Objectives: It has been shown that human clinical trials that lack randomization (RND) or blinding (BLD) often overestimate the magnitude of treatment effects. However, no studies have evaluated the effect of RND and BLD on animal research. The authors' objectives were to determine the proportion of animal studies presented at a national academic emergency medicine meeting that utilize randomization, blinding, or both; and to determine whether failure to employ these techniques changes the likelihood of observing a difference between treatment groups. Methods: Two trained researchers reviewed abstracts presented at the 1997-2001 Society for Academic Emergency Medicine (SAEM) annual meetings using a standard data collection sheet. Studies that used an animal or cell line, compared two or more study groups, and measured an effect caused by the intervention or drugs were included. Studies were classified as randomized (RNDþ) if any part of the experiment involved random assignment of subjects to treatment groups, blinded (BLDþ) if any assessment of the outcome was made by an investigator blinded to treatment group, and outcome-positive (Outcomeþ) if any difference between the study groups met the author's definition of significant. Following the initial review, differences in classification were resolved by consensus. The association between outcome and study methodology (RND, BLD or both) was measured using odds ratios (ORs) with 95% confidence intervals (95% CIs). Results: A total of 2,592 studies were published as abstracts. Three hundred eighty-nine were animal studies, and 290 of these studies had two or more study groups. RNDÿ and BLDÿ studies were more likely to be Outcomeþ than RNDþ or BLDþ studies (OR ¼ 3.4; 95% CI ¼ 1.7 to 6.9 and OR ¼ 3.2; 95% CI ¼ 1.3 to 7.7, respectively). When studies that used both RND and BND were compared with studies that used neither, the OR for a positive study was 5.2 (95% CI ¼ 2.0 to 13.5). Conclusions: These results suggest that animal studies that do not utilize RND and BLD are more likely to report a difference between study groups than studies that employ these methods.

E xercise-associated hyponatremia (EAH) can occur during or up to 24 hours after prolonged exertion. 3,8 It is one of the most important medical problems in endurance events such as marathons, triathlons, and ultra-endurance events. 5,7,8 CASE REPORTA 44-year-old man presented to the emergency department (ED) with increased thirst, nausea, and shakiness 6 hours after completing a 100-mile mountain bike race in Leadville, Colorado, in August. The course altitude ranges from 2,804 to 3,840 m. He finished the race just under the 12-hour cutoff time. This was his first attempt in completing this race. He does participate in long-distance mountain bike races, but never had previous symptoms such as leg cramping and dizziness as he had during the last 2 hours of this race. He had been dealing with cramping 2 months prior, which typically manifested after 5 to 6 hours of riding. He did not visit any of the aid stations during the race. He had 3 episodes of mild diarrhea the day before the race and denied any vomiting, black stools, or difficulty urinating during the race. He reported normal color urination at least 2 to 3 times during the race. The average temperature and humidity were 13.9ºC (3ºC-25ºC) and 42% (13%-71%), respectively, on race day. He drank approximately 15,550 mL of water and 7100 mL of electrolyte fluid (approximately 2.8 g of sodium) plus 10 salt tablets (approximately 1.9 g of sodium) during the race. He felt very thirsty after the race and had half of a burger with a few French fries and a few sips of beer for dinner. Then, he drove with his wife back to Denver (a 2-hour drive). He had another 6750 mL of water and 0.55 g of salt after completing the race before going to the ED. Thus, he ingested roughly 29 L of water and 5.25 g of sodium during and after the race. His wife took him to the ED because of his continuous nausea and shakiness.Past medical history was positive for exertional cramping with training. He was not taking any medications on a regular basis. He denied taking any nonsteroidal anti-inflammatory drugs (NSAIDs) during the race but took 400 mg of ibuprofen afterward for back soreness. His vital signs were unremarkable with weight of 83.9 kg and height of 175.3 cm (body mass index, 27 kg/m 2 ). He appeared alert, anxious, and in mild distress. Other than a slight confusion on his arrival to the ED, there was no alteration in mental status with no motor or sensory deficit. Otherwise, his neurological and remaining physical examinations, including respiratory, were unremarkable.Initial laboratory tests in the ED included: sodium 116 mEq/L, glucose 102 mg/dL, phosphorus 2.4 mg/dL, magnesium 1.6 mg/dL, TSH 1.8 microIU/mL, urine osmolality 115 mOsm/kg, serum osmolality 249 mOsm/kg, urine sodium 31 mEq/L, Exercise-Associated Hyponatremia in an Ultra-Endurance Mountain Biker: A Case Report Morteza Khodaee, MD, MPH,* † Dylan Luyten, MD, ‡ and Tamara Hew-Butler, DPM, PhD § Symptomatic exercise-associated hyponatremia (EAH), which is relatively common among marathon runners, is an uncommon e...

Objectives The annual incidence of out-of-hospital cardiac arrest (CA) in the United States is approximately 6 per 10,000 population and survival remains low. Relatively little is known about the performance characteristics of a two-tiered EMS system split between fire-based basic life support dispersed from fixed locations and hospital-based advanced life support dispersed from non-fixed locations. The objectives of this study were to, therefore, describe the incidence of CA in Denver, Colorado and to define the prevalence of survival with good neurological function in the context of this EMS system. Methods Setting: A two-tiered hospital-based EMS system for the County of Denver, and 10 receiving hospitals. Population: Consecutive adult patients who experienced non-traumatic out-of-hospital CA from January 1, 2003 through December 31, 2004. Design: Retrospective cohort study using standardized abstraction methodology. Data Collection: Demographic and prehospital arrest characteristics and treatment data, and survival data using the Utstein template. Outcome: Good neurologic survival defined by a Cerebral Performance Category (CPC) Score of 1 or 2. Results During the study period, 1,985 arrests occurred. Of these, 715 (36%) had attempted resuscitation by paramedics and constitute our study sample. The median age was 65 (IQR: 52–78) years, 69% were male, 41% had witnessed arrest, 25% had bystander CPR performed, and 30% had VF or pulseless VT as their initial rhythm. Of the 715 patients, 545 (76%) were transported to a hospital, 223 (31%) had return of spontaneous circulation, 175 (25%) survived to hospital admission, 58 (8%) survived to hospital discharge, and 42 (6%, 95% CI: 4%–8%) had a good neurologic outcome. Conclusions Out-of-hospital CA survival in Denver, Colorado is similar to other United States communities.

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