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

OBJECTIVES

To assess the reliability of conventional automated oscillometric upper arm cuff (cuff ARM ): 1) when finger cuff monitoring (cuff FINGER ) 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 cuff FINGER , cuff ARM 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 cuff FINGER . In the 102 patients (29%) with poor fingertip perfusion-defined as a capillary refill time greater than 4 seconds-and/or hand edema, cuff ARM 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, cuff FINGER 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 cuff FINGER failed to display an AP measurement, cuff ARM 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 cuff FINGER may be suitable as a first-line tool due to its continuous nature. When unreliable or unavailable, cuff ARM provides reliable measurements, effectively detects hypotension and hypertension, and poses no significant risk to the patient.