Impact of climate variability on exercise-induced bronchospasm in adolescents living in a semi-arid region / Influência de alterações climáticas sobre a ocorrência do broncoespasmo induzido por exercício em adolescentes de uma região semiárida

ABSTRACT Objective: To examine the impact of climate variability on the occurrence of exercise-induced bronchospasm in the rainy and dry seasons of a Brazilian semi-arid region. Methods: This sample comprised 82 adolescents aged 15 to 18 years, who were submitted to exercise-induced bronchospasm assessment on a treadmill and outdoors, during the rainy and the dry season. Anthropometric variables, sexual maturity and forced expiratory volume in the first second were analyzed. Air temperature and humidity, decline in forced expiratory volume in the first second (%) and frequency of bronchospasm were compared between seasons using the independent Student's t test, the Wilcoxon and McNemar tests, respectively. The level of significance was set at p<0.05. Results: The mean age was 15.65±0.82 years. Air temperature, air humidity and decline in forced expiratory volume in the first second (%) differed between seasons, with higher air temperature and humidity in the rainy season (29.6ºC±0.1 and 70.8%±0.6 versus 28.5ºC±0.2 and 48.5%±0.6; p<0.05). The decline in forced expiratory volume in the first second (%) was greater in the dry season (9.43%±9.97 versus 12.94%±15.65; p<0.05). The frequency of bronchospasm did not differ between seasons. Conclusion: The dry season had a negative impact on forced expiratory volume in the first second in adolescents, with greater decrease detected during this period. Findings of this study suggested bronchospasm tends to be more severe under low humidity conditions.

RESUMO Objetivo: Verificar a influência das alterações climáticas sobre o broncoespasmo induzido por exercício, nos períodos chuvoso e seco de uma região do semiárido brasileiro. Métodos: Foram submetidos à avaliação do broncoespasmo em esteira ergométrica, em ambiente externo, nos períodos chuvoso e seco, 82 adolescentes, com idades de 15 a 18 anos. Foram avaliadas as variáveis antropométricas, a maturação sexual e o volume expiratório forçado no primeiro segundo. Para comparação da temperatura e umidade, queda do volume expiratório forçado no primeiro segundo (%) e frequência do broncoespasmo entre os períodos, foram utilizados o teste t de Student independente, o teste de Wilcoxon e o teste de McNemar, respectivamente. O nível de significância adotado foi p<0,05. Resultados: A média de idade foi 15,65±0,82 anos. A temperatura, a umidade e a queda do volume expiratório forçado no primeiro segundo (%) diferiram entre os períodos, com valores de temperatura e umidade maiores no período chuvoso (29,6ºC±0,1 e 70,8%±0,6 versus 28,5ºC±0,2 e 48,4%±0,6; p<0,05). A queda do volume expiratório forçado no primeiro segundo (%) foi maior no período seco (9,43%±9,97 versus 12,94%±15,65; p<0,05), e não foi encontrada diferença da frequência do broncoespasmo entre os períodos. Conclusão: O período seco influenciou negativamente no volume expiratório forçado no primeiro segundo de adolescentes, observando maior percentual de queda dessa variável nesse período. De acordo com os achados, propõe-se uma maior gravidade do broncoespasmo induzido por exercício em condições de baixa umidade.

Sensitivity and specificity of self-reported symptoms for exercise-induced bronchospasm diagnosis in children

Exercise-induced bronchospasm [EIB] is a common condition in elite athletes. The purpose of this study was to evaluate the diagnostic value of self-reported EIB symptoms in children. In a cross sectional study in 2005, all soccer player boys of 3 football schools of Shahr Rey a town in the south of Tehran, enrolled in this study. All subjects were asked for the presence of four cardinal symptoms of EIB [cough, wheeze, shortness of breath, chest pain/discomfort] during and after exercise. Self reported symptom-based EIB was defined as having at least two out of four symptoms. Findings were compared to spirometric criteria as a gold standard test. A total of 371 boys were enrolled in this study. The mean age of children was 11.67 +/- 1.53 years [range 7-16 years]. According to spirometric findings, 74 [19.9%] subjects had EIB. The sensitivity and specificity of self-reported symptoms for EIB diagnosis were 13.0% and 89.9%, respectively. Self-reported symptoms of EIB in children can be useful for epidemiological study. Our results in Iran are comparable with studies in other countries and point to a relatively high prevalence of EIB among athlete children

Prevalence du bronchospasme induit par l'exercice (BIE) dans un echantillon randomise de 73 recrues des Forces Armees Nationales de Cote d'Ivoire

OBJECTIFS: Afin de verifier l'hypothese selon laquelle le climat chaud et humide protegerait contres la survenue du bronchospasme induit par l'exercice (BIE); notre etude avait pour but de determiner la prevalence du BIE chez les recrues vivant et exercant sous un climat tropical humide comme celui de la Cote d'Ivoire. MATERIEL ET METHODE: Notre enquete prospective a visee epidemiologique etait de type transversal. Elle avait ete effectuee de juin 2001 a mars 2002 entre 7h30 et 12 h a une temperature ambiante et une humidite relative variant respectivement de 24 a 41oC et de 96 a 70pour cent. Elle avait concerne un echantillon randomise de 73 recrues issues des quatre ecoles de formation militaire des FANCI. Apres avoir repondu a un questionnaire auto administre; chaque recrue equipee d'un cardio-frequence metre; avait realise sans echauffement prealable une course libre sur terrain plat pendant 8 mn. Les parametres ventilatoires etaient evalues avant et immediatement apres l'effort; puis aux 3eme; 5eme; 10eme; 15eme; 20eme et 30eme minutes de la periode de recuperation. Le seuil de positivite du test etait fixe a 10pour cent de chute du VEMS post-exercice. RESULTATS: Selon le questionnaire; aucune des recrues n'etait asthmatique connue. En revanche; apres le test de provocation bronchique a l'effort; 15 recrues soit 20.50pour cent etaient diagnostiquees BIE positif alors que leurs parametres ventilatoires de repos etaient egaux a ceux des sujets BIE negatif La chute du VEMS post-exercice chez les recrues BIE positif apparaissait precocement dans les 15 premieres minutes de la periode de recuperation. COMMENTAIRES: Cette etude effectuee chez des recrues non asthmatiques vivant et exercant en zone tropicale humide; montrait une prevalence du BIE aussi elevee que celle de nombreuses etudes menees en climat froid et sec. Ce resultat n'etait donc pas en faveur du caractere protecteur de l'air chaud et humide contre la survenue du BlE tel que suggere par plusieurs auteurs

Broncospasmo durante la anestesia / Bronchospasm during anestesia

En esta revisión bibliográfica se presentan los factores que contribuyen a la hiperreactividad de las vías aéreas durante la anestesia. Se presenta una actualización de las acciones de los agentes anestésicos empleados en nuestro medio, así como el tratamiento utilizado en esta complicación. El objetivo fundamental es ofrecer a los anestesiólogos, los elementos necesarios para una mejor conducción anestésica de los pacientes con hiperreactividad de las vías aéreas. Se enfatiza además en la importancia de las medidas preventivas y en el tratamiento inmediato que permita contrarrestar esta complicación(AU)

Those factors contributing to hyperreactivity of the airways during anesthesia are presented in this bibliographic review. An updating is made of the action of the anesthetics used in our setting and the treatment given to this complication is explained. The main objective is to provide anesthesiologists with the necessary elements for a better anesthetic conduction of the patients with hyperreactivity of the airways. It is underlined the importance of taking preventive actions and of immediate treatment to face this complication(AU)