominal pressure. A 360-degree gastric wrap should be no longer than 2 cm and constructed over a 60F bougie. This will ensure that the relaxed sphincter will have an adequate diameter with minimal resistance. This is not necessary when constructing a partial wrap.
Fifth, the operation should ensure that the fundoplication can be placed in the abdomen without undue tension, and maintained there by approximating the crura of the diaphragm above the repair. Leaving the fundoplication in the thorax converts a sliding hernia into a paraesophageal hernia, with all the complications associated with that condition. Maintaining the repair in the abdomen under tension predisposes to an increased incidence of recurrence. This can occur in patients who have a stricture or Barrett’s esophagus, and is due to shortening of the esophagus from the inflammatory process. This problem can be resolved by lengthening the esophagus by gastroplasty and constructing a partial fundoplication.
Procedure Selection
A laparoscopic approach is used in patients with normal esophageal contractility and length. Patients with questionable esophageal length may be best approached transthoracically, where full esophageal mobilization serves as a lengthening procedure. Those with a failed esophagus characterized by absent esophageal contractions and/or absent peristalsis such as those with scleroderma are best treated either medically or with a partial fundoplication in order to avoid the increased outflow resistance associated with a complete fundoplication. If the esophagus is short after it is mobi¬lized from diaphragm to aortic arch, a Collis gastroplasty is done to provide additional length and avoid placing the repair under tension. In the majority of patients who have good esophageal contractility and normal esophageal length, the laparoscopic Nissen fundoplication is the procedure of choice for a primary antireflux repair. Experience and randomized studies have shown that the Nissen fun¬doplication is an effective and durable antireflux repair with minimal side effects that provides long-lasting relief of reflux symptoms in over 90% of patients.
