Pharyngoesophagoplasty for Patients with Benign Intractable Pharyngoesophageal Stricture: The Daunting Task of Restoring Deglutition

Abstract

ABSTRACT Swallowing or deglutition is one of the complex functions of the body. This is often taken for granted until there is a challenge that makes this function difficult or impossible. The swallowing mechanism can be disrupted functionally or by pathological conditions of the structures that are involved in ensuring coordinated swallowing without aspiration. The anatomy of the pathway through which food masticated is delivered to the stomach is quite complex especially at the pharyngeal level. The pharynx (throat) is a muscular tunnel that connects the mouth and nose to the oesophagus and the larynx. At this level the food is no longer under voluntary control and any pathological process that disrupts the smooth and fine coordination of muscles is complicated by aspiration. One of the pathological conditions which severely disrupts the swallowing mechanism and at the same time threatens the airway is benign pharyngoesophageal strictures. This commonly occurs because of caustic ingestion and rarely, from radiation injury during treatment of head and neck tumours. Caustic injuries to the aerodigestive tract occur when individuals accidentally or intentionally (suicidal intent) ingest strong acid or alkali. In our environment, accidental ingestion of caustic soda is common and a serious public health issue. Caustic soda is a strong alkali and has devastating consequences when it encounters tissues; the chemical reaction that ensues leave behind chemical burns with necrosis that can penetrate very deep into tissues and organs. Victims who accidentally swallow this substance are mostly children of mothers or relative of these mothers who engage in local soap making. The caustic soda which is the main ingredient of local soap is often stored in familiar containers (cups or water bottles) by these mothers. The unsuspecting child, when thirsty, reaches out for this and drink before realizing he/she has swallowed a poison. Patients who swallow caustic substances destroy structures in the oral cavity, pharynx, larynx, and the oesophagus. The long-term complications of fibrosis and stricture formation destroy the normal anatomy – structural distortion, lumen obliteration from stricture and loss of coordination of these structures. The outcome of these complications is dysphagia which may be absolute for life and sometimes with obliteration of the normal airway. Most patients suffer these complications downstream in the oesophagus, but a few about 0.6% to 24% of these patients have complications at the level of the pharynx. Restoring gastrointestinal continuity in patients with caustic and radiation injury at the level of the pharynx (pharyngoesophageal strictures) is a dauting task all over the world. The challenge is at the pharyngeal phase where the anatomy is shared by the airway and the path for food. This is well coordinated to regulate the safety of the airway during swallowing. Repair of a stricture at this level to restore gastrointestinal continuity and preserve normal functioning of the airway is the struggle for most surgeons all over the world. Repair is complicated by aspiration whenever the patient attempts to eat and often takes weeks to overcome with physiotherapy. An unsuccessful correction may commit these patients to feeding through a gastrostomy tube with or without tracheostomy for life. Currently, no standard procedure is prescribed for strictures involving the pharynx. The National Cardiothoracic Center since 2006 started research into the management of these complex pharyngoesophageal injuries resulting from caustic ingestion. The demonstration lecture I delivered on the 20th of May 2011 as part of the procedure for my appointment as a lecturer in the University of Ghana Medical School, was my initial research work in patients with complex pharyngoesophageal strictures. The first article of work done in this regard was published by the Interactive Cardiovascular and Thoracic Surgery titled ‘Colopharyngoplasty for intractable caustic pharyngoesophageal stricture in an indigenous African community – adverse impact of concomitant tracheostomy outcome’ The conclusion was ‘In this African community (Ghana), colopharyngoplasty provided an effective means of restoration of upper digestive tract continuity in patients with severe caustic pharyngoesophageal strictures. Tracheostomy in this setting portends a significant long term mortality risk.’ Some of the patients operated who needed tracheostomy to protect the air way or presented with permanent tracheostomy suffered complications from the tracheostomy that resulted in their death. Tracheostomy care in the country has some challenges, especially in the poor. We were motivated to work on a procedure that will eliminate the use of tracheostomy in patients with severe pharyngoesophageal stricture with destroyed supraglottic apparatus. The search for a solution gave birth to the procedure I termed Colon- Flap Augmentation Pharyngoesophagoplasty (CFAP). More than 20 patients have benefited from this procedure with excellent outcomes. In this lecture, Professor Mark Tettey will provide in-depth knowledge of the aetiopathogenesis of caustic destruction of tissues, the different presentations of the devastating effect of complications of caustic ingestion and different procedures currently used in the management of these complications. The innovative procedure developed at the National Cardiothoracic Center and a classification of pharyngoesophageal strictures yet to be published will be presented. The classification is meant to help identify the different presentations and the surgical options available for optimal treatment.