Measurement of urinary 11-dehydro-thromboxane B₂ excretion in dogs with gastric dilatation-volvulus

Objective - To measure 11-dehydro-thromboxane B₂ (11-dTXB₂) in urine of healthy control dogs, dogs undergoing ovariohysterectomy, and dogs with gastric dilatation-volvulus (GDV) and assess the relationship between urinary 11-dTXB₂ concentrations in dogs with GDV and postoperative outcomes. Sample population - Urine samples from 15 nonsurgical control dogs, 12 surgical control dogs, and 32 dogs with GVD. Procedure - Urine samples were obtained from healthy pet dogs (ie, nonsurgical control dogs), dogs undergoing ovariohysterectomy at anesthetic induction and 1 hour following surgery (ie, surgical control dogs), and dogs with GDV at hospital admission and 1 hour following surgical derotation of the stomach (ie, GDV dogs). Urinary 11-dTXB₂ concentrations were determined with an ELISA and normalized to urinary creatinine (Cr) concentrations by calculation of the 11-dTXB₂-to-Cr ratio. Differences in median 11-dTXB₂-to-Cr ratios among dogs and before and after surgery were analyzed. Results - Urinary 11-dTXB₂-to-Cr ratios did not differ between nonsurgical control dogs and surgical control dogs before or after surgery. Urinary 11-dTXB₂-to-Cr ratios were significantly higher in GDV dogs at the time of hospital admission and 1 hour after surgery, compared with those of nonsurgical control dogs. Postoperative urine samples from GDV dogs had significantly higher 11-dTXB₂-to-Cr ratios than postoperative urine samples from surgical control dogs. Median urinary 11-dTXB₂-to-Cr ratios increased significantly in GDV dogs that developed postoperative complications. Conclusions and clinical relevance - Urinary 11-dTXB₂ concentration is increased in GDV dogs at the time of hospital admission and after surgical derotation of the stomach, compared with that of healthy dogs. An increased urinary 11-dTXB₂-to-Cr ratio following surgery is associated with an increased incidence of postoperative complications in dogs with GDV.