Suggestions have been made as to why rabbits have such high mortality rates compared with cats and dogs . Cardiorespiratory problems were related to 70 % of deaths in the single-centre study in 2018 , but only one mortality risk factor was identified : increased bodyweight [ 16 ] . In addition , a higher American Society of Anesthesiologists ( ASA ) classification was significantly associated with increased mortality in rabbits [ 2 , 16 ] . However , the ASA classification helps to predict a patient ' s perioperative risks based on comorbidities , and a higher grade indicates a greater risk , so this result is to be expected [ 18 ] .
Rabbits ' high metabolic rates make them prone to hypoglycaemia , and maintaining normothermia is difficult because of their high surface area to volume ratio [ 19 – 21 ] . Anaesthetists ' inexperience of the narrow pharyngeal inlet and reduced laryngeal visibility in rabbits , compared with cats and dogs , may cause difficulty when placing endotracheal tubes , resulting in ineffective oxygen and inhalant anaesthetic administration [ 2 , 8 , 20 , 22 , 23 ] . Additionally , intravenous catheter placement can be more challenging in small rabbits with fragile veins , thus reducing medication options [ 21 , 24 , 25 ] .
These hypothesised risks have not been empirically proven , whereas many studies in cats , dogs and horses have highlighted species-specific anaesthesia risks [ 17 , 26 – 29 ] ; therefore further study is required to identify whether the suggested causes of high mortality in rabbits are correct .
Rabbits are susceptible to stress on anaesthetic induction [ 20 ] , with catecholamine release resulting in slowing of gut motility followed by hepatic lipidosis and liver failure , potentially resulting in death [ 9 , 19 , 30 , 31 ] . Postoperative anorexia from the reduction in gut motility can lead to endotoxic shock from bacterial proliferation , increasing mortality [ 9 , 31 ] .
RVNs play an important role in reducing rabbits ' stress during hospitalisation as they usually provide the housing environment , handle the animals most frequently and closely monitor postoperative pain [ 32 ] . Therefore , they have a crucial role in preventing the stimulation of the sympathetic nervous system and gastrointestinal comorbidities that can result in death , which is of importance considering rabbits ' high incidence of gastrointestinal complications [ 16 ] .
Furthermore , 64 % of the deaths from the multicentre study in 2008 occurred postoperatively due to an unknown cause , suggesting that the rabbits were not sufficiently monitored in the recovery period [ 2 ] . The standards of monitoring during anaesthesia were also low ; often only respiration was monitored [ 2 ] . As RVNs monitor most anaesthetics in UK practices [ 3 , 8 ] , this inadequate monitoring may highlight a lack of confidence or lack of knowledge of typical parameters in rabbits and the monitoring techniques required .
Aims
This study aimed to ascertain whether confidence in rabbit anaesthesia truly is low ; to identify reasons why RVNs lack confidence with rabbit anaesthesia ; and to propose changes to improve RVNs ' confidence .
It was hypothesised that RVNs will feel less confident anaesthetising rabbits than they do anaesthetising cats or dogs , and that a lack of training would be the main barrier to confidence in rabbit anaesthesia .
The hypotheses directly address previously suggested theories that RVNs are apprehensive about treating rabbits because they see so few of them [ 11 ] and training in the area is lacking [ 14 , 15 ] .
If fatalities can be attributed to the opinion that rabbits are difficult to anaesthetise , then implementing the changes proposed by this study might help to reduce mortality and morbidity , by reducing apprehension and helping RVNs to provide rabbits with optimal care .
Materials and methods
This observational , cross-sectional study anonymously surveyed qualified RVNs working in the UK in 2019 , to obtain a high external validity from the representative sample population during the limited time frame [ 33 ] . An online format using JISC was chosen , with a lottery-style incentive to yield a high response rate [ 34 ] . Convenience sampling from a well-known Facebook group was used to obtain a representative sample of RVNs across the UK , working in various practice types and from different training routes . Sample-size calculations , based on an estimated number of 15,782 RVNs in the UK [ 35 ] and a 10 % margin of error , indicated that 96 participants were needed for sufficient statistical power [ 36 ] . Ethical approval was obtained from the Royal Veterinary College SSRERB ( Ref : SR2020-0273 ).
The questions elicited data from the RVNs about when they qualified , their training route and their confidence in anaesthetising cats , dogs and rabbits , along with other demographic data and relevant information about rabbit anaesthesia . A simple 1 – 10 numerical scale was used to assess confidence in anaesthesia for rabbits , cats and dogs , where 1 was ‘ not at all confident ’ and 10 was ‘ very confident ’. The year in which the RVNs qualified was asked to ascertain how many years they had practised as a VN , and this was later categorised into groups for ease of statistical analysis .
A Likert scale was used to collect information regarding confidence in specific areas of rabbit anaesthesia and potential barriers to this confidence , and two free-text questions were included at the end of the survey to gather additional information about ways to improve confidence . All of the questions in the online survey can be seen in Appendix 1 on page 45 .
36 Veterinary Nursing Journal