Surgery and Radiology Section

Collection of urine in dogs

URINARY CATHETERIZATION

Indication

• Obstruction of urethra
• Urinalysis
• When no bladder is palpable
• For maintaining  urethral patency
• To measure urine output.

Types of catheter

• Metal catheter (rigid) - female
• Polyethylene catheter (semi rigid plastic) - male
• Soft rubber catheter
• Foley's catheter.

Techniques

In male dogs

• It should be inserted aseptically.
• Male dogs are generally easy to catheterize and seldom require sedation (or) anaesthesia.
• The dog is restrained in lateral recumbency.
• The penis is extruded  out by retracting the prepuce caudally towards the scrotum. The penis is held in position.
• A non irritating surgical scrub, such as povidone iodine (or) chlorhexidine, is used to clean the urethral opening and the tip of the penis to remove surface bacteria and debris.
• The distance from the urethral opening to the bladder should be estimated by measuring the distance from the end of the pelvis.
• The size of the dog determines the size of the catheter (3.5 to 10 mm).
• The sterile catheter should be lubricated with sterile water soluble lubricant, inserted into the urethral opening, and advanced along the urethra.
• Some resistance is usually felt at the level of the ischial arch and prostate gland, but gentle firm pressure advances the catheter past this point.
• The catheter should not be forcibly advanced if urethral obstruction is suspected, as this could cause urethral damage (or) rupture.
• Once the catheter has been passed into the bladder lumen, urine usually flows freely out the end of the catheter.
• The catheter should never be pushed too far into the lumen, as it may damage the bladder wall (or) form a kink.
• A syringe is immediately attached to the catheter for urine collection.
• After completing the urine collection ,the catheter is withdrawn from the bladder slowly.

In female dogs

• The animal should be placed in lateral or sternal recumbency by positioning their rear limbs off the end of the table.
• Excessive hair should be removed from the genital area.
• Placement of urinary catheter may be accomplished either by palpation or visualization of the urethral papilla. It is palpated with a lubricated, gloved finger.
• The catheter is placed caudal to the papilla and should slide easily into the bladder.
• Smaller dogs, obese dogs, and bitches in heat are harder to palpate, vaginal speculum (or) vaginoscopy may be useful for this purpose.