Predicting of enteral nutrition intolerance in critically ill patients

Abstract

Even in minimal morphological changes in the gut of critically ill patients, its ability to absorb nutrients, drugs and, in particular, acetaminophen is reduced. The search for a simple and accessible clinical method that allows to assess the possibility of enteral nutrition is rather actual. Objectives. To assess the prognostic value of the acetaminophen enteral absorption test in critically ill patients. Materials and methods. A single-center, prospective study was performed in 52 patients of the polyvalent intensive care unit (ICU). 0.5 g of paracetamol was injected into the nasogastric tube. After 10, 15, 20, 30, 40, 50 and 90 minutes 5 ml of venous blood was taken to determine the concentration of acetaminophen in it. On the next day the volume of administered and excreted via a nasogastric tube was recorded. Healthy volunteers (n = 12) were included in group 1. The second group (n = 15) - a positive balance by the nasogastric tube, the third group (n = 15) - the balance is negative up to 500 ml per day, the fourth - negative up to 1 liter per day, the fifth group - negative > 1 liter per day. To identify the predictive value and cutoff values of the test, the data were analyzed using the logistic regression method, and then the ROC analysis. The authors received permission from the local ethics committee. Results. The most informative time interval for determining the concentration of paracetamol in the blood after its administration into the stomach is the interval from 15 to 30 minutes. A strong correlation (r = 0.846 p < 0.001]) was found out between the results of the paracetamol test and the daily balance by the nasogastric tube. ROC analysis showed that the sensitivity of this test exceeds 86 %, and the specificity was about 75 %. If the concentration of paracetamol in the blood is > 6.17 |ig/ml successful total enteral nutrition is highly possible. The values of this indicator in the range from 2.47 |ig/ml to 6.17 |ig/ml can serve as the basis for the implementation of the method of partial enteral nutrition. We believe that at levels < 2.47 mcg/ml, a “minimal enteral nutrition” attempt can be made. Conclusion. The paracetamol absorption test in critically ill patients can be considered as an independent predictor of the feasibility of enteral zone feeding. Predicting enteral feeding intolerance using the paracetamol absorption test in critically ill patients can significantly improve the efficacy and safety of tube feeding method.