Prevention of Vitamin D Deficiency Following Pediatric CHD Surgery: a Phase II Dose Evaluation Randomized Controlled Trial Comparing Usual Care With a High Dose Pre-operative Supplementation Regimen Based on the Institute of Medicine Daily Upper Tolerable Intake Level

Our research group has shown that almost all children with congenital heart disease (CHD) are vitamin D deficient following heart surgery. This work strongly suggests that the vitamin D intake presently recommended for healthy children, and also given to children with CHD, is inadequate to prevent vitamin D deficiency following surgery. Unfortunately, there have been no studies investigating any other vitamin D dose in children with heart disease. Recently, a higher dose of vitamin D intake has been approved (by the Institute of Medicine and Health Canada) and recent work on healthy children has shown it to be safe. The objective of this study is to determine whether this recently approved higher dose of vitamin D can safely reduce the number of children who are vitamin D deficient following surgery. This dose evaluation study will also evaluate whether it is possible to perform a large study (across Canada) to determine whether vitamin D supplementation can improve outcomes following surgery. It is hypothesized that a daily high dose vitamin D regimen, modeled on the Institute of Medicine daily upper tolerable intake level (UL), will significantly reduce vitamin D deficiency following CHD surgery, when compared with usual intake.