An evidence-based medicine approach to small animal anaesthetic mortality in a referral practice: the influence of initiating three recommendations on subsequent anaesthetic deaths.

OBJECTIVE: To evaluate anaesthetic death after implementation of recommendations and its risk factors in a small animal practice. STUDY DESIGN: Observational cohort study. ANIMALS: All cats and dogs anaesthetized at the Centre Hospitalier Vétérinaire des Cordeliers during two periods, from April 15th, 2008 to April 15th, 2010 (period 1) and from June 15th, 2010 to August 24th, 2011 (period 2). METHODS: Death occurring during or before full recovery from anaesthesia was recorded. At the end of period 1, a logistic regression model was generated to describe anaesthetic death and identify risk factors. Potential risk factors in our practice setting were identified, and three recommendations, relating to improving physical status and anaesthetic/analgesic regimen implemented for period 2. The relationship between anaesthetic death and recorded variables were analyzed, and where relevant, compared between periods. RESULTS: Six thousand two hundred and thirty-one animals underwent general anaesthesia. The overall death rate during period 1 was 1.35% (48 in 3546, 95% CI [1.0-1.7%]) and during period 2 was 0.8% (21 in 2685, 95% CI [0.6-1.2%]). For sick animals (ASA status 3 and over), the overall death rate was 4.8% (45 of 944 95% [CI 3.5-6.4%]) during period 1 and 2.2% (18 of 834 95% CI [1.3-3.5%]) during period 2; this represented a significant decrease in death rate in period 2 (p = 0.002). In period 2, the main factors associated with an increased odds ratio of anaesthetic death were poor health status (ASA physical status classification) and old age. Species, gender, anaesthetic regimen, the nature and urgency of the procedure were not associated with risk. CONCLUSION AND CLINICAL RELEVANCE: Following evidence based recommendations, the death rate related to anaesthesia was significantly decreased during period 2 compared to period 1. Application of evidence-based medicine may contribute to an effective approach to decrease death rates. Other factors, not monitored in this study, may also have had an impact.

Myelomeningocoele and a dermoid sinus-like lesion in a French bulldog.

A 2-year-old male French bulldog was presented for investigation of lumbosacral pain and hindlimb ataxia associated with urinary and fecal incontinence. Survey radiography, myelography, and computed tomography images were suggestive of a dermoid sinus with associated spina bifida. Surgical intervention led to a resolution of pain and neurological deficits. Histopathological analysis of the excised tissue was compatible with a myelomeningocoele of the 7th lumbar vertebra.

Méningo-myélocèle et lésion dermoïde s'apparentant à un sinus chez un Bouledogue français. Un Bouledogue français mâle âgé de deux ans a été présenté pour faire enquête sur une douleur lombo-sacrée et une ataxie des jambes postérieures associée à une incontinence urinaire et fécale. La radiographie, la myélographie et les images par tomodensitométrie pour faire enquête sur les symptômes suggéraient un sinus dermoïde avec spina-bifida connexe. L'intervention chirurgicale a donné lieu à une résolution de la douleur et des autres déficits neurologiques. L'analyse histopathologique du tissu excisé était compatible avec un méningo-myélocèle de la 7e vertèbre lombaire.(Traduit par Isabelle Vallières).

Risk of anaesthetic mortality in dogs and cats: an observational cohort study of 3546 cases.

OBJECTIVE: To evaluate the anaesthetic death risk for dogs and cats in a French private practice. STUDY DESIGN: Observational cohort study. ANIMAL POPULATION: All small animals anesthetized at the Centre Hospitalier Vétérinaire des Cordeliers between April 15th, 2008 and April 15th, 2010. METHODS: General anaesthesia was defined as a drug-induced unconsciousness characterised by a controlled and reversible depression of the central nervous system and analgesia, sufficient to allow endotracheal intubation. Patient outcome (alive or dead) was assessed at the end of anaesthesia defined as the meeting point of the return of consciousness, rectal temperature >36 °C and ability to maintain sternal recumbency. Death occurring during anaesthesia was recorded. Relationship between anaesthetic death and ASA status, species, age, nature of the procedure, anaesthetic protocol and occurrence of epidural administration of a combination of morphine and bupivacaine were analysed. RESULTS: During the study period 3546 animals underwent general anaesthesia. The overall death rate in the present study was 1.35% (48 in 3546, 95% CI 0.96-1.75). The death rate of healthy animals (ASA 1 and 2) was 0.12% (3 in 2602 95% CI 0.02-0.34). For sick animals (ASA status 3 and over), the overall death rate was 4.77% (45 in 944 95% CI 3.36-6.18). The death rates in the ASA 3, 4 and 5 categories were 2.90%, 7.58% and 17.33%, respectively. The main factor associated with increased odds of anaesthetic death in ASA categories 3 and over was poor health status (ASA physical status classification). The nature of the procedure the patient underwent and epidural administration of a combination of morphine and bupivacaine were not correlated with the occurrence of death during anaesthesia. Neither species nor age effects were detected. CONCLUSION AND CLINICAL RELEVANCE: Specific factors were associated with increased odds of anaesthetic death, especially poor health status. Efforts must be directed towards thorough preoperative patient evaluation and improvement of clinical conditions if possible. Identification of risk factors before anaesthesia should lead to increased surveillance by trained staff. This could result in better outcomes.