Evaluation of platelet function using multiple electrode platelet aggregometry in dogs with septic peritonitis

ObjectiveTo assess platelet function via multiple electrode platelet aggregometry (MEPA) in dogs with septic peritonitis and in healthy dogs. The secondary aim was to determine if there is prognostic significance to changes in platelet function observed in septic dogs. DesignProspective, observational cohort study conducted from January 2012 to March 2014. SettingUniversity teaching hospital. AnimalsTwenty dogs with septic peritonitis and 23 healthy dogs. InterventionsNone. Measurements and Main ResultsMEPA using arachidonic acid, adenosine diphosphate, and collagen (COL) as agonists was measured within 24 hours of diagnosis of sepsis. Compared to healthy dogs, platelet aggregation was reduced in dogs with septic peritonitis for all agonists (P < 0.01). Overall mortality rate was 40%. MEPA in response to COL was significantly reduced in nonsurvivors compared to survivors (P = 0.019). Using receiver-operating characteristic curve statistics, a COL-activated MEPA less than 43.5 aggregation units had a sensitivity and specificity of 85.7% and 90.9%, respectively, for predicting nonsurvival in dogs with septic peritonitis. ConclusionsCirculating platelets from dogs with septic peritonitis have diminished aggregation in response to multiple platelet agonists. MEPA may serve as an assessment tool for illness severity in this patient population.