Introduction

The objectives were to evaluate 1) the agreement between thoracic point‐of‐care ultrasound (TPOCUS) and thoracic radiographs in cats with recent trauma and 2) correlate TPOCUS findings to ATT scores in a large population of traumatized cats.

Methods

Records of cats presenting to the intensive care unit of VetAgro Sup, Lyon between February 2014 and April 2021 were retrospectively reviewed. Cats with suspected or witnessed trauma that had TPOCUS and thoracic radiographs performed within 24 hours of admission were included. Thoracic radiographs and TPOCUS findings were assessed as “positive” or “negative.” Cats positive on TPOCUS and radiographs were assigned 1 to 5 different suspected diagnoses: pulmonary contusions/hemorrhages, pneumothorax, pleural effusion, pericardial effusion, and diaphragmatic hernia. To express level of agreement between the two imaging modalities the kappa coefficient and 95% CI were calculated with Graphpad. Interpretation of kappa values was based on Cohen values.

Results

One hundred and eleven cats were included (54 confirmed or suspected motor vehicular trauma, 53 high rise syndrome and 4 canine bite wounds). Suspected TPOCUS diagnoses included 60/111 pulmonary contusions, 19/111 pneumothorax, 3/111 pleural effusions and 3/111 diaphragmatic hernia. Thoracic radiography suspected diagnoses included 62/111 pulmonary contusions, 29/111 pneumothorax, 16/111 pleural effusions and 7/111 diaphragmatic hernia. There was a moderate level of agreement for general overall comparison between TPOCUS and thoracic radiography (Kappa= 0.480, 95% CI, 0,312–0,649), moderate agreement for pulmonary contusions/hemorrhages (Kappa= 0.454, 95% CI, 0,288–0,621), moderate agreement for pneumothorax (Kappa= 0.527, 95% CI, 0,340–0,714), fair agreement for pleural effusion (Kappa= 0.283, 95% CI, 0,028–0,538) and moderate agreement for diaphragmatic hernia (Kappa= 0.584, 95% CI, 0,220–0,948). Cats with positive TPOCUS had significantly higher median ATT score (4 vs. 3; P=0.0428) and respiratory score (1 vs. 0, P=0.0028) compared to negative TPOCUS cats.

Conclusions

This large retrospective study in traumatized cats confirmed previous results: agreement between TPOCUS and thoracic radiography is moderate for contusions/hemorrhages, pneumothorax, diaphragmatic hernia and fair for pleural effusion. Comparison with a reference standard (computed tomography) is needed to determine true specificity and sensitivity of TPOCUS to diagnose these lesions in cats.

E-mail: dr.pierreandrevidal@gmail.com