A retrospective comparison of postoperative outcomes in ovariectomised jennies (Equus asinus) treated with phenylbutazone or flunixin meglumine

Abstract

AbstractBackgroundClinically, flunixin meglumine (FM) and phenylbutazone (PBZ) are preferentially selected for the treatment of visceral and musculoskeletal pain, respectively, in horses. In donkeys, there is no information to support or refute this conventional conjecture.ObjectivesTo compare postoperative outcomes in a group of jennies treated with intravenous FM or oral PBZ.AnimalsFourteen jennies unilaterally ovariectomised by standing left flank laparotomy.Study designRetrospective cohort study.MethodsData from medical records of ovariectomised jennies (case details, weight, non‐steroidal anti‐inflammatory drug [NSAID] protocol, surgery duration, operative sequence, anaesthesia protocol, physical examination findings and outcomes) were collected. From collated data, postoperative adverse events were defined as fever, tachycardia, tachypnea, inappetence, altered mentation, abnormal oral mucous membranes, bruxism, colic, incisional complications (i.e., drainage, oedema, peri‐incisional emphysema and pain) and non‐survival, then further divided into occurrence during the early (≤24 h) or late (>24 h) postoperative period for data analysis using R software. Chi‐squared test was used to compare individual adverse events between groups (PBZ vs. FM) and moments (early vs. late). Significance was set at p ≤ 0.05.ResultsPBZ treatment (8/14) was associated with (odds ratio, 95% confidence interval) more total (2.93, 1.97–4.36), early (3.01, 1.87–4.84) and late (2.69, 1.28–5.63) adverse events than FM treatment (6/14). Tachycardia (37.83, 2.21–646.66), tachypnoea (0.29, 0.13–0.66), altered mentation (2.78, 1.01–7.67), altered mucous membranes (18.38, 1.04–325.23), incisional oedema (44.33, 2.60–754.5) and incisional pain (47.78, 2.81–811.61) were significantly different between groups. Early adverse events significantly different between groups included tachycardia (50.2, 2.9–877.0), altered mentation (3.33, 1.08–10.29) and incisional pain (21.0, 1.2–374.5), with late adverse events being tachypnea (0.07, 0.01–0.62), incisional oedema (32.92, 1.85–584.28) and incisional pain (28.92, 1.62–515.68). Colic (2/8) and non‐survival (1/8) were rare events that only occurred in the PBZ cohort and could not be further evaluated for differences.Main limitationsSmall sample size; retrospective study; treatment bias; varied administration routes.ConclusionsOral PBZ may be inappropriate to use following abdominal surgery in donkeys.Clinical relevanceMore prospective and case‐controlled studies are needed to evaluate the clinical efficacy of these two NSAIDs in donkeys.