New Postgraduate Certificate Programmes New programmes starting in 2021 Find out more

Minimising mistakes in veterinary anaesthesia: steps to safer practice

Minimising error and striving for optimal patient safety is the responsibility of the whole veterinary team and can be achieved using an evidence-based, committed and coordinated team approach

08 April 2021, at 9:00am

Optimising patient safety has become a central component of modern medicine and more specifically anaesthesia (McMillan, 2014). While surgery-related errors have consistently been frequently reported in both medical and veterinary practice, the results of a veterinary focus group found that anaesthesia-related errors were commonly discussed (Oxtoby et al., 2015).

Anaesthesia is inherently risky (Oxtoby et al., 2015) and complex situations, adverse events and intraoperative complications can escalate rapidly and become life-threatening. Ensuring patient safety is a fundamental remit of any anaesthetist (McMillan, 2014) and, over the last 10 years, patient safety research has increased within the veterinary profession.

Although anaesthetic-related fatalities have reduced over the last 20 years in small animal practice, they are still far behind those in human anaesthesia (Mellin-Olsen et al., 2010; Bainbridge et al., 2012; McMillan, 2014). Fatality figures alone do not reflect the incidence of error and just as most deaths do not involve medical error, most medical errors do not produce death; however, they can still produce substantial morbidity, costs, distress and enduring suffering (Shojania and Dixon-Woods, 2017). Patient safety should be at the forefront of everything we do as anaesthetists (McMillan, 2014) and a concerted unified effort is required to drive forward patient safety in our veterinary patients.

What causes error?

Adverse events are rarely due to an isolated event but more commonly a result of a complex interaction of a series of events. The “Swiss Cheese Model” of error (Reason, 2004) illustrates the existence of a chain of circumstances which line up and culminate in patient harm. The “holes” in the system may be system failures such as organisational deficits or active failures involving cognitive limitations of the individual clinician who may represent the final fallible link in the chain (Oxtoby et al., 2015). Systemic organisational failures can occur as a result of environmental influences and communication breakdowns. Cognitive limitations may account for a large proportion of errors (Oxtoby et al., 2015) and may be further exacerbated by stress, time pressures, distraction, inexperience and mental fatigue. Technical and non-technical skills play equally important roles in the delivery of safe and efficient practice. Deficiencies in non-technical skills at the individual level increase the chance of errors and adverse events (Flin et al., 2010).

A large-scale audit of airway complications in medical practice in the UK found that human factors were relevant in every case (Cook et al., 2011). Emergency or unfamiliar situations can cause cognitive overload, deviations from normal practice, lack of familiarity with the procedure and/or drugs, fatigue and communication deficits which can all contribute to an adverse outcome (Jones et al., 2018).

What can we do to minimise error?

Improve communication

Effective communication at every level is paramount in reducing error proliferation. Communication between the veterinary surgeon and the owner has long been identified as an important aspect of veterinary care; however, much less effort has been directed to the development of communication within the clinical team and the essential role of leadership (Oxtoby et al., 2015). It has been shown that communication failures have been associated with 43 percent of errors in operating theatres in medical practice (Gawande et al., 2003). It is vital that an atmosphere of open information exchange is achieved by empowering all team members to speak out (Jones et al., 2018). Again, this highlights the importance of teamwork, where the mental and physical problem-solving capabilities of a group can be maximised, such that the sum is greater than its parts (Pierre et al., 2011).

Keep good records

  • Cross-check medical records, the consent form and the proposed surgical intervention
  • Ensure that all relevant clinical information is stated on the anaesthetic record to facilitate appropriate decisions regarding anaesthetic-related care
  • Keep an accurate and dedicated anaesthetic record for every animal, no matter how short the intended procedure

Perform thorough clinical examinations

A thorough clinical examination underpins the provision of safe anaesthesia in all species.

Use surgical safety checklists

Surgical safety checklists have been routinely used in human medicine for more than 10 years. In veterinary medicine, the use of a checklist has gained in popularity over the last five years. The Association of Veterinary Anaesthetists (AVA) offers a freely downloadable checklist. There is no doubt that use of a checklist improves patient safety (Haynes et al., 2009). Veterinary studies have shown that checklists reduce the incidence (Cray et al., 2018) and severity of perioperative complications (Bergström et al., 2016).

In their simplest forms, checklists are an aide-memoire, encourage team synchronicity and most importantly increase communication between team members (Carne et al., 2012; Oxtoby and Mossop, 2016). Checklists can also improve specific outcomes such as airway safety (Hofmeister et al., 2014) and the consistency of antimicrobial prophylaxis (Menoud et al., 2018).

Effective checklist utilisation has faced challenges with compliance and universal uptake in veterinary practice. One of the challenges involves the adaptation of the checklist so that it can be used effectively in a specific practice environment (Menoud et al., 2018).

Check equipment prior to the start of each procedure

The surgical safety checklist prompts a series of equipment checks to ensure that correct functioning is confirmed prior to the start of each procedure. Equipment errors can be fatal and many are avoidable. For example, in a retrospective analysis of perioperative mortality in small animals, two canine fatalities were associated with a closed adjustable pressure limiting valve (Brodbelt et al., 2008).

Adhere to minimum monitoring recommendations

The AVA recommends that each patient should be monitored by a dedicated anaesthetist. Additional monitoring equipment including pulse oximetry, capnography and blood pressure should be available and utilised for every patient (AVA, 2021).

A retrospective study of feline perioperative fatalities found that pulse monitoring and pulse oximetry were associated with reduced odds of fatality (Brodbelt et al., 2007). Furthermore, since the recovery period represents a significant time of risk, extending monitoring to the post-operative period might aid in a further reduction in mortality rates (Brodbelt et al., 2008). Variable pitch tones and audible monitoring alarms can shorten the time of recognition of desaturation by the anaesthetist (Craven and McIndoe, 1999) and be more rapidly detected compared to visual alarms (Morris and Montano, 1996).

Close observation, accurate record keeping and vigilance on the part of the dedicated anaesthetist is the safest approach to monitoring general anaesthesia. Monitoring equipment can assist the dedicated anaesthetist but a comprehensive understanding of equipment function, benefits and shortfalls is essential to ensure the correct interpretation of the information yielded.

Protect against distraction

Noise level should be kept to a minimum to reduce distraction (Jones et al., 2018) and interference with the audibility of anaesthetic monitor alarms (Momtahan et al., 1993).

Avoid medication errors

Anaesthetic drug errors are commonly caused by slips and lapses, failure to revise a situation as new evidence emerges, mistakes, knowledge-based errors and deliberate violations (Glavin, 2010). Medication safety is universally regarded as one of the largest categories of safety problems.

There are many ways to reduce medication errors:

  • Label all syringes and infusion lines (Figure 1) – brightly coloured labels are particularly useful for controlled drugs (Figure 2). Double check the label on the syringe and/or medication bottle prior to administration
  • Cross-check with a colleague or textbook when calculating drug doses
  • Write down calculations and use a calculator to minimise errors
  • Organise pharmacy shelves to minimise accidental medication error. Ensure pharmacist communication with the whole team if the appearance, formulation, concentration or nature of a medication changes from the supplier
  • Be aware of drug bottles/labels which look alike and may be mixed up
  • Organise the workspace and anaesthetic tray to reduce medication error. For example, store induction agents separately from other drugs in the tray to reduce inadvertent premature administration
  • Perform accurate recording and audit of drug administration errors to ensure issues are addressed and repeated error is avoided

Practise emergency scenario preparedness

Emergency situations are by their nature uniquely challenging. Teamwork and preparedness may be optimised by regularly practising as a team for such events. In the event of a real emergency, these events can be rapidly reconstructed to provide facility, equipment, drug and knowledge readiness in the acutely ill animal. Most commonly, such scenarios focus on cardiovascular collapse.

Various guidelines have been formulated in the veterinary literature to facilitate emergency preparedness. The RECOVER initiative provides an evidence-based resource for cardiopulmonary cerebral resuscitation (CPR) in small animals (RECOVER, 2021). Published guidelines are also available for CPR in small animals and foals (Fletcher et al., 2012; Jokisalo and Corley, 2014).

Perform clinical audit

Clinical audits are a quality improvement process with the goal of continuously improving quality of patient care as assessed by explicit criteria (Rose et al., 2016). Performance of regular clinical audits is now encouraged by the Royal College of Veterinary Surgeons and is part of the Practice Standards Scheme. In the words of a Chief Medical Officer, “to err is human, to cover up is unforgivable and to fail to learn is inexcusable” (Feinmann, 2011).

Clinical audits are particularly valuable in the aftermath of error to try to prevent future events, particularly those described in human medicine as “never events”, which are serious incidents considered to be wholly preventable (Oxtoby and Mossop, 2016). Despite its potential to improve patient care, a systematic review in 2016 indicated that application and reporting of clinical audits in veterinary medicine is sporadic (Rose et al., 2016). Clinical audits can be applied to almost any topic and can be particularly useful in areas where significant risk exists. Clinical audits can also be applied more generally with the aim of identifying adverse events which occur on more than one occasion.

Hofmeister et al. (2014) performed an initial audit of anaesthesia patient safety which identified areas for improvement such as mis-injection, endotracheal intubation and machine checks. Changes were implemented and a follow-up audit showed a significant reduction in patient safety incidents. Furthermore, patient safety incident reporting can identify potential risks to the patient without it necessarily resulting in morbidity or mortality (McMillan, 2014).

Contribute to large scale perioperative reporting

Large scale retrospective studies have been instrumental in collating large amounts of information to identify anaesthesia-related risk factors and improve education (Johnston et al., 2002; Brodbelt et al., 2008).


Improving patient safety in veterinary anaesthesia has gained widespread attention in recent years. However, if safer anaesthetic systems are to be developed and adopted in a widespread fashion it will require a joint effort based on collaboration, joint experiences and a sound evidence base (McMillan, 2014). A patient safety orientated mindset should set in motion the improvements to which we should all aspire and help establish a patient safety culture within veterinary anaesthesia. A commitment to optimising patient safety by individuals as well as the whole veterinary team will help drive forward an improved safety culture in our profession.