Clinical Reasoning in Veterinary Practice. Группа авторов
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has 3+ glucosuria and no ketones in the urine.
Does this mean that diabetes mellitus explains all of the dog’s clinical signs? No – usually uncomplicated diabetes does not result in depression, anorexia and vomiting. There must be another reason for these clinical signs. Diabetic ketoacidosis might have been an explanation, but it has been ruled out by your urinalysis. Hence, you must look further for an explanation for the vomiting, anorexia and depression.
Example 2
An unwell dog (anorectic, vomiting and depressed) is found to have clinicopathological changes consistent with hyperadrenocorticism. Does this explain all of the dog’s clinical signs? No – dogs with uncomplicated hyperadrenocorticism are not metabolically unwell, so there must be some other explanation for the dog’s malaise that you will need to identify and resolve before definitive testing for hyperadrenocorticism is possible (because concurrent disease has a significant impact on dynamic adrenal testing).
Think pathophysiologically
Another essential element is to think pathophysiologically. Understanding physiology and pathophysiology is essential to understand medicine.
For example, an animal has profound hypokalaemia. Rather than trying to remember all of the diseases that may cause hypokalaemia, review how the body might lose potassium or fail to acquire it or even ‘use it up’. By getting into the habit of thinking in this manner, you can potentially diagnose disorders you may never have heard of (or that may never have been described before!). It will also stimulate you to seek more knowledge about the pathophysiology of disease processes, which will lead to a greater understanding of internal medicine and ultimately to a better retention of knowledge.
It may appear tedious at times!
You may feel at times that being asked to assess each individual’s specific problem is a tedious exercise when the diagnosis is obvious, because you think you recognise the pattern of clinical signs. In some, indeed many, cases, depending on your level of experience, this will be absolutely true, whereas in other cases, you will be misled. However, the most important point that we will try to get across is that if you don’t ‘practice’ this structured problem‐based approach on relatively simple clinical cases, when you are faced with the complex cases, which you may be feeling frustrated and stressed about at present, you will not be able to apply problem‐based principles and as such will be still left floundering as pattern recognition and/or going fishing fail you.
It is also important to recognise that pattern recognition is a process of thinking that doesn’t require explicit teaching – it happens naturally, whereas developing a robust structured inductive approach does require explicit articulation and practice of the steps involved.
It is useful to remember that medical diagnoses are often based on the ‘balance of probabilities’ rather than having to be proved ‘beyond reasonable doubt’. Striking the right balance between the diagnostic possibilities and judging what is important or likely and what is less important or less likely can be challenging and, of course, is very influenced by experience but also understanding and knowledge.
Ancillary benefits
The aim of a structured and thorough approach to diagnosis is to reach the answer as quickly as possible and to get the best value from your ‘diagnostic dollar/pathology pound/enabling euro’ – that is, not to waste the client’s money on unnecessary tests and procedures. An additional advantage of following this approach is that you should have a very good idea why you are advising doing blood tests or taking radiographs or prescribing a particular medication. And because you know why, you can explain your reasons to the client clearly, and they are much more likely to agree to follow your suggestions. Client compliance is positively influenced by the degree to which they understand the reasons for diagnostic or treatment recommendations.
You are also in a much better position to explain the implications of ‘normal results’ rather than being sent into a panic because you were hoping the blood tests would show something (‘because the dog looks really sick, so it must have an abnormal blood test! – but…its blood results are absolutely normal! – HELP! – what do I do now?’).
Time waster or time saver?
It is common when first faced with the process of problem‐based inductive clinical reasoning to feel that it is an academic exercise that there simply isn’t time to apply in the context of a busy clinic, 10–15‐minute consultation slots and the many conflicting demands on your time. However, if you are able to put in the hard work initially and if you discipline yourself to think in this way, it will become second nature, subconscious (thus you have reached unconscious competence) and certainly not as laborious as it may appear at the beginning.
In fact, acquisition of these problem‐solving skills will ultimately save time, as it will help you quickly eliminate extraneous background noise and focus on what is important for this patient and client. An analogy is the process of learning a new language. To do so, you initially need to learn some vocabulary and grammar (framework), but once you have a basic understanding and if you use the new language on a daily basis, further progression to fluency aka unconscious competence comes naturally. But without the basic framework and constant practice, fluency is an unfulfilled dream.
Comments from participants in courses based on this approach include:
‘I developed a more systemic approach to medicine, which saved a lot of time in a busy practice’.
‘It made me think more efficiently in a busy practice’.
Hopefully, this will be your experience too. As with all skills, it takes time to develop the knowledge base and mental discipline required for this form of clinical reasoning, but once developed, it will provide a firm base for the future and, most importantly, will not ‘go out of date’, no matter how many new diseases/disorders are discovered.
Figure 2.7 Clinical reasoning step‐by‐step: recap.
Key points
As a result of reading this chapter we hope that you appreciate that:
Problem‐based inductive clinical reasoning…
Is much more than just listing problems, then listing differentials for each problem (a common misconception about problem‐based medicine)
Has ‘rules’ that are easy to remember and can be applied to most clinical problems animals present with
Has a structured approach to clinical problems centred on four main steps (Figure 2.7) as follows:Define +/‐ refine the problemDefine and refine the systemDefine the location (where appropriate)Define the lesion
Provides an intellectual and visual framework to hang your knowledge on, allowing you to recognise and retrieve more easily the information you need
Reduces the need to remember a long list of differentials (see the first point)
Helps prevent getting trapped by a perceived ‘obvious’ diagnosis – it helps avoid diagnostic bias
Provides memory triggers to ensure an appropriate history is taken and a thorough clinical examination performed
Provides