Cystocentesis

Cystocentesis is a veterinary procedure, performed mainly on dogs and cats, in which a needle is inserted into the urinary bladder through the abdominal wall to obtain a urine sample. It can be done blind, stabilizing the bladder by external palpation, or under ultrasound guidance that lets the practitioner watch the bladder and guide the needle in real time. Its main use is diagnostic, providing an uncontaminated urine sample for urinalysis, biochemical testing or culture for bacterial identification and antibiotic sensitivity with less risk of contamination than a free catch or catheterized sample, though it can also be used as a last resort to relieve pressure from a urethral obstruction, carrying a risk of rupture in a severely distended bladder, and it is used in research into drug pharmacokinetics and biomarkers.