Lynn J. White

A double-blind comparison between oral pseudoephedrine and topical oxymetazoline in the prevention of barotrauma during air travel

To determine the efficacy of two decongestants (oral pseudoephedrine versus topical oxymetazoline) in the prevention of middle ear barotrauma during air travel, 150 adult volunteers with a history of ear pain during air travel were entered into a randomized, double-blind study conducted at two commercial airports. Each subject received 120 mg pseudoephedrine, oxymetazoline hydrochloride (0.05%), or a double placebo (capsule and nasal spray) administered 30 minutes before flight departure. After arrival at their final destinations, volunteers were asked to complete a questionnaire and return it by mail to investigators. Questions included the intensity and duration of otologic symptoms experienced while flying and possible drug side effects. A total of 124 subjects completed the study; 41 received 120 mg of pseudoephedrine, 42 received oxymetazoline nasal spray, and 41 received a double placebo (capsule and nasal spray). The three treatment groups were similar with regard to age, sex, medical history, and flight profile. Symptoms of barotrauma were reported by 34% of those receiving pseudoephedrine versus 71% of the control group, for a relative risk reduction of 52% (95% confidence interval [CI] 33% to 71%). In contrast, 64% of the oxymetazoline group reported symptoms of barotrauma, for a relative risk reduction of 10% (95% CI, 3% to 17%). These results suggest that treatment with 120 mg pseudoephedrine at least 30 minutes before flying appears to decrease the incidence of barotrauma. Oxymetazoline nasal spray is little more effective than placebo in reducing ear pain and discomfort associated with changing ambient pressures.

National EMS research agenda: proceedings of the implementation symposium.

The National EMS Research Agenda identified eight recommendations for improving the conduct of emergency medical services (EMS) research in the United States. EMS leaders from across the country attended a two-day symposium to discuss implementation of the Research Agenda recommendations. The participants suggested specific methods to move the recommendations forward. These included improving training opportunities for EMS researchers, stimulating increases in available funding sources, facilitating the integration of research into practice, and crafting alterations within the regulatory environment. Participants felt that EMS must be more broadly integrated into the public health continuum. Federal agencies, states, local governments, charitable foundations, and corporations are asked to examine their practices to increase opportunities for participation in EMS research programs at all stages of the process.

Core temperature monitoring of firefighters during hazardous materials training sessions.

OBJECTIVE To determine core temperature (Tc) elevations in hazardous materials (HazMat) technicians wearing level-A fully encapsulated, chemically resistive suits (FECRSs) during training scenarios. DESIGN Cross-sectional, observational feasibility study with Institutional Review Board approval. SETTING HazMat training scenarios held during the summer of 1994. Weather conditions included both rainy and sunny days, with a mean ambient temperature of 75.8 degrees F (24.3 degrees C) (range 69-83 degrees F [20.6-28.3 degrees C). PARTICIPANTS Nine male firefighters participating in training scenarios in the Midwestern United States. INTERVENTIONS Each volunteer swallowed a capsule containing a Tc sensor developed by the National Aeronautics and Space Administration. The capsule continuously monitored Tc and stored data in an ambulatory recorder worn under the level-A FECRS during training. RESULTS Mean age of the volunteers was 34 years, mean weight was 92.6 kg, and average baseline Tc was 36.7 degrees C (97.1 degrees F) (range 35.3-38.2 degrees C [95.5-100 degrees F]). Time in the FECRS averaged 25.4 minutes (range 14-35 minutes). All subjects demonstrated increased Tc while in the suit; the mean Tc increase was 0.8 degree C (1.4 degrees F) (range 0.2-1.3 degrees C [0.4-2.3 degrees F]). The Tc continued to increase during wet decontamination procedures and after suit removal. Mean heat storage values (delta Tcx LBMx 3.47 kJ) were calculated, and found to be moderately elevated to 3.6 kJ/kg (range 2.1-4.6 kJ/kg). CONCLUSION These observations support the validity and significance of implementing prophylactic measures for firefighters using protective clothing. Simple protective measures include enforced time limitations, hydration, and efforts to minimize heat buildup by avoiding both direct sunlight and unnecessary time encapsulated in the suit.

Use of Amifostine, a Novel Cytoprotective, in α-Amanitin Poisoning

Background. Mortality from ingestions of the mushroom Amanita phalloides remains as high as 20–40% with many surviving patients requiring liver transplantation. A variety of treatments for Amanita ingestion have been evaluated, yet other than supportive measures, no effective therapy has been identified. In addition, an antidote for Amanita toxicity may not be practical due to delayed patient presentation. The drug amifostine was proposed to potentially improve survival from α-amanitin toxicity by conferring cytoprotective effects on hepatocytes at risk for cell death. Amifostine is used as a radio- and chemo-protective agent. It protects against lipoperoxidation, interferes with the cross-linking of DNA, and may act by other mechanisms yet to be identified, making it attractive for potentially attenuating ongoing hepatic necrosis. It has not previously been studied in a toxicologic model. Study Objective. To determine whether amifostine is an effective postexposure therapy for α-amanitin, the primary lethal toxin in Amanita phalloides. Methods. Swiss mice (n = 30 in all groups) were given an approximate LD75 dose of intraperitoneal (i.p.) α-amanitin. Amifostine was administered i.p. 6 h after poisoning in three cumulative dosing groups: 250 mg/kg; 500 mg/kg; and 1600 mg/kg. Controls received equal volumes of i.p. sterile 0.9% saline. Mice were monitored and time of death recorded. At day 7, survival was assumed and the remaining mice were euthanized. Qualitative histologic comparisons of hepatic and renal toxicity were performed. Results. At day 7, only 10% of the control mice survived. Survival in the amifostine 250, 500, and 1600 mg/kg groups was 20%, 20%, and 3%, respectively. No statistically significant differences were detected in Kaplan-Meier survival between the control group and those receiving 250 or 500 mg/kg; however, there was a statistically significant decrease in survival for the group receiving 1600 mg/kg (p = 0.0002). Conclusion. No survival benefit was seen with cumulative doses between 250 and 500 mg/kg; however, higher doses may result in subsequent toxicity and decreased survival.