Peri-operative Assessment of the Hypothalamic-Pituitary-Adrenal Axis Predicts Outcome in Neonates Undergoing Cardiac Surgery
This is a prospective observational study. The purpose is to investigate the incidence of HPa axis immaturity or dysfunction in neonates undergoing heart surgery and to examine the relation between HPa axis dysfunction and postoperative hemodynamic instability. Late preterm and term neonates with CHD admitted for cardiac surgery will be enrolled after parental consent. Preoperatively HPa axis immaturity or dysfunction will be assessed using aCTH stimulation test and measurements of plasma arginine vasopressin (aVP), aCTH and cortisol. Postoperatively the HPa axis response to surgical stress will be examined by measuring plasma aVP, aCTH and cortisol. once all samples are collected, they will be sent to Quest Diagnostics for analysis of cortisol, aCTH and aVP using tandem-mass-spectroscopy. This has major advantages in that it provides very accurate measurements of each hormone, and importantly, it also separates total and unconjugated cortisol, which is not readily available using other methods. To compare pre- and post-operatively clinical courses, variables such as vasopressor requirement, heart rate, blood pressure, mechanical ventilation indices, renal and liver functions and neurological status will be recorded for 4d includes 3d postoperative. Based on these variables, the Vasoactive inotropic Score (ViS) and Pediatric Logistic organ Dysfunction (PeLoD) score will be calculated and used as a tool to assess hemodynamic instability and severity of illness pre- and post-operatively; they also will be used to compare neonates with and without evidence of HPa axis dysfunction.
20 neonates who are screened for eligibility but not consented will be selected at random for analysis. These neonates will have basic demographic data (ethnicity, gestational age, birth weight, gender, route of delivery, apgars, age at admission to the hospital, date of surgery, iCu length of stay) extracted without any identifying information. These data will be compared to our enrolled study patients in order to show that the study population is representative of the general patient population.
a. Neonates with CHD born >= 35 wks EGA.
b. Admitted to CVICU at CMC for cardiac surgery.
c. Less than 30 d postnatal at the time of surgery.
d. Written informed parental consent.
Note: We will enroll subjects who speak any language.