Urethral retrograde urohydropropulsion on male dog
- To flush uroliths lodged in the urethra into the bladder, to restore urethral patency. Uroliths flushed into the bladder lumen can then be removed via cystotomy
- Urethral obstruction with uroliths should be confirmed with radiography prior to performing retrograde urohydropulsion (see Retrograde urethrography/vaginourethrography)
- Sedation or general anaesthesia is recommended for the painful or alert patient, but may not be required for the severely depressed.
- Any animal with urethral obstruction should undergo emergency assessment and stabilization, including intravenous catheterization, blood sampling for an emergency minimum database, and fl uid therapy for correction of acid–base and electrolyte abnormalities.
- Hyperkalaemia associated with bradycardia should be treated aggressively.
- As required for Urethral catheterization – (a) male dog; flexible nylon urinary catheters are referred to Foley catheters for urohydropulsion
- Hypodermic needles: 21 G, 1.5 inch
- 3-way taps
- Intravenous extension tubing
- 20–35 ml syringes
- Sterile intravenous fl uid administration set and empty fluid bag or commercial closed urine collection system
- Sterile isotonic fl uids (e.g. saline, lactated Ringer’s solution)
- Sterile water-soluble lubricant
Patient preparation and positioning
- As required for Urethral catheterization – (a) male dog.
- Lateral recumbency is recommended.
- The prepuce should be cleaned and fl ushed with antiseptic (excluding alcohol).
- Decompress the bladder if overdistended by cystocentesis, using a needle attached to intravenous extension tubing, a 3-way tap and a syringe. This apparatus permits decompression without repeated puncturing of the bladder wall. The needle is held in position within the bladder, while an assistant withdraws urine.
- Fill one 10 ml (or 12 ml) syringe with 5 ml saline and another with 5 ml of lubricant. Attach the syringes to a 3-way tap to permit mixing.
- Insert a lubricated large-bore male dog urinary catheter into the urethra (see Urethral catheterization).
- Instil 3–8 ml of the lubricant mixture around the uroliths. The tip of the catheter should remain distal to the uroliths. Never attempt to force uroliths retrograde with the tip of the catheter.
- Insert a gloved index fi nger into the rectum and occlude the urethral lumen by compressing the urethra against the fl oor of the bony pelvis
- With a moistened gauze swab, occlude the distal urethra by compressing the distal tip of the penis around the urinary catheter.
- Fill a large syringe with sterile isotonic solution. As a guide, the normal bladder will accommodate approximately 7–11 ml/kg bodyweight, but this volume is most often not required.
- Attach the syringe to the urinary catheter.
- Push sterile isotonic solution into the urethra, with the goal of dilating the urethral lumen around the uroliths.
- Once the urethra is dilated, immediately release digital compression of the pelvic urethra.
- Continue fl ushing fl uid through the urinary catheter and urethral lumen to propel uroliths into the urinary bladder. Repeated occlusion of the pelvic urethra and flushing of the urethra may be required. Use caution not to overdistend the bladder lumen with fluid. Palpate the bladder regularly to check for overdistension and repeat bladder decompression if required.
- Confirm successful retrograde urohydropulsion of uroliths into the bladder by retrograde urethrography.
- If the animal is not taken to surgery immediately for removal of uroliths from the bladder, placement of an indwelling urethral catheter is recommended pending surgery, to maintain urine flow.
- Urethral rupture (rare
- Urinary tract infection
Source : BSAVA Guide to Procedures in Small Animal Practice