Injectable Anaesthetics For Cats

Below are guidelines for vets who don't have gas anaesthetic machines
e.g. animal shelter work in the field and cost considerations. Zoletil, Domitor and isoflurane are costly.

CATS
1. XYLAZINE + ZOLETIL ANAESTHESIA

5 kg
Xylazine 0.1 ml + Zoletil 100 0.1 ml in one syringe IM
If insufficient, top up with Zoletil 0.01 ml IV to effect.

In one case of a 5kg male
cat, I topped up with Zoletil 100 at 0.05 ml + 0.1 ml saline IV after 10 minutes of the xylazine 0.1 ml + Zoletil 0.1 ml IM combination. Effective analgesia for neuter.


2. XYLAZINE + KETAMINE
3-4 kg
Xylazine 0.1 ml + Ketamine 0.4 ml in one syringe IM. If insufficient, top up with Zoletil 0.01 ml IV to effect.
For cats 4-6 kg, double the above dosage IM.
I use this formula frequently for spay and neuter of cats without problems.
Duration of anaesthesia is half an hour.

3. DOMITOR + XYLAZINE
Domitor 0.1 ml + Xylazine 0.1 ml in one syringe IM.
If insufficient, top up with Zoletil 0.01 ml IV to effect. Domitor is expensive for stray cat spays.
I have not used this before.

4. IF USED ALONE, adverse effects are as follows:
1. Insufficient analgesia. Needs to top up IV.
2. Salivation and legs rigid (ketamine IM)
3. Wakes up fast
Combined with xylazine will make the cat sleep longer.