Ca levels post thyriodectomy

RE: Ca levels post thyriodectomy

Chris Geddes — Wed, 17 Oct 2018 11:27:26 GMT

[quote user="Martin Atkinson"]

she cannot pill the cat, it won't eat low iodine diet and the methimazole transdermal gel didn't seem to work, she opted for I131 treatment.

[/quote]

Presume this was before liquid thiamazole became available. Shame :(

RE: Ca levels post thyriodectomy

dachsie_4 — Wed, 17 Oct 2018 01:41:21 GMT

The second cat sounds like some of my patients. You sort one thing and the next goes wrong.

Monika

RE: Ca levels post thyriodectomy

Martin Atkinson — Tue, 16 Oct 2018 11:15:37 GMT

Not going to be much help I'm afraid but having had two cats which remained permanently hypocalcaemic I have to say that this one reason why I'm reluctant to perform bilateral thyroidectomies these days. I consider myself a good soft tissue surgeon but heck if I can identify the parathyroids reliably every time and even less sure if I've preserved them. Having to treat the hypocalcaemia and possible hypothyroidism indefinitely is a lot more hassle than continual medication with Felimazole!

However, we have one owner who had a cat that suffered permanent hypocalcaemia after bilateral thyroidectomy so when the next one became bilaterally hyperthyroid, as she cannot pill the cat, it won't eat low iodine diet and the methimazole transdermal gel didn't seem to work, she opted for I131 treatment. That one has become hypothyroid, also has CKD which makes balancing the TT4 level tricky. It also has autoimmune skin disease which is difficult to treat as she can't give tablets so I gave it a couple of injections of depomed and it became diabetic - fortunately she can give the insulin injections. Oh and its hypertensive but for some reason the cat will tolerate Amodip tablets crushed in its food. At least its not hypocalcaemic!!.

RE: Ca levels post thyriodectomy

Robin Grimmer — Tue, 16 Oct 2018 10:43:50 GMT

You need to switch from iv calcium to oral as the vitamin D needs calcium from the gi tract to work. These can take a while .

RE: Ca levels post thyriodectomy

dachsie_4 — Tue, 16 Oct 2018 09:24:11 GMT

Cat was 2.7kg before thyroid surgery, and now is 3.7kg, and we are using alfacalcidol at a dose of 0.03micrograms/kg initially and on the weekend increased it to 0.06.

our reference range is: normal 1.2mmol/l -1.6mmol/l

Not sure if he has shown clinical signs since initially come into hospital, was twitchy two days post op, so will reduce the iv calcium and see if he gets clinical.

thank you for the help.

RE: Ca levels post thyriodectomy

dachsie_4 — Tue, 16 Oct 2018 09:04:19 GMT

using alfacalcidol, hope compliance it good as this cat is hospitalised.

RE: Ca levels post thyriodectomy

Beats — Mon, 15 Oct 2018 19:14:30 GMT

I don't know what reference intervals are for those calcium results, but can take a while for damaged parathyroid to kick in again.

As said, Vitamin D can take a while to kick in... and depends on formulation...

It is the vitamin D dosing that is critical, not the calcium (which you can give as needed until not symptomatic and vit D has kicked in).

I would say likely to come right, but need to ride the initial rollercoaster a bit longer to achieve this.

what formulation of vitD are you using and what amounts in a cat weighing what weight?

You are aiming for the cat not to be symptomatic for low Calcium, rather than aiming for the calcium levels to be normal necessarily.

RE: Ca levels post thyriodectomy

Robin Grimmer — Mon, 15 Oct 2018 18:30:11 GMT

Which Vitamin D are you using? They vary widely in speed of onset. Calcitriol and alfacalcidol have the most rapid onset. Also check compliance. Are the owners able to medicate this cat? If not, maybe hospitalise it.