Os efeitos da radiação diagnóstica / The effects of diagnostic radiation / Los efectos de la radiación diagnóstica

Após haver a exposição à bomba atômica no Japão, calcula-se que, em aproximadamente 100 mSv, a radiação produz danos no organismo, entre os quais estão os cânceres radioinduzidos. A radiação de diagnóstico tem uma categoria de dose abaixo de 100 mSv. Os efeitos da radiação a essas doses são baseados em estimativas; contudo, deve-se levar em consideração que as doses são acumulativas. Neste artigo, comenta-se sobre os riscos da radiação de diagnóstico e chama-se a atenção à racionalização do uso das pesquisas radiológicas e à aplicação dos critérios ALARA (as low as reasonably achievable).

After the exposition to the atomic bomb in Japan, it is calculated that over 100 mSv are the quantity of damage produced by radiation in the organism, among which it can be found radio induced cancers. The diagnostic radiation has a doses average that is below 100 mSv. The radiation effects to these doses are based on estimations; however, one should know that the doses are accumulative. In this article, diagnostic radiation risks are commented and it calls the attention to rationalizing the use of radiological explorations and to applying ALARA criteria.

Tras la exposición a la bomba atómica en Japón, se ha calculado que, por encima de 100 mSv, la radiación produce daños en el organismo, entre los que se encuentran los cánceres radioinducidos. La radiación diagnóstica tiene un rango de dosis que está por debajo de 100 mSv. Los efectos de la radiación a esta dosis se basan en estimaciones; sin embargo, hay que tener en cuenta que las dosis son acumulativas. En este artículo, se comentan los riesgos de la radiación diagnóstica y se hace una llamada de atención a la racionalización del uso de las exploraciones radiológicas y a la aplicación de los criterios ALARA (as low as reasonably achievable).

[Relationship between comorbidity and asthma control]. / Relación entre presencia de comorbilidad y control del asma.

INTRODUCTION: The coexistence of potentially aggravating processes is common in asthmatics, particularly in patients with difficult control. The primary aim of this study is to ascertain whether comorbidity id more common in uncontrolled patients. As a secondary aim, we propose to evaluate the correlation between the asthma control test (ACT) and the fraction of exhaled nitric oxide (FENO). PATIENT AND METHODS: A prospective, observational study comparing the function and clinical picture of two groups of asthmatics: controlled (ACT≥20) and uncontrolled (ACT<20). They were all assessed for, smoking, rhinosinusitis, obesity, anxiety, depression, vocal cord dysfunction, gastro-oesophageal reflux (GORD), allergic bronchopulmonary aspergillosis (ABPA), COPD and nasal polyps. RESULTS: A total of 50 patients with controlled asthma and 102 with suboptimal control were included. The patients with an ACT≥20 had better lung function, less variation in PEF, less bronchial hyper-reactivity and lower FENO values. Comorbidities were found in 95% of the controlled asthmatics and in 97% of the uncontrolled. Only the presence of nasal polyps, GORD and ABPA was more frequent in the uncontrolled group. However, the simultaneous presence of 3 or more comorbidity factors was significantly more frequent in patients with sub-optimal control (P=0.01). There was no significant correlation between the FENO and the ACT values (rho=-0.08; P=0.32). CONCLUSIONS: Aggravating comorbidities are more common in patients with sub-optimal control. There was no correlation between the FENO and the ACT values.

Clinical heterogeneity among patients with obesity hypoventilation syndrome: therapeutic implications.

BACKGROUND: Obesity hypoventilation syndrome (OHS) can be treated with noninvasive positive pressure ventilation (NIPPV). Once clinical stability is achieved, continuous positive airway pressure (CPAP) can be recommended in many cases. However, some patients respond only partially to CPAP and NIPPV is a better option for them. OBJECTIVES: To assess treatment effectiveness in 2 groups of patients: those who could be switched to CPAP after polysomnographic titration and those who required NIPPV. METHODS: A prospective study of 24 OHS patients was conducted, 11 were treated with CPAP and 13 with NIPPV. Morning and evening arterial blood gases were measured. Daytime and overnight oximetric recordings were performed. A post hoc analysis compared both groups. RESULTS: Neither group exhibited deterioration on morning-to-evening blood gases. All patients in the CPAP group presented SaO(2) of less than 90% (CT90%) for <15% of the time on nocturnal and daytime recordings. In the NIPPV group, 8 patients had either daytime or nocturnal CT90% >or=15%. There were no intergroup differences regarding age, body mass index, Epworth scale values or PaO(2)/PaCO(2) prior to treatment. FVC in the NIPPV group was lower than in the CPAP group (p = 0.01). Apnea-hypopnea index was higher (56 +/- 23 vs. 36 +/- 23, p = 0.049) and baseline CT90% was lower (76 +/- 19% vs. 92 +/- 14%, p = 0.03) in the CPAP group. CONCLUSIONS: Two patient subtypes can be identified. Those controlled with CPAP have better spirometry and a significantly higher apnea-hypopnea index. None of these patients showed daytime hypoxemia and all exhibited satisfactory overnight oxygenation. However, 61% of the NIPPV group had suboptimal oximetry results. Nocturnal/diurnal oximetries should be made to assess treatment efficacy in stable OHS patients who fail to achieve good control with CPAP.