Corticosterone, Lactate, and Injury Severity as Short-Term and Long-Term Prognostic Indicators in Eastern Box Turtles (Terrapene carolina carolina) with Traumatic Injuries Admitted to a Wildlife Rehabilitation Clinic
The hypothalamic–pituitary–adrenal axis is often disregulated during critical illness or following traumatic injury, and both elevated and reduced glucocorticoid levels have been associated with poor prognoses in multiple species. In eastern box turtles (Terrapene carolina carolina), hyperlactatemia has been identified as a negative prognostic indicator, prompting the question of whether glucocorticoids become elevated in this species during hospitalization. This study examines the role of corticosterone in relation to lactate, other blood-based parameters, and triage scores during hospitalization of eastern box turtles with traumatic injuries on survival at 24 h, 1 wk, and 1 month. Eastern box turtles with higher triage scores had lower survival at 24 h and at 1 month, and lactate concentration at admission was associated negatively with survival at 24 h. Turtles in which plasma corticosterone levels increased in the first 24 h were more likely to die in the first week than turtles in which corticosterone decreased or remained the same, but this was not statistically significant. The results of this study demonstrate the potential role of the hypothalamic–pituitary–adrenal axis in survival of eastern box turtles with traumatic injuries.Abstract
Corticosterone responsiveness in hospitalized eastern box turtles (Terrapene carolina carolina). Blood from eight eastern box turtles was sampled at 0, 30, 120, and 360 min and corticosterone was measured from the isolated plasma using enzyme-linked immunoassays. Each line represents an individual turtle, and each point represents a sampling time. Corticosterone values did not differ significantly between time points in any turtle.
Lactate concentrations in surviving and nonsurviving eastern box turtles (Terrapene carolina carolina) at 24 h. Lactate was measured in the whole blood of eastern box turtles with traumatic injuries on the day of admission to the hospital. Turtles who survived to 24 h (white) had significantly lower blood lactate levels than turtles who died within the first 24 h of hospitalization (gray, * indicates statistical significance, P < 0.05).
Corticosterone change in the first 24 h of hospitalization in eastern box turtles (Terrapene carolina carolina). Corticosterone was measured in plasma of eastern box turtles on the day of admission and at 24 h after admission. The difference in concentration between 0 h and 24 h is shown, with turtles who survived the first week of hospitalization on the left (white) and those who did not survive on the right (gray). These data do not include turtles who died in the first 24 h. Though not statistically significant, turtles who died were more likely to have corticosterone levels that increased over the first 24 h (P = 0.09).
Lactate concentrations associated with triage scores in eastern box turtles (Terrapene carolina carolina). Turtles were assigned trauma triage scores using the criteria outlined in Table 1. Lactate concentrations measured in whole blood on the day of admission were compared between triage scores, and turtles with a triage score of 8 had higher blood lactate concentrations than turtles with scores less than 8 (* indicates statistical significance, P < 0.05).
