RESUMO
AIM: This study aimed to provide baseline information on the potential role of salivary cortisol in reflecting the stress response in children undergoing congenital heart surgery. PATIENTS AND METHODS: Children underwent congenital cardiac surgery, aged between one and seventeen years were included. Saliva samples were collected pre- and postoperatively by the health caregiver immediately after the children woke up (07:00-09:00 am) and at 06:00 pm in the evening. Salivary cortisol levels were compared with the reference index values from a large database. RESULTS: Median baseline preoperative morning salivary cortisol levels were significantly lower than the reference values in both < 5-year-old females (p = 0.01) and males (p = 0.04) and in males between 11 and 20 years of age (p = 0.01). Median baseline preoperative evening salivary cortisol levels were significantly higher than the reference value in < 5-year-old females (p = 0.01) and between 5 and 10 years of age (p = 0.04) and in between 11- and20-year-old males (p = 0.01). Median postoperative morning salivary cortisol levels were significantly lower than the reference value in both < 5-year-old females (p = 0.01) and males (p = 0.04) and females between 5 and 10 year of age (p = 0.04). Median postoperative evening salivary cortisol levels were significantly higher than the reference value in < 5-year-old females (p = 0.01) and between 5- and 10-year-old females (p = 0.04). CONCLUSION: Diurnal variability of salivary cortisol levels in children undergoing congenital heart surgery may be different from normal reference values both in preoperative and postoperative periods that can be a predictive indicator of anxiety on pre- and postoperative period for children that undergoing cardiac surgery.