Our aim is to determine the prevalence of vitamin D deficiency in children with congenital heart disease (CHD). In addition, we demonstrated the effect of cardiopulmonary bypass (CPB) on vitamin D, parathyroid hormone (PTH), and calcium levels. The association between perioperative vitamin D levels and postoperative clinical outcomes has been explored. A prospective observational study was conducted from February 2018 to June 2019 on 69 children undergoing elective surgery for CHD under CPB. Blood samples were collected preoperatively, immediate postoperatively, and 24 h postoperatively. Vitamin D deficiency was present in 34 (49.3%) patients preoperatively and 63 (91.3%) patients immediately postoperative. We identified 42.03% decline of 25(OH)D immediately postoperative. Changes in ionized calcium (iCa) concentrations were accompanied by reciprocal alterations in PTH concentrations. Lower postoperative 25(OH)D was associated with higher maximum vasoactive inotropic score (VIS) in the first 24 h postoperative (r = - 0.259, p = 0.03).Conclusion: Vitamin D deficiency is common in children with CHD and the majority are vitamin D deficient following cardiac surgery with acute decline of serum 25(OH)D after CPB. Lower postoperative vitamin D levels in children undergoing cardiac surgery are associated with the need for increasing the inotropic support.What is Known:• Vitamin D is a pleiotropic hormone, important for calcium homeostasis.• Vitamin D deficiency might affect the outcome in critically ill patients.What is New:• Cardiopulmonary bypass causes acute decline of vitamin D in children.• Lower postoperative vitamin D is associated with higher inotropic support.
Keywords: Cardiopulmonary bypass; Congenital heart disease; Parathyroid hormone; Pediatric cardiac surgery; Vitamin D deficiency.