Dissociative Anaesthesia in Foals for Umbilical Herniorrhaphy under Field Conditions

Abstract

The aim of the present study was to investigate the effects of a dissociative anaesthetic combination of xylazine-tiletamine-zolazepam, administered for the umbilical herniorrhapy of foals under field conditions, on certain cardiorespiratory and clinical anaesthesia parameters. Eleven foals diagnosed with umbilical hernia, of 4-7 months of age (mean age 5.73±0.91 months) and 130-175 kg body weight (mean body weight 152.55±14.35 kg), 7 of which were female and 4 were male, and 8 of which were Arabian horses and 3 were English horses, constituted the material of the study. The anaesthesia protocol was xylazine (1.1 mg/kg, iv), tiletamine-zolazepam (1.65 mg/kg, iv) and half of the indicated doses after observation of the first signs of recovery 3 times at 8-10 min-intervals for sustainment, together with the subcutaneous injection of approximately 12 ml 2% lidocaine peripheral to the hernial sac in a circular pattern for local anaesthesia. In all foals after last drug injection; anaesthesia induction time, operation time, anaesthesia time and standing time were recorded. Quality of induction, anaesthesia/analgesia and recovery were evaluated. Heart rate, respiratory rate, body temparature, arterial oxygen saturation values, mean arterial blood pressure were evaluated before anaesthesia (as a baseline) and after induction of anaesthesia at 15th, 30th, 45th, 60th and 90th min. After induction of anaesthesia cardiopulmonary parameters and body temparature were decreased below baseline values in first stage of anaesthesia and then they were reached to baseline values in late stage of anaesthesia. It was ascertained in the present study that, the supplementation of the combined use of xylazine-tiletamine-zolazepam in foals under field conditions with local anaesthetics induces an anaesthesia of adequate depth for umbilical herniorrhaphy, and sustaining doses enable the prolongation of the anaesthesia period with cardiorespiratory adverse effects remaining within acceptable limits. Therefore, it is considered that, the indicated anaesthesia protocol could be tested for other surgical interventions in foals under both field and clinical conditions. Keywords: Xylazine, Tiletamine-Zolazepam, Dissociative anaesthesia, Field condition, Foal Saha Şartlarında Taylarda Umblikal Herniorafi İçin Dissosiyotif Anestezi ÖzetSunulan bu çalışmanın amacı, saha şartlarında taylarda umblikal herniorafi operasyonu için uygulanan ksilazin-tiletamin-zolazepam dissosiyatif anestezik kombinasyonunun bazı kardiyopulmoner ve klinik anestezi parametreleri üzerine olan etkilerini araştırmaktı. Çalışmada, yaşları 4-7 ay arasında değişen (ortalama 5.73±0.91); canlı ağırlıkları 130-175 kg (ortalama 152.55±14.35); 7'si dişi, 4'ü erkek; 8'i Arap, 3'ü İngiliz ırkı olan, toplam 11 adet göbek fıtığı tanısı konulan tay kullanıldı. Taylarda anestezi protokolü olarak; ksilazin (1.1 mg/kg, iv), tiletamin-zolazepam (1.65 mg/kg, iv) ve belirtilen dozların yarısı ilk uyanma belirtisinden sonra ortalama 8-10 dakikada bir 3 kez idame olarak ve lokal anestezik olar...