Preoperative computed tomographic evaluation of neonatal foals with rib fractures

Objective: To compare ultrasonographic and computed tomographic findings in neonatal foals prior to surgical repair of rib fractures as well as postoperative outcomes in foals with and without preoperative thoracic computed tomography (CT). Study design Retrospective cohort study. Sample population 43 neonatal foals undergoing surgical treatment of rib fractures between 2013 and 2021. Methods: Medical records were reviewed for age, sex, delivery method, comorbidities, presurgical anesthetic time, surgical time, number and location of fractured ribs identified with ultrasound and CT, number and location of ribs surgically repaired, survival to discharge, and post-mortem findings. Statistical analyses were performed using chi-square, Fisher's exact, and t-tests. Results: Twenty-two foals underwent surgical repair of rib fractures after preoperative CT from 2019-2021 (median: 4/18/20) and 21 foals were anesthetized (20 underwent repair) for surgical repair of rib fractures without preoperative CT from 2013-2020 (median: 4/9/15). Ultrasound and CT findings differed in number and location of fractured ribs in 13/17 (76%) foals (p = .049). More cranially positioned ribs were identified as fractured with CT than with ultrasonography (p = .035). Survival to discharge was improved when foals underwent CT (20/22, 91%) than when they did not (12/20, 60%, p = .019). Conclusion: Ultrasound findings differed from CT findings in most foals. Foals evaluated with CT were more likely to survive to hospital discharge. Clinical significance: When available, CT is recommended prior to surgical repair of rib fractures in neonatal foals.