Does lung ultrasound-guided ultrafiltration lead to better outcomes in acute kidney injury requiring intermittent hemodialysis: A randomized control trial

Abstract

Introduction

Optimization of ultrafiltration during hemodialysis is a critical parameter in achieving therapeutic efficacy and ensuring hemodynamic stability. While various modalities such as blood volume monitoring, inferior vena cava diameter assessment, natriuretic peptide levels, bioimpedance assay, and lung ultrasound have been widely explored in the context of maintenance hemodialysis, the concept of volume-guided ultrafiltration in dialysis patients with acute kidney injury remains unexplored.

Methods

Adult patients with acute kidney injury requiring dialysis, who were hemodynamically stable and not on ventilator support, without underlying lung pathology or cardiac failure, were randomized into two groups. All patients underwent 28-zone lung ultrasound before dialysis. The ultrafiltration was decided based on the treating physician's clinical judgment in controls. In the intervention group, the ultrafiltration orders prescribed by the treating physician were modified, based on the Kerley B line scores obtained by lung ultrasound. The rest of the dialysis prescriptions were similar. A postdialysis lung ultrasound was done in both groups to assess the postdialysis volume status 30 min after the dialysis session.

Results

A total of 74 patients undergoing hemodialysis for acute kidney injury were randomized. The baseline characteristics were comparable except for higher baseline B line score scores in the intervention arm. All patients received similar dialysis prescriptions. The lung ultrasound-guided ultrafiltration arm had a higher change in B line scores (BLS) from baseline (4 [0–9.5] vs. 0 [0–4]; p value 0.004) during the first dialysis session. The predialysis BLS indexed to ultrafiltration (mL/kbw/h) were significantly lower in controls, reflecting a relatively higher rate of ultrafiltration in controls compared with intervention (p = 0.006). The total number of dialysis sessions done in the control and intervention arm were 61 and 59, respectively. Among controls, 23/61 sessions (37.7%) had intradialytic adverse events, whereas, in the intervention arm, only 4/59 sessions (6.7) had any adverse intradialytic events (p < 0.01).

Conclusion

Lung ultrasound-guided ultrafiltration was associated with a better safety profile, as demonstrated by reduced intradialytic events.