Title: RVC Emergency Case Scenario - Jonnie

RVC Emergency Case Scenario - "Jonnie"

Welcome

Welcome to this Emergency Case Scenario from the Royal Veterinary College.

Throughout this scenario you will be taking on the role of the vet in charge of the case. You will be presented with clinical information, and ask to make clinical decisions. Feedback is given at each stage to allow you to understand which answers are wrong, or right, as the case may be. For some emergencies, even minor mistakes in decision making could prove fatal; rather than make you start from the beginning, this scenario will place you back at the most recent set of options for you to try again.

If you have any clinical questions about this scenario, please feel free to discuss them with any member of the ECC faculty!

Good luck!

Signalment

"Jonnie" is a 3 year old, female spayed medium (15Kg) crossbreed dog. She has presented to your practice for acute onset collapse while out exercising on a warm day.

Options

Q: 2. What would you like to do first?
- Obtain a full history
- Perform a full physical examination
- Perform a triage and major body systems assessment

History

You decide to obtain a full history from the client. Sadly, during the course of this history (specifically as Jonnie's owners were regaling you with the benefits of a raw diet), Jonnie became agonal and rapidly suffered a cardiopulmonary arrest.

In emergency patients stabilisation takes priority over obtaining a history. Sometimes you could ask a colleague (nurse or receptionist) to obtain a "bullet history" which includes the bare minimum data, such as pre-existing diseases or medications, and what has happened in the immediate run up to Jonnie being brough to the practice. Having someone else do this leaves you free to focus on Jonnie.

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Physical examination

You decide to perform a full physical examination. Sadly, whilst checking Jonnie's anal glands (because you never know!), she becomes agonal and suffers a cardiopulmonary arrest.

Emergency patients are often not stable enough to undergo a full physical examination. Instead full physical examination should wait until after initial stabilisation has been performed and you are confident they are stable enough to undergo the examination. This is particularly important in cats, as the stress of examination can often cause serioues deterioration in their condition.

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Triage and MBA

You opt to perform a triage and major body systems assessment.

Well done, this is the right option to choose here, as you don't currently know how stable the dog is. The triage and major body systems assessment will inform you of any immediate threat to life, which is going to important in deciding if emergency stabilisation is needed.

Click proceed to see the results of your triage and major body system assessment.

Triage and MBA findings

Credits: by tgreensmith (Author)

As you get to the waiting room to perform your triage you note that Jonnie is in lateral recumbency and does not seem to try and stand up. Her owner tells you she isn't able to walk and has vomited a few times so far today. Your triage is as follows:

- Cardiovascular - Heart rate 180bpm with pale pink mucous membranes a capillary refill time of 2 seconds. Femoral pulses are present but weaker than normal, and the dorsal pedal pulses are barely palpable. Pulses are synchronous with the heartbeat during auscultation. No murmur or arrhythmia is noted.
- Respiratory - Jonnie is panting with normal effort. Lung auscultation documents louder than normal bronchovesicular sounds, but you cosnider this to be normal as she is panting. Thoracic percussion is normal on both sides of the chest.
- Neurologic - Jonnie is obtunded.

Make a quick note of these values so you can refer back to them when you are asked further questions.

Missing?

Q: Is there something missing from your triage and major body systems assessment that is important?
- No
- Yes

No?

No? Owch, I'm afraid that's not right. This dog has acute onset collapse whilst exercising on a warm day. Heatstroke has to be high on your list, so a rectal temperature is mandatory.

Thankfully your nurse takes a rectal temperature on your behalf, it's normal at 37.2C, but you must remember to check rectal temperature, there is a good reason why it is a vital sign!

Yes

Yes! You're spot on. Where is the rectal temperature? This dog collapsed during exercise on a hot day, failing to get a rectal temperature could have fatal consequences.

Your nurse obtains a rectal temperature for you and thankfully it's normal at 37.2C

Options

Q: 4. You take Jonnie into the prep room after obtaining permission for 'emergency stabilisation' from his owner. What would you like to do next?
- Place an intravenous catheter
- Give 30ml/kg of balanced isotonic crystalloids subcutaneously
- Rub some glucose on Jonnie's gums

Subcutaneous fluids

I'm afraid this is not a good choice.

Fluids might be a good option (we don't have enough information to be sure yet), but giving fluids under the skin is only really useful to help reduce ongoing dehydration. Subcutaneous fluids can't be used to treat shock, and in patients who are emergencies it is very likely they won't absorb drugs and fluids from the subcutnaeous space very well. If we then consider the volume in this option, 30ml/kg is a very large amount, even in a totally healthy patient this would take many hours to be absorbed.

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Oral glucose

Sadly this is not a good option.

We don't have any proof that Jonnie needs glucose at the moment, and if she did need glucose then it would be better to give this intravenously. Oral glucose is reserved for owners to perform at home if their diabetic dog/cat has signs of hypoglycaemia after insulin administration.

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Intravenous catheter placement

Well done, this is spot on.

Placing an IV catheter will be vital for stabilisation, but it will also allow us to pull some blood directly from the catheter for our minimum database.

IV catheter and minimum database

You have difficulty placing the IV due to the poor quality of the veins, they just won't raise! Thankfully your persistence pays off and you manage to get a catheter in and obtain a small amount of blood.

Your minimum database shows

- PCV 55% [Reference 35-55%] and total solids 50g/L [Reference 55-70g/L]
- Sodium 138mmol/L [Reference 142-151mmol/L]
- Potassium 5.2mmol/L [Reference 3.8-4.8mmol/L]
- Glucose 2.2mmol/L [Reference 3.8-6.4mmol/L]

Twitching

Q: Jonnie starts twitching slighty and is now un-responsive. What will you do?
- Glucose. 0.5-1ml/kg IV of a 50% solution, and diluted with the same volume of 0.9% sodium chloride
- Glucogel smeared on the lips and gums
- I think it might be time to say goodbye (That is not the right attitude!: If you give up this easily, how did you make it to clinical years of vet school??? Jonnie has a completely treatable disease, this is not the time to give up!)

Glucogel

Glucogel on the lips and gums? No. That's not a great move, but it could be ok as a last resort if you don't have IV glucose available.

Oral and transmucosal glucose will be a variable dose, with variable absorption compared to IV glucose. Added to that, we have a neurologically abnormal patient who is deteriorating, putting anything in the mouth risks it being aspirated.

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IV glucose

Yep, that's right.

IV allows us to give a defined dose, without worrying about the variable absorption we might otherwise get. It also means we avoid putting sticky syrup in the mouth of a patient at high risk for aspiration!

Options

Q: 6. Jonnie's twitching stops and she seems slightly more awake. What should you do next?
- Intravenous fluid bolus of 20ml/kg 0.9% NaCl
- Give a further dose of 0.5-1ml/kg intravenous glucose
- Point of care ultrasound of the chest and abdomen

Fluids

I'm afraid this isn't the best option available to you. Fluids themselves is probably not a terrible idea, but we don't know yet why Jonnie is in shock, and some shock types will be made worse with fluids.

When bolusing a patient with fluids, it's always worth remembering you should use a fluid that has a sodium content as close as possible to the patient's sodium value. This helps to reduce fluid shifts that might otherwise occur. Jonnie's sodium is 138mmol/L, 0.9% saline has a sodium of 154mmol/L, while Hartmanns and compound sodium lactate both have sodium concentrations closest to Jonnie's serum level and so should be used for fluid boluses in this situation.

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More glucose

More glucose is not the best option here. There are some cases where a single bolus of IV glucose might not be enough, but before giving more glucose we should recheck the patient's glucose level to make sure we aren't going to cause hyperglycaemias which has its own problems.

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POCUS

Point-of-care ultrasound (also known as POCUS) is a great choice. If you didn't have an ultrasound you could be forgiven for an empiric fluid bolus given the circumstances, but is you have access to an ultrasound machine then doing a POCUS first is ideal.

POCUS will allow us to rule in or out several important differentials, and will help guide our ongoing stabilisation. It takes an experienced operator under 5 minutes to perform, and so can be done rapidly with emergency patients.

Click proceed to see the POCUS scans for this patient, and assess the images as you would do if the animal was in front of you. Your assessment will be needed to determine some of the next few answers.

POCUS VIDEO when private server available

POCUS

Q: Are there any abnormalities on POCUS?
- Yes
- No

No

Correct, there are not abnormalities noted on the POCUS. The left atrium is normal size and cardiac contractility is subjectively normal. There is no pericardial effusion, and no obvious changes to the lung parenchyma. The abodminal POCUS does not demonstrate any evidence of peritoneal fluid either.

Yes

Sadly that's not true. The POCUS doesn't show any abnormalities at all.

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Q: 8. What type of shock is the patient most likely to be in?
- Cardiogenic
- Maldistributive
- Obstructive
- Hypovlaemic

Cardiogenic

I'm afraid cardiogenic shock is not correct. The POCUS doesn't reveal any evidence of congestive heart failure (often we would expect a large left atrium, potentially with evidence of pulmonary oedema which can show as "B-lines") or systolic dysfunction (which would manifest as poor contractility). Triage didn't reveal any evidence of an arrhythmia either. With all of these being absent, we have no supportive evidence for cardiogenic shock.

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Maldistributive shock

I'm afraid this isn't the best option either. This dog could be in maldistributive shock, but one of the hallmarks of that is that it causes relative hypovolaemia, most commonly by causing vasodilation. If Jonnie were vasodilated to such a severe degree to lead to the dramatic signs we are seeing, there should be some evidence of vasodilation, such as congested or injected mucous membranes.

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Obstructive

Obstructive shock isn't correct. The most common causes of obstructive shock are very unlikely in Jonnie, as we have no evidence of pericardial effusion on thoracic POCUS, and no clinical signs suggestive of a GDV.

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Hypovolaemic

Hypovolaemic is the correct option. We have clear evidence of hypovolaemia (tachycardia, a long capillary refill time, poor pulses) and historical evidence of volume loss (vomiting). Other types of shock have either been ruled out (such as cardiogenic due to our normal POCUS), or do not fit our clinical findings so far (such as maldistributive and obstructive shock)

Options

Q: 9. Having confirmed we have hypovolaemic shock, what is your next step?
- Obtain a non-invasive blood pressure
- Provide an intravenous crystalloid bolus
- Give intravenous dexamethasone (0.3mg/kg)

NIBP

This isn't the best choice. While the information derived from a blood pressure may be useful, the dogs cardiovascular and clinical condition are supportive of decompensated hypovolaemic shock. In decompensated shock the blood pressure will be low, and we expect this to be the case. Having a baseline would be useful, but struggling to obtain a blood pressure at the expense of starting intravenous fluid resuscitation isn't as wise. If you have a competent person who can try and get a blood pressure while you begin giving fluids, then that would be the ideal situation.

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IV fluids

Fluids is absolutely the right choice. Although a blood pressure would be a useful number to know, we expect it to be low as the dog is in decompensated shock. Struggling to obtain a bood pressure at the expense of giving fluids isn't wise, but if you had an extra pair of hands who could get the blood pressure while you give the fluids then that would be ideal.

Steroids

Sorry but that's not right. There are no indications for steroids at this point in time, and there are numerous side effects that could be damaging. Let's hold off until we know what is wrong with the patient.

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Options

Q: 10. Which of the following would you use for your bolus? Pay attention to the type of fluid and its dose!
- 5ml/kg of synthetic colloid suspended in isotonic crystalloid
- 15-20ml/kg of a balanced isotonic crystalloid (e.g. Hartmmans, Ringers or Compound Sodium Lactate)
- 30ml/kg of 7.5% NaCl
- 7.5ml/kg of 0.9% NaCl

15-20ml/kg of balanced isotonic crystalloid

That's a great choice.

A balanced isotonic crystalloid is ideal in this patient to restore vascular volume. One thing to bear in mind when giving fluids boluses to patients with abnormal sodium, is that giving a fluid with a very different sodium can be damaging (as it can promote shift of fluid either into or out of the vascular tree). Jonnie has mild hyponatraemia (138mmol/L) and so while Hartmanns, Ringers and compaound sodium lactate would all be idea, 0.9% NaCl could be used too. If Jonnies sodium was much lower (say under 130mmol/L), then even saline would risk being damaging, and if her sodium was over 160mmol/L then using anything other than 0.9% saline could be dangerous.

Always remember to consider this when bolusing patients with abnormal sodium, if in doubt give 0.9% saline to those with hypernaetraemia, and Hartmanns or similar to those with hyponatraemia

5ml/kg of synthetic colloid

A 5ml/kg synthetic colloid bolus could be used in this case, but it would't be our first choice normally.

Synthetic colloids have had a turbulent time recently, with difficulty in obtaining them as they have been proven to increase the risk of death and renal injury in several populations of patients in people. Synthetic colloids also have other side effects cinluding coagulopathy and tissue accumulation, and have not been shown to confer any benefit over the use of crystalloids in large studies. As synthetic colloids are more expensive than crystalloids, and still a little tricky to get hold of, we would probably choose something else until we know more about our patient.

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