The association of blood lactate concentration with outcome in dogs with idiopathic immune-mediated hemolytic anemia: 173 cases (2003-2006).
OBJECTIVE
To determine the association of blood lactate with outcome and response to transfusion therapy in dogs with idiopathic immune-mediated hemolytic anemia (IMHA).


METHODS
Retrospective study.


METHODS
Urban veterinary small animal emergency hospital.


METHODS
One hundred and seventy-three client-owned dogs with IMHA.


METHODS
None.


RESULTS
Serial blood lactate concentration, therapeutic interventions, and outcome were recorded. Nonsurvivors were defined as those that died or were euthanized. One hundred and thirty-three dogs (77%) survived, 35 (20%) were euthanized, and 5 (3%) died. One hundred forty-five dogs (84%; 145/173) had a lactate concentration above the laboratory reference interval [0.46-2.31 mmol/L] on presentation. Blood lactate at presentation was higher in the nonsurvivors (median 4.8 mmol/L; 0.5-13.6) compared with survivors (median 2.9 mmol/L; 0.3-13.2) (P<0.01). All dogs presenting with hyperlactatemia that normalized (<2.0 mmol/L) within 6 hours of admission survived, whereas, 71% of dogs that had a persistent hyperlactatemia at 6 hours survived (P=0.034). Lactate was positively correlated with age, BUN, and alkaline phosphatase, and inversely correlated with PCV. Receiver operating curve analysis for lactate concentration at admission as a test for outcome had an area under the curve of 0.69 with an optimal lactate cutoff concentration of 4.4 mmol/L correctly predicting outcome 73% of the time (sensitivity 60%, specificity 77%).


CONCLUSIONS
Lactate concentration at presentation was significantly higher in nonsurvivors than survivors. Lactate was significantly correlated with previously reported outcome variables but lactate concentration at admission, as a predictor for outcome was less than optimal. However, serial lactate concentration measurements may be more predictive as patients with persistent hyperlactatemia 6 hours after admission were less likely to survive. Prospective studies evaluating serial lactate concentration while controlling for other variables may provide further insight into lactate measurement as a prognostic indicator in animals with IMHA.
Holahan
Melissa L
ML
Section of Critical Care, Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA. dettlof6@cvm.msu.edu
Brown
Andrew J
AJ
Drobatz
Kenneth J
KJ
D000744:Anemia, Hemolytic, Autoimmune / Q000097:blood / Q000453:epidemiology / Q000628:therapy / Q000662:veterinary*; D000818:Animals; D001784:Blood Gas Analysis / Q000662:veterinary; D001803:Blood Transfusion / Q000662:veterinary; D004283:Dog Diseases / Q000097:blood* / Q000453:epidemiology / Q000628:therapy; D004285:Dogs; D005260:Female; D019344:Lactic Acid / Q000097:blood*; D008297:Male; D010414:Pennsylvania / Q000453:epidemiology; D011379:Prognosis; D012189:Retrospective Studies; D016019:Survival Analysis; D016896:Treatment Outcome
D019344:Lactic Acid