2166 Delayed Symptomatic Pneumoperitoneum After Peroral Endoscopic Myotomy (POEM)

Abstract

INTRODUCTION: Per-oral endoscopic myotomy (POEM) is as an effective and safe option for the treatment of achalasia. Symptomatic pneumoperitoneum, one of the most significant adverse events noted with POEM, generally presents during the periprocedural period and is treated with needle decompression. We report two cases of delayed symptomatic pneumoperitoneum that were recognized more than 24 hours after POEM, which has not been reported previously. CASE DESCRIPTION/METHODS: A 49-year-old female with history of achalasia presented with two-year history of dysphagia, 40lb weight loss, regurgitation, and chest pain that had been refractory to multiple esophageal dilations and botulinum toxin injections. She underwent an uncomplicated POEM and was admitted for observation. On post-procedure day 2, she complained of worsening shortness of breath and abdominal pain. Chest and abdominal radiographs revealed large volume pneumoperitoneum. Due to continued progression of pain and dyspnea, as well as persistence of pneumoperitoneum on imaging, she underwent CT-guided FNA decompression on post-procedure day 4, with 660 ml of air evacuated and improvement of pain and dyspnea. A 53-year-old female with history of achalasia presented with four-month history of dysphagia, 40lb weight loss, and regurgitation. She underwent an uncomplicated POEM and was admitted for observation. Approximately four hours after the procedure, she became febrile and tachycardic, concerning for perforation. She was transferred to the ICU, where physical exam revealed crepitus to the neck and chest, as well as diffuse abdominal tenderness without guarding or rebound. A chest radiograph revealed large volume pneumoperitoneum. Gastrograffin swallow showed no evidence of contrast extravasation or perforation. On post-procedure day 1, she underwent bedside ultrasound-guided needle decompression using a 16-gauge angiocatheter, which led to a rush of air and improvement in abdominal pain. DISCUSSION: While symptomatic pneumoperitoneum is the second most common adverse event associated with POEM, it has been reported exclusively in the immediate periprocedural period. The etiology of delayed symptomatic pneumoperitoneum in these cases is unclear. No precipitating factors were identified in the first case; in the second case, it is possible that the symptoms were due to a microperforation not detected on imaging. These cases illustrate the importance of continued vigilance for this complication outside of the immediate periprocedural period.