A study of enteral tube feeding in critically ill patients

Introduction

For critically ill patients unable to eat, enteral tube feeding (ETF) is the preferred mode of feeding. The study aimed to investigate the amount of enteral feed obtained by patients on ICU in a busy London Teaching Hospital, the efficiency of initiation of feeding, and possible reasons for the failure of the above.

Methods

A prospective observational study was carried out over 1 month on patients admitted to a general and cardiothoracic ICU, who received ETF. Baseline data including age, reason for admission and illness severity score (SOFA) were documented. Length of time from admission to start of feeding was noted, and the volume of feed delivered to patients was recorded. The quantity of calories delivered to the patient was compared with the patient's ideal nutritional requirement (determined by the ICU ETF protocol). Feeding interruptions were also recorded.

Results

Fifty-two patients receiving ETF were observed for a total of 7,349 hours: 67.3% of patients were surgical and 32.7% medical. Patients received a median of 75% of their ideal calorific requirement. Feeding was started a median of 15 hours after admission, and a median of 5% of feeding time was interrupted after ETF had been started. Reasons for interruption included high gastric aspirates, starvation for procedures and displacement/blockage of feeding tube. The time to start ETF was significantly different according to admission categories (P = 0.033), with abdominal and cardiothoracic surgical patients having the greatest delays. Abdominal surgical patients also had a higher proportion of feeding interruptions due to high gastric aspirates and starvation for procedures. The SOFA score on day 1 significantly correlated with the time taken to start feeding (P = 0.008), length of total feeding interruption (P = 0.012), length of feeding interruption due to high gastric aspirates (P = 0.043), and length of feeding interruption due to starvation for procedures (P = 0.026).

Conclusion

The majority of patients received a high proportion of their ideal calorific requirement and began feeding within 24 hours. The data indicate that patients having had abdominal surgery or the sickest patients may be may be more likely to experience delays in initiation and interruptions to feeding