Accuracy and Correlation Between Bed Scale and Standing Scale Weights in Monitoring Volume Status in Patients Hospitalized for Acute Decompensated Heart Failure

Abstract

AbstractBackgroundAccurate monitoring of volume status is vital in managing diuretic therapy in patients with acute decompensated heart failure (ADHF). Guidelines recommend daily measurement of standing body weight as an indicator of volume status, though many healthcare facilities use bed scales instead. There is limited data surrounding the accuracy of bed scales compared to standing scales, and literature suggests discrepancy between the two. This study is the first to evaluate the accuracy and correlation between scales among patients hospitalized for ADHF.MethodsAdults (age ≥18) diagnosed with ADHF and its derivatives who were hospitalized at our center between March and April 2023 were identified via electronic medical record. Patients were included if they demonstrated capacity to consent and were medically cleared to ambulate independently. Participants’ weights were measured via bed scale and standing scale at the same time on each day of data collection. The mean difference (bias), precision [standard deviation (SD)], and limits of agreement (±2 SD) were calculated and graphed using the Bland-Altman method. Based on expert opinion, a bias of greater than ± 0.6 kg and precision greater than ± 3.0 kg were considered clinically significant.Results51 pairs of bed and standing scale weights were obtained among 43 patients. The mean difference ± precision between weights was 1.42 ± 1.18 kg (95% CI, -0.894 – 3.73), exceeding the recommended bias. In addition, 71% (n=36) of participants’ weights differed by more than 0.6 kg between the bed and standing scale, 22% (n=11) differed by more than 2.0 kg, and 5.9% (n=3) differed by more than 4.0 kg (see Table I).ConclusionsBed scales are not accurate compared to standing scales and may lead to errors in fluid management in patients hospitalized for acute decompensated heart failure.What is KnownAdequate diuresis and volume status optimization are mainstays of therapy in patients with acute decompensated heart failureGuidelines recommend measurement of standing body weight as an indicator of volume status, though many hospitals use bed scales insteadWhat the Study AddsThis is the first study to assess the difference in weights between bed and standing scales in patients hospitalized for acute decompensated heart failureThis study provides evidence that bed scale weights are not accurate compared to standing scale weights in this population