Evaluation of Calcium Homeostasis and Dietary Supplementation for Pediatric and Neonatal Patients Receiving Extracorporeal Membrane Oxygenation Support.

Objectives: Although the use of extracorporeal membrane oxygenation (ECMO) significantly improves survival in patients with persistent respiratory or cardiovascular failure, it also induces physiologic stress and disrupts homeostatic mechanisms. Patients undergoing ECMO support at our institution have required widely variable quantities of calcium supplementation for maintenance of normal calcium levels. Our primary objective was to assess the frequency of calcium abnormalities in pediatric and neonatal ECMO patients. Secondary objectives included quantifying electrolyte supplementation provided during ECMO and determining the relationships between calcium abnormalities and ECMO duration, mortality, and intensive care and hospital length of stay.

Methods: We performed a single-center retrospective chart review of all patients less than 18 years of age who received ECMO support between July 1, 2013, and May 31, 2016. Clinical and laboratory data were reviewed for each patient for the duration of ECMO support, and the incidence of ionized calcium outside the reference range of 1.1 to 1.4 mmol/L beyond the first 24 hours of ECMO was recorded.

Results: Seventy-eight patients were included in the study: 51 patients (65%) experienced at least one reading outside the normal ionized calcium range, while 27 patients (35%) were normocalcemic during their ECMO course. There were no differences between groups in the quantities of calcium, phosphate, or vitamin D administered during ECMO. Abnormal calcium levels were associated with a longer duration of ECMO (median 9 days vs 6 days, p = 0.0054), prolonged ICU length of stay (median 33 vs 18 days, p = 0.0055), and prolonged hospital length of stay (median 52 vs 40 days, p = 0.0239). No significant differences were found in survival to decannulation or survival to hospital discharge.

Conclusions: Calcium abnormalities occur frequently in pediatric and neonatal patients during ECMO and are associated with worse patient outcomes. The underlying physiology of these changes is thought to be related to ECMO-induced disruption of normal calcium homeostasis.