https://www.vmedtechnology.com/Post-surgical%20deaths.pdf

The risk of death: the confidential enquiry into perioperative small animal fatalities.

Equine perioperative fatalities associated with general anaesthesia at a private practice – a retrospective case series

Background Cats are commonly anaesthetized in veterinary practice, but recent figures describing the frequency of or risk factors for anaesthetic-related death are not available. The aims of this study were to address these deficiencies. Methods A nested case–control study was undertaken in 117 UK veterinary centres. All anaesthetic and sedation procedures and anaesthetic and sedation-related deaths (i.e. ‘cases') occurring within 48 h were recorded. Details of patient, procedure, and perioperative management were recorded for all cases and randomly selected non-deaths (controls). A detailed statistical model of factors associated with anaesthetic and sedation-related death was constructed. Results Between June 2002 and June 2004, 175 deaths were classified as anaesthetic and sedation-related and 14 additional deaths (with insufficient information to be excluded) were included for the estimation of risk. During the study, 79 178 anaesthetic and sedation procedures were recorded and the overall risk of anaesthetic and sedation-related death was 0.24% (95% CI 0.20–0.27). Factors associated with increased odds of anaesthetic-related death were poor health status (ASA physical status classification), increasing age, extremes of weight, increasing procedural urgency and complexity, endotracheal intubation, and fluid therapy. Pulse monitoring and pulse oximetry were associated with reduced odds. Conclusions The risk of anaesthetic-related death in cats appears to have decreased since the last published study in the UK. The results should aid the preoperative identification of cats at greatest risk. Greater care with endotracheal intubation and fluid administration are recommended, and pulse and pulse oximetry monitoring should be routinely implemented in cats.

Risk factors for anaesthetic-related death in cats: results from the confidential enquiry into perioperative small animal fatalities (CEPSAF)

Anaesthetic complications have been studied intermittently in small animal practice. Current estimates suggest that approximately 0.1-0.2% of healthy and 0.5-2% of sick dogs and cats die of an anaesthetic-related death. This is substantially greater than the risk of mortality reported in human anaesthesia. Recent work has identified the post-operative period as the highest risk period and has documented a number of risk factors for mortality. Knowledge of factors associated with anaesthetic-related death and high risk peri-operative periods could aid patient management and reduce complications.

Perioperative mortality in small animal anaesthesia.

SPECIAL ARTICLE Risk factors for anaesthetic-related death in cats: results from the confidential enquiry into perioperative small animal fatalities (CEPSAF) †

The confidential enquiry into perioperative equine fatalities (CEPEF): mortality results of Phases 1 and 2.

Reasons for performing study Approximately 1 in 100 horses suffer unexpectedly from anaesthetic-related death. Identification and use of the safest anaesthetic drugs should support this aim. Experimental evidence has suggested that isoflurane should be a safer maintenance agent in equine anaesthesia than halothane. Hypothesis The death rate would be reduced in horses being maintained with isoflurane compared to halothane. Methods A multicentre randomised controlled trial was undertaken to compare the effects of isoflurane and halothane for maintenance of equine anaesthesia for all types of operation. Data were analysed from 8242 horses in which anaesthesia was maintained with either halothane or isoflurane using mixed effects logistic regression models. Results No overall benefit of either drug was detected. However, although not part of the primary hypothesis, data showed that the overall death rate was significantly reduced in horses age 2-5 years with isoflurane and that death from cardiac arrest was also reduced with isoflurane, particularly in high risk cases. Conclusions and potential relevance Halothane remains an acceptable anaesthetic for maintenance of anaesthesia in horses, but isoflurane may be safer in the young horse and in high risk cases.

G. M. Johnston

Papers

The confidential enquiry into perioperative equine fatalities (CEPEF): mortality results of Phases 1 and 2.

Is isoflurane safer than halothane in equine anaesthesia? Results from a prospective multicentre randomised controlled trial.