ANSiscope™: Can it be the crystal ball of cardiac anesthesia?

Abstract

Background: Autonomic dysfunction (AD) is infrequently evaluated preoperatively despite having profound perioperative implications. The ANSiscope™ is a monitoring device that quantifies AD. This study aims to determine the potential of the device to predict hypotension following anesthetic induction, occurrence of arrhythmias, and inotrope requirement for patients undergoing off-pump coronary artery bypass surgery (OPCAB). Study Design: Prospective observational double-blinded study. Materials and Methodology: Seventy-five patients undergoing OPCAB had their autonomic function assessed by ANSiscope™. They were classified into four groups based on their AD and compared to perioperative adverse events. Results: Patients with diabetes had a higher ANSindex ( P = 0.0263). They had a greater decrease in systolic blood pressure ( P = 0.001) and mean arterial pressure ( P = 0.004) postinduction, had an increased incidence of arrhythmias ( P = 0.009), required higher inotropic support immediately ( P = 0.010) and at 24 h after surgery ( P = 0.018), and longer duration of postoperative ventilation ( P < 0.001). They also had a higher incidence of emergency conversion of OPCAB to on-pump surgery ( P = 0.009). Conclusions: An increased association between AD as quantified by the ANSiscope™ and perioperative adverse outcomes was observed. An increased rate of emergency conversion of OPCAB to on-pump surgery with higher dysfunction was noted. The authors opine that the threshold for conversion must be lower in patients deemed to be at a higher risk. Proper evaluation of the autonomic nervous system empowers the anesthesiologist to anticipate and adequately prepare for complications.

Prevalence and predictors of preoperative cardiac autonomic dysfunction among elective neurosurgical patients: A prospective observational study

“…[ 9 ] The ANS index was reported to be >13.5 among 65% of cardiac surgical patients. [ 8 ] Based on the HRV parameters, Polderman et al . [ 12 ] reported a 68% prevalence of CAD among 82 patients who underwent major abdominal and cardiac surgeries.…”

“…Firstly, we assessed CAD by using a relatively novel device, ANSiscope™. Though this instrument has been used across diverse groups of patients,[ 5 6 7 8 9 ] its validation with conventional ANS assessment tools is needed before routine use in the perioperative setting. Secondly, we performed the ANS function assessments in the operating room’s preoperative holding area just before the induction of anaesthesia for surgery.…”

“…Real-time heart rate variability (HRV) assessment using the ANSiscope™ equipment informs about the sympathovagal balance. Previous studies have demonstrated this device’s validity[ 4 ] and utility in the perioperative period during electroconvulsive therapies,[ 5 ] cervical spine,[ 6 ] intracranial[ 7 ] cardiac,[ 8 ] and obstetric surgeries. [ 9 ]…”