Value of B lines score on lung ultrasound as a direct measure of respiratory dysfunction and volume overload in critical care patients with acute kidney injury

Abstract

Background: Fluid overload is commonly detected in critically ill cases with AKI and is accompanied by serious outcome. Lung US (LUS) is an efficiently used tool to assess volume noninvasively. We assessed the importance of these measurements in combination, for estimation of the PaO2/FiO2 ratio in critical patients with AKI.The aim of the study: To evaluate the value of B-lines on chest ultrasound in predicting respiratory dysfunction in AKI and to assess the relation between the B lines on chest ultrasound and po2/fio2 ratio in acute kidney injury patients.Patients and methods: This was a prospective observational study in which 40 cases who were presented on admission or developed at any time during ICU stay acute kidney injury determined based on the KDIGO criteria and according to RIFLE classification. Cases were studied at baseline as well as following 48 hrs using lung US, in addition to measuring the arterial blood gases.Results: The PaO2/FiO2 ratio showed negative correlation with the B-lines score, and this correlation was kept even following adjustment. A cut of value of 15 for the B-lines score has a sensetivity of 94% and a specificity of 77.3% in detecting cases with PaO2/ FiO2 of less than 300.Conclusion: It can be concluded that B-lines on chest US can predict volume overload and respiratory dysfunction in cases with AKI.