Using quarterly earnings to assess racing performance in 66 thoroughbreds after transendoscopic laser surgery for treatment of epiglottic entrapment.

Objective: To assess the outcome of transendoscopic laser surgery for the treatment of epiglottic entrapment (EE) and determine the influence of preoperative morphological characteristics on outcomes. Study design: Retrospective cohort study. Animals: Thoroughbred racehorses treated with transendoscopic laser surgery (n=66) and untreated cohorts (n=132). Methods: Medical, surgical, and race records of 66 horses treated with transendoscopic laser surgery were compared with untreated cohorts randomly selected from their last race presurgery. Postsurgery data were collated as number of starts and race winnings for each quarter after the date of surgery. Results: Treated horses performed worse (P=.002) than their untreated cohorts in their last race presurgery. Although treated horses raced fewer times (P<.001) and earned less money (P<.001) in the first quarter after surgery compared with untreated horses, quarterly earnings or starts did not differ between groups after the first quarter. Among variables tested, subepiglottic membrane resection was the only prognostic factor; horses requiring this resection raced fewer times (P=.001) but without a significant difference in earnings. Conclusion: Horses treated for EE via transendoscopic laser surgery returned to a performance standard comparable to their untreated cohorts by the second quarter postsurgery. Horses with entrapments requiring resection raced fewer times postoperatively than the untreated cohorts. Clinical significance: Treated horses can be expected to perform equivocally to that of untreated cohorts in all but the first quarter following surgery except in those cases where resection of the entrapping membranes is required.