Definition, prevalence, and outcome of feeding intolerance in intensive care: a systematic review and meta-analysis

Abstract

Clinicians and researchers frequently use the phrase 'feeding intolerance' (FI) as a descriptive term in enterally fed critically ill patients. We aimed to: (1) determine what is the most accepted definition of FI; (2) estimate the prevalence of FI; and (3) evaluate whether FI is associated with important outcomes. Systematic searches of peer-reviewed publications using PubMed, MEDLINE, and Web of Science were performed with studies reporting FI extracted. We identified 72 studies defining FI. In 33 studies, the definition was based on large gastric residual volumes (GRVs) together with other gastrointestinal symptoms, while 30 studies relied solely on large GRVs, six studies used inadequate delivery of enteral nutrition (EN) as a threshold, and three studies gastrointestinal symptoms without reference to GRV. The median volume used to define a 'large' GRV was 250 ml (ranges from 75 to 500 ml). The pooled proportion (n = 31 studies) of FI was 38.3% (95% CI 30.7-46.2). Five studies reported outcomes, all of them observed adverse outcome in FI patients. In three studies, respectively, FI was associated with increased mortality and ICU length-of-stay. In summary, FI is inconsistently defined but appears to occur frequently. There are preliminary data indicating that FI is associated with adverse outcomes. A standard definition of FI is required to determine the accuracy of these preliminary data.

A review of feeding intolerance in critically ill children

“…Two studies defined feeding intolerance as the number of stools per 24 h period and/or the presence of vomiting or abdominal pain and/or tenderness [10,19]. Similarly, an adult systematic review of 72 intensive care studies [2] found that 43 different definitions of feeding intolerance were used, with GRV used in 88% of these alone or in combination with other signs.…”

“…The databases CINAHL plus, EBSCOhost, and Medline were searched in January 2018 using the term/s Bfeeding intolerance^and Btoleranceâ nd Bchild^or Bpediatric.^We also replicated the search strategy of the systematic review of feeding intolerance in adult intensive care [2]. Inclusion criteria were papers published in English or French and related to critically ill children (aged term to 17 years) without a limit applied to search years.…”

Comparison of different definitions of feeding intolerance: A retrospective observational study

“…Observational data are consistent with the concept that GI dysfunction is clinically important, but the absence of an agreed definition of FI limits generalizability of research undertaken in this area [7]. The most frequently used definition of FI is as based on aspiration of the gastric residual volume (GRV) during enteral feeding, but the threshold volume chosen varies considerably between studies and investigators [8]. Other investigators have focused on the inability to reach a threshold amount of energy that is administered to a patient [9,10].…”

Prevention of Aspiration in Adults

“…13 Feeding intolerance was primarily based on large gastric residual volumes (GRVs) together with other gastrointestinal symptoms. Disease severity has an impact on GRVs.…”