206 Environmental Emergencies
HEAT, COLD AND DROWNING(iii) Severe hypothermia: the patient is comatose and may appear dead
with an undetectable pulse, absent reflexes, unrecordable blood
pressure and fixed pupils.
3 Record the core temperature rectally with a low-reading thermometer. This
is more accurate than any tympanic membrane device.
4 Send blood for FBC, U&Es, CK, coagulation profile and blood sugar level.
Check serum lipase/amylase, as pancreatitis may be associated. Send ABGs.
5 Perform an ECG.
(i) Look for evidence of bradycardia, low-voltage complexes, atrial
fibrillation and prolongation of the QT interval.
(ii) Osborn ‘J’ waves (a slurred notching of the terminal portion of
the QRS complex) may be present at core temperatures of
<32°C
(a) Osborn waves are not pathognomic and are seen in other
conditions such as subarachnoid haemorrhage, head trauma
and hypercalcaemia.
6 Request a CXR.MANAGEMENT
1 Mild hypothermia
(i) Remove wet clothing and cover the patient in warm blankets
and layers of polythene to minimize evaporative, convective and
conductive heat loss.
(ii) Rehydrate the alert but shivering patient, and give high-energy
food and drinks.
2 Moderate and severe hypothermia (core temperature ≤32°C )
(i) Remove wet clothing and cover the patient in warm blankets
and layers of polythene to minimize evaporative, convective and
conductive heat loss.
(ii) Give high-flow, warmed 42–46°C (108–115°F), humidified
oxygen.
(iii) Give i.v. fluids cautiously through a warming device at 43°C
(109°F). Pulmonary oedema may be precipitated by excessive
fluid administration.
(iv) Use a forced-air re-warming blanket, e.g. Bair Hugger
®, and
aim for a core temperature rise of 1°C/h in younger patients and
0.5°C per h in the elderly.
(v) Take extreme care with any airway manoeuvres such as
endotracheal intubation, as this may precipitate ventricular
fibrillation (VF) in severe hypothermia. Call the senior ED doctor
for help.