Reduced fasting in fast-track primary total knee arthroplasty: a randomized clinical trial

During the last decades fast-track surgery protocols have been implemented,
improving postoperative outcome and reducing hospital stay after Total Knee
Arthroplasty (TKA). One of the interventions of fast-track protocols is early
mobilization. This can be compromised by orthostatic intolerance due various
causes including fasting. Recently early postoperative consuming of an ice
popsicle reduced opioid and non-opioid requirements and improved well-being. We
presume that reducing the pre-operative fasting period will further optimize
postoperative rehabilitation.

Historically patients are instructed not to eat or drink after midnight before
surgery. This starvation period was maintained to prevent pulmonary aspiration
of gastric contents. The current literature have shown that reduced fasting
times are feasible, moreover 2 hours fasting for liquids and 6 hours fasting
for solid food before surgery is safe. Furthermore consuming a carbohydrate
drink 2-3 hours pre-operative was not associated with increased intake related
complications. To further optimize fast-track rehabilitation it is assumed that
reducing the preoperative fasting period is beneficial. Currently in the
Reinier de Graaf Groep patients are allowed to drink clear liquids till 2 hours
before surgery. Although the experience is that most patients maintain fasting
from midnight before surgery resulting in a preoperative fasting period of 8
hours or even more.

Fasting results in dehydration, hypoglycemia, electrolyte imbalance and
preoperative discomfort for the patient, which can be deceased by preoperative
intake of a carbohydrate drink. Both starvation and surgery cause insulin
resistance. Pre-operative carbohydrate drinks reduce the postoperative nausea,
vomiting and increase the well-being in non-orthopedic surgery.

Reduced insulin resistance by reducing the catabolic response can be achieved
by the intake of a carbohydrate drink pre-operatively. However most studies
were performed in non-orthopedic surgery and evidence of post-operative
benefits of a pre-operative carbohydrate drink is conflicting.
We presume that reducing the fasting period by adding a carbohydrate drink 2-3
hours prior to surgery is a good and feasible option to decrease orthostatic
intolerance and improve the pre- and postoperative well-being and thereby the
rehabilitation.

The objective of this study is to further improve the fast-track protocol, by
decreasing the fasting period through adding a carbohydrate drink 2-3 hours
pre-operative. This should improve well being and orthostatic hypotension which
can interfere early mobilization.

a randomized clinical trial.

The intervention group will receive a carbohydrate drink 2-3 hours prior to
surgery.

It is assumed patients will benefit from reduced fasting time preoperative as
well as postoperative.