58 terms

Internal/meds- Metabolic collapse/hypoadrenocorticism

Common persistent or episodic, many possible causes - cause often elusive.
What are some causes of metabolic collapse?
1) diabetic ketoacidosis
2) hypoglycaemia
3) hyper/hypo kalaemia
4) hyper/ hypo calcaemia
5) hyper/hypo natraemia
6) hepatic encephalopathy
7) phaeochronmocytoma- rare
8) hyperviscousity syndrome-rare
9) thyrotoxicosis- rare
10) myxoedema coma- rare
What are the initial tests done if collapse?
1) glucose
2) calcium
3) electrolytes
4) this is in addition to history and clinical exam
Syncope is?
Acute episode of flaccid collapse, cardiovascular.
Fit = seizure is?
Acute, central, tonic - clonic etc, neurological (primary or secondary metabolic)
Falling over = weakness is?
Generalised, metabolic, haematological orthopaedic, neurological.
What should be normal on a clinical exam before moving onto laboratory tests?
Evidence of cardiac and other diseases e.g. pallor, cyanosis, dyspnoea, distended veins, resp noise/crackles, arrhythmias, muffled thoracic sounds.
What is the most common cause of metabolic collapse?
Decreased potassium
Hypokalaemia is very common and often caused by?
1) intersitial loss: vomiting, diarrhoea
2) CRF cats
3) ch. diuresis (+ anorexia)
4) often a combination!
What are some complications of metabolic collapse?
1) pancreatitis
2) acute renal failure
3) urinary tract infections
4) bacteraemia/septicaemia
5) gastro intestinal haemorrhage
6) pulmonary thromboemboslim
7) disseminated intravascular coagulation
What is the most common complication of metabolic collapse in a dog?
On clinical exam - monitor?
1) temperature
2) pule
3) respiration
4) MMS
5) CRT
6) urine output
There are only 2 reasons to stop monitoring a patient?
1) recovery
2) death
What is the first treatment?
Fluid therapy
How much fluid should be given in the first hour?
20% of requirements
What do you add up for fluids in the first 24 hours?
1) % dehydration
2) continuing losses
3) maintenance
What is the key to success in hypokalaemia?
Give a lot of fluids/ aggressive fluid therapy early on.
What are the main CS of Addison's?
1) inappetance
2) depression
3) anorexia
4) vomiting
When does immune mediated destruction of the adrenals normally occur?
1-5 year old dogs.
What is the main problem with hyperadrenocorticism?
The loss of aldosterone. it acts on the salt balance so that the urine salt balance causes loss of fluid and dehydration. There is therefore an increase of angiotensin II in the blood with Addison's because the body is trying to correct the dehydration, but its not working on the adrenals cos they are destroyed.
Hypoadrenocoticism is mostly?
An immune mediated destruction
Hypoadrenocoticism immune mediated destruction occurs in what age and breed?
1) young to middle aged 1-5 year old, often females
2) Standard Poodles, Bearded Collies, Rottweiler's, West Highland White Terriers, German Shorthaired Pointers.
What are the 3 types of hypoadrenocoticism?
1) immune mediated destruction
2) mitotane/trilostane induced (adrenal necrosis/suppression)
3) other: haemorrhages, infarction, infection, tumour
There is variable presentation of hypoadrenocoticism, what CS would you see?
1) Chronic often respond to non specific therapy
2) neurological : depression, weakness
3) gastro-intestinal signs: iappetance, vomiting/ diarrhoea
4) metabolic: failure to thrive, weight loss, mild PU/PD
What are the clinical findings with severe hypoadrenocoticism?
1) severe dehydration
2) anorexia
3) vomiting
4) collapse
5) bradycardia
6) haemorrhagic gastroenteritis
What changes can be seen on an ECG with hypoadrenocoticism?
No P waves, and spiked T waves- if significantly dehydrates and hyperkalaemic.
What are some possible complications of hypoadrenocoticism?
1) acute renal failure
2) gastro intestinal haemorrhage
3) pancreatitis
4) pulmonary thromboembolism
5) disseminated intravascular coagulation
What are some differential diagnosis to Addison's/ hypoadrenocoticism?
1) Inflammatory bowed disease - vomiting/diarrhoea
2) renal failure - PU/PD
3) Neoplasia - weight loss
4) pancreatitis- abdominal pain
5) H.G.E, Bradycardia, episodic collapse, lethargy
Haematology with hypoadrenocoticism might show what?
Anaemia: GI losses, Bone marrow suppression, IMHA, dehydration masks severity of this. 70% of cases are anaemic.
What does a reversed stress leucogram refer to?
Dogs that is ill will normally have a stressed leucogram= high neutrophils, eosinophils and lymphocytes low. But in Addison's it's the opposite- low neutrophils., and higher eosinophils and lymphocytes (most dogs are normal).
What kind of biochem results can you expect in Addison's?
Sodium decreased, Potassium increased, K:NA radio.
What are some causes of high potassium and low sodium?
1) Hyperkalaemia: RBC lysis, failure to excrete
2) Hyponatraemia (metabolic condition) over hydration and massive loss
What is the sodium: potassium ratio in a dog with Addison's?
Less than 20
Is sodium : potassium ratio a diagnostic on its own?
What does hypoadrenocorticism and renal failure have in common?
1) acute episode after periodic illness
2) thin, dehydrated, may have collapsed
3) renal azotaemia (increased urea/creatinine) USG: 1.007-1.030.
4) high potassium
5) low sodium
What are the differences between renal failure and hypoadrenocoticism?
1) hAC: NA very decreased, K 90%, ca increased. USG: >1,008. no stress wbc, anaemia
2) CRF: USG: 1.008-1.002, Stress wbc, anaemia, no na or K
3) ARF: na decreased, k increased, USG: >1.030, stress wbc, no anaemia
What test can you use to diagnose Addison's?
1) ACTH stimulation test before starting therapy - no response its Addison's.
2) Could also use cortisol but cannot distinguish primary hAC from iatogenic HAC or recent steroid admin
3) aldosterone: same as cortisol
If the ACTH stimulation test come back increased its?
Stress, HAC- Cushings
How do you tx Addison's?
1) initially aggressive fluid therapy
2) if acute: hypovolaemia, sodium deficit and hyperkalaemia.
3) if chronic: minaralocoricoid replacement, glucocorticoid replacement and dietary changes
Calculate this: total fluid replacement for a dog with 10% dehydration?
2kg = 2 litres +
20 kg x 50 ml /24h = 1000 ml =
3 litter in 24 hours + any additional losses
What is maintenance fluid per day?
What fluids do you use to treat hyperkalaemia?
Saline. IV if possible. 20-60ml/kg/h for 2 hours then 4ml/kg/h.
If you don't have saline what can you give to treat hyperkalaemia?
Calcium gluconate
What is a short term treatment for Addison's?
Hydrocortisone sodium succinate. Mineralocorticoid + glucocorticoid (if don't have use methylprednisolone/dexamethasone)
What do you have to monitor during acute phase Addison's?
1) Temp
2) pulse
3) RR
4) MMM
5) CRT
6) urine output
7) Glucose
8) calcium
9) electrolytes
10) PCV
11) protein
What do you give for long term treatment of Addison's?
Fludrocortisone (UK) or DOCP (desoxycortisone puvilate -USA). If stressed: prednisolone. DOCP (always prednisolone).
What are the two growth hormone disorders?
1) acromegaly
2) dwarfism
Is there acromegaly in dogs?
Yes: large dogs.
Is there acromegaly in cats?
They can acquire it by GH releasing tumour mostly of pituitary gland.
What GH tumour is most common in cats?
Pituitary gland tumour
Acromegaly in dogs are related to GH released from?
Progesterone induced secretion from mammary gland - into milk and info foetus.
What are some signs of acromegaly in cats?
Increased soft tissue mass: hepatomegaly, thickened skin, diates mellitus. Neurological signs: depression, gradual changes.
What causes dwarfism and GH deficiency?
Congenital pituitary lesion, dogs and very rare acts.
Congenital panhypopituitarism will show sings of?
1) proportionate dwarfism
2) juvenile mentality
3) coat changes
4) repro dysfunction
Dwarfism is inherited in ?
GSD, Gorelian Beer dogs.
What can you use to measure GH?
Insulin like GF-1.!!!!!
The great pretender refers to?
Hypoadrenocorticism because it can look like a lot of other things.
How do you measure GH in acromegaly/dwarfism?
IGH-1 concentration.