Delayed medical emergency team calls and associated outcomes.

OBJECTIVE: To determine whether there was an association between delayed medical emergency team calls and mortality after a medical emergency team review. DESIGN: This was a prospective observational study. SETTING: A university-affiliated tertiary referral hospital in Porto Alegre, Brazil. PATIENTS: All patients were reviewed by the medical emergency team from July 2008 to December 2009. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: There were 1,481 calls for 1,148 patients. Delayed medical emergency team calls occurred for 246 patients (21.4%). The criterion associated with delay was typically the same criterion for the subsequent medical emergency team call. Physicians had a greater prevalence of delayed medical emergency team calls (110 of 246 [44.7%]) than timely medical emergency team calls (267 of 902 [29.6%]; p < 0.001). The mortality at 30 days after medical emergency team review was higher among patients with delayed medical emergency team activation (152 [61.8%]) than patients receiving timely medical emergency team activation (378 [41.9%]; p < 0.001). In a multivariate analysis, delayed medical emergency team calls remained significantly associated with higher mortality. CONCLUSIONS: Delayed medical emergency team calls are common and are independently associated with higher mortality. This result reaffirms the concept and need for a rapid response system.

[Effects of cimetidine on chronotropic response to cardiopulmonary exercise testing]. / Resposta cronotrópica ao teste cardiopulmonar após o uso de cimetidina.

OBJECTIVE: To test the hypothesis that the administration of cimetidine will modify the chronotropic response to exercise testing through a random clinical trial. METHODS: The study selected 24 eligible healthy subjects, ages between 20 and 68 years, not athletes, who agreed to undergo cardiopulmonary exercise testing after the administration of placebo and 400 mg of cimetidine twice a day for one week. The tests were performed on a treadmill using a ramp protocol and direct analysis of the expired gases. Peak, resting and anaerobic threshold heart rate were recorded. RESULTS: The twenty subjects studied were equally distributed across sex with mean (+/- SD) age 43 +/- 11 years. Tests on placebo and on cimetidine presented similar duration (578 +/- 90 sec vs 603 +/- 131 sec) and similar peak oxygen uptake (35 +/- 8 ml/kg.min vs 35 +/- 8 ml/kg.min). Cimetidine administration had no significant effect on resting heart rate (75 +/- 10 bpm vs 74 +/- 8 bpm), heart rate at peak exercise (176 +/- 12 bpm vs 176 +/- 11 bpm), and on the difference between the peak and the resting heart rates--delta HR (101 +/- 14 bpm vs 101 +/- 13 bpm). CONCLUSION: The administration of cimetidine for 7 days has no significant effect on the chronotropic response to exercise testing.

Resposta cronotrópica ao teste cardiopulmonar após o uso de cimetidina / Effects of cimetidine on chronotropic response to cardiopulmonary exercise testing

OBJETIVO: Testar a hipótese, por meio de ensaio clínico randomizado, de que a administração de cimetidina altera a resposta cronotrópica ao exercício. MÉTODOS: Foram selecionados 24 indivíduos saudáveis, com idade entre 20 e 68 anos, não-atletas, os quais concordaram em ser submetidos a testes cardiopulmonares, após uso de placebo e de cimetidina, 400 mg, duas vezes ao dia, durante uma semana. Os testes foram realizados em esteira rolante, com protocolo de rampa com análises diretas dos gases expirados. Foi avaliada freqüência cardíaca máxima atingida, além da freqüência cardíaca de repouso e do limiar anaeróbico. RESULTADOS: Os indivíduos estudados foram igualmente distribuídos por sexo, com idade média (± desvio padrão) de 43 ±11 anos. Os exames com placebo e com cimetidina tiveram igual duração (578±90 seg vs 603±131 seg) e igual VO2 pico (35±8 ml/kg.min vs 35±8 ml/kg.min). A administração de cimetidina não apresentou efeito significativo na freqüência cardíaca de repouso (75±10 vs 74±8 bpm), no pico do esforço (176±12 vs 176±11 bpm) e, da mesma forma, também não houve diferença entre as variações das freqüências cardíacas (pico - repouso), nos dois estudos (101±14 vs 101±13 bpm). CONCLUSÃO: A administração de cimetidina por sete dias não altera a resposta cronotrópica ao exercício.