Urinary Obstruction

Urinary obstruction can occur in cats, dogs and other species such as ferrets. It can occur in both males and females, although most commonly males are affected. It is commonly caused by bladder stones that get stuck in the urethra and prevent passage of urine, but it can also be caused by muscle spasms in the urethra, cystitis, mucous plugs and certain cancers.

It can be a life threatening veterinary emergency, particularly in male cats where the inability to urinate leads to a rapid build-up of toxic substances and if left untreated, can lead to abnormal heart rhythms and death.

What to look for?

The signs in dogs and cats are quite similar – they will often be seen straining to urinate but producing no urine or producing only a few drops. Many animals will appear to be in pain as they attempt to urinate or may vocalize. In cats, it may also cause extreme lethargy, vomiting or even collapse.

No urine in the litter box or just drops of discolored urine may be an indicator that your cat has a urinary obstruction.

What to do if you suspect urinary obstruction?

This is a true veterinary emergency, particularly in male cats. Left untreated, this condition will be fatal, but with appropriate and rapid treatment the vast majority of pets can be saved. It is often difficult for owners to tell the difference between urinary obstruction and less serious conditions such as a bladder infection. This is something that your emergency veterinarian can figure out from their examination. The take-home message is if you suspect a urinary obstruction, get your pet to the vet!

How do we treat urinary obstruction?

Initially, it is treated by stabilizing the pet – often using intravenous fluids and pain medications. Once the pet is stabilized, then they are sedated and a urinary catheter is placed in the urethra to unblock it. Once this is achieved, your pet will be treated with fluids and any other medications that are required depending on your pet’s individual condition. The next step will be to ascertain why they became blocked in the first place – do they have cystitis, which will need medical management? Do they have stones that will require surgery? Your emergency veterinarian will be able to talk to you about the individual workup plan for your pet.

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