Impact of Enteral Feeding Approaches on Chyle Leaks in Oesophageal Cancer Surgery

What is the purpose of the study? Oesophagectomy (surgery to remove a cancerous portion of the oesophagus or gullet) is the cornerstone of treating oesophageal cancer. In recent years, minimally invasive techniques, including robotic assisted oesophagectomy have been introduced. These techniques reduce stress on patients, reduce pain, reduce the length of stay in hospital after their operation, without compromising cancer outcomes (and in some cases improving cancer outcomes). Any surgery carries the risk of complications. One complication that may arise with oesophagectomy is an increase in chyle leaks. Chyle is a fluid produced by the body that helps transport nutrients from the bowel to the bloodstream to allow them to be absorbed and processed. One of the channels that transports chyle, the thoracic duct, is divided as part of an oesophagectomy. Although it is clipped to reduce the risk of chyle leak, this may still occur, in up to 25% of operations. If a chyle leak occurs, a drainage tube needs to remain in the chest for a number of days, there may be alterations in the use of feeding techniques, and in a small portion of cases, there may need to be an operation to stop a leak, or a procedure in the radiology department. The goal of this study is to see whether use of a different type of post-operative feed (medium chain triglyceride or MCT feeds) can reduce the rate of chyle leak. This is already used to treat chyle leaks, and the question is whether using this as the routine post-operative feed can reduce rates of chyle leakage.

What will happen during the study? The oesophagectomy will proceed as planned. As part of all minimally invasive oesophagectomies, a feeding tube will be placed into the small bowel (feeding jejunostomy). This will be used to support feeding and nutrition in the post-operative period. As standard, the investigators also place a drainage tube in the right chest to drain fluid post-operatively. If the patient is recovering well, the investigators will begin feeding on the first day post-operative day. This will either be with the currently used feed (Nutrison Protein Plus) or with the MCT feed (Nutrison Peptisorb). If progressing well, oral intake will be introduced slowly from the third post-operative day. The investigators will measure the volume of fluid draining from the post-operative drain and analyse it in the lab to determine if there is a post-operative chyle leak. Should a chyle leak occur, it will be treated as per our usual protocol, which may include using alternative jejunostomy feeds, intravenous feeding (total parenteral nutrition), a procedure in radiology, or a repeat operation. All patients will be transitioned back to standard feeds for discharge.

Currently, unless contra-indicated (eg a feeding jejunostomy has not been placed), patients post MIO/RAMIO will commence percutaneous enteral feeds on the first post-operative day using a standardized enteral feeding formulation (Nutrison Protein Plus 1.25kcal/ml at 20ml/hr for 24 hours). This is then sequentially progressed until the patient is at their goal rate to meet their caloric and nutritional requirements. If there are no contraindications, PO intake commences on the 3rd post-operative day with restricted PO fluids, followed by progressive introduction of PO intake, as per our standard post-operative protocols.

Our hypothesis is, that by switching the enteral feed from standard feed to an MCT feed, this will reduce the production of chyle, allowing lymphatics to seal, and reduce the incidence of chylothorax post MIO/RAMIO.

This is a prospective randomized controlled trial. The sample size is 148 patients (72 each in intervention and control groups). The principal investigators (JB and WR) will be blinded to which feed patients are receiving. Due to the practicalities of administering jejunostomy feeds, the clinical dietetics service, nursing service and the non-consultant medical staff will not be blinded to the interventions. Due to the need to instigate training for home feeding, patients will not be blinded to the intervention.