Refeeding Syndrome

To describe the incidence of hypophosphatemia in patients admitted to the ICU who have required mechanical ventilation. To analyze the presence of risk factors and its relationship with nutritional practice.

Prospective observational study.

Polyvalent ICUs of 2 University Hospitals.

Patients on invasive mechanical ventilation ≥72 h with normal level of phosphorus at admission.

None.

Electrolyte levels (phosphorus, magnesium, potassium) were determined on admission to the ICU and at 96 h. Risk categories on admission, caloric intake, insulin doses and acid-base status during the first 4 days of admission were recorded. Incidence was calculated as the number of patients who developed hypophosphataemia after admission. Univariate analysis was performed for between-group comparison and multivariate analysis of potential risk factors.

89 patients were included. The incidence of hypophosphataemia was 32.6%. In these patients phosphorus decreased from 3.57 ± 1.02 mmol/l to 1.87 ± 0.65 mmol/l (52.3%). The mean kcal/kg/24 h provided in the first 4 days was 17.4 ± 4.1, with no difference between the group that developed hypophosphataemia and the group that did not. Significant risk factors were insulin doses administered and pH and PaCO₂ values.

The incidence of hypophosphataemia at 96 h from admission in mechanically ventilated patients is high and unrelated to the risk category and hypocaloric nutritional practice used. Insulin dosis and acid-base status are the main determinants of its occurrence.

This study aims to investigate the potential correlation between the use of olanzapine, a psychopharmacological intervention commonly prescribed in Anorexia Nervosa treatment, and the occurrence of Refeeding Syndrome. Despite the acknowledged nutritional and biochemical impacts of olanzapine, the literature lacks information regarding its specific association with Refeeding Syndrome onset in individuals with Anorexia Nervosa. This is a naturalistic, retrospective, observational study, reporting the occurrence of Refeeding Syndrome in children and adolescents with Anorexia Nervosa, treated or untreated with olanzapine. Dosages and serum levels of olanzapine were assessed for potential associations with the occurrence of Refeeding Syndrome and specific variations in Refeeding Syndrome-related electrolytes. Overall, 113 patients were enrolled, including 46 (41%) who developed a Refeeding Syndrome. Mild (87%), moderate (6.5%), and severe (6.5%) Refeeding Syndrome was described, at a current average intake of 1378 ± 289 kcal/day (39 ± 7.7 kcal/kg/die), frequently associated with nasogastric tube (39%) or parenteral (2.2%) nutrition. Individuals receiving olanzapine experienced a more positive phosphorus balance than those who did not (F(1,110) = 4.835, p = 0.030), but no difference in the occurrence of Refeeding Syndrome was documented. The mean prescribed doses and serum concentrations of olanzapine were comparable between Refeeding Syndrome and no-Refeeding Syndrome patients.    Conclusion: The present paper describes the occurrence of Refeeding Syndrome and its association with olanzapine prescriptions in children and adolescents with Anorexia Nervosa. Olanzapine was associated with a more positive phosphorus balance, but not with a different occurrence of Refeeding Syndrome. Further, longitudinal studies are required. What is Known: • Refeeding Syndrome (RS) is a critical complication during refeeding in malnourished patients, marked by electrolyte (phosphorus, magnesium, potassium) imbalances. • Olanzapine, an atypical antipsychotic with nutritional and biochemical impacts, is used in Anorexia Nervosa (AN) treatment, however data concerning its association with RS are lacking. What is New: • The study observed RS in 46/113 (41%) young patients with AN. • Olanzapine-treated individuals showed a higher improvement in serum phosphate levels than untreated ones, although no impact on the occurrence of Refeeding Syndrome was observed.

Patients receiving parenteral nutrition (PN) may develop refeeding syndrome (RFS). This study determined RFS prevalence in hospitalized adults on PN and evaluated whether higher energy delivered by PN on day 1 of PN initiation was associated with RFS development.

We reviewed the medical records of adult patients receiving PN at a Thai quaternary hospital from June 2019 to May 2022. RFS was defined based on the Nutrition Management Clinical Practice Recommendation by the Society of Parenteral and Enteral Nutrition of Thailand. The association between PN energy delivery and RFS development was determined using a generalized estimating equation for multiple logistic regression analysis adjusted for NICE guideline risk factors.

A total of 547 patients was included (mean age 59.8 ± 17.2 years, mean body mass index 20.7 ± 4.8 ). The prevalence of RFS was 45%. Factors associated with RFS included energy from PN on the first day of PN initiation (adjusted odds ratio [aOR] 1.17; 95% CI 1.04-1.33; for every 5 kcal/kg/day increase), starvation >5 days prior to PN (aOR 1.54; 95% CI 1.04-2.26), concomitant diuretic use (aOR 1.81; 95% CI 1.25-2.64), low baseline potassium level (aOR 1.79; 95% CI 1.19-2.70), and individual compounding PN (aOR 1.61; 95% CI 1.04-2.51).

RFS was common among hospitalized patients receiving PN. The amount of energy delivered on the first day of PN was independently associated with RFS, raising a concern regarding initiation of PN with higher energy.