Which investigations are essential to assess the severity of hypothermia in a primary care patient?

To assess the severity of hypothermia in a primary care patient, the essential investigations include:

• Measurement of core body temperature using a reliable method that provides either a direct measurement or a direct estimate of core temperature accurate to within 0.5ºC. Suitable sites include pulmonary artery catheter, distal oesophagus, urinary bladder, zero heat-flux (deep forehead), sublingual, axilla, or rectum. Peripheral sites such as axilla or sublingual may be less accurate if the core temperature is outside the normal range (36.5°C to 37.5°C) ¹.
• Clinical assessment of vital signs and symptoms to evaluate the patient's general condition and identify complications related to hypothermia, such as cardiovascular instability or altered consciousness ¹.
• Basic blood tests may be considered to assess metabolic disturbances, electrolyte imbalances, and organ function, although specific tests are not detailed in the provided guidelines.
• Electrocardiogram (ECG) may be useful if there is suspicion of cardiac complications, as hypothermia can cause arrhythmias ⁵.

In primary care, the priority is accurate temperature measurement and clinical assessment to determine severity and need for urgent referral or hospital management.