Effect of a dynamic positioning–assisted dialysis nursing model on dry weight attainment

Background: : Based on the concept of Hydrostatic Indifference Plane（HIP），investigate the hemodynamic effects of the combined Passive Leg Raising(PLR) and Tilt position on maintenance hemodialysis (MHD) patients, with a focus on preventing intradialytic hypotension (IDH) and hypertension during dialysis blood reinfusion, thereby improving the achievement rate of Dry Weight (DW). Registry:Medical Ethics Committee of China Three Gorges University, TRN: 2022BA002, Registration date: 25 February 2022. Data Availability Statement All data generated or analyzed during this study are included in this published article (and its supplementary information files).For further inquiries, please contact the corresponding author. Funding Sources No specific financial support was obtained for the preparation of this article. Methods: 72 MHD patients were randomly divided into an observation group and a control group (36 each). Using the Fresenius 4008S dialyzer's relative blood volume (RBV) monitoring, the control group stopped ultrafiltration when the RBV curve dropped sharply, while the observation group maintained PLR. If the RBV curve rebounded, ultrafiltration was resumed with an extra 150–500 ml; if it plateaued, the current weight was set as provisional DW. Compare the overhydration (OH), total body water (TBW), extracellular water (ECW), intracellular water (ICW), as well as the systolic blood pressure （SBP）、diastolic blood pressure（DBP）、mean arterial pressure（MAP） at the start of dialysis, the end of ultrafiltration, and the end of dialysis blood reinfusion between the two groups.Over 3 months, indicators like IDH incidence, ultrafiltration adjustments, Overhydration(OH), TBW、ECW、ICW and DW compliance rate were compared. Results: Both groups of patients underwent 1,296 dialysis sessions. The observation group had significantly fewer cases of IDH than the control group (288 vs. 432 sessions), with a higher ultrafiltration volume (3.1±0.52 vs. 2.8±0.34 L). Marked improvements were observed in OH, TBW, ECW and ICW in the observation group. At the end of ultrafiltration, the SBP , DBP and MAP in the observation group were all higher than those in the control group; whereas at the end of blood reinfusion, the SBP, DBP and MAP in the observation group were lower than those in the control group. Additionally, the observation group achieved a notably higher DW compliance rate (94.44% vs. 36.11%, all P <0.01). Conclusion: Dynamic positioning adjusts fluid distribution, effectively prevents IDH, ensures ultrafiltration completion, and boosts DW compliance.