High Prevalence of Gastroparesis in Post Lung Transplant Patients ACG Fellows-In-Training Award Presidential Poster

Abstract

Introduction: Gastroparesis after lung transplantation has been described, and is thought to be due to operative vagal nerve injury. By promoting aspiration, gastroparesis may predispose to bronchiolitis obliterans syndrome (BOS), a form of chronic rejection and the primary cause of allograft failure in lung transplant recipients. We aimed to determine the prevalence of post-transplant gastroparesis at our institution and to evaluate the effect of intra-pyloric botox injection on symptoms, gastric emptying, and pulmonary outcomes.Table 1: Baseline Characteristics of the Cohort Stratified by Normal (NGE) or Delayed (DGE) Gastric Emptying, with and without BotoxFigure 1Figure 2Methods: 195 post-lung transplant patients who underwent GES between 7/2003-8/2015 were placed into subgroups: normal gastric emptying (NGE), delayed gastric emptying (DGE), DGE with botox, and DGE without botox. We identified BOS occurrences and timing among each subgroup, and performed Kaplan-Meier estimation of freedom from BOS after transplant and GES. Results: DGE was found in 122 (62.6%) patients. Of these, 47 (38.5%) patients underwent a total of 70 intra-pyloric botox injections. Symptomatic improvement was seen 72.8% of the time. After botox, the absolute 2- and 4-hour % retention found on GES improved by 12.7% and 12.3%, respectively. There were no procedural complications. For patients with available pulmonary clinical data (n=147), the rates of freedom from BOS after transplant and new onset or worsening grade BOS after GES were not significantly different between NGE and DGE subgroups. However, among DGE patients (n=63) BOS occurred sooner and was more often pre-existing at time of GES (Table 2). While pyloric botox injection did not appear to prevent chronic allograft rejection after GES or transplant overall among those with DGE, freedom from BOS appeared to be significantly increased when botox was performed sooner after transplant. Of note, more BOS risk events (acute rejection and bacterial/viral pneumonia) occurred in the DGE v. NGE and botox v. no botox subgroups.Table 2: Baseline Characteristics and Pulmonary Outcomes of the Pulmonary Cohort Stratified by Normal (NGE) or Delayed (DGE) Gastric Emptying, with and without BotoxConclusion: A high prevalence of post-lung transplant gastroparesis was observed, and the majority of patients who underwent pyloric botox injections had successful symptomatic and physiologic motility response. The efficacy of pyloric botox injections in preventing BOS among post-lung transplant patients with gastroparesis remains unclear, though freedom from BOS appeared to be improved when botox was performed soon after transplant. In our cohort, risk factors other than gastric emptying may have played a larger role in the development of chronic allograft rejection.