Endocrine Effects of Arginine-Vasopressin After Pediatric Cardiac Surgery.

Arginine-vasopressin (AVP) stimulates adrenocorticotropic hormone (ACTH) secretion and may contribute to the stress response after surgery. Its endocrine effects in children undergoing congenital heart surgery remain unclear. We prospectively evaluated 49 children (median age 8 months, IQR 5-59 months; median weight 11.0 kg, IQR 7.2-26.3 kg) after corrective cardiac surgery with cardiopulmonary bypass. Patients receiving AVP within 48 h postoperatively (n = 23) were compared with those not treated (n = 26). Baseline hormone levels (AVP, ACTH, cortisol, cortisol-binding globulin) were measured. Serial cortisol, ACTH, sodium, and glucose levels were analyzed. Time-series linear regression models examined associations between AVP therapy and adjusting for covariates such as cortisol, ACTH, CBG, and AVP levels. Baseline did not differ between groups. AVP therapy was not associated with significant differences in ACTH or cortisol over time. A non-significant trend toward higher cortisol was observed in AVP-treated patients. Regression analyses demonstrated significant associations between ACTH and cortisol (coefficient = 0.0325, p < 0.01), cortisol and systolic blood pressure (coefficient = 0.005, p < 0.01), and baseline AVP level with systolic blood pressure (coefficient = 0.003, p < 0.01) and renal oxygen extraction ratio (coefficient = 0.124, p = 0.01) and hormone levels. In this prospective cohort of children after congenital heart surgery, AVP therapy did not significantly alter ACTH or cortisol levels. Cortisol and baseline AVP levels were independently associated with hemodynamic markers. These findings suggest that the hemodynamic benefit of AVP is unlikely to be mediated through hypothalamic-pituitary-adrenal axis activation. Larger studies are needed to confirm these results.