Dynamic ultrasound evaluation of inferior vena cava and lung B-lines predicts intradialytic hypotension in critically ill AKI patients

Débora Soares; Conrado Lysandro; José Hermógenes Rocco Suassuna; Renata de Souza Mendes

doi:10.1016/j.rmed.2026.108705

Dynamic ultrasound evaluation of inferior vena cava and lung B-lines predicts intradialytic hypotension in critically ill AKI patients

Respir Med. 2026 Mar:253:108705. doi: 10.1016/j.rmed.2026.108705. Epub 2026 Feb 3.

Authors

Débora Soares¹, Conrado Lysandro², José Hermógenes Rocco Suassuna², Renata de Souza Mendes³

Affiliations

¹ Clinical and Academic Unit of Nephrology, Faculty of Medical Sciences, Rio de Janeiro State University, Brazil; Nephrology Department, Galeão Air Force Hospital, Brazil.
² Clinical and Academic Unit of Nephrology, Faculty of Medical Sciences, Rio de Janeiro State University, Brazil.
³ Clinical and Academic Unit of Nephrology, Faculty of Medical Sciences, Rio de Janeiro State University, Brazil; Nephrology Department. Rio de Janeiro Federal University, Brazil. Electronic address: renata_mendes1981@hotmail.com.

PMID: 41643787
DOI: 10.1016/j.rmed.2026.108705

Abstract

Background: This study aimed to evaluate the utility of ultraportable ultrasound in predicting intradialytic hypotension (IDH) and early interruption of renal replacement therapy (RRT) due to hemodynamic instability, by assessing the inferior vena cava collapsibility index (IVCCi) and pulmonary B-lines (BL) in mechanically ventilated patients with acute kidney injury (AKI) undergoing RRT.

Methods: A total of 150 RRT sessions were evaluated in 72 mechanically ventilated patients with AKI. The IVCCi and BL were assessed at baseline (T0), 30 min (T30), and 60 min (T60) after initiation. Predictors of IDH and early session interruption were identified using generalized linear mixed models. Receiver operating characteristic (ROC) curve analysis was conducted to determine the predictive performance of the change in IVCCi between T0 and T30 (ΔIVCCi) and to identify a potential cutoff value.

Results: The IDH occurred in 57.3% of the sessions and early interruption occurred in 26%. Significant predictors of IDH included lower MAP at T0 (OR 0.92, p = 0.002), norepinephrine use (OR 2.67, p = 0.038), ΔIVCCi (OR 0.96, p = 0.031), and BL (OR 0.96, p = 0.007). Early interruption was associated with lower MAP at T0 (OR 0.93, p = 0.005), norepinephrine use (OR 11.04, p = 0.029), ΔIVCCi T30 (OR 0.94, p = 0.014), and BL T30 (OR 0.87, p = 0.034). ROC analysis for ΔIVCCi yielded an AUC of 0.601, with best cutoff of -9.315 (sensitivity, 87.5%; specificity, 65.1%).

Conclusions: IVCCi variation between T0 and T30 and pulmonary B-lines were predictive of IDH and early interruption of RRT in critically ill patients. The identified ΔIVCCi cutoff of -9.315 may serve as a practical tool for early risk stratification and timely adjustment of dialysis prescriptions within the first 30 min of therapy, potentially preventing hemodynamic instability and premature discontinuation.

Keywords: Acute kidney injury; Intradialytic hypotension; Point of care ultrasound; Renal replacement therapy.

MeSH terms

Acute Kidney Injury* / complications
Acute Kidney Injury* / physiopathology
Acute Kidney Injury* / therapy
Aged
Critical Illness
Female
Humans
Hypotension* / diagnosis
Hypotension* / diagnostic imaging
Hypotension* / etiology
Lung* / diagnostic imaging
Lung* / physiopathology
Male
Middle Aged
Predictive Value of Tests
ROC Curve
Renal Replacement Therapy* / adverse effects
Renal Replacement Therapy* / methods
Respiration, Artificial / methods
Ultrasonography / methods
Vena Cava, Inferior* / diagnostic imaging
Vena Cava, Inferior* / physiopathology