Interrater reliability in assigning a lung ultrasound score.

Background And Purpose: Lung ultrasound (LUS) for physiotherapists is an emerging bedside tool. The LUS score of aeration presents as a possible means of assessing and monitoring lung aeration associated with respiratory physiotherapy treatments. There are no studies to date that have assessed the interrater reliability (IRR) of physiotherapists assigning the LUS score of aeration. This study assessed the IRR of assigning the LUS score among adult, mechanically ventilated patients in an intensive care unit with a clinical suspicion of acute lobar atelectasis.

Methods: A convenience sample of patients had an LUS performed by a physiotherapist, and images were independently reviewed by two physiotherapists. Each lung zone was assigned an LUS score between 0 and 3 (with 0 being normal aeration and 3 being complete consolidation, presence of effusion, or pneumothorax). IRR was assessed using the kappa statistic.

Results: A total of 1032 LUS images were obtained. Assigning of the LUS across all lung zones demonstrated substantial agreement with kappa 0.685 (95% confidence interval: 0.650, 0.720). Right (0.702 [0.653, 0.751]) and left (0.670 [0.619, 0.721]) lung zones also demonstrated substantial agreement.

Conclusion: We found substantial IRR between physiotherapists in assigning the LUS score in a mechanically ventilated adult population in the intensive care unit.

Australian New Zealand Clinical Trials Registration Number: ACTRN12619000783123.