Multimodal Noninvasive Monitoring of Arterial Pressure: Do Limitations of Finger Cuff Monitoring Compromise Upper Arm Measurements? A Post Hoc Analysis of Two Prospective Cohorts.

Abstract

Objectives: To assess the reliability of conventional automated oscillometric upper arm cuff (cuffARM): 1) when finger cuff monitoring (cuffFINGER) of arterial pressure (AP) is suspected to be unreliable due to poor fingertip perfusion and/or hand edema or 2) fails to provide a reading.

Design: Prospective observational study based on cohorts evaluating the CNAP (Dräger Medical) and ClearSight (Edwards Lifesciences) systems.

Setting: Three ICUs.

Patients: Adults with an arterial catheter and stable AP.

Interventions: Three sets of triplicate AP measurements-simultaneous readings from the cuffFINGER, cuffARM and, as a reference, arterial catheter-were collected for each patient.

Measurements and main results: We analyzed 352 patients: 214 with the CNAP and 138 with the ClearSight cuffFINGER. In the 102 patients (29%) with poor fingertip perfusion-defined as a capillary refill time greater than 4 seconds-and/or hand edema, cuffARM mean AP measurements (n = 304) never failed, met the International Organization for Standardization (ISO) 81060-2:2018 standard (bias ± sd: 2.2 ± 7.2 mm Hg), posed no or low risk of harm in 99.7% of cases, and demonstrated good ability to detect hypotension and hypertension (area under the receiver operating characteristic curve, 0.91 [95% CI, 0.87-0.94] and 0.92 [95% CI, 0.75-1], respectively). In these 102 patients, cuffFINGER failed to display a reading in 17 patients (17%), and if not, did not meet the ISO 81060-2:2018 standard. In 38 of 352 patients (11%) in whom the cuffFINGER failed to display an AP measurement, cuffARM met the ISO 81060-2:2018 standard for mean AP (bias ± sd: 1.7 ± 7.1 mm Hg). In the absence of failure and risk factors for erroneous measurements, ClearSight met the ISO 81060-2:2018 standard for mean AP, unlike the CNAP system.

Conclusions: In a multimodal, noninvasive strategy for AP monitoring, ClearSight cuffFINGER may be suitable as a first-line tool due to its continuous nature. When unreliable or unavailable, cuffARM provides reliable measurements, effectively detects hypotension and hypertension, and poses no significant risk to the patient.