autonomic nerves and kidney/liver under GA (Vet nursing Q.)

Re: autonomic nerves and kidney/liver under GA (Vet nursing Q.)

Evelyn Barbour-Hill — Tue, 16 Jun 2015 17:48:39 GMT

[quote user="Beats"]

http://cdn.cityandguilds.com/ProductDocuments/Land_Based_Services/Animal_Management/7457/7457_Level_3/Assessment_materials/7457_Veterinary_Nursing_sample_questions_v3.pdf

HEALTH WARNING: Under no circumstances are you to attempt question 7!

[/quote]

Q. 23. None of these! The notable word being "essential".

Q. 27. Yer wot? That's a humdinger. I'm sure it's important.

Re: autonomic nerves and kidney/liver under GA (Vet nursing Q.)

Beats — Tue, 16 Jun 2015 16:17:52 GMT

[quote user="Anthony Todd"]necessary knowledge of a RVN?[/quote]

I hope no-one shows you the sample questions!

I don't think I would pass... but thankfully I don't have to

Poor student though, exam tomorrow...

_____________________________________________________________________________

http://cdn.cityandguilds.com/ProductDocuments/Land_Based_Services/Animal_Management/7457/7457_Level_3/Assessment_materials/7457_Veterinary_Nursing_sample_questions_v3.pdf

HEALTH WARNING: Under no circumstances are you to attempt question 7!

Re: autonomic nerves and kidney/liver under GA (Vet nursing Q.)

Richard Carter — Tue, 16 Jun 2015 09:12:01 GMT

oooo - very impressive - I was vaguely aware that my nurse knows more about the autonomic system than I do

Re: autonomic nerves and kidney/liver under GA (Vet nursing Q.)

Anthony Todd — Tue, 16 Jun 2015 07:29:22 GMT

[quote user="Beats"]vet nursing student asked me about this in her syllabus [/quote]

Doesn't anyone else think this is perhaps a another great example of a syllabus which is way removed from the function and necessary knowledge of a RVN?

Re: autonomic nerves and kidney/liver under GA (Vet nursing Q.)

Beats — Mon, 15 Jun 2015 20:40:08 GMT

Thanks for suggestions!

I wasn't sure if there was a key fundamental that was being gotten at or something - it was the way it says: "especially renal and hepatic perfusion and function" made me think that there might be some important bit unique to these that was to be emphasised?

I explained that anything affecting cardiac output or blood pressure generally would affect tissue perfusion including liver and kidneys, and went through the basics of effects on alpha-1 and alpha-2 adrenoreceptors on blood vessels, as well as beta-receptors and vagally-induced changes on heart.

I wasn't confident beyond that...

Dr Google provided various info on autonomic recpetors and effects in kidneys/renal-vessels (less so w.r.t. liver / portal vein), but none of it was consistently present in discussions of clinical effects of anaesthetic agents so I was left wondering what the key info for a vet nurse was to be?

Here's the receptors in kidney and liver re function according to p.352 of Miller's Anesthesia

Kidney: Renin secretion - Beta-1

Liver: glycogenolysis - alpha-1 (beta-3)

Here's some adrenergic receptor info on kidney from "Clinical Anesthesia" including blood flow:

Alpha receptors in the kidney:

The kidney has an extensive and exclusive adrenergic innervation of the afferent and efferent glomerular arterioles, proximal and distal renal tubules, ascending loop of henle, and juxtaglomerular apparatus. The greatest density of innervation is in the thick ascending loop of Henle, followed by the distal convoluted tubules and proximal tube. Both alpha-1 and alpha-2 subtypes are found in the kidneys with the alpha-2 receptor dominating. The alpha-1 receptor is predominantly in the renal vasculature and elicits vasoconstriction which moderates renal blood flow. Tubular alpha-1 receptors enhance sodium and water reabsorption, leading to antinatriuresis, whereas tubular alpha-2 receptors promote sodium and water excretion.

Beta receptors in the kidney:

The kidney contains both beta-1 and beta-2 receptors, with the beta-1 being predominant. Renin release from the juxtaglomerular apparatus is enhanced by beta stimulation. The beta-1 receptor evokes renin release in humans. Renal beta-2 receptors also appear to regulate blood flow at the vascular level. They have been identified pharmacologically and mediate a vasodilatory response.

Dopaminergic receptors:

Kidney and mesentery:

The distribution of DA receptors in the renal vasculature is well known, but DA receptors have ofther functions within the kidney. DA1 receptors are located on renal tubules, which inhibit sodium reasbsorption with subsequent natriuresis and diuresis. The natriuresis may be the result of a combined renal vasodilatation, improved CO, and tubular action of the DA1 receptors. Juxtaglomerular cells also contain DA1 receptors, which increase renin release when activated. This action modulates the diuresis produced by DA1 activation of the tubules.

DA has unique autonomic effects by activating specific peripheral dopaminergic receptors, which promote natriuresis and reduce afterload via dilatation of the renal and mesenteric arterial beds. … Subtle changes in the DA-NE balance with aging may account for the diminished ability of the aged kidney to excerete a salt load.

... and some more vague stuff on hepatic blood flow that I didn't totally follow...

Re: autonomic nerves and kidney/liver under GA (Vet nursing Q.)

Lindsey Edwards — Mon, 15 Jun 2015 19:20:51 GMT

Blunting of sympathetic reflexes and reduced perfusion and ability to regulate blood pressure etc? Metabolism reduced and clearance times affected more in compromised patients?

Re: autonomic nerves and kidney/liver under GA (Vet nursing Q.)

Richard Carter — Mon, 15 Jun 2015 17:48:24 GMT

presumably blood pressure, heart rate and PCO2/O2 levels, the effect of pain/ anxiety with the effects of adrenaline / inflammatory agents and the processing of pre-ga, ga, and post ga medications by an anaesthetised patient?? sedatives and barbiturates being depressive, ketamine stimulating, lean patients vs fat ones affecting recycling and effective dosage rates, toxicity medications increased age, cardiac and pulmonary disease?

Start with 'overdose will cause death by suppression of the autonomic system'? No idea - quite afternoon and filling up the time.