LAUSR

ABSTRACT Background Hypophosphatemia is commonly observed in unselected human intensive care unit (ICU) patients, and it has been associated, although inconsistently, with worse outcomes and longer duration of hospitalization (DOH). The incidence of hypophosphatemia and its association with mortality and DOH in ICU canine patients is unknown. Objectives The aims of this study were to determine the occurrence of hypophosphatemia in unselected ICU canine patients and its association with mortality and DOH. Methods The medical records of all dogs admitted to the Teaching Hospital ICU between January 2019 and December 2023 were retrospectively reviewed. Dogs with hypophosphatemia (serum phosphate < 0.9 mmol/L) were identified. For every hypophosphataemic dog included in this study, two age‐matched control, non‐hypophosphataemic dogs, closely admitted to the ICU in time, were included. Results In total, 3233 medical records were reviewed. Hypophosphatemia was noted in ≥ 1 day of hospitalization in 32 dogs (0.99%). The age‐matched case and control groups had a median (range) age of 8.0 (1.0–14.0) years. The survival to discharge rates of both hypophosphataemic and control groups were 78% (25/32 and 50/64, respectively), and their DOH (median, 3.5 days; range 1.0–9.0 and median 3.0 days; range 1.0–25.0, respectively) were not significantly different (p = 0.557). Serum phosphate concentration was not correlated with the DOH (p = 0.649). Conclusions Hypophosphatemia was noted in only 1% in this canine ICU patient population and was not associated with the survival to discharge and DOH.