Continuous finger-cuff versus intermittent oscillometric arterial pressure monitoring and hypotension during induction of anesthesia and non-cardiac surgery: The DETECT randomized trial

Background: Finger-cuff methods allow non-invasive continuous arterial pressure monitoring. We aimed to determine whether continuous finger-cuff arterial pressure monitoring helps clinicians reduce hypotension within 15 minutes after starting induction of anesthesia and during non-cardiac surgery. Specifically, we tested the hypotheses that continuous finger-cuff - compared to intermittent oscillometric - arterial pressure monitoring helps clinicians reduce the area under a mean arterial pressure (MAP) of 65 mmHg within 15 minutes after starting induction of anesthesia, and the time-weighted average MAP <65 mmHg during non-cardiac surgery.

Methods: In this single-center trial, 242 non-cardiac surgery patients were randomized to unblinded continuous finger-cuff or to intermittent oscillometric arterial pressure monitoring (with blinded continuous finger-cuff arterial pressure monitoring) within 15 minutes after starting induction of anesthesia and during surgery. The first of two hierarchical primary endpoints was the area under a MAP of 65 mmHg within 15 minutes after starting induction of anesthesia, the second primary endpoint was the time-weighted average MAP <65 mmHg during surgery.

Results: Within 15 minutes after starting induction of anesthesia, the median (interquartile range) area under a MAP of 65 mmHg was 7 (0, 24) mmHg x min in 109 patients assigned to continuous finger-cuff monitoring versus 19 (0.3, 60) mmHg x min in 113 patients assigned to intermittent oscillometric monitoring (p = 0.004; estimated location shift -6 [95%-CI: -15, -0.3] mmHg x min). During surgery, the median (interquartile range) time-weighted average MAP below 65 mmHg was 0.04 (0, 0.27) mmHg in 112 patients assigned to continuous finger-cuff monitoring and 0.40 (0.03, 1.74) mmHg in 115 patients assigned to intermittent oscillometric monitoring (p < 0.001; estimated location shift -0.17 [95%-CI: -0.41, -0.05] mmHg).

Conclusion: Continuous finger-cuff arterial pressure monitoring helps clinicians reduce hypotension within 15 minutes after starting induction of anesthesia and during non-cardiac surgery compared to intermittent oscillometric arterial pressure monitoring.