Relief from respiratory symptoms can be expected in approximately what percent of patients with reflux associated asthma with medical therapy:
Once the diagnosis is established, treatment may be initiated with either proton pump inhibitor (PPI) therapy or antireflux surgery. A trial of high-dose PPI therapy may help establish the facts that reflux is partly or completely responsible for the respiratory symptoms. It is important to note that the persistence of symptoms in the face of aggressive PPI treatment does not necessarily rule out reflux as a possible cofactor or sole etiology. Although there is probably some elements of a placebo effect, relief of respiratory symptoms can be anticipated in up to 50% of patients with reflux-induced asthma treated with antisecretory medications. However, when examined objectively, <15% of patients can be expected to have improvement in their pulmonary function with medical therapy. In properly selected patients, antireflux surgery improves respiratory symptoms in nearly 90% of children and 70% of adults with asthma and reflux disease. Improvements in pulmonary function can be demonstrated in around 30% of patients. Uncontrolled studies of the two forms of therapy (PPI and surgery) and the evidence from the two randomized controlled trials of medical versus surgical therapy indicate that surgical valve reconstruction is the most effective therapy for reflux-induced asthma. The superiority of the surgery over PPI is most noticeable in the supine position, which corresponds with the nadir of PPI blood levels and resultant acid breakthrough and is the time in the circadian cycle when asthma symptoms are at their worst.
All of the following patients are good candidates for antireflux surgery EXCEPT:
Studies of the natural history of GERD indicate that most patients have a relatively benign form of the disease that is responsive to lifestyle changes and dietary and medical therapy, and do not need surgical treatment. Approximately 25 to 50% of the patients with GERD have persistent or progressive disease, and it is this patient population that is best suited to surgical therapy. In the past, the presence of esophagitis and a structurally defective LES were the primary indications for surgical treatment, and many internists and surgeons were reluctant to recommend operative procedures in their absence. However, one should not be deterred from considering antireflux surgery in a symptomatic patient with or without esophagitis or a defective sphincter, provided the disease process has been objectively documented by 24-hour pH monitoring. This is particularly true in patients who have become dependent upon therapy with PPis, or require increasing doses to control their symptoms. It is important to note that a good response to medical therapy in this group of patients predicts an excellent outcome following antireflux surgery.
In general, the key indications for antireflux surgery are (a) objectively proven gastroesophageal reflux disease, and (b) typical symptoms of gastroesophageal reflux disease (heartburn and/or regurgitation) despite adequate medical management, or (c) a younger patient unwilling to take lifelong medication. In addition, a structurally defective LES can also predict which patients are more likely to fail with medical therapy. Patients with normal sphincter pressures tend to remain well controlled with medical therapy, whereas patients with a structurally defective LES may not respond as well to medical therapy, and often develop recurrent symptoms within 1 to 2 years of beginning therapy. Such patients should be considered for an antireflux operation, regardless of the presence or absence of endoscopic esophagitis.
Preoperative testing for antireflux surgery typically includes all of the following EXCEPT:
Before proceeding with an antireflux operation, several factors should be evaluated. The clinical symptoms should be consistent with the diagnosis of gastroesophageal reflux. Patients presenting with the typical symptoms of heartburn and/or regurgitation who have responded, at least partly, to PPI therapy, will generally do well following surgery, whereas patients with atypical symptoms have a less predictable response. Reflux should also be objectively confirmed by either the presence of ulcerative esophagitis or an abnormal 24-hour pH study.
The propulsive force of the body of the esophagus should be evaluated by esophageal manometry to determine if it has sufficient power to propel a bolus of food through a newly reconstructed valve. Patients with normal peristaltic contractions can be considered for a 360° Nissen fundoplication or a partial fundoplication, depending on patient and surgeon preferences. When peristalsis is absent a partial fundoplication is probably the procedure of choice, but only if achalasia has been ruled out.
Hiatal anatomy should also be assessed. In patients with smaller hiatal hernias endoscopy evaluation usually provides sufficient information. However, when patients present with a very large hiatus hernia or for revision surgery after previous antireflux surgery, contrast radiology provides better anatomical information. The concept of anatomic shortening of the esophagus is controversial, with divergent opinions held about how common this problem is. Believers claim that anatomic shortening of the esophagus compromises the ability of the surgeon to perform an adequate repair without tension, and that this can lead to an increased incidence of breakdown or thoracic displacement of the repair. Some of those who hold this view claim that esophageal shortening is present when a barium swallow X-ray identifies a sliding hiatal hernia that will not reduce in the upright position, or that measures more than 5 em in length at endoscopy. When identified these surgeons usually undertake add a gastroplasty to the antireflux procedure. Others claim that esophageal shortening is overdiagnosed and rarely seen, and that the morbidity of adding a gastroplasty outweighs any benefits. These surgeons would recommend a standard antireflux procedure in all patients undergoing primary surgery.
The valve created during an antireflux procedure should be at least:
The primary goal of antireflux surgery is to safely create a new antireflux valve at the gastroesophageal junction (GEJ), while preserving the patient's ability to swallow normally and to belch to relieve gaseous distention. Regardless of the choice of the procedure, this goal can be achieved if attention is paid to some basic principles when reconstructing the antireflux mechanism. First, the operation should create a flap valve which prevents regurgitation of gastric contents into the esophagus. This will result in an increase in the pressure of the distal esophageal sphincter region. Following a Nissen fundoplication, the expected increase is to a level twice the resting gastric pressure (ie, 12 mm Hg for a gastric pressure of 6 mm Hg). The extent of the pressure rise is often less following a partial fundoplication, although with all types of fundoplication the length of the reconstructed valve should be at least 3 em. This not only augments sphincter characteristics in patients in whom they are reduced before surgery, but prevents unfolding of a normal sphincter in response to gastric distention. Preoperative and postoperative esophageal manometry 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. However, the aim of any fundoplication is to create a loose wrap, and to maintain the position of the gastric fundus close to the distal intra-abdominal esophagus, in a flap valve arrangement. The efficacy of this relies on the close relationship between the fundus and the esophagus, not the "tightness" of the wrap.
A Toupet fundoplication involves:
Partial fundoplications were developed as an alternative to the Nissen procedure in an attempt to minimize the risk of postfundoplication side effects, such as dysphagia, inability to belch, and flatulence. The commonest approach has been a posterior partial or Toupet fundoplication. Some surgeons use this type of procedure for all patients presenting for antireflux surgery, whereas others apply a tailored approach in which a partial fundoplication is constructed in patients with impaired esophageal motility, in which the propulsive force of the esophagus is thought to be insufficient to overcome the outflow obstruction of a complete fundoplication. The Toupet posterior partial fundoplication consists of a 270° gastric fundoplication around the distal 4 em of esophagus. It is usually stabilized by anchoring the wrap posteriorly to the hiatal rim.
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