Retrospective evaluation of the influence of azotemia on plasma lactate concentrations in hypotensive dogs and cats (2008-2018): 337 cases.

OBJECTIVE: To evaluate the relationship between azotemia and plasma lactate concentration in hypotensive dogs and cats presented to an emergency department.
DESIGN: Retrospective case-control study.
SETTING: University veterinary teaching hospital. ANIMALS: The electronic medical record database was searched for dogs and cats presented to the emergency department that had severe azotemia (creatinine ≥ 443.1 μmol/L [5 mg/dL]), hypotension (systolic blood pressure ≤ 90 mm Hg), and a plasma lactate measurement within 2 h of each another. Non-azotemic, normotensive dogs and cats; non-azotemic, hypotensive dogs and cats; and azotemic, normotensive dogs and cats that presented to the emergency department were used as control populations.
INTERVENTIONS: None.
MEASUREMENTS AND MAIN RESULTS: Severely azotemic, hypotensive dogs (n = 10) and cats (n = 63) had a lower plasma lactate than non-azotemic, hypotensive dogs and cats (P = 0.031 and P < 0.001, respectively). Median plasma lactate concentrations in hypotensive dogs (1.75 mmol/L) and cats (1.90 mmol/L) with severe azotemia were within reference intervals.
CONCLUSIONS: Hypotensive dogs and cats with severe azotemia have decreased plasma lactate concentrations as compared to hypotensive, non-azotemic dogs and cats. The median plasma lactate in azotemic, hypotensive dogs and cats was within reference intervals. This may be due to either decreased cellular production of lactate or increased excretion of lactate. Further research is needed to determine which of these mechanisms is responsible and the clinical significance of plasma lactate concentrations in azotemic, hypotensive dogs and cats. © Veterinary Emergency and Critical Care Society 2020.