In sports, to have ice in your veins is to be cold-blooded and clutch. In medicine, to have ice in your veins is a very serious medical condition associated with hypothermia and frost emboli.
Etiology
There is very little information in the literature, especially The House of God, regarding the acquisition of ice in one's veins. It certaintly couldn't have been preexisting or, if it did, would have melted due to our naturally body temperature of about 98.6 degrees Fahrenheit. The expert concensus is that the ice was acquired later in life, with the most obvious source being intravenous injection, either as a form of street recreation like injection heroin or an accidental doctor's order ("Please flush with 10 cc of ice cubes.")
Diagnosis
Diagnosis is made on clinical grounds. 90% of patients with ice in their veins have the triad of hypothermia, frigid countenance, and palpable ice cubes in visible venous vessels.
Treatment
Time, maybe even a warm blanket.
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