Historical and physical parameters as predictors of severe hyperkalemia in male cats with urethral obstruction

Authors

  • Justine A. Lee DVM, DACVECC,

    1. Department of Clinical Studies, School of Veterinary Medicine, Matthew J. Ryan Veterinary Hospital, University of Pennsylvania, Philadelphia, PA
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  • Kenneth J. Drobatz DVM, MSCE, DACVECC, DACVIM

    1. Department of Clinical Studies, School of Veterinary Medicine, Matthew J. Ryan Veterinary Hospital, University of Pennsylvania, Philadelphia, PA
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  • Cases presented to: Matthew J. Ryan, Veterinary Hospital at the University of Pennsylvania, Philadelphia, PA, 19104.

  • Presented as an abstract at the 7th Annual Meeting of the Veterinary Emergency and Critical Care Symposium, Orlando, FL, September 2000.

  • Dr. Lee's current address is Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, MN.

Address correspondence and reprint requests to:
Dr. Justine A. Lee, Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Minnesota, 1365 Gortner Avenue, St. Paul, MN 55108.
E-mail: leexx586@umn.edu

Abstract

Objective: To evaluate selected historical and physical parameters as predictors of hyperkalemia in male cats with urethral obstruction.

Design: Retrospective study.

Setting: Veterinary teaching hospital.

Animals: Two hundred and twenty-three male cats.

Interventions: None.

Measurements and main results: The metabolic derangements of 223 male cats that presented with urethral obstruction from 1997 through 1999 were reported in a companion article. Approximately 12% of the cats had multiple, life-threatening metabolic derangements. In the present study, historical and physical parameters were evaluated as predictors of hyperkalemia (K+≥8.0 mmol/L) in cats with urethral obstruction. The 4 historical parameters significantly associated with hyperkalemia were: first time obstruction, outdoor status, anorexia, or vomiting. The 5 physical parameters significantly associated with hyperkalemia were: rectal temperature, heart rate, respiratory rate, pulse quality, and the presence of arrhythmia. Of the physical parameters, a rectal temperature below 95–96.6°F (35–35.9°C) or a heart rate below 120 b.p.m. were the most accurate predictors. When used in combination (i.e., evidence of bradycardia and hypothermia), the specificity for hyperkalemia was 98–100%.

Conclusions: Rectal temperature and heart rate were the best parameters for predicting hyperkalemia in this population.

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