Greetings,
We did not host a nutrition support training program in June, because eventually we are forced in turn to spend some time away from work at the beach, forests and rivers 🙂 We still made time for journal club however, and this month is another article that investigated the influence of the amount of nutrition provided on patient outcome in the ICU.
June Citation:
Braunschweig CA, Sheean PM, Peterson SJ, et al. Intensive Nutrition in Acute Lung Injury: A Clinical Trial (INTACT). JPEN J Parenter Enteral Nutr. 2014 Apr 9. [Epub ahead of print]
Greetings,
We did not host a nutrition support training program in June, because eventually we are forced in turn to spend some time away from work at the beach, forests and rivers 🙂 We still made time for journal club however, and this month is another article that investigated the influence of the amount of nutrition provided on patient outcome in the ICU.
Summary of article:
This was a single-center, randomized, unblinded study (with concealed allocation into groups) of 78 patients from medical or surgical ICUs with acute lung injury comparing intensive medical nutrition therapy with standard nutrition support care. The intensive nutrition groups received EN feeding tubes and started EN quicker, used 24 hour infusions (no bolus or cyclic feeds), EN infusions were monitored daily, rates were increased after feeding interruptions occurred, and monitored to match energy goals. Following extubation, the intensive nutrition groups had oral intake initiated as soon as swallowing allowed and oral intake was encouraged by eliminating unnecessary therapeutic diets, assisting with feeding, and providing snacking options and meal tickets for cafeteria purchases.
Nutrition goals were based on 30 kcals, 1.5 gm protein per kg of admission weight, or adjusted weight (25% factor) if obese. Parenteral nutrition was started in both groups at 72-96 hours if EN was deemed not possible.
The primary outcome of the study was the occurrence of nosocomial infections. Secondary end points included days to weaning from mechanical ventilation, ICU and hospital LOS, and death. Interim safety analysis was planned every time 25 additional patients were added per group.
Inclusion and Exclusion Criteria:
Inclusion criteria:
Adult patients from the medical or surgical ICUs with a diagnosis of ALI, as defined by the American-European Consensus Conference.
Exclusion criteria:
Previously admitted to an ICU during the same hospitalization, had orders not to resuscitate, severe immunosuppression (eg, post–stem cell transplant, receiving chemotherapy), immobility or severe neurologic disease prior to admission.
Major Results:
There were 40 patients randomized to the intensive medical nutrition therapy (IMNT) group and 38 to the standard nutrition care group (SNC). After randomization, the groups were similar except that the baseline APACHE II score was significantly lower in the IMNT group.
Participants randomized to IMNT received significantly greater percentages of energy and protein goals (mean kcals: 88.7% IMNT vs 55.4% SNC) and significantly greater kcal/kg/d (mean 25.4 kcal/kg IMNT vs 16.6 kcal/kg SNC). There were no significant differences in PN, lipid emulsions, or propofol provision between the groups.
There was also no difference between groups in hospital or ICU LOS, duration of mechanical ventilation, number of infections, or number of days between hospital admission and study enrollment day. The average amount of insulin received over the entire study was not significantly different between groups, but when only the days and patients that received insulin were analyzed, the IMNT group received significantly more insulin than the SNC group.
The Data Safety Monitoring Board stopped the study early when it was revealed that significantly more deaths occurred in the IMNT compared with the SNSC group (16/40 [40%] vs 6/38 [16%], P = .017).
Author’s Conclusions:
“IMNT provided from ALI diagnosis to hospital discharge resulted in greater mortality compared with SNSC.”
Evaluation:
The strengths of this study include the fact that patients were randomized into groups with concealed allocation, there was close monitoring of all nutrition delivered, and accounting for all calorie sources.
Limitations our group found included the fact that this was a single center study that only enrolled a small number of patients. Notably, the APACHE II scores were significantly different at baseline, which suggests a breakdown of the randomization. The small size of this study means that there could be a significant difference in mortality between the groups due to chance. The study was (unavoidably) stopped early, which also introduces bias.
Our group also discussed the fact that 46% of the patients had a BMI > 30. The best available evidence is that obese critically ill patients appear to benefit from hypocaloric feedings, so it is a bit surprising that obese patients were included into a full feeding study. It will be interesting to see if the investigators further analysis identifies a difference in mortality based on BMI.
Even if we assume that the increased mortality in the IMNT group was not a chance occurrence, it is possible that providing full feedings alone may not be the only culprit. It is possible that measures to increase feeding rates after feedings are held essentially amounted to “temporary overfeeding”, and may have had negative effects, such as encouraging reflux, or contributing to glucose variability. Glucose variability is associated with worse outcomes, so rapid feeding rates after feedings were held could contribute to glucose variability.1 The authors did not provide details about how the “make up” feedings were administered for the IMNT group, such as the maximum allowed feeding rates.
One other aspect that we discussed was the choice of feeding formulas used. These were patients with acute lung injury, so it would be helpful to know if any patients received ARDS specific formulas
Our Take Home Message (s)
1. Intensive feeding protocols that attempt to meet full nutrition needs early in the admission in critically ill patients with ALI may increase mortality.
2. There is a need for large randomized studies of intensive feeding protocols on patient outcomes before adopting them in routine clinical practice.
Reference:
1. Meynaar IA, Eslami S, Abu-Hanna A, et al. Blood glucose amplitude variability as predictor for mortality in surgical and medical intensive care unit patients: a multicenter cohort study. J Crit Care. 2012;27(2):119-124.
Other News on the UVAHS GI Nutrition Website: (www.ginutrition.virginia.edu):
Upcoming Webinars 2014:
–Wednesday, June 25—Managing Absorption in the Adult Patient with Short Bowel Syndrome
–Fall webinars to be posted shortly
Check out What’s New:
–“Nutrition Support Blog”
–“ Resources for the Nutrition Support Clinician”
Latest Practical Gastroenterology article:
–Pogatschnik C. Trace Element Supplementation and Monitoring in the Adult Patient on Parenteral Nutrition. Practical Gastroenterology 2014;XXXVIII(5):27.
–Henry M. Nutrition Guidelines for Treatment of Children with Eosinophilic Esophagitis. Practical Gastroenterology 2014;XXXVIII(6):21.
Joe Krenitsky MS, RD
Carol Rees Parrish MS, RD
PS – Please feel free to forward on to friends and colleagues.