Hemodynamic effects of high spinal anesthesia under general anesthesia in infants undergoing cardiac surgery: a retrospective cohort study.

BACKGROUND

High spinal anesthesia (HSA), in combination with general anesthesia (GA), has been proposed as a technique to reduce the surgical stress response while minimizing opioid use in cardiac surgery. However, concerns remain regarding the potential for HSA-induced hemodynamic instability, particularly in infants with congenital heart disease. Therefore, this study aimed to evaluate the impact of HSA on hemodynamic parameters in infants undergoing cardiac surgery.

METHODS

This single-center retrospective cohort study was conducted at a tertiary medical center and included pediatric patients aged 1 to 12 months who underwent non-emergent cardiac surgery between November 2010 and November 2021. Patients with a Risk Adjustment for Congenital Heart Surgery-1 (RACHS-1) score greater than 3 and those who received other forms of regional anesthesia were excluded. The study compared patients who received HSA combined with GA (HSA group) to those who received GA alone (GA group). The primary outcome was the incidence of sustained hypotension and bradycardia within the first 60 minutes post-anesthesia induction, using mean arterial pressure (MAP) and heart rate (HR) as indicators. Secondary outcomes included intraoperative pressor use, as well as average MAP and HR during the 60-minute post-anesthesia induction period.

RESULTS

A total of 202 cases were analyzed, comprising 51 in the HSA group and 151 in the GA group. The incidence of sustained hypotension did not differ significantly between the HSA and GA groups [39.2% vs. 40.4%, respectively; odds ratio (OR) 0.95, P=0.88], nor did the incidence of sustained bradycardia (11.8% vs. 6.6%, respectively; OR 1.9, P=0.24). Pressor use was also similar between the groups (9.8% vs. 11.9%, respectively; OR 0.81, P=0.70). Although the HSA group showed significantly lower average, minimum, and maximum HRs post-induction, these differences were not considered clinically significant, as the HRs remained within clinically acceptable limits.

CONCLUSIONS

Adding HSA to GA in infants undergoing non-emergent fast-track cardiac surgery appears to be as clinically safe as GA alone with respect to hemodynamic stability, as assessed by MAP and HR within the first 60 minutes after anesthesia induction.