Antimicrobial susceptibility of bacterial isolates from 33 thoroughbred horses with arytenoid chondropathy (2005-2019).

OBJECTIVE: To describe the prevalence and antimicrobial susceptibility of bacterial isolates cultured from surgical specimens of infected arytenoid cartilage and granulomas. STUDY DESIGN: Retrospective cohort study. ANIMALS: Thirty-three thoroughbred horses. METHODS: Hospital records were retrieved for all horses admitted to a referral hospital for arytenoid chondropathy surgery that had samples submitted for culture and sensitivity between 2005 and 2019. Descriptive analyses were performed. RESULTS: In total, 56 bacterial isolates were obtained. Gram-positive bacteria (58%), Gram-negative bacteria (54%), and anaerobes (33%) were cultured from samples. Fifty-eight percent of horses had multiple bacteria isolated. Streptococcus spp were the most common (32%), followed by Enterobacteriaceae (13%). Bacterial isolates were sensitive to ceftiofur (83%), followed by ampicillin (64%), tetracycline (48%), enrofloxacin (45%), trimethoprim-sulfamethoxazole (41%), and gentamicin (18%). Multidrug resistance (MDR) was present in 44% of bacterial isolates. CONCLUSION: A wide variety of bacteria was cultured, providing evidence that secondary opportunistic infection by common respiratory bacteria is likely a factor in arytenoid chondropathy. Multidrug resistance was higher than what has been previously reported in equine respiratory samples. Trimethoprim-sulfamethoxazole had low effectiveness. CLINICAL SIGNIFICANCE: Because culture and sensitivity testing is not available in the diagnosis of mild to moderate arytenoid chondropathy, the information from this study may allow for more targeted broad-spectrum antimicrobial treatment to limit disease progression when the disease is first identified. The antimicrobial susceptibilities and MDR found in this study emphasize the importance of following current antimicrobial guidelines and highlight the requirement for surgical intervention rather than continued medical treatment in cases that do not resolve with initial antimicrobial therapy.

Clinical Assessment of an Ipsilateral Cervical Spinal Nerve Block for Prosthetic Laryngoplasty in Anesthetized Horses.

The nociceptive blockade of locoregional anesthesia prior to surgical stimulation can decrease anesthetic agent requirement and thereby potential dose-dependent side effects. The use of an ipsilateral second and third cervical spinal nerve locoregional anesthetic block for prosthetic laryngoplasty in the anesthetized horses has yet to be described. Anesthetic records of 20 horses receiving locoregional anesthesia prior to laryngoplasty were reviewed and compared to 20 horses of a similar patient cohort not receiving locoregional anesthesia. Non-blocked horses were 11 times more likely to require adjunct anesthetic treatment during surgical stimulation (P = 0.03) and were 7.4 times more likely to receive partial intravenous anesthesia in addition to inhalant anesthesia (P = 0.01). No horse in the blocked group received additional sedation/analgesia compared to the majority of non-blocked horses (75%) based on the anesthetist's perception of anesthetic quality and early recovery movement. No difference in recovery quality was observed between groups (P > 0.99). Cervical spinal nerve locoregional anesthesia appears well-tolerated and useful in reducing cumulative anesthetic agent requirement and may decrease the need for additional sedation/analgesia in horses undergoing anesthetized prosthetic laryngoplasty.

Triple antithrombotic therapy following an acute coronary syndrome: prevalence, outcomes and prognostic utility of the HAS-BLED score.

AIMS: The aim of this study was to evaluate the prevalence of triple antithrombotic therapy (TT) (warfarin, aspirin and clopidogrel) in patients following an acute coronary syndrome (ACS), the bleeding risk compared to double antiplatelet therapy (DAPT) (aspirin and clopidogrel) and evaluate the accuracy of the HAS-BLED risk score in predicting serious bleeding events in TT patients. METHODS AND RESULTS: We retrospectively identified all ACS patients on TT upon discharge from the Coronary Care Unit at Skane University Hospital between 2005 and 2010. TT patients were compared to age- and sex-matched control patients discharged with DAPT. Major bleeding was defined in accordance with the HAS-BLED derivation study. A total of 2,423 patients were screened, of whom 159 (6.6%) were on TT. The mean age was 67.2 (±0.9) years. The most common indication for TT was atrial fibrillation (n=63, 39.6%) followed by apical akinesia (n=60, 37.8%), and the mean duration of TT was 3.7 (±0.3) months. Upon termination of TT, warfarin was discontinued in 82 (52.2%) patients and clopidogrel in 57 (36.3%) patients. The cumulative incidence of spontaneous bleeding events was significantly higher with TT compared to DAPT at one year (10.2% vs. 3.2%; p=0.01). The HAS-BLED score significantly predicted spontaneous bleeding events in TT patients (area under the receiver operating characteristic [ROC] curve 0.67; 95% CI=0.54-0.79; p=0.048). CONCLUSIONS: TT was relatively common following acute coronary syndrome and was associated with a threefold increase in major bleeding compared to DAPT at one year. The HAS-BLED risk score predicted bleeding events with moderate accuracy.

Intravenous continuous infusion of lidocaine for treatment of equine ileus.

OBJECTIVE: To determine if intravenous lidocaine is useful and safe as a treatment for equine ileus. STUDY DESIGN: Prospective double-blinded placebo-controlled trial. STUDY POPULATION: Horses (n = 32) with a diagnosis of postoperative ileus (POI) or enteritis and that had refluxed >20 L or had been refluxing for >24 hours. METHODS: Refluxing horses were administered lidocaine (1.3 mg/kg intravenously [IV] as a bolus followed by a 0.05 mg/kg/min infusion) or saline (0.9% NaCl) solution placebo for 24 hours. Variables evaluated included volume and duration of reflux, time to 1st fecal passage, signs of pain, analgesic use, heart rate and arrhythmias, respiratory rate, temperature, days of hospitalization, outcome (survival to discharge), and complications. RESULTS: Of the lidocaine-treated horses, 65% (11/17) stopped refluxing within 30 hours (mean+/-SD, 15.2+/-2.4 hours) whereas 27% (4/15) of the saline-treated horses stopped within 30 hours. Fecal passage was significantly correlated with response to treatment; horses that responded to lidocaine passed feces within 16 hours of starting the infusion. Compared with placebo treatment, lidocaine treatment resulted in shorter hospitalization time for survivors, equivalent survival to discharge, no clinically significant changes in physical or laboratory variables, and no difference in the rate of incisional infections, jugular thrombosis, laminitis, or diarrhea. Muscle fasciculations occurred in 3 lidocaine-treated horses (18%). CONCLUSION: IV lidocaine significantly improved the clinical course in refluxing horses with minimal side effects. CLINICAL RELEVANCE: At the infusion rate studied, IV lidocaine is safe and should be considered for the treatment of equine ileus.

Stress fractures of the tibia and humerus in Thoroughbred racehorses: 99 cases (1992-2000).

OBJECTIVE: To determine clinical characteristics of and outcome in Thoroughbred racehorses with tibial or humeral stress fractures. DESIGN: Retrospective study. ANIMALS: 99 Thoroughbreds with tibial or humeral stress fractures. PROCEDURE: Information obtained from the medical records included history, signalment, and clinical, radiographic, and scintigraphic findings. Outcome was determined by interviewing trainers, performing follow-up examinations, and analyzing race records. RESULTS: Seventy-four tibial stress fractures were identified in 61 Thoroughbreds, and 48 humeral stress fractures were identified in 39 Thoroughbreds (1 horse was included in both groups). Tibial stress fractures occurred most commonly in 2-year-old or unraced horses. Fractures were located in 1 of 3 sites in the tibia (most commonly, the caudolateral cortex of the mid-diaphysis) and 1 of 4 sites in the humerus (most commonly, the caudodistal cortex). Forty-four of 58 (76%) tibial stress fractures and 18 of 32 (56%) humeral stress fractures were identified radiographically. Humeral stress fractures involving the caudodistal cortex were not detected radiographically. Treatment consisted of rest and exercise restriction, and 49 of 61 (80%) horses with tibial stress fractures and 30 of 39 (77%) horses with humeral stress fractures returned to racing. Humeral stress fractures recurred in 6 horses. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that in Thoroughbred racehorses, tibial stress fractures occurred most commonly in unraced 2 year olds, whereas humeral fractures occurred most commonly in older horses that had raced previously. The prognosis for racing following treatment was good.