Intradialytic Hypotension in Critically Ill Patients on Hemodialysis With A-Line versus B-Line Pattern on Lung Ultrasonography

Adequate volume removal in critically ill patients during hemodialysis can be limited due to intradialytic hypotension (IDH). Point of care ultrasonography (POCUS) is a reliable tool to aid in volume assessment. When an ultrasound wave passes the pleura into a normally aerated lung, the high acoustic mismatch causes some of the waves to reverberate. This creates a horizontal reverberation artifact, that when seen in all examined rib interspaces, is termed an “A-line pattern.” If an ultrasound wave meets a water-thickened interlobular septa beneath the pleural surface, the waves are reverberated in an air-fluid microenvironment, creating a linear reverberation artifact known as a “B-line.” A “B-line pattern” is noted if 3 or more B-lines are seen at 2 interspaces on both the left and the right hemi-thorax.