Introduction
Methods
Results
The pathophysiology of feeding intolerance in critically ill children
Definitions of feeding intolerance in critically ill patients found in the literature search
Study | Study type | Objective of study | Definition of feed intolerance |
---|---|---|---|
Mayer et al. 2002 [22] | Prospective interventional study | Amylin associated with delayed gastric emptying in children | GRV > 125% 4 h following a feed challenge |
Lyons et al. 2002 [19] | RCT | Continuing vs withholding transpyloric feeding during weaning and extubation | Abdominal distention and pain or tenderness |
Horn and Chamboyer 2003 [10] | RCT | Continuous versus intermittent bolus feeding | No. of stools per 24 h and prevalence of diarrhea and vomiting |
Sanchez et al. 2007 [33] | Prospective observational | The tolerance of early transpyloric feeding in critically ill children | Significant abdominal distention with clinical alteration or increase in intra-abdominal pressure, GRV > 50% of the volume administered in the previous 4 h, severe diarrhea (> 5 loose stools a day) or severe NEC |
Sanchez et al. 2007 [34] | Prospective observational | The tolerance of early transpyloric feeding in critically ill children after heart surgery | GRV > 50% of the volume administered in the previous 4 h |
Willis et al. 2008 [48] | Prospective observational | The safety of feeding neonates on prostaglandin | GRV > 2/3 of prior feed or bilious vomiting or an increase in abdominal girth of >3 cm over an 8 h period or occult blood in stools or x-ray indicating signs of NEC |
Van Waardenburg et al. 2009 [45] | RCT | Early protein and energy in critically ill children | GRV > 50% of the administered feed volume over the previous 4 h on more than one occasion, occurrence of any gastric distention and vomiting and/or diarrhea defined as > 4 stools per day of watery consistency and leading to substantial fluid loss as negative fluid balance or by hemodynamic consequences |
Simackachorn et al. 2011 [35] | RCT | Effect of EN supplemented with pre- and probiotics on fecal microflora | Abdominal distention, episodes of vomiting and diarrhea and GRV (> 50% of the previously administered volume) |
Brown et al. 2012 [5] | Before and after study | To test the impact of a feeding protocol | Emesis, elevated GRV × 2, or elevated GRV × 1 and abdominal girth increase |
Panchal et al. 2014 [28] | Retrospective observational | Transpyloric feeding in shocked children | Used a preterm definition: GRV > 2 ml/kg or ½ the amount fed over the prior 3 h, a change in the color of the aspirate top green or red, abdominal distention with tenderness or a change in stool consistency to brown or red |
Hamilton et al. 2014 [9] | Before and after study | Testing of a new feeding protocol | GRV > 3 ml/kg or evidence of EN intolerance after 4 h of feeding |
Yoshimuru et al. 2015 [50] | Before and after study | Testing of a new feeding protocol | GRV > half of the quartering dose after 2 h of feed delivery |
Somnez-Duzkaya et al. 2016 [37] | RCT | Continuous post pyloric vs intermittent gastric feeding on VAP | GRV greater than 2/3 of the last feed in intermittent gastric bolus feeding |
Fayazi et al. 2016 [7] | RCT | Continuous versus intermittent feeding | GRV > 100 ml after 4 h of feeding by either method |
Martinez et al. 2017 [21] | Prospective observational | To assess delayed GE in critically ill children > 12 months of age | GRV > 3ml/kg or > 150 ml or if one of the following were recorded in a 24-h period: 2 or more episodes of emesis, bilious or non-bilious; 3 or more episodes of loose stool; abdominal distention defined as 2 or more increases in abdominal girth or subjective abdominal discomfort |
Signs and symptoms used to define feeding intolerance in critically ill children
Gastric residual volume
Vomiting
Bowel sounds and the frequency of bowel movements
Abdominal pain and/or distention
Markers of systematic tissue perfusion
Sign/symptom | Comment |
---|---|
Gastric residual volume (GRV) Colour of gastric aspirate | Most commonly used parameter, invalid marker of delayed gastric emptying, definitions highly variable and no evidence to support “high” GRV and prone to measurement error Very subjective |
Vomiting (emesis) | May be induced by coughing, opiates and other drugs, withdrawal syndrome |
Diarrhea | Definition problematic in infants and can be induced by infections, drugs, bowel ischemia, withdrawal syndrome |
Stool output | May be useful if being fed enterally |
Abdominal distention | Subjective unless girth measured accurately over time and may be induced by other factors; no clear threshold |
Bowel sounds | No evidence relates to feed tolerance, are objective, but often poorly assessed |
Raised serum lactate | Used commonly, different thresholds of tolerance used [Tume et al. 2017; Valla et al. 2015] |
Splanchnic NIRS (near-infrared spectroscopy) | No research in critically ill children in relation to feed tolerance |