Failure to Thrive Consider Refeeding Syndrome

Clinical Question 3: What patients are considered at risk for RFS?

FTT Team Recommendation:

The FTT Team RECOMMEND based on very low quality evidence consideration of refeeding syndrome in a patient with FTT who has an ideal body weight less than 70% and/or a patient is felt to be utilizing fat or protein as their energy source secondary to starvation.

Literature supporting this recommendation:

No randomized controlled trials, cohort or case controlled studies exist in the adult or pediatric literature on RFS. Available literature includes case reports, expert opinion and institutional protocols (Afzal et al., 2002; Boateng, et al., 2010; Dunn, Stettler, & Mascarenhas, 2003; Fuentebella & Kerner, 2009; Gariballa, 2008; Khan, Ahmed, Khan, & Macfie, 2011; Marinella, 2003; Mehanna, Moledina, & Travis, 2008; Tresley & Sheean, 2008; Worley, Claerhout, & Combs, 1998). Pathophysiology of RFS is well described. Patients in a state of starvation, acute or chronic, are ultimately utilizing fats and protein as their energy source. This results in a loss of body fat and protein with subsequent depletion of electrolytes including potassium, phosphorus and magnesium. Reintroduction of nutrition leads to a rapid increase in serum insulin as glucose becomes the preferred energy source. With insulin surges, extracellular potassium, phosphorus and magnesium move intracellular. These ion concentration shifts can lead to multisystem dysfunction and risk of life threatening cardiovascular effects. 

No consensus exists on the definition of RFS, criteria for diagnosing RFS or guidelines to identify high risk pediatric patients. Adult opinion suggests that patients at risk for RFS include: oncology patients, alcoholics, stroke patients, inflammatory bowel disease, AIDS/HIV, chronic pancreatitis and severe malnutrition (marasmus/kwashiorkor) (Khan, et al., 2011). Pediatric patients felt to be at highest risk include patients with a >10% weight loss within 2-3 months or patients at or below 70% ideal body weight (American Society for Parenteral and Enteral Nutrition, 2010; Tresley& Sheean, 2008).

Extrapolation of at risk patients to the classic FTT infant less than 2 years old needs to be determined on a case by case basis. Case reports in pediatric patients focus on adolescent patients with eating disorders, severe IBD or significantly malnourished oncology patients. Development of RFS in these patients was after immediate reintroduction of complete nutrition either via parenteral routes or oral feeds greater than or at 100% estimated energy requirement (EER). No case reports exist of RFS in patients less than 1 year of age with FTT that was being evaluated for organic versus non-organic disease with the exception of the intentionally starved neonate.

Clinical Question 4: What frequency of labs should be obtained in a patient at risk for RFS?

FTT Team Recommendation:

The FTT Team RECOMMEND based on very low quality evidence consideration for obtaining BMP, magnesium and phosphorus levels for a patient felt to be at risk for RFS that will require TPN, NG feeds or is consuming over 100% EER after a period of starvation or utilization of fat and protein as their energy source.

Literature supporting this recommendation:

There are multiple strategies published in the literature on how to manage patients with RFS. Most cite identification and prevention as keys to management and argue for a 'start low and go slow' strategy to reintroduction of adequate calories and nutrition. While multiple authors, including A.S.P.E.N., stress the importance of electrolyte monitoring up to four times daily and as long as two weeks for patients with RFS; no authors identify lab recommendations to diagnose RFS (Adkins, 2009; Afzal, et al., 2002; Mehanna, et al., 2008). If a patient is felt to be at risk for RFS, we recommend obtaining a BMP, magnesium and phosphorus levels and replacing electrolytes as needed. Subsequent lab frequency can then be determined at the discretion of the provider noting that RFS can occur at a range of 0.5 to 21 days after introduction of nutrition with a median of 3 days (Boateng, et al., 2010). In patients felt to be at the highest risk, or patients not controlling their own caloric intake such as patients fed NG or requiring TPN, we recommended starting feeds at less than 100% EER with close monitoring of advancement until goal feeds are met. Anecdotal evidence at CMH has found that children that were acutely starved and subsequently reefed with >100% EER seemed to develop RFS or electrolyte abnormalities.

These guidelines do not establish a standard of care to be followed in every case. It is recognized that each case is different and those individuals involved in providing health care are expected to use their judgment in determining what is in the best interests of the patient based on the circumstances existing at the time. It is impossible to anticipate all possible situations that may exist and to prepare guidelines for each. Accordingly these guidelines should guide care with the understanding that departures from them may be required at times.

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