Can EndoFLIP Improve Quality of Life Before and After Fundoplication?

Gastroesophageal reflux disease (GERD) has a prevalence of 30% in North America (Richter 2018), where patients can present with reflux, heartburn, dysphagia, chest pain, or a combination of symptoms. Those referred by their primary care physician to a specialist have often already failed a trial of proton pump inhibitors (PPI), thus warranting further investigation. Practice guidelines from the American College of Gastroenterologists (Katz 2013) recommend that patients undergo upper endoscopy, followed by esophageal manometry, and reflux monitoring before any surgical intervention.

While these recommendations are well-founded, patient compliance with these tests remains low, since esophageal manometry and 24-hour pH testing are generally poorly tolerated, involving the placement of probes inserted nasogastrically. A qualitative study investigated patient perceptions of 24-hour pH monitoring and manometry testing (Walamies 2002) and asked 92 patients to describe their experience with manometry. Of the 84 respondents, 52% reported moderate-severe discomfort. It was shown that many patients are fearful and anxious about these tests. Some may refuse them due to their invasiveness, especially if having already undergone endoscopic evaluation. Undergoing surgery with an indeterminate diagnosis or in the absence of a full motility assessment is contraindicated by current practice guidelines and devastating consequences could occur. The lack of preoperative investigations could omit a large subset of potential surgical candidates or even lead to anti-reflux surgery in patients for the wrong diagnosis.

Once a patient is considered a surgical candidate, operative management aims to reestablish the anti-reflux barrier by plicating the gastric fundus around the gastroesophageal junction (GEJ), called fundoplication. Until now, there is no established objective measure to determine how tight to make the fundoplication. Some surgeons use a bougie to estimate the diameter of the GEJ (Patterson 2000), while some use an endoscope, and others rely on their subjective judgement. A fundoplication that is too narrow can cause severe postoperative dysphagia symptoms, whereas one that is too loose may cause recurrence or worsening of GERD symptoms. A balance is required.

The EndoFLIP balloon catheter allows users to measure the cross-sectional area (CSA), diameter, pressure and distensibility index (DI) of the GEJ. This can be done intraoperatively to obtain objective measures of the tightness of the fundoplication. These results may then be correlated with post-operative symptoms to determine the optimal CSA and DI in fundoplication. Previous studies have sought to address this problem but were limited by their lack of standardized EndoFLIP use (Su 2019). Symptom severity measurements were also captured too early in the post-operative period before a new baseline was established (Nwokedi 2020). This proposed study will have a defined EndoFLIP protocol that will be used to obtain all measurements. In addition, our post-operative readings will be captured no earlier than four months from the date of surgery. The investigators attempt to establish objective measurements to guide future operative interventions, thereby improving postoperative symptoms and overall patient satisfaction.

During the pre-operative workup, most patients with a clinical indication for 24-hour pH monitoring and manometry testing will undergo an esophagogastroduodenoscopy (EGD). This is much better tolerated, allowing for the administration of topical anesthetic and intravenous sedating medications. EndoFLIP readings can be taken at the time of EGD, thereby decreasing the number of investigations that may prolong preoperative workup. Clinicians may be able to rely on these readings alone in select patients.