Formulation and Administration of Enteral Feeds

Abstract

Enteral feeding (EF) is used mainly for patients with oral failure due to neurological or head/neck problems. If the gut is functional, it is the first line of treatment for clinically administered nutrition and hydration (CANH), also referred to as artificially administered nutrition and hydration (AANH). Enteral nutrition (EN) and/or parenteral nutrition (PN) are both equally efficacious methods of nutrition support, if prescribed and used appropriately.

There are three main formula types of EF, namely, standard (whole protein), peptide (semi-elemental) and specialized formulas, provided as oral/sip feeds or tube feeds. Most EFs are now sterile liquid ready-to-use feeds that should be light, and heat protected during preparation and administration to avoid instability and loss of certain nutrients. Absorption of nutrients can also be adversely affected or enhanced by nutrient-nutrient interactions or protein deficiency.

When enterally feeding a patient it is important to assess the absorption of the feed (increasing or maintaining weight/muscle mass, in the absence of oedema, no diarrhoea or aspirates/other losses) and the clinician must be aware that EN may make a patient more unwell in some circumstances, for example a small perforation of the intestine (often undetected for days/weeks) or due to exacerbating the underlying condition (e.g. mesenteric ischaemia or occasionally pancreatitis). These conditions may be suspected if the inflammatory markers are abnormal (e.g. raised C-reactive protein (CRP) or platelets and a low albumin), or there is no weight/muscle gain (in the absence of oedema) with adequate nutritional support.

Administration of medications via EF tubes is increasingly popular but care is necessary to avoid drug-nutrient interactions (DNI). Published guidelines for early and hypocaloric feeding, ET flushing and maintenance are now available. Quality assurance procedures that are necessary for the prescribing, preparation, administration, and monitoring of EN and any concurrent medication therapy, should be managed by a multidisciplinary nutrition support team (NST).