Blood Tests

Blood should be taken for arterial blood gas, full blood count, electrolytes/urea/creatinine, calcium, magnesium, coagulation studies and amylase [2].

A variety of abnormalities are possible:

• Hypoglycaemia and obvious electrolyte disturbance should be treated [2].
• Hypokalaemia is very commonly observed due to intracellular potassium shifts. Treat if severe but use caution as the potassium will increase with re-warming.
• Hyperkalaemia my represent cell necrosis. Very high levels (>10 mmol/L) are predictive of death and contraindicate re-warming.
• Elevated creatinine is also seen and may not be a true reflection of renal function.
• A coagulopathy similar to disseminated intravascular coagulopathy is common.
• Loss of intravascular fluid causes haemocrit to rise around 2% for each.1 C fall in core temperature. Lower than expected haemocrit may suggest blood loss.
• Thrombocytopenia may occur due to marrow suppression or hepato-splenic sequestration [2].