Annals of emergency medicine
-
Randomized Controlled Trial Comparative Study
Core temperature cooling in healthy volunteers after rapid intravenous infusion of cold and room temperature saline solution.
Studies have suggested that inducing mild hypothermia improves neurologic outcomes after traumatic brain injury, major stroke, traumatic hemorrhage, and cardiac arrest. Although infusion of cold normal saline solution is a simple and inexpensive method for initiating hypothermia, human cold-defense mechanisms potentially make this route stressful or ineffective. We hypothesize that rapid infusion of 30 mL/kg of cold (4 degrees C, 39.2 degrees F) 0.9% saline solution during 30 minutes to healthy subjects (aged 27 [standard deviation (SD) 4] years) will reduce core body temperature to the therapeutic range of 33 degrees C to 35 degrees C (91.4 degrees F to 95 degrees F). ⋯ In this pilot study of healthy volunteers, rapid administration of cold saline solution to awake normothermic volunteers resulted in 1 degrees C (1.8 degrees F) cooling but did not induce a therapeutic plane of hypothermia. This change in core temperature was not accompanied by significant changes in skin temperature. These data suggest that a reduction in core temperature of about 1 degrees C (1.8 degrees F) can be achieved in healthy humans before a thermoregulatory response is triggered and that rapid infusion of cold intravenous fluids is insufficient by itself to overcome this response. The clinically relevant control arm of room temperature saline solution also resulted in mild core cooling.
-
In this article, we review published preclinical and epidemiologic studies that examine progesterone's role in the central nervous system. Its effects on the reproductive and endocrine systems are well known, but a large and growing body of evidence, including a recently published pilot clinical trial, indicates that the hormone also exerts neuroprotective effects on the central nervous system. We now know that it is produced in the brain, for the brain, by neurons and glial cells in the central and peripheral nervous system of both male and female individuals. ⋯ Although the research published to date has focused primarily on progesterone's effects on blunt traumatic brain injury, there is evidence that the hormone affords protection from several forms of acute central nervous system injury, including penetrating brain trauma, stroke, anoxic brain injury, and spinal cord injury. Progesterone appears to exert its protective effects by protecting or rebuilding the blood-brain barrier, decreasing development of cerebral edema, down-regulating the inflammatory cascade, and limiting cellular necrosis and apoptosis. All are plausible mechanisms of neuroprotection.
-
Practice Guideline
Clinical policy: Critical issues in the management of adult patients presenting to the emergency department with acute carbon monoxide poisoning.
This clinical policy focuses on critical issues concerning the management of adult patients presenting to the emergency department (ED) with acute symptomatic carbon monoxide (CO) poisoning. The subcommittee reviewed the medical literature relevant to the questions posed. ⋯ Level A recommendations represent patient management principles that reflect a high degree of clinical certainty; Level B recommendations represent patient management principles that reflect moderate clinical certainty; and Level C recommendations represent other patient management strategies that are based on preliminary, inconclusive, or conflicting evidence, or based on committee consensus. This clinical policy is intended for physicians working in hospital-based EDs.
-
Profound hypothermia is associated with high mortality and morbidity. Optimal outcomes have been reported with invasive extracorporeal warming techniques not readily available in most hospitals. Endovascular warming devices may provide a less invasive alternative. ⋯ An endovascular temperature control system was placed and effectively warmed the patient at about 3 degrees C (4.5 degrees F) per hour, with return of hemodynamic stability. When hypothermia is profound, surface warming works poorly and invasive strategies, including cardiopulmonary bypass, are recommended. Rapid warming from profound hypothermia can be accomplished with endovascular systems, and these may be an effective alternative to more invasive extracorporeal methods.
-
Therapeutic hypothermia is an exciting new treatment modality that has been shown to have significantly improved outcomes in comatose survivors of cardiac arrest. One of the exclusion criteria of the landmark studies on therapeutic hypothermia was a potential toxin-induced cause of the persistent comatose state and presumably of the cardiac arrest itself. We present the first reported case of a comatose survivor of cocaine-induced cardiac arrest successfully treated with therapeutic hypothermia.