Peroral Endoscopic Myotomy (POEM) is a minimally invasive treatment for swallowing disorders, most commonly achalasia. Achalasia is a condition where the lower esophageal sphincter, a ring of muscle between the esophagus and the stomach, fails to relax properly, making it difficult for food and liquids to pass through. POEM offers an effective, incisionless alternative to traditional surgical treatments. The procedure is performed entirely through the mouth using a flexible endoscope, eliminating the need for external incisions. This modern approach has become a preferred option, offering comparable results to surgery with a potentially faster recovery.
Understanding the POEM Procedure
The POEM procedure is a sophisticated endoscopic technique performed under general anesthesia, focusing on selectively cutting the muscle fibers that are too tight. The patient is typically positioned on their back to facilitate the procedure and manage the carbon dioxide gas used for insufflation. The process begins with the careful insertion of a specialized endoscope, a thin, flexible tube equipped with a camera and surgical tools, into the esophagus.
Once the endoscope is in place, the surgeon creates a small mucosal incision, a cut in the inner lining of the esophagus, usually about 10 to 15 centimeters above the junction with the stomach. This incision serves as the entry point into the submucosal space, which lies just beneath the inner lining. The surgeon then meticulously dissects the tissue to create a long, narrow submucosal tunnel that extends down toward the stomach.
Creating the submucosal tunnel allows the surgeon to safely access the inner circular muscle layer of the esophagus and the lower esophageal sphincter. The myotomy, which is the muscle-cutting part of the procedure, is then performed using electrosurgical instruments passed through the endoscope. This involves dividing the thickened circular muscle fibers that are responsible for the obstruction.
The myotomy is extended approximately 2 to 3 centimeters into the gastric side of the junction to ensure the entire lower esophageal sphincter muscle is fully relaxed. A standard myotomy length is typically about 10 centimeters. After the muscle is divided, the endoscope is withdrawn, and the initial mucosal incision is closed securely using small endoscopic clips, sealing the tunnel and completing the procedure.
Factors Determining the Length of POEM Surgery
The actual time spent in the operating room for a POEM procedure generally ranges from 60 to 120 minutes. Studies have shown the average procedural time to be around 75 minutes, but this is highly variable and depends on a number of patient and procedural factors.
One significant factor is the specific type of achalasia the patient has, as classified by high-resolution manometry. Patients with Type III achalasia, which involves spastic, vigorous contractions of the esophageal body, often require a longer myotomy that extends further up the esophagus. This more extensive muscle cutting can lengthen the procedure time, often requiring a myotomy of 14 centimeters compared to the 10-centimeter length often used for non-spastic types.
The patient’s unique anatomy also influences the complexity and duration of the procedure. For instance, an esophagus that has become significantly dilated and tortuous over time, sometimes called a sigmoid esophagus, can make navigating the endoscope and creating the straight submucosal tunnel more challenging. Furthermore, patients who have had prior treatments, such as repeated pneumatic dilation or botox injections, may have scarring that makes the tissue dissection more difficult and time-consuming.
The surgeon’s experience level is another major determinant of efficiency. Physicians who perform POEM regularly tend to have shorter operating times due to increased familiarity with the intricate steps. Unexpected events, such as bleeding from submucosal vessels during the tunneling phase, or a small perforation of the mucosal layer, require immediate and careful management, which can extend the overall procedure time.
The Immediate Post-Procedure Timeline
Once the POEM procedure is complete, the patient is immediately moved to a recovery room where they are closely monitored as they wake up from general anesthesia. During this initial phase, the medical team manages any immediate post-operative discomfort, which is often described as a sore throat or mild chest pain. Patients are typically kept nothing-by-mouth for the remainder of the day.
The hospital stay following POEM is notably short, often lasting only one to two days. The morning after the procedure, a diagnostic swallow test, usually an esophagram, is performed. This involves the patient swallowing a contrast material while X-rays are taken to ensure there are no leaks from the closure site and to confirm that the contrast passes easily into the stomach.
If the esophagram shows no evidence of a leak, the patient is allowed to begin a clear liquid diet. The dietary progression is gradual to allow the esophagus to heal properly, starting with clear liquids and advancing to full liquids and then soft foods over the course of the first week or two. Patients are discharged with instructions to maintain this soft diet for a period before slowly reintroducing solid foods.
Patients are often prescribed a course of antibiotics and a proton pump inhibitor medication to aid in the healing process and manage any potential post-procedure acid exposure. Although the surgical time is short, the full recovery timeline, including the dietary restrictions, spans approximately ten days to two weeks before a patient can return to a normal diet and full activity level.