Does gastric sleeve surgery increase intra-gastric pressure? The short answer to this question is unknown. There are no studies I am aware of that compare the gastric pressure before and after gastric sleeve surgery. Furthermore, intra-gastric pressure varies greatly throughout the day and depends on several factors like gastric wall compliance, gastric volume and content, pyloric contractions…
Gastric fundus is the most compliant part of the stomach and is resected during sleeve gastrectomy. Consequently, it is possible that gastric wall compliance decreases after sleeve gastrectomy leading to increased intra-gastric pressure. However, gastric emptying also increases following gastric sleeve surgery and therefore the integrated intra-gastric pressure may not significantly increase.
The assumption of increased intra-gastric pressure was introduced by several bariatric surgeons trying to explain sleeve gastrectomy staple line leak rate at the angle of Hiss area. It was assumed that gastric sleeve surgery leads to increased intra-gastric pressure. Increased luminal pressure not only results in leak development but also it delays and sometimes prevents healing. Such assumptions, however, have never been proven. Narrowing at the incisura angularis may cause increased intra-gastric pressure leading to increased staple line leak rate. However, a wide incisura angularis is unlikely to be associated with increased intra-gastric pressure. Therefore, a well performed sleeve gastrectomy is most likely associated with normal intra-gastric pressure, lower staple line leak rate, and lower incidence acid reflux. Indeed, a well performed gastric sleeve surgery may be associated with decreased intra-gastric pressure. Studies are needed to evaluate intra-gastric pressure before and after sleeve gastrectomy. New tools need to be developed to study gastric wall compliance, gastric volume and intra-gastric pressure. A silicon covered electronic chip attached to the gastric mucosa may deliver such information over several days like a pH Bravo capsule.