Usefulness of a radial applanation tonometry device in blood pressure related clinical decision making by anesthesiologists

Abstract

Purpose: Radial artery tonometry (AT) can continuously measure arterial blood pressure (ABP) noninvasively. This study aimed to evaluate AT for continuous ABP monitoring during anesthesia and compared AT to invasive (IBP) and non-invasive (NIBP) ABP measurements at clinical decision-making moments. Methods: 243 patients undergoing elective surgery were prospectively included in the study and AT was applied on the right or left arm while IBP and NIBP were recorded simultaneously. At moments when the IBP signal required a clinical decision by the anesthesiologist for situations of hyper- or hypotension, comparison was made whether AT and NIPB signals would require a clinical decision as well. Agreement/discrepancy of clinical decision-making was analyzed, additionally bias, precision, and percentage error of AT was compared to IBP at these moments. Results: 513 clinical decision moments were recorded. Decision moments based on AT signal did not differ significantly from decision moments based on IBP (1 vs. 1; IQR, 1 – 2 vs. 0 – 3, P = 0.06), while NIBP based decision moments showed significant differences (0 vs. 1; IQR, 0 – 2 vs. 0 – 3, P＜0.001). Subgroup analysis of patients divided by age, BMI and surgery time also showed no significant differences between IBP and AT. Conclusions: ABP measurement using AT is feasible and safe. AT provides relevant and efficient information to anesthesiologists; at moments when IBP called for action, AT called for action as well, but not NIBP. AT also showed clinically satisfactory agreement with IBP at moments of hypo- and hypertension.