This was a retrospective study of 223 male cats that presented consecutively to a university teaching hospital with urethral obstruction and fit the selection criteria. Most of these cats were relatively stable without serious metabolic derangements. The median duration of clinical signs was 3 days. Most had signs typical of urethral obstruction, including stranguria and dysuria. Other signs included vocalizing, lethargy, anorexia, vomiting, excess licking of the perineal area, and diarrhea. One cat was reported to have seizures. Sixty-eight cats were hypothermic, and 19 were hyperthermic. Twenty-two of the cats had mild bradycardia, 12 had moderate bradycardia, and 10 had severe bradycardia (heart rate 100 bpm or less). The pH was measured in 198 of the cats, and only 6% has severe acidemia (pH < 7.1). Only 12% of the cats were hyperkalemic. Most cats with urethral obstruction in this study had mild electrolyte and blood gas changes. Most survived and were discharged from the hospital.

COMMENTARY: Feline urethral obstruction is a common presenting complaint in veterinary medicine. Changes in electrolyte variables usually occur together, and hyperkalemia is often associated with ionized hypocalcemia and acidemia. However, cats that are relatively stable respond well to treatment.

Characterizations of the clinical characteristics, electrolytes, acid-base, and renal parameters in male cats with urethral obstruction. Lee JA, Drobatz KJ. J VET EMERG CRIT CARE 13:227-233, 2003.