Advertisement

Twenty years later: a single-centre, repeat retrospective analysis of equine perioperative mortality and investigation of recovery quality

      Abstract

      Objectives

      To determine the mortality rates associated with equine anaesthesia for elective and emergency (colic and non-colic) cases in one equine, university teaching hospital and to investigate the effect of several horse- and anaesthetic-related variables on anaesthetic recovery quality.

      Study design

      Retrospective data analysis.

      Animals or animal population

      In total, 1416 horses undergoing anaesthesia between May 2010 and December 2013.

      Methods

      Patient information and details of the anaesthetic, recovery period and immediate complications were extracted from an archiving database. Statistical evaluation of factors affecting mortality included chi-squared tests and binary logistic regression. Factors affecting recovery quality were investigated using univariable and multivariable ordinal logistic regression. Statistical significance was set at p < 0.05.

      Results

      Anaesthesia/recovery-related mortality was 1.1% for all cases, 0.9% for elective cases, 1.6% for colics and 0% for non-colic emergencies. Fractures and dislocations accounted for the majority (71.4%) of deaths. No intra-operative deaths occurred during the study period. Risk factors for mortality included increasing age and American Society of Anesthesiologist's (ASA) status but these and other factors were confounded by ‘colic’. Non-fatal complications in the immediate recovery period included postanaesthetic myopathy/neuropathy and postanaesthetic respiratory obstruction. Recovery quality was associated with body mass (p = 0.016), ASA status 3 and 4 (p = 0.020 and 0.002, respectively), duration of anaesthesia (p < 0.001) and out-of-hours anaesthesia (p = 0.013). Although recovery quality was also influenced by age and breed-type, these factors were removed from the final model as age was highly associated with both ASA status (p < 0.001) and colic surgery (p < 0.001), and breed-type was a determinant of body mass.

      Conclusion and clinical relevance

      Anaesthetic/recovery-associated mortality was comparable to previously reported figures except intra-operative deaths were not reported. Fractures remained responsible for the largest proportion of recovery-associated deaths. Improvements to the recovery process that can reduce fracture occurrence are still required.

      Keywords

      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'

      Subscribe:

      Subscribe to Veterinary Anaesthesia and Analgesia
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect

      References

        • Bidwell LA
        • Bramlage LR
        • Rood WA
        Equine perioperative fatalities associated with general anaesthesia at a private practice - a retrospective case series.
        Vet Anaesth Analg. 2007; 34: 23-30
        • Brodbelt DC
        • Blissitt KJ
        • Hammond RA
        • et al.
        The risk of death: the Confidential Enquiry into Perioperative Small Animal Fatalities.
        Vet Anaesth Analg. 2008; 35: 365-373
        • Clark-Price SC
        Recovery of horses from general anaesthesia.
        Vet Clin North Am: Eq Pract. 2013; 29: 223-242
        • Duke T
        • Filzek U
        • Read MR
        • et al.
        Clinical observations surrounding an increased incidence of post-anesthetic myopathy in halothane-anesthetized horses.
        Vet Anaesth Analg. 2006; 33: 122-127
        • Franci P
        • Leece EA
        • Brearley JC
        Post-anaesthetic myopathy/neuropathy in horses undergoing MRI compared to horses undergoing surgery.
        Equine Vet J. 2006; 38: 497-501
        • Glade MJ
        Effects of gestation, lactation and maternal calcium intake on mechanical strength of equine bone.
        J Am Coll Nutr. 1993; 12: 372-377
        • Grosenbaugh DA
        • Muir WW
        Cardiorespiratory effects of sevoflurane, isoflurane and halothane anesthesia in horses.
        Am J Vet Res. 1998; 59: 101-106
        • Johnston GM
        • Taylor PM
        • Homes MA
        • et al.
        Confidential enquiry of perioperative equine fatalities (CEPEF-1): preliminary results.
        Equine Vet J. 1995; 27: 193-200
        • Johnston GM
        • Eastment JK
        • Wood JLN
        • et al.
        The confidential enquiry into perioperative equine fatalities (CEPEF): mortality results of Phases 1 and 2.
        Vet Anaesth Analg. 2002; 29: 159-170
        • Jones RS
        Comparative mortality in anaesthesia.
        Br J Anaesth. 2001; 87: 813-815
        • Kaestner SBR
        How to manage recovery from anaesthesia in the horse – to assist or not to assist?.
        Pferdeheilkunde. 2010; 26: 1-5
        • McMillan M
        • Brearley J
        Assessment of the variation in American Society of Anesthesiologists Physical Status Classification assignment in small animal anaesthesia.
        Vet Anaesth Analg. 2013; 40: 229-236
        • Mee AM
        • Cripps PJ
        • Jones RS
        A retrospective study of mortality associated with general anaesthesia in horses: elective procedures.
        Vet Rec. 1998; 142: 275-276
        • Mee AM
        • Cripps PJ
        • Jones RS
        A retrospective study of mortality associated with general anaesthesia in horses: emergency procedures.
        Vet Rec. 1998; 142: 307-309
        • Senior JM
        • Pinchbeck GL
        • Allister R
        • et al.
        Reported morbidities following 861 anaesthetics given at four equine hospitals.
        Vet Rec. 2007; 160: 407-408
        • Southwood LL
        • Baxter GM
        • Wagner AE
        Abstract: severe postanesthetic upper respiratory tract obstruction in horses: 8 cases (1993–2001).
        Vet Surg. 2003; 32: 602
        • Suthers JM
        • Christley RM
        • Clutton RE
        Quantitative and qualitative comparison of three scoring systems for assessing recovery quality after general anaesthesia in horses.
        Vet Anaesth Analg. 2011; 38: 352-362
        • Thomas SJ
        • Corbett WT
        • Meyer RE
        Abstract: risk factors and comparative prevalence rates of equine postanesthetic respiratory obstruction at NCSU.
        Vet Surg. 1987; 16: 324
        • Vettorato E
        • Chase-Topping ME
        • Clutton RE
        A comparison of four systems for scoring recovery quality after general anaesthesia in horses.
        Equine Vet J. 2010; 42: 400-406
      1. Wilderjans H (20052005) Advances in assisted recovery from equine anaesthesia. Proceedings of the 44th Congress of the British Equine Veterinary Association, Harrogate, UK. pp. 36–38.

        • Young SS
        • Taylor PM
        Factors influencing the outcome of equine anaesthesia: a review of 1, 314 cases.
        Equine Vet J. 1993; 25: 147-151