Chyle leak (chylothorax) is a recognised complication following minimally invasive oesophagectomy for oesophageal cancer and may result in prolonged hospital stay, nutritional compromise, and need for additional interventions.

Medium-chain triglyceride (MCT) feeds reduce lymphatic flow as they are absorbed directly via the portal circulation rather than through the thoracic duct. While MCT feeds are commonly used in the management of established chyle leaks, their role in prevention has not been evaluated in a randomised controlled trial.

This single-centre randomised controlled trial will evaluate whether initiating postoperative jejunostomy feeding with MCT-based enteral nutrition reduces the incidence of clinically and biochemically confirmed chyle leak compared with standard enteral feeding in patients undergoing minimally invasive or robotic-assisted oesophagectomy.

Participants will be randomised in a 1:1 ratio to receive either MCT-based feeds or standard jejunostomy feeds starting on postoperative day 1. The primary outcome is the incidence of chylothorax. Secondary outcomes include chest drain output, re-intervention rates, and length of hospital stay.

Oesophagectomy is a key component of curative treatment for oesophageal cancer. Minimally invasive and robotic-assisted techniques are increasingly used and are associated with improved postoperative recovery. However, these approaches may be associated with a higher incidence of postoperative chyle leak due to extensive mediastinal lymphatic dissection.

Chylothorax occurs when the thoracic duct or its tributaries are disrupted, resulting in leakage of lymphatic fluid into the pleural cavity. This complication can lead to prolonged hospitalisation, nutritional depletion, immunosuppression, and may require radiological or surgical intervention.

Standard postoperative care includes initiation of jejunostomy feeding on postoperative day 1 using enteral formulations containing long-chain triglycerides. These lipids are absorbed via chylomicron formation and transported through the lymphatic system, potentially increasing thoracic duct flow and chyle production.

Medium-chain triglycerides (MCTs), in contrast, are absorbed directly into the portal venous system and bypass the lymphatic circulation. MCT-based feeds are widely used in the management of established chyle leaks, but their prophylactic use has not been evaluated in prospective randomised studies.

This study is a prospective, single-centre, randomised controlled trial conducted at Beaumont Hospital. Adult patients undergoing minimally invasive or robotic-assisted oesophagectomy with placement of a feeding jejunostomy will be eligible for inclusion.

Participants will be randomised in a 1:1 ratio to receive either:

• Standard jejunostomy feeding (Nutrison Protein Plus 1.25 kcal/ml), or
• MCT-based jejunostomy feeding (Nutrison Peptisorb 1 kcal/ml)

Enteral feeding will commence on postoperative day 1 and follow an identical escalation protocol in both groups.

The primary endpoint is the incidence of clinically and biochemically confirmed chylothorax, defined according to Esophageal Complications Consensus Group criteria.

Secondary endpoints include:

• Chest drain output volume
• Requirement for re-intervention (radiological or surgical)
• Postoperative length of stay
• 90-day postoperative morbidity

A total of 160 participants will be enrolled. Analysis will be conducted on an intention-to-treat basis.

Inclusion Criteria:

• Age ≥ 18 years
• Diagnosis of oesophageal cancer (adenocarcinoma or squamous cell carcinoma)
• Planned minimally invasive or robotic-assisted oesophagectomy (MIO or RAMIO) with curative intent
• Placement of feeding jejunostomy at or prior to oesophagectomy
• Able to provide written informed consent

Exclusion Criteria:

• Inability to provide informed consent
• No feeding jejunostomy placed at or prior to surgery
• Prior or concomitant malignancy that would interfere with study protocol or outcomes

The principal investigators responsible for outcome assessment will be blinded to feed allocation. Due to the practicalities of enteral feed administration and discharge planning, patients, dietetics staff, nursing teams, and non-consultant medical staff will not be blinded.