Postoperative Electrical Muscle Stimulation Two

A Three-Arm Randomised Controlled Trial to Establish Effectiveness of NMES With or Without Protein Supplementation to Preserve Muscle Mass and Strength and Improve Functional Outcomes After Abdominal Surgery for GI Cancer

Undesirable loss of skeletal muscle mass (atrophy) is a common feature of many diseases as well as ageing, bed rest and physical inactivity. Losing muscle can lead to a reduction in one's ability to perform physical activities, and reduce independence and overall health. Muscle mass loss occurs very quickly (i.e., within a few days) after surgery.

The investigators previous work has shown that neuromuscular electrical stimulation (NMES) of the thigh muscles on one side of the body can help maintain muscle mass and strength on the stimulated side after surgery. Since then, additional work has been carried out to find the most effective form of stimulation to build muscle.

The current study aims to use this refined stimulation protocol in a clinical trial on the wards after major abdominal surgery. The intervention will involve delivering stimulation to both thighs in the few days after surgery, so that the investigators can assess whether this stimulation can preserve muscle mass and strength, and also, patients' ability to perform physical activities after surgery. In addition, the study will aim to find out whether any benefit provided by electrical stimulation can be increased further by taking a protein supplement at the same time.

The main objective of this trial is to assess whether neuromuscular stimulation (NMES) can minimise muscle loss following abdominal surgery for cancer; and whether such effect is further improved by simultaneous protein supplementation.

The main questions it aims to answer are:

• Does NMES training reduce the volume of muscle lost from the vastus lateralis (VL) muscle (in the thigh) after surgery as measured on ultrasound scan 5 days after surgery?
• Does NMES training together with protein supplementation lead to greater reduction of VL muscle volume loss on ultrasound 5 days after surgery then NMES alone?

Researchers will allocate participants into three groups (using a randomisation software).

All participants will visit the hospital once before surgery for starting point measurements including ultrasound.

Whilst they are in hospital, from the first until the fourth day after surgery, they will have the following interventions:

• Group 1 (the control group) will receive usual post-operative care with no additional interventions;
• Group 2 will receive normal postoperative care and twice daily NMES training sessions and a flavoured (placebo) drink
• Group 3 will receive normal post operative care as well as twice daily NMES training sessions and two protein rich drinks per day.

On the fifth day after surgery all participants will have repeat measurements including ultrasound to assess the extent of muscle loss they had since surgery.

Inclusion Criteria:

• Adult patients (age 18 or over at the time of diagnosis made at MDT (multi-disciplinary team meeting)
• MDT outcome of colorectal or gastric cancer or non-invasive neoplasia (tissue-proven, or radiologically diagnosed and clinically suspected) with the intention to treat with curative abdominal surgery
• Agreed management plan for open or minimally invasive (laparoscopic or robot assisted) segmental abdominal (colonic or gastric) resection at the Royal Derby Hospital
• Sufficient mobility and fitness to complete normal ERAS (enhanced recovery after surgery) protocols following surgery
• Basic conversational spoken English language
• Ability to give informed consent

Exclusion Criteria:

• Upper GI (gastrointestinal) cancer requiring thoracotomy/thoracoscopy
• Pre-existing neuromuscular disease (including Parkinsons disease)
• Pacemaker, implantable cardiac defibrillator or other implanted nerve stimulator device
• Metal prostheses or other metal-work in either upper legs (hip/knee/femur)
• Dementia or other cognitive problem or language barrier causing an inability to follow instructions and operate NMES machine
• Inability to give informed consent
• Disability preventing completion of ERAS after surgery (requiring Zimmer frame/wheeled frame/wheelchair to mobilise or bed-bound)
• Peripheral vascular disease
• Epilepsy
• Pre-existing diagnosis of chronic kidney disease or estimated glomerular filtration rate <60 on screening visit
• Pre-existing diagnosis of liver disease
• Intubation or intensive care admission during study period (between day 0-5 post-op); (surgical high dependency unit patients will be included)
• Return to theatre for surgical complication within first 5-days post operation
• History of rhabdomyolysis
• Pregnancy
• Deep vein thrombosis within past 6-months
• Allergy to whey protein
• Patient refusal of whey protein products on grounds of dietary requirements or intolerance
• Participating in another clinical trial concurrently or within the last 6 months
• Known infection with blood borne virus