or expert opinion, should be qualified, and the inherent uncertainty of the supporting evidence must be disclosed to clients. Recommendations based on more reliable evidence, such as systematic reviews or clinical practice guidelines, can be presented with much greater confidence.
Figure 2.1.1 An evidence pyramid illustrating the variable reliability and risk of bias of different types of scientific evidence.
Clinicians must always use their individual judgment in drawing conclusions from scientific evidence and applying these to specific patients. However, the hierarchy of evidence makes it easier for veterinarians to identify the reliability of specific types of evidence and of conclusions based on this evidence and to then communicate the degree of uncertainty to pet owners.
Charlie is a 4‐year‐old neutered male Cavalier King Charles spaniel. His owner is seeking your opinion because another veterinarian recently told her Charlie has a heart murmur. The owner was told that because Charlie is young and has no clinical issues, there is no need to do any tests or start any treatment. However, her breeder has told her that Charlie should be on a medication called “enalapril.”
You are aware of the breed predisposition for mitral valve disease (MVD) in Cavaliers, and you tell the owner that this is the most likely diagnosis based on Charlie's signalment and physical exam findings. You have also recently reviewed the American College of Veterinary Internal Medicine guidelines for diagnosis of MVD [1], and you explain that Charlie has stage B MVD, meaning he has a murmur but no clinical signs.
You explain that while enalapril was once commonly recommended for dogs with preclinical MVD based on low‐level evidence (pathophysiological reasoning and clinical experience), higher quality evidence (clinical trials) [2, 3] has since shown that it does not delay the onset of congestive heart failure (CHF), so you recommend against this medication.
In association with another case, you recently investigated whether there are any useful treatments for dogs with stage B MVD. You discovered the EPIC study, a high‐quality clinical trial investigating the use of pimobendan in dogs with MVD [4]. This trial included a lot of Cavaliers, so you believe the results are applicable to Charlie. You tell the owner that this study found a dramatic delay in the onset of CHF in dogs using pimobendan if they were in stage B2 MVD, meaning they had enlarged hearts. You explain that you could stage Charlie using radiographs, but the EPIC study suggested measurements from an echocardiogram are more reliable, so you recommend this test.
The owner is impressed with your detailed scientific knowledge and happy to have something she can do to keep Charlie healthy. You arrange an echocardiogram and agree to manage Charlie's MVD based on the results.
EBVM is a comprehensive system for producing and disseminating reliable scientific evidence and for integrating this evidence into clinical decision making.
EBVM methods make identifying, finding, and using needed information easier for veterinarians.
Integrating research evidence with clinical experience and the needs and resources of owners helps reduce medical error and supports more proactive, effective pet‐specific care.
EBVM also facilitates our ethical obligations to provide the most effective care for patients and to support informed consent for clients by providing the most accurate information and a clear assessment of relevant uncertainty.
EBVM helps veterinarians provide better care and better client communication with greater confidence and less time and effort.
References
1 1 Atkins, C., Bonagura, J., Ettinger, S. et al. (2009). Guidelines for the diagnosis and treatment of canine chronic valvular heart disease. Journal of Veterinary Internal Medicine 23 (6): 1142–1150.
2 2 Atkins, C.E., Keene, B.W., Brown, W.A. et al. (2007). Results of the veterinary enalapril trial to prove reduction in onset of heart failure in dogs chronically treated with enalapril alone for compensated, naturally occurring mitral valve insufficiency. Journal of the American Veterinary Medical Association 231: 1061–1069.
3 3 Kvart, C., Haggstrom, J., Pedersen, H.D. et al. (2002). Efficacy of enalapril for prevention of congestive heart failure in dogs with myxomatous valve disease and asymptomatic mitral regurgitation. Journal of Veterinary Internal Medicine 16: 80–88.
4 4 Boswood, A., Häggström, J., Gordon, S.G. et al. (2016). Effect of pimobendan in dogs with preclinical myxomatous mitral valve disease and cardiomegaly: the EPIC study – a randomized clinical trial. Journal of Veterinary Internal Medicine 30 (6): 1765–1779.
Recommended Reading
1 Best BETs for Vets – A collection of CATs for veterinary species. http://bestbetsforvets.org
2 Cockroft, P. and Holmes, M. (2003). Handbook of Evidence‐Based Veterinary Medicine, 210. Oxford: Blackwell.
3 McKenzie, B.A. (2014). Veterinary clinical decision‐making: cognitive biases, external constraints, and strategies for improvement. Journal of the American Veterinary Medical Association 244 (3): 271–276.
4 McKenzie, B.A. (2014). Evidence‐based veterinary medicine: what is it and why does it matter? Equine Veterinary Education 26 (9): 451–452.
5 Schmidt, P.L. (ed.) (2007). Evidence‐based veterinary medicine. Veterinary Clinics of North America: Small Animal Practice 37 (3): 409–417.
6 VetSRev – A database of all systematic reviews in veterinary medicine. www.nottingham.ac.uk/cevm/evidence‐synthesis/systematic‐review/vetsrev.aspx
2.2 The Role of Incremental Care
David Haworth, DVM, PhD
Vidium Animal Health, Phoenix, AZ, USA
2.2.1 Summary
Veterinary medicine has made incredible strides regarding the sophistication of care that can be provided by veterinarians in practice. The training of veterinary students by board‐certified specialists, usually in tertiary care facilities, has had numerous advantages but has also resulted in generations of veterinarians trained to only provide the very best options, which are usually also the most expensive. When other options are given, it is only at the behest of the client, and is clearly considered a compromise.
There
