MO724: Rating of the Water Status in HD-Patient by Lung Ultrasound and Bioimpedance

Abstract

Abstract BACKGROUND AND AIMS To compare the methods of bioimpedance analysis (BIA) and lung ultrasound in determining the fluid balance in HD-patients. METHOD: Comparative analysis was carried out in 101 patients aged 24–82 years; 48 women and 53 men, receiving HD three times a week, treatment experience >3 months and a duration of 1 HD-session > 210 min. Patients with permanent catheters and pacemakers were excluded from the study. Measurements were performed before and 30 min after the HD-session at 2 or 3 HD sessions/week with baseline Doppler imaging and laboratory monitoring. A quantitative assessment of B-lines (BLS-B-lines score) by ultrasound (Siemens Acuson X150 with CH5-2 convex probe) was based on the method of Picano et al., while the BIA (Bodistat Multiscan 5000) was based on an overhydration (OHY) indicator based on Lukaski et al.. Given the impossibility of determining the state of dehydration by lung ultrasound, normohydration was compared with the sum of normo- and dehydration by BIA. Statistical data processing was performed using the STATISTICA 12.0. To assess the relationship between BLS and OHY indicators, Spearman's rank correlation coefficient with a statistical significance level of < 0.05 was used. RESULTS Summery 202 measurements were performed. The intermediate data for both methods before and after HD completely coincided in 36 patients; before HD, they coincided in 57 patients and in 67 patients after. The data did not match in 13 patients either before or after HD. In 101 patients, a statistically significant correlation was found between BLS and OHY before (Rs = 0.366) and after HD (Rs = 0.362). Further studies in 101 patients revealed a correlation dependence of both methods with shortness of breath (before HD BLS Rs = 0.281, OHY Rs = 0.322; after HD BLS Rs = 0.233, OHY Rs = 0378), nutritional status according to BIA (before HD BLS Rs = 0.376, OHY Rs = 0.622; after HD BLS Rs = 0.299, OHY Rs = 0.788) and the maximum left atrial volume index according to Doppler images (before HD BLS Rs = 0.301, OHY Rs = 0.219; after HD BLS Rs = 0.202, OHY Rs = 0.266). Measurements performed before HD showed a correlation between both methods and the patient's age (BLS Rs = 0.236, OHY Rs = 0.413), NYHA functional class of CHF (BLS Rs = 0.269, OHY Rs = 0.200), as well as laboratory ALB up to HD (BLS Rs = –0.217, OHY Rs = –0.417), CRE before HD (BLS Rs = –0.243, OHY Rs = –0.353) and URE before HD (BLS Rs = –0.201, OHY Rs = –0.257). In studies after HD, both techniques correlated with the presence of lung fibrosis (BLS Rs = 0.335, OHY Rs = 0.218), functional bowel disorders (constipation) (BLS Rs = 0.244, OHY Rs = 0.255) and the diameter of the pulmonary artery according to Doppler images (BLS Rs = 0.245, OHY Rs = 0.240). CONCLUSION Bioimpedance remains the gold standard for assessing hyper-, normo- and dehydration in HD-patients. Lung ultrasound is a simple and adequate method for assessing the water status in HD-patients and is comparable in terms of information content with bioimpedance in assessing hyper- and normohydration. Lung ultrasound does not allow diagnosing the state of dehydration. Both techniques reflect both overhydration and left atrial dysfunction in our patient cohort and determine the relationship between heart failure and patient hydration status. Initial lung fibrosis and functional bowel disorders (constipation) affect the results of both methods and, possibly, limit their information content.