March 21, 2013
Severity Of Recovery Affected By Diet Before Surgery
Alan McStravick for redOrbit.com — Your Universe Online
Invasive surgery is, for the body, a particularly traumatic experience. However, for many, the greater trauma occurs during the recovery period immediately following a surgery. This is caused by inflammation of fat tissue, which is always negatively affected during a major surgery. Fat tissue is one of the most dominant components that make up the body.A new study, conducted by researchers at Brigham and Women´s Hospital (BWH) in Boston, takes a look at the last few meals a patient consumes before surgery and how adjusting those meals might make a difference in recovery after surgery.
The initial trauma caused by the surgery is responsible for directly affecting the chemical balance of fat tissue. Chemicals within the fat tissue are known to communicate with nearby and distant organs.
To conduct their study, the team utilized mouse subjects and found mice that consumed a typical Western, high-fat diet showed an exaggerated imbalanced response. To counteract this response, the researchers restricted food intake of the subject mice to a lower-fat diet a few weeks before a surgical procedure. They found this restriction worked to reduce the chemical imbalance to what could be typified as a more normal response. The results of their study are to be published in the April 2013 issue of the journal Surgery.
C. Keith Ozaki, MD, senior author and Director of BWH Vascular Surgery Research, and colleagues measured how fat responds to surgery and whether restricting caloric intake prior to a surgery might change how fat tissue responds to typical trauma associated with an operation.
"Surgeons have learned that generally minimizing trauma accelerates patient recovery from surgery," noted Ozaki. "While we do this well for specific organs such as the heart, blood vessels, liver, and so forth, we historically have paid little attention to the fat that we cut through to expose these organs. Our findings challenge us all to learn more about how fat responds to trauma, what factors impact this response, and how fat's response is linked to the outcome of individual patients."
One group of subject mice were fed a high-fat diet that consisted of 60 percent of caloric intake derived from fat. The control group was provided a diet that derived 10 percent of caloric intake from fat.
Three weeks before the scheduled surgeries, the team modified the diet of some of the mice in the high-fat group to a more normal diet. When performing the surgeries, the team utilized procedures typical in an operation. They observed the effect of the trauma and how it rapidly affected fat tissue at the surgery site and at points far removed. Conditions such as increased inflammation and decreased specialized fat hormone synthesis were observed. This was especially true in young adult mice and mice affected by a simulated wound infection.
The reduction of food intake before surgery, however, showed a reverse in these conditions for all mice, regardless of age and simulated infection. The team claims their results suggest that while fat is a very dominant tissue in the human body, its rapid malleability could be used to lessen complications in humans resultant from stressful situations like surgery.
James Mitchell, PhD, an assistant professor of Genetics and Complex Diseases at the Harvard School of Public Health, collaborated on the study. In his accompanying review article, he suggests restricting diet in humans prior to an operation would provide a unique opportunity to test whether this method could decrease the incidence and severity of surgical complications experienced as a result of increased tissue inflammation and other stressors.
Transferring the findings of the BWH study to human subjects may be a feasible, inexpensive and effective way of protecting the body from trauma experienced as a result of surgery. Mitchell´s review article specifically targets patients slated to undergo vascular surgery, as this population is at an increased risk of complications from surgery. If effective in humans, the BWH findings could limit occurrences of prolonged wound-healing problems, heart attack and stroke common to patients who have undergone this form of surgery.
"The relationship between surgical outcomes and obesity has always been complex," said Ozaki. "Our results and those of others highlight that the quality of your fat tissues appears to be important, along with the total amount of body fat when it comes to the body's response to an operation."
Funding support for the study was provided by the National Heart, Lung and Blood Institute of the National Institutes of Health, the American Heart Association, the Ellison Medical Foundation and the Glenn Foundation for Medical Research.