University of Virginia Nutrition
Our October traineeship started out with rain, but by the end of the week we were enjoying superb Charlottesville Fall weather, with sunshine and highs in the 70’s and deliciously cool evenings. Our trainees hailed from Galveston Texas , Boise Idaho , and Hastings Nebraska .
- Villet S, Chiolero RL, Bollmann MD, Revelly JP, Cayeux R N MC, Delarue J, Berger MM. Negative impact of hypocaloric feeding and energy balance on clinical outcome in ICU patients. Clinical Nutrition 2005 Aug;24(4): page 502-509.
Study Question (s):
- The goal of this study was to assess the relationship between energy balance and outcome in critically ill patients.
- A prospective, observational study that utilized the data from 48 patients (out of 962 admissions) in a surgical ICU with a length of stay of at least 5 days. Data from 669 patient days were utilized. The feeding protocol of the intensive care unit was to begin early enteral feeding within 48 hours for malnourished patients and those with multiple injury or abdominal surgery for GI tumor. In all other patients, considered unlikely to tolerate oral intake within 5 days, the protocol was to reach goal feeding by day 4. Parenteral nutrition was used when EN was contraindicated or “when difficult EN causes obvious energy deficit.”
- Energy goals were set at 1.3 X REE (indirect calorimetry) or at 30 kcal/kg when indirect calorimetry was not possible. Energy balance (calories delivered – energy needs) was calculated daily, and calculated as weekly deficit and cumulative balance.
The authors reported that the average calorie deficit was 1270 calories/day in the first week, and 625 calories/day in week 2. Mean time to begin feedings was 3.1 days (+/- 2.2 days), and there were a total of 101 patient days (15%) without feeding. Five patients were classified as malnourished; 18 patients were identified as meeting criteria for early enteral feeding. However, only 11 patients actually received early feeding. Seventy-five percent (n = 36) of patients received only EN, 23% (n = 11) received TPN + EN, and 2% (n =1) received only TPN.
The cumulative calorie deficit was significantly associated with ICU length of stay (p<0.001). The calorie deficit for the first 7 days, as well as the total calorie deficit was significantly associated with both total and infectious complications. Calorie deficit was not associated with mortality. Plasma proteins (albumin and prealbumin) did not correlate with nutrition delivery, but were inversely related to the inflammatory status.
A negative calorie balance correlated with increasing number of complications, particularly infections. Delayed initiation of nutrition support produces energy deficits that are not compensated for later. The total nutrition deficit may be a useful indicator of nutrition status, but requires further testing.
Intuitively, the concept of calorie deficit “makes sense” – if you are fed inadequately for long enough you become malnourished, and (perhaps) share the poor outcome that has been associated with malnutrition in other populations. However, this is NOT a randomized study – it is observational, and therefore can describe only associations, and as a result, it is not possible to make cause-and-effect conclusions. There is no way to control for all the factors relating to severity of illness without randomizing two large groups. The concern is that it may not be the calorie deficit itself that determines the outcome; it may just be that patients with poor outcome are sicker, and therefore receive less nutrition, whether by GI intolerance, or that they require more procedures, test, lines, codes, etc.
That said, the concept of calorie deficit might have validity. The problem is that we just have no way of knowing if, or when, this becomes a significant issue. Some observational studies have reported that there were no significant differences between critically ill patients who received full nutrition and those who received only 50% of nutrition goals, and other studies have reported improved outcomes in the groups who received less calories.
Take home message:
- The concept of calorie deficit is an interesting one, but this study only points to the need for double-blind trials (with adequate numbers of both malnourished and well-nourished patients) comprised of early, full nutrition versus delayed, partial, or no nutrition.
- This is additional evidence that prealbumin and albumin have nothing to do with the amount of nutrition you provide to critically ill patients.
1) The Virginia chapter of ASPEN (VASPEN) has their annual conference on November 4th and 5th in Fredricksburg, VA. We have a great program and excellent speakers planned. Speakers include Ken Kudsk, Mark DeLegge, Gary Zaloga, Charlene Compher, and our topics include, pancreatitis, gastroparesis, critical illness, antioxidants, perioperative nutrition support, and much, much more. If you are interested in joining us for a fun conference check out this link for more information and a registration form. http://www.nutritioncare.org/events/VA_1105.pdf
2) Check out the latest Practical Gastroenterology article: (Get ready to laugh – it’s a hoot!)
- Saalwachter Schulman A, Sawyer RG. Have You Passed Gas Yet? Time For A New Approach To Feeding Patients Postoperatively. Practical Gastroenterology 2005;XXIX(10):82.
To Access the GI Nutrition Page at UVAHS, go to:
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 left column.
3) We have added the picture gallery to the traineeship website. http://www.healthsystem.virginia.edudh/traineeship.html. Look at the right side, and you should see “Photo Gallery (new!!).” We would like to make a photo gallery of all past trainees. If you are interested, please send us a digital photo and we will add you to the gallery with your name and “class.”
Joe Krenitsky MS, RD
Carol Parrish RD, MS
PS – Please feel free to forward this on to friends and colleagues.