Prognostic value of haematological indices in sea turtles presenting for cold-stunning (sustained hypothermia)

In sea turtles presenting for cold-stunning (sustained hypothermia), what blood analytes routinely evaluated at intake provide the most prognostic value?

Prognosis.

Ten studies were included in this evaluation including the following study designs: eight retrospective case series, one cross-sectional, and one retrospective cohort.

Weak.

The most consistent finding across all included studies in cold-stunned sea turtles was acidosis (suspected both respiratory or metabolic components) characterised by reduced blood pH, elevated partial pressure of carbon dioxide (pCO₂), and reduced partial pressure of oxygen (pO₂). However, this finding was not necessarily linked with failure of rehabilitation. Rather, sea turtles presenting for cold-stunning that did not survive rehabilitative therapy were typically in extreme states of homeostatic derangement involving acidosis, but often in conjunction with additional abnormalities (e.g. anaemia, sepsis, organ failure or dysfunction, pneumonia, etc.).

As might be expected, the evaluated literature did not reveal a single or series of blood analytes that were definitively linked with the success or failure of rehabilitation in sea turtles presenting for cold-stunning. However, they did identify analytes that may provide the most clinical value in this clinical situation including packed cell volume (PCV), estimated white blood cell count (WBC), total and / or ionised calcium, pH, potassium (K), and lactate. Review of the available studies on the topic provides insightful information that can aid clinicians addressing this syndrome to triage and treat affected individuals most effectively. It also elucidated areas of opportunity for further research.