Validation of non‐invasive haemodynamic methods in patients with liver disease: the Finometer and the Task Force Monitor

Abstract

Patients with advanced cirrhosis often present a hyperdynamic circulation characterized by a decrease in systolic and diastolic blood pressure (SBP and DBP), and an increase in heart rate (HR) and cardiac output (CO). Accurate assessment of the altered circulation can be performed invasively; however, due to the disadvantages of this approach, non-invasive methods are warranted. The purpose of this study was to compare continuous non-invasive measurements of haemodynamic variables by the Finometer and the Task Force Monitor with simultaneous invasive measurements. In 25 patients with cirrhosis, SBP, DBP and HR were measured non-invasively and by femoral artery catheterization. CO was measured non-invasively and by indicator dilution technique. The non-invasive pressure monitoring was considered acceptable with a bias (accuracy) and a SD (precision) not exceeding 5 and 8 mmHg, respectively, as recommended by the Association for the Advancement of Medical Instrumentation. The accuracy and precision of the Finometer and the Task Force Monitor were as follows: SBP: -3·6 ± 17·9 and -8·9 ± 17·5 mmHg, respectively; DBP: 4·2 ± 9·6 and 1·9 ± 8·6 mmHg, respectively; HR: 2·0 ± 6·9 and 2·2 ± 6·2 bpm, respectively; and CO: 0·1 ± 1·6 and -1·0 ± 2·0 L min , respectively. The study demonstrates that the overall performances of the Finometer and the Task Force Monitor in estimating absolute values of SBP, DBP, HR and CO in patients with cirrhosis are not equivalent to the gold standard, but may have an acceptable performance with repeated measurements.

Comparison of the sit-up test and head-up tilt test for assessing blood pressure and hemodynamic responses in healthy young individuals

“…The right arm was supported by a sling, so that the finger cuff remained at the level of the heart. Continuous measurements of beat-to-beat SBP and DBP were obtained using the vascular unloading technique on the finger [ 24 , 25 ]. These blood pressure values were automatically and continuously corrected to oscillometric blood pressure values obtained in the left arm.…”

Baroreflex function, haemodynamic responses to an orthostatic challenge, and falls in haemodialysis patients

“…This relatively low BP may be explained in light of the strict testing standardisation procedures which were designed to ensure the best possible haemodynamic state balance (e.g. no caffeine, supine rest prior to the assessment, non-dialysis day), and also by a possible underestimation of BP from the Task Force Monitor [32]. Although this should not affect the study results, since the research aim was focused on exploring the relationship between the relative change in BP and falls, rather than the absolute values of BP, the generalisability of the study results to patients with higher or more poorly controlled resting BP should be cautious.…”

Determination of hepatic clearance by derivations of the indocyanine green retention test in cirrhosis

“…Heart rate (HR) was determined by electrocardiography. 25 Indocyanine green-clearance, ICG-r15, and its derivations. The ICG-clearance was measured as the constant infusion rate of ICG divided by the arterial plasma concentration according to Stewards principle.…”