Clinical Reasoning: Logical Approach to a Case

Question 1

1. What is clinical reasoning?

Answer 1

1. Thinking and decision-making processes associated with clinical practice.
   Thinking about something in a logical and sensible.

Question 2

What factors come into veterinary professional reasoning?

Answer 2

Client
Business
Human-animal bond
Public health and society needs.
Professional code of conduct.
Local regs
Clinical reasoning available evidence.
Patient welfare.
Colleagues
Self

Question 3

1. Absolute basic requirements to be a good clinician.
2. Why is clinical reasoning important?

Answer 3

1. Someone who is knowledgeable.
   Good decision maker.
2. In human med, has been estimated that a wrong diagnosis is made 10-15% of the time.
   Majority of diagnostic errors are errors in reasoning i.e. when the available data has not been synthesised correctly.

Question 4

Very basic framework for approaching a case.

Answer 4

Signalment.
Presenting complaint.
History.
Clinical exam.
Problem list.
Differential diagnoses.
Diagnostic tests.
Diagnostic results.
Final diagnosis.
Treatment plan.
Prognosis.
** A process of narrowing down possibilities.
** Many cases involve needing to loop back up framework.

Question 5

1. What is signalment?
   – Included in horse signalment?
   – Included in farm animal signalment?
2. Why is signalment important?

Answer 5

1. Age, breed, sex (neuter status).
   – Use e.g. racing, eventing.
   – Herd info.
2. Aspects of signalment may be highly relevant in helping establish a diagnosis due to predisposition.
   Can influence treatment or prognosis.

Question 6

1. What is a presenting complaint?

Answer 6

1. Main reason the owner brought the animal to the vets.

Question 7

1. What to expect when taking a history from an owner.
   – How can this be helped?
2. Vet’s responsibility in taking history?

Answer 7

1. Info to be given in a manner that is not ordered or concise, jumping back and forth with their info. Could mean lots of key points missed out and lots of irrelevant info included.
   – By being systematic in the questions that you ask.
2. To ask clear, understandable and pertinent Qs in a structured and methodical way.

Question 8

1. Things to gather info on when taking history?
2. Why would you need to be able to summarise the history.

Answer 8

1. Relevant management.
   Background.
   Previous medical history.
   Details of current condition.
2. Rounds.
   Discuss with colleague.
   Make case notes.

Question 9

Options for CE?

Answer 9

Can perform basic CE (head to tail).
Or can perform a more specific exam of an anatomical area or organ system based on info gathered from history and basic CE.

Question 10

1. What is the consequence of the history-taking and the CE not being done well?

Answer 10

1. All the rest will be based on incomplete or inaccurate info and can lead to mistakes.

Question 11

1. What is classed as a problem when writing a problem list?
2. Considerations when writing a problem list.

Answer 11

1. Anything that is physiologically or anatomically abnormal that may require health care management e.g. colic, icterus, tachycardia, inappetance.
2. Being clear on how things are defined in the problem list.
   Whether there is another clinical sign with which the problem could be confused.

Question 12

Steps of making a problem list.

Answer 12

• Write what is said by owner and what can be seen on CE.
• Redefine into vet terms.
• Condense down as some presentations and clinical signs can represent the same thing e.g. tacky MMs and skin tenting represent dehydration.
• Prioritise the problems. i.e. in terms of what you want to treat first / what seems most useful to help diagnosis e.g. most specific findings with quite clear and defined diagnostic pathways.

Question 13

In what cases may you need to make a treatment plan before gaining a diagnosis?

Answer 13

In critical cases where the animal requires urgent treatment to manage its condition while waiting for a diagnosis.

Question 14

1. What are differential diagnoses?
2. Different ways that differentials can be pursued?
3. What may come with experience when making a differentials list?
4. What can be done in the early stages of practice?

Answer 14

1. A list of all the possible diagnoses that could explain what is wrong with an animal.
2. Stopping at anatomical or functional level.
   Or going further to an aetiological or a histopathological level.
3. Immediate consideration of feasible differentials based on the problem list as a whole.
4. Using a diagnostic framework to help think carefully about which differentials can be discounted.

Question 15

1. Types of differential diagnosis frameworks.

Answer 15

1. Organ system framework.
   Anatomic region framework.
   Physiologic mechanism framework.
   Mixed framework.
   Other framework.
   Causes (mnemonic) framework.

Question 16

Example of systems framework.

Answer 16

Diarrhoea – GI and non-GI.
GI – large and small intestines.
Non-GI – Pancreas, liver, renal, endocrine, miscellaneous.
Small intestine conditions.
Large intestine conditions.
And non-GI conditions etc.

Question 17

Anatomic framework example.

Answer 17

Lameness in carpal region of horse.
Can be caused by soft tissue pathology, bone pathology, joint pathology, periarticular pathology.
Then build up a list of causes that can be linked to these pathology types.

Question 18

Physiological framework example.

Answer 18

Anaemia.
Is it regenerative or non-regenerative.
Regenerative could be haemorrhage or haemolysis.
Non-regenerative could be Primary bone marrow disease or extra bone marrow disease.
Then consider all conditions linked to these possibilities.

Question 19

Other framework example.

Answer 19

Nasal discharge.
Is it bloody (epistaxis)?
Purulent?
Mucoid?
And consider conditions associated with these types of discharge.
For horse, has it happened in exercise or rest?

Question 20

Causes (mnemonic) framework.
1. VITAMINCDE mnemonic?
2. GINANDTONIC mnemonic?

Answer 20

1. Vascular, Inflammatory/Infectious, Traumatic/Toxic, Autoimmune, Metabolic, Iatrogenic/Idiopathic, Neoplastic, Congenital, Degenerative, Endocrine.
2. Genetic, Infection/Inflammation, Neuro, Autoimmune, Nutritional, Developmental/Degenerative, Trauma, h(Ormonal), Neoplastic, Iatrogenic/Idiopathic, Cardiovascular/Chemical and toxic.

Question 21

What must be done while a full differentials list has been assembled?

Answer 21

Narrow down the list of differentials thinking about each condition and ruling in or out based on patient/case. – analytical/deductive reasoning.
Then order the list of differentials based on the likelihood or probability of each differential.

Question 22

1. What is a zebra diagnosis?
2. Why are students more likely to make these types of diagnoses?

Answer 22

1. Medical slang term for arriving at an exotic medical diagnosis when a more commonplace explanation is more likely.
   ‘When you hear hoofbeats, think of horses not zebras’ as horses are common in UK while zebras are relatively rare.
2. The striking and the novel stay longer in the mind.

Question 23

1. What does Sutton’s law state?

Answer 23

1. You should first consider the obvious when diagnosing, suggesting that you should first conduct those tests which confirm (or rule out) the most likely diagnosis.
   More likely to obtain a quicker diagnosis, and hence treatment, when doing this. This also helps to minimise unnecessary costs.

Question 24

Other considerations when deciding the order of diagnostic tests.

Answer 24

• Costs of diagnostic tests.
• Availability and risk/invasiveness of diagnostic tests.
• Accuracy of diagnostic tests.

Question 25

1. What percentage of diagnoses are made from history and clinical exam?
2. What can often happen when the diagnostic results are gained?

Answer 25

1. 80%
2. The problem list and differentials list can become even longer due to findings that were not expected or were not known so have to keep working through the framework.

Question 26

What is a final diagnosis?

Answer 26

The diagnosis you consider most likely after all the data has been collected, analysed, and subjected to logical thought.
Important to go back to problem list and ensure every that each problem on the list can be explained by this diagnosis. If not, then there is more than one disease process.

Question 27

1. Therapy types that may be included in the treatment plan.

Answer 27

1. Specific (e.g. bronchodilators for acute asthma)
   Supportive (e.g. IV fluids for acute colitis)
   Symptomatic (e.g. analgesics for colic)

Question 28

Considerations when making a treatment plan.

Answer 28

The best possible treatment for the condition / patient / case – based on individual clinical expertise and best available evidence from systematic research.
Real life factors – Owners’ wishes, finances, resources in practice etc.

Question 29

What do owners tend to care most about?

Answer 29

Prognosis – what to expect from the disease that has been diagnosed.

Question 30

Give examples where the process of working through a case may not work in the way previously illustrated.

Answer 30

• Where there is an emergency and the patient is in critical condition, you may need to provide emergency treatment before even being able to take a complete history.
• Where there are financial constraints and diagnostic tests cannot be paid for. May have guess and assume the most likely cause of symptoms and try to start treatment based on that and see if improvements are made.
• Pattern recognition may eliminate steps and mean you skip straight from differentials to treatment with no need for testing.

Question 31

The 2 types of reasoning.

Answer 31

• Pattern recognition is a process of thinking that does not require explicit teaching – happens naturally (type 1). Faster and based on intuition and previous experiences. Can be problematic and lead to errors.
• Developing a robust structured analytical approach requires explicit articulation and practice of the steps involved. Slow and effortful. Better for complex issues requiring more conscious intentional thinking and means less errors are made (type 2).

Question 32

1. What is availability bias?
   – How can novice clinicians avoid this?
2. What is recency bias?
3. What is confirmation bias?
4. What is premature closure?

Answer 32

1. Giving priority to the first thought that comes to mind.
   – Carefully consider decisions and gain advice and guidance from more experienced clinicians.
2. The tendency to give weight to events that happened recently.
3. When we gather info selectively or interpret it in a way to support our favoured conclusion while ignoring alternatives. – cresting a case for why you are right.
4. The tendency to end the decision making process early and accept a diagnosis even though it has not been completely explored and verified.

Question 33

How can we control our biases?

Answer 33

• Develop awareness of different types of biases through education of biases.
• Check points in clinical work to ensure we recognise signs of bias before they do damage.
• Systematic reflection – taking a moment after each step to quickly ask themselves what they are thinking in that moment and to consider alternatives that do not come immediately to mind.
  – reflection in action is reflecting while doing.
  – reflection on action is reflecting after doing.