"sleeping bag or not thread lead me to post this: http://www.princeton.edu/~oa/safety/hypocold.shtml 4. Signs and Symptoms of Hypothermia a. Watch for the "-Umbles" - stumbles, mumbles, fumbles, and grumbles which show changes in motor coordination and levels of consciousness b. Mild Hypothermia - core temperature 98.6 - 96 degrees F Shivering - not under voluntary control Can't do complex motor functions (ice climbing or skiing) can still walk & talk Vasoconstriction to periphery c. Moderate Hypothermia - core temperature 95 - 93 degrees F Dazed consciousness Loss of fine motor coordination - particularly in hands - can't zip up parka, due to restricted peripheral blood flow Slurred speech Violent shivering Irrational behavior - Paradoxical Undressing - person starts to take off clothing, unaware s/he is cold "I don't care attitude" - flattened affect d. Severe Hypothermia - core temperature 92 - 86 degrees and below (immediately life threatening) Shivering occurs in waves, violent then pause, pauses get longer until shivering finally ceases - because the heat output from burning glycogen in the muscles is not sufficient to counteract the continually dropping core temperature, the body shuts down on shivering to conserve glucose Person falls to the ground, can't walk, curls up into a fetal position to conserve heat Muscle rigidity develops - because peripheral blood flow is reduced and due to lactic acid and CO2 buildup in the muscles Skin is pale Pupils dilate Pulse rate decreases at 90 degrees the body tries to move into hibernation, shutting down all peripheral blood flow and reducing breathing rate and heart rate. at 86 degrees the body is in a state of "metabolic icebox." The person looks dead but is still alive. e. Death from Hypothermia Breathing becomes erratic and very shallow Semi-conscious Cardiac arrythmias develop, any sudden shock may set off Ventricular Fibrillation Heart stops, death 5. How to Assess if someone is Hypothermic If shivering can be stopped voluntarily = mild hypothermia Ask the person a question that requires higher reasoning in the brain (count backwards from 100 by 9's). If the person is hypothermic, they won't be able to do it. [Note: there are also other conditions such as altitude sickness that can also cause the same condition.] If shivering cannot be stopped voluntarily = moderate - severe hypothermia If you can't get a radial pulse at the wrist it indicates a core temp below 90 - 86 degrees The person may be curled up in a fetal position. Try to open their arm up from the fetal position, if it curls back up, the person is alive. Dead muscles won't contract only live muscles.