University of Virginia Nutrition
Well the dog days of summer are here...Our July trainees braved our record heat and traveled from Georgia, Vermont, Maryland and Tennessee. Those ice cold margaritas glasses of milk sure tasted good after work!
- Wu GH, Liu ZH, Wu ZH, et al. Perioperative artificial nutrition in malnourished gastrointestinal cancer patients. World J Gastro 2006;12(15):2441-2444.
This was a randomized, unblinded study of the effects of perioperative parenteral and/or enteral nutrition support in 512 moderately or severely malnourished patients with colorectal or gastric cancer. The perioperative nutrition group (N= 233) received 8-10 days of pre-operative nutrition and 7 plus days of post-operative nutrition (25 non-protein calories/kg + 1.5 gm protein/kg). The control group (N = 235 ) received oral intake pre-operatively and then hypocaloric post-operative nutrition (600 non-protein calories + 60gm protein/day) until gut function returned and then oral intake as tolerated. Those patients in the perioperative nutrition group deemed to have a "functioning" GI tract received enteral nutrition (EN) (n = 75, 32%), while the remainder received parenteral nutrition (PN) (n = 160, 68%). There were 44 patients dropped from the analysis in the postoperative period; 16 declined to continue the study, 28 patients were excluded due to unresectability of the malignancy.
Major Results reported by authors:
The authors reported a significant reduction in total complications (18.3% vs 33.5%, p = 0.012), septic complications (14.9% vs 27.9%, p = 0.011) and mortality (2.1% vs 6.0%, p= 0.003) in the perioperative nutrition group compared to the control group. There were no significant differences in infectious complications between the parenteral and enteral fed patients within the perioperative nutrition group.
The authors concluded that perioperative nutrition support is beneficial for moderately or severely malnourished GI cancer patients.
The strong points of this study are it's relatively large size, and the fact that it is a randomized study. One disadvantage is that it is not a double-blind study, which would, of course, be very difficult to achieve in a study like this. Another consideration is that the statistics were not completed in an intention-to-treat manner. Those patients that did not have a respectable process (n = 28) or who refused to continue (n = 16) were simply eliminated from the calculations; therefore the final statistics were not completed on a truly randomized population.
One other factor that must be taken into consideration is that the control group did receive post-operative parenteral nutrition support. The PN provided to the control group was hypocaloric, and short-term, but it can be argued that it served to increase the risk of infectious complications in the control group, but was inadequate to provide substantial nutritional benefit.
The group spent a little time discussing the lack of difference in complications between the enteral and parenteral fed patients in the perioperative-fed group. The authors point out the modest calorie goals of the PN group, and attention to glucose control as potential reasons for the lack of difference in complications between the EN and PN patients. In addition, we noted that the relatively small number of patients that received enteral nutrition (n = 75) and the uneven group sizes reduced the likelihood of detecting possible differences between the groups. It was also unclear why, if patients were allowed to eat orally, they required PN.
Take home message:
This is an interesting article that supports the use of perioperative nutrition support in moderately or severely malnourished surgical patients with GI malignancies. Further studies are necessary to determine if both pre- and post-operative nutrition is necessary in order to realize improvements in outcome. Future studies should include a control group that does not receive parenteral nutrition and is based on intention-to treat analysis.
Check out the latest Practical Gastroenterology article at:
Scroll down to GI Nutrition on the far left column and click on link
Then scroll down to box with links within the nutrition site
Nutrition Articles in Practical Gastroenterology is in the right column.
Madsen H, Frankel E H. The Hitchhiker's Guide to Parenteral Nutrition Management for Adult Patients. Practical Gastroenterology 2006:XXX(7):46.
Joe Krenitsky MS, RD
Carol Parrish RD, MS
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