The Feasibility and Benefits of Pre-operative Whey-protein Infused Carbohydrate Loading in Elderly With Hip Fractures Undergoing Surgery: a Pilot Study

INTRODUCTION AND BACKGROUND

Pre-operative carbohydrate loading is one of the many components of enhanced recovery after surgery (ERAS) protocol. It has been identified as one of the independent predictors among ERAS components to improve peri-operative well-being and reduce post-operative complications. While well-being is a subjective outcome, several surrogate outcomes have been used to quantify some of the aspects. These surrogate outcomes of well-being include post-operative nausea and vomiting, pain, and preservation of muscle strength.

Although the exact mechanism of how pre-operative carbohydrate loading improves these outcomes is unclear, there appears to be an anabolic effect by increasing insulin sensitivity, improving glucose control and reducing catabolism. Patients in anabolic state undergo less post-operative nitrogen and protein loss, which translates to preservation of muscle strength. Carbohydrate loading keeps the body in a fed state during the fasting period before surgery. This abolishes the starvation effects which causes reduced insulin sensitivity commonly seen with conventional fasting practice. This is an independent predictor which prolongs length of hospital stay, preservation of muscle mass and handgrip strength post-operatively.

While most studies have demonstrated benefits of carbohydrate loading in patients undergoing abdominal surgeries, the number of studies conducted in the orthopedic hip fracture population are limited. In addition, there may also be barriers to introducing a new protocol with carbohydrate loading to replace the existing conventional fasting practice. Studies showed diverse feasibility in terms of implementation, which seemed to be multifactorial. More studies are therefore required to identify the factors promoting or impeding such a practice in respective centres. Given that a significant number of the hip fracture population are malnourished elderly who may benefit from this intervention, the gap in literature in this population deserves a thorough attention.

The University Malaya Medical Centre is a tertiary hospital with an average of 200 hip fracture cases annually. To date, these cases are subjected to conventional fasting starting from midnight. They are usually fasted up to extended hours, putting them in a starved state before surgery. It is therefore the great interest of the current multidisciplinary teams involved in the clinical care of hip fracture patients to introduce carbohydrate loading as part of the fasting practice. This study aims to introduce the concept and assess the feasibility of such a practice. The results from this pilot study may be used to revolutionize the fasting practice in our hospital.