Cold water immersion: kill or cure?

NEW FINDINGS: What is the topic of this review? This is the first review to look across the broad field of 'cold water immersion' and to determine the threats and benefits associated with it as both a hazard and a treatment. What advances does it highlight? The level of evidence supporting each of the areas reviewed is assessed. Like other environmental constituents, such as pressure, heat and oxygen, cold water can be either good or bad, threat or treatment, depending on circumstance. Given the current increase in the popularly of open cold water swimming, it is timely to review the various human responses to cold water immersion (CWI) and consider the strength of the claims made for the effects of CWI. As a consequence, in this review we look at the history of CWI and examine CWI as a precursor to drowning, cardiac arrest and hypothermia. We also assess its role in prolonged survival underwater, extending exercise time in the heat and treating hyperthermic casualties. More recent uses, such as in the prevention of inflammation and treatment of inflammation-related conditions, are also considered. It is concluded that the evidence base for the different claims made for CWI are varied, and although in most instances there seems to be a credible rationale for the benefits or otherwise of CWI, in some instances the supporting data remain at the level of anecdotal speculation. Clear directions and requirements for future research are indicated by this review.

Diagnosis and management of environmental thoracic emergencies.

Physiologic sequelae from increasing ambient pressure in underwater activities, decreasing ambient pressure while at altitude, or the consequences of drowning present a unique set of challenges to emergency physicians. In addition, several environmental toxins cause significant respiratory morbidity, whether they be pulmonary irritants, simple asphyxiants, or systemic toxins. It is important for emergency physicians to understand the pathophysiology of these illnesses as well as to apply this knowledge to the clinical arena either in the prehospital setting or in the emergency department. Current treatment paradigms and controversies within these regimens are discussed.

Use of the infant transwarmer mattress as an external warming modality in resuscitation from hypothermia.

Normothermia must be established in drowning victims before death may be declared, as the myocardium may remain resistant to stimulation at subnormal temperatures, and complete neurological recovery from submersion associated hypothermia has been reported. A safe and effective method of external re-warming is described that may prove particularly useful in the paediatric population.

The physiological effects of Aralia, Panax and Eleutherococcus on exercised rats.

Relative and total amount of saponins in Panax ginseng, Panax quinquefolius, Aralia mandshurica and Eleutherococcus senticosus were determined by thin-layer chromatography and by a spectrophotometric method. The ginsenoside Rg1 was present in American ginseng. Aralia and Eleutherococcus did not contain diol- and triol-type ginsenosides. Low concentrations of ginsenosides were found in Oriental red ginsengs (1.4-2.7%). Orally administered Araliaceae saponin extracts did not affect plasma lactic acid, glucagon, insulin or liver glycogen levels in exercised rats and did not prolong their swimming time. Plasma glucose levels in resting rats were decreased by saponin extracts of Canadian white, American red, Sanchi, Aralia, Eleutherococcus, Korean red and Shiu-Chi ginsengs.