Closed-loop Double-vasopressor Automated System to Treat Hypotension During Spinal Anaesthesia for Caesarean Section

"Novel closed-loop system incorporating:~1. Continuous non-invasive arterial pressure (CNAP) monitor that measured and recorded hemodynamic data in real time.~2. Controller algorithm loaded onto a laptop computer that monitored the hemodynamic data from CNAP and determined if vasopressors should be administered.~3. Two syringe pumps loaded with phenylephrine and ephedrine that was activated by the controller algorithm."

Phenylephrine is a vasopressor drug that was administered when the participant's systolic blood pressure fell below 90% of baseline systolic blood pressure, with heart rate of at least 60bpm.

Ephedrine is a vasopressor drug that was administered when the participant's systolic blood pressure fell below 90% of baseline systolic blood pressure, with heart rate of less than 60bpm.

"Manual dosing system consisting:~1. Non-invasive intermittent blood pressure monitor that measured and recorded blood pressure at 1-minute intervals.~2. Attending anesthesiologist that noted the blood pressure readings and manually administered phenylephrine or ephedrine according to the algorithm."