Short- and long-term outcome and factors predicting survival after surgical tube cystostomy for treatment of obstructive urolithiasis in small ruminants

Abstract

Objective: To evaluate outcome of small ruminants after tube cystostomy without urethral flushing.

Study design: Retrospective clinical study.

Animals: Small ruminants (n=63; 50 goats, 13 sheep).

Methods: Medical records (January 1996-October 2003) for all small ruminants undergoing tube cystostomy were analyzed. Signalment, laboratory data, intraoperative findings, urolith type, and postoperative outcome were compared. Long-term follow-up was obtained at 6 and > or= 12 months postoperatively.

Results: Most animals were castrated males. Pygmy goats were overrepresented. Mean time to normal urination after tube cystostomy was 11 days, and mean hospitalization was 14 days. Seventy-six percent of animals were successfully treated with tube cystostomy (90% of those discharged from hospital). Short- and long-term survival was good for those animals with follow-up data. Reobstruction occurred in <20% of animals at 6 and 12 months. Goats, castrated males, and animals with normal serum potassium, no fluid in the abdomen, or no urethral process amputation were more likely to survive. Stone type, bladder appearance, and age at castration were not associated with outcome.

Conclusion: Surgical tube cystostomy without urethral flushing is an effective technique for resolution of obstructive urolithiasis in small ruminants.

Clinical relevance: Goats, small ruminants with an intact urethral process, absence of abdominal fluid, and serum potassium concentration <5.2 mEq/L at admission were all associated with survival after tube cystostomy. Castrated males may also be more likely to survive. These factors should be considered in management of small ruminants with urolithiasis.