1. How to deal with low core body temperature? Joshua BennettM1073

2.  Relevance to Wilderness Medicine  Medical emergency  >50% mortality in patients aged 70 or older with temperature <32 ° C (Longmore et al., 2010)  Personal experience

3.  1 hour from car park, notice young man slumped against stone wall.  Mumbling inaudibly and shivering violently.  Half empty bottle of vodka.  Equipment is your backpack containing what you would normally take for a day outdoors. January 2011, Lake District, Sca Fell

4.  Grades and types of hypothermia  Need to know basics in order to treat.  Essentials of hypothermia management  Do’s and Don'ts  Strategies to treat hypothermia  Spontaneous rewarming  Active external rewarming  Active core rewarming  Resuscitation and hypothermia

5. Severity  Grade I – conscious and shivering  Grade II – impaired consciousness / no shivering  Grade III – unconscious or cardiac instability  Grade IV – apparent death KEY POINT: Cold patients who have stopped shivering will cool at an accelerating rate (due to minimal heat generation).

6. Severity  Grading system Speed of onset  Acute / immersion  Subacute / exhaustion / injury  Subchronic / urban

7. irway reathing irculation isability nvironment / evacuation

8. KEY POINT: ‘Core afterdrop’ or ‘rewarming collapse’ can occur if rewarming is too quick.

9. Do:  Remove from cold  Replace wet clothing  Insulate  Handle gently  Monitor regularly Don’t:  Suppress shivering  Give alcohol  Put in warm shower/bath  Warm peripheries KEY POINT: Sudden movements may trigger ventricular fibrillation. (NESRA Medical Sub-Committee, 2010)

10.  May reverse Grade I hypothermia  Requires patient to generate heat  Layer system  Insulate from ground  Cover head and neck (leave airway!) ‘Hypothermia wrap’

11.  Indications:  Grade II hypothermia or worse  Trauma or other co-morbidity  Apply heat source to armpits, groin and flanks  Should be warm not hot- risk of burning patient

12.  Airway warming  Air humidifier devices  Warm tubing in warm drink  Warmed IV fluids  Microwave  Can warm giving set in warm drink  Thoracic lavage  Peritoneal dialysis  Cardiopulmonary bypass invasive (Danzl and Lloyd, 2001)

13.  Check carefully for pulse for 1 minute  “No-one is dead until they are warm and dead”  >33 ° C “Active core rewarming techniques are the primary therapeutic modality in hypothermia victims in cardiac arrest or unconscious with a slow heart rate.” (Emergency Cardiac Care Committee, 1992)

14.  1 hour from car park, notice young man slumped against stone wall.  Mumbling inaudibly and shivering violently.  Half empty bottle of vodka.  Equipment is your backpack containing what you would normally take for a day outdoors. January 2011, Lake District, Sca Fell

15. KEY POINT: Cold patients who have stopped shivering will cool at an accelerating rate (due to minimal heat generation). KEY POINT: ‘Core afterdrop’ or ‘rewarming collapse’ can occur if rewarming is too quick. KEY POINT: Sudden movements may trigger ventricular fibrillation.

16. References  Danzl, D. F. and Lloyd, E. L. (2001) Medical Aspects of Harsh Environments. Borden Institute.  Emergency Cardiac Care Committee. (1992) 'Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiac Care', Journal of the American Medical Association.  Longmore, M., Wilkinson, I. B., Davidson, E. H., Foulkes, A. and Mafi, A. R. (2010) Oxford Handbook of Clinical Medicine.8th ed:  NESRA Medical Sub-Committee. (2010) Mountain Rescue for Casualty Care student notes.2nd ed: