# Retrospective Evaluation of the Prognosis and Prevalence of Hyperchloremia in Dogs and Cats

## TL;DR

This study found that high chloride levels in dogs and cats are common and linked to higher death rates, especially when the condition develops in the hospital.

## Contribution

The study provides new insights into the prevalence and mortality risk of hyperchloremia in veterinary patients.

## Key findings

- Hyperchloremia was found in 21.1% of dogs and 9.1% of cats.
- Hospital-acquired hyperchloremia in dogs had a higher case-fatality rate than prehospital cases.
- Various diseases like neurological and urological disorders were associated with hyperchloremia.

## Abstract

To determine the prevalence, case‐fatality rate, and primary disease processes associated with high corrected chloride concentration (hyper[Cl−]) in dogs and cats.

Single‐center retrospective study.

Electrical medical records were reviewed to identify dogs and cats with at least one chloride and sodium concentration measured simultaneously during a 60‐month period.

A total of 17,120 dogs and 4197 cats presented to a veterinary teaching hospital.

None.

Measured hyper[Cl−] was diagnosed in 18.1% (3092/17,120) dogs and 9.4% (396/4197) cats. Corrected hyper[Cl−] was diagnosed in 21.1% (3607/17,120) dogs and 9.1% (384/4197) cats. The case‐fatality rates were higher in animals with corrected hyper[Cl−] than in those with normal corrected [Cl−] (p < 0.0001). The case‐fatality rate was higher in dogs with measured hyper[Cl−] than in those with corrected hyper[Cl−] (p = 0.011). Of the dogs and cats with corrected hyper[Cl−], a total of 50.9% (1835/3607) dogs and 38.3% (147/384) cats were categorized as prehospital corrected hyper[Cl−], whereas a total of 39.5% (1424/3607) dogs and 48.7% (187/384) cats with corrected hyper[Cl−] were categorized as hospital‐acquired corrected hyper[Cl−]. The case‐fatality rate of dogs and cats with hospital‐acquired corrected hyper[Cl−] was higher than that of prehospital corrected hyper[Cl−] in dogs (p < 0.0001) but not in cats (p = 0.9). Various primary disease processes, including neurologic and urologic diseases, were identified in animals with corrected hyper[Cl−].

Corrected hyper[Cl−] was a common electrolyte abnormality identified in dogs and cats, and it was associated with higher case‐fatality rates than normal corrected [Cl−]. Hospital‐acquired corrected hyper[Cl−] was less common but was associated with a higher case‐fatality rate than prehospital corrected hyper[Cl−] in dogs. Further investigation of corrected hyper[Cl−] in association with its morbidity and mortality and the role of therapy to target normal [Cl−] is warranted.