Microenteral nutrition is the practice of delivering small amounts of water, electrolytes, and readily absorbed nutrients (glucose, and functional amino acids) directly to the gastrointestinal tract. This has the advantage of keeping enterocytes alive and the gut immune barrier functioning, as well as increasing the tolerance for solid foods when they are introduced. In this way, patient recovery is optimised. In this short article, we take a look at some of the key areas of concern for veterinary professionals around early feeding:
Q “I fast my acute GI patients as they are vomiting and can’t handle food”
A Preservation of the gut immune barrier is essential for recovery but fasting will compromise this defence even further. Many sick GI patients will already have been anorexic for several days before presentation. Day 1 nutrition needs to be isotonic for rapid absorption, palatable to help overcome anorexia, and consist of simple, hypoallergenic micronutrients that are easily absorbed without the need for complex digestion. If the food is correctly balanced in this way, then only very small quantities are needed to keep the enterocytes alive, which most patients will tolerate.
In a study by Mohr in 2003, dogs with parvovirus benefitted from early enteral feeding which was shown to help maintain mucosal integrity, decreasing the risk of bacterial translocation. This led to faster clinical improvement in patients, significant weight gain, and decreased hospitalisation times. This study was pivotal in overturning the long-held belief that fasting was necessary, even in pets with vomiting and severe haemorrhagic enteritis.
“The old recommendations to keep a CPV patient NPO for 24-48 hours beyond the last instance of vomiting are no longer recommended.”
Q “Feeding small quantities won’t meet the resting energy needs of the patient”
A In the early stages of recovery your priority is to meet the patient’s simplest metabolic needs, whilst keeping the gut immune barrier functioning to prevent bacterial translocation. Microenteral nutrition is an ideal first step towards the reintroduction of calories needed for recovery and is well-tolerated, even in vomiting patients. Further calories can be introduced as part of a critical care feeding plan, based on assessment of patient needs. This can be achieved in the first instance by gradually increasing the amounts of the microenteral food which forms a safe bridge towards the feeding of an appropriate solid diet without overloading the gut.
Q “My patient has osmotic diarrhoea; feeding will only worsen this.”
A Classic advice for critically ill patients, particularly those with gastrointestinal dysfunction has been to rest (fast) the digestive tract for the first 24 up to 72 hours, with the aim of reducing the osmotic load and intestinal substrate for bacterial fermentation. However, the simple nutrients in microenteral nutrition (electrolytes, glucose and functional amino-acids) are easily and quickly absorbed, minimising the load for osmotic diarrhoea. Fasting the gut completely comprises the gut at a time when the metabolic needs are increasing, not decreasing.
Oralade® is supporting the Feed Don’t Fast campaign to help drive awareness of the need to feed patients proactively and early. Further information and a free CPD webinar on early enteral nutrition and gastrointestinal disease by Dr Ava Firth is available at www.feeddontfast.co.uk