Aviat Space Envir Md
-
Aviat Space Envir Md · Apr 2002
Case ReportsDelayed treatment of frostbite injury with hyperbaric oxygen therapy: a case report.
The effects of hyperbaric oxygen therapy on skin microcirculation were evaluated by laser-Doppler flowmetry and vital capillary microscopy in a frostbite victim 2 wk after the injury. Laser-Doppler skin blood flow, measured in intact skin on the dorsum of the foot, decreased from 52 to 31 perfusion units during hyperbaric oxygen therapy. The number of visible nutritive capillaries in frostbitten areas on the toes increased from 2 to 12 per mm2, as measured immediately after the hyperbaric oxygen therapy. We conclude that hyperbaric oxygen therapy is capable of improving nutritive skin blood flow in frostbitten areas more than 2 wk after the injury.
-
Aviat Space Envir Md · Apr 2002
Voluntary hyperventilation into a simple mixing chamber relieves high altitude hypoxia.
Involuntary hyperventilation is a critical factor in acclimatization to a high altitude. Unacclimatized subjects do poorly when acutely exposed to high altitude. This may not be due to hypocapnia itself, but rather an associated symptom which inhibits hypoxic respiratory stimulation. ⋯ However, subjects voluntarily hyperventilating may overventilate and become disabled from severe hypocapnia. A simple mixing chamber is described which makes voluntary hyperventilation easier, safer, and possibly more effective. A subject breathing into a mixing chamber was able to maintain an SaO2 of 90% at 20,000 ft.
-
Aviat Space Envir Md · Apr 2002
The role of the central nervous system in heatstroke: reversible profound depression of cerebral activity in a primate model.
The neurological manifestations of heatstroke victims vary. The exact sequence of the central nervous system (CNS) changes during lethal hyperthermia has only been partially explored, and the data covering the post-resuscitation CNS changes, which in most cases lead to secondary cardiac arrest, are insufficient. ⋯ The acute cerebral derangements during and after lethal hyperthermia are reversible. The cause of death is probably not CNS damage, but systemic hemodynamic deterioration.