Epidural anaesthesia using ropivacaine, lidocaine or the combination of lidocaine and xylazine in dogs: cardiorespiratory and analgesic effects

Este estudo investigou o efeito da ropivacaína, da lidocaína e da associação de lidocaína e xilazina na anestesia epidural de cães. Trinta cães foram tranqüilizados com acepromazina intravenosa, distribuídos em três grupos e submetidos à anestesia epidural no espaço lombo-sacro, com lidocaína 2% com vasoconstrictor (GL), ropivacaína 1% (GR) ou com xilazina associada à lidocaína (GXL). Mensuraram-se as freqüências cardíaca (FC) e respiratória (f), a pressão arterial sistólica (PAS), a concentração final expirada de CO2 (EtCO2), o volume minuto (VM) e a temperatura retal (T). Para avaliação da analgesia somática, utilizou-se o teste do panículo e o teste térmico a 55°C. Os protocolos produziram anestesia da região retro-umbilical, sendo que a associação XL produziu bloqueio anestésico mais cranial, porém causou bradicardia moderada. A duração da anestesia foi mais prolongada nos animais dos grupos GXL (240 min) e GR (250 min), quando comparada as do grupo GL (120 min).This study was aimed at investigating the effects of ropivacaine, lidocaine or lidocaine combined with xylazine for epidural anaesthesia in dogs. Thirty dogs were sedated with acepromazine IV, divided in to three groups and submitted to lumbosacral epidural anaesthesia using 2% lidocaine with adrenaline (L) or 1% ropivacaine (R) or xylazine combined with lidocaine (XL). Heart and respiratory rates, systolic arterial blood pressure, EtCO2, minute volume and temperature were measured. Cutaneous anaesthesia was investigated using a forceps and thermic stimulus. All protocols produced retroumbilical anaesthesia. The combination of XL produced a more cranial anaesthetic block, with moderate bradycardia. The duration of the anaesthesia was more prolonged in animals treated with XL (240min) and R (250min), when compared to L alone (120min)

Refinement and partial validation of the UNESP-Botucatu multidimensional composite pain scale for assessing postoperative pain in horses

Background: Quantification of pain plays a vital role in the diagnosis and management of pain in animals. In order to refine and validate an acute pain scale for horses a prospective, randomized, blinded study was conducted. Twenty-four client owned adult horses were recruited and allocated to one of four following groups: anaesthesia only (GA); pre-emptive analgesia and anaesthesia (GAA,); anaesthesia, castration and postoperative analgesia (GC); or pre-emptive analgesia, anaesthesia and castration (GCA). One investigator, unaware of the treatment group, assessed all horses at time-points before and after intervention and completed the pain scale. Videos were also obtained at these time-points and were evaluated by a further four blinded evaluators who also completed the scale. The data were used to investigate the relevance, specificity, criterion validity and inter-and intra-observer reliability of each item on the pain scale, and to evaluate construct validity and responsiveness of the scale.Results: Construct validity was demonstrated by the observed differences in scores between the groups, four hours after anaesthetic recovery and before administration of systemic analgesia in the GC group. Inter-and intra-observer reliability for the items was only satisfactory. Subsequently the pain scale was refined, based on results for relevance, specificity and total item correlation.Conclusions: Scale refinement and exclusion of items that did not meet predefined requirements generated a selection of relevant pain behaviours in horses. After further validation for reliability, these may be used to evaluate pain under clinical and experimental conditions