Reuters Health Information (2013-07-12): Low-calorie diet before liver surgery may reduce blood loss
Low-calorie diet before liver surgery may reduce blood loss
Last Updated: 2013-07-12 18:37:23 -0400 (Reuters Health)
NEW YORK (Reuters Health) - Restricting patients to a low-calorie diet for the week before hepatic resection reduces the amount of fat in the liver and blood loss during the procedure, a retrospective study suggests.
Researchers looked for signs of steatosis and steatohepatitis in tissue taken from patients' livers, both of which have been associated with worse outcomes and death following surgery. It included 111 patients, more than 90% of whom were having surgery for cancer.
The study, published June 27 in Surgery, wasn't rigorously designed: the first 60 patients were not given any preoperative dietary restrictions, while the final 51 were given dietary instructions comprised of meal options providing 900 kcal/day, primarily fats and carbohydrates. When asked on the day of surgery, all of the patients in the restricted diet group said they adhered to the instructions.
The groups were generally well-balanced, although the control group had a significantly higher rate of diabetes and the diet-restricted group had a higher rate of preoperative chemotherapy treatment. Mean body mass was 27.2, and was similar in the two groups; 32% overall had a body mass index of 30 or more.
A gastrointestinal pathologist blinded to the origin of the samples found that compared to patients who ate normally before their operations, those who followed the diet had significantly less steatosis (15.7% vs 25.5% of hepatocytes containing fat, p=0.05) and less steatohepatitis (15% vs 27%, p=0.02).
Patients who dieted also had a lower mean intraoperative blood loss (600 vs 906 mL, p=.002).
The study was done by surgeons at Dartmouth-Hitchcock Medical
Center, who took the diet from the bariatric surgery group at their institution. All patients undergoing laparoscopic gastric bypass at that hospital submit to a two-week pre-operative diet.
Two major limitations of the study were that it was non-randomized and that compliance with the diet in the experimental arm was self-reported by patients. But the investigators, led by Dr. Richard Barth, think it's unlikely that factors other than diet affected the results because univariate and multivariate analyses each showed that diet and BMI were associated with lower rates of steatosis, and BMI was similar in both groups.
"This intervention is easily instituted, so it is clinically feasible," the authors said, adding that "many studies" by other groups have shown that patients with less steatosis have fewer perioperative complications and fewer infections complications after liver resection.
The authors did not respond to a request for comment.