Peak expiratory flow rate values of students in Bangkok.

BACKGROUND: As there are considerable variations in normal values of peak expiratory flow rate (PEFR) shown by studies from various population, a study is required to obtain normal values of PEFR in Thai children. OBJECTIVE: To determine the values of PEFR of students in Bangkok. METHODS: In a cross sectional study of PEFR measured with standard Wright peak flow meter, 501 normal students, aged 5 to 15 years, from five public schools in Bangkok were investigated. In the selection process of subjects, strict criteria of "normality" were applied and included history of medical illnesses, physical examination and nutritional status. RESULTS: The relationship between PEFR and height was approximately linear in both male and female children. Prediction equations for each sex were: Male children: PEFR (L/min) = [3.52 x Height (cm)] - 186.80 Female children: PEFR (L/min) = [3.48 x Height (cm)] - 204.11 The PEFR values of students in this study were different from the predicted values of PEFR in those of previous reports in Thai children. These discrepancies might be explained by a variety of study population and environmental factors. CONCLUSIONS: The relationship between PEFR and height of students in Bangkok is best described by a regression equation. The prediction graphs for each sex may be used to monitor PEFR values of children with obstructive airway diseases and to compare an individual's PEFR with those of others of the same height and sex.

Fluticasone propionate and bronchial hyperresponsiveness in childhood asthma.

Bronchial asthma is now agreed as being a chronic inflammatory disease of the airways. Inhaled steroids are widely accepted as a preventive medication in asthmatic patients of all ages and severity. However, the optimal use of inhaled steroids and the important issue of safety and efficacy still remain of concern, particularly in children. Recently, fluticasone propionate (FP) has been developed for use as an inhaled preparation for the treatment of asthma. Because of its high topical potency and increased lipophilicity, it is claimed that FP has an improved risk/benefit compared with other inhaled steroids. In order to evaluate the use of FP in children, we have studied the efficacy of high dose FP (500 microg/day) in asthmatic children. Thirteen children (9 boys and 4 girls), aged 7-17 years (10.8 +/- 2.6), were instructed to use a pressurized metered-dose inhaler connected to a Volumetric spacer. The standard methacholine bronchial challenge test was used as a principal outcome parameter. The PD20, a cumulative dose of methacholine inducing a 20% decrease in FEV1, was measured pre- and post-treatment with inhaled FP. After 4 weeks of FP, PD20 significantly increased from 21.6 +/- 14.3 inhalation unit to 106.6 +/- 78.5 inhalation unit (4.9 fold, p = 0.004) reflecting the improvement of airway reactivity. All subjects improved clinically. These results demonstrate that the anti-inflammatory action of FP 500 microg a day for four weeks can markedly reduce bronchial hyperresponsiveness, the basic physiologic abnormality in bronchial asthma.

Aeroallergen in Thai asthmatic children.

Intradermal skin-teat reactions in 521 Thai asthmatic children (345 males and 176 females), aged between 3 and 15 years, with an average age of 6.8, were studied at the allergy clinic of Ramathibodi Hospital. Of the total, 456 (87 per cent) patients gave positive immediate skin reaction at least one “common aeroallergen”. The mist commonly seen aeroallergens were house dust (75 per cent) and house dust mite (73 per cent), followed by mold (55 per cent), grass ( per cent), weed (43 per cent), kapox (41 per cent) and cockroach (18 per cent). The finding of this study was that the most important aeroallergens were house dust and house dust mites which was similar to the results previously found in similar studies.

Incorrect use of metered dose inhaler by pediatric residents.

Currently press-and-breath metered dose inhalers (MDIs) are widely prescribed but are often difficult for many patients to properly use. However many medical personnel cannot use the MDIs correctly. We administered a question and observed usage of a placebo metered dose inhaler with ad-on spacer (Nebuhaler) among 127 second year pediatric residents. Forty-eight per cent of the residents performed at least six of nine steps correctly. The two most common errors made by participants were not to place mouthpiece tightly between teeth and lips (64%) and failure to breath out to functional residual capacity before actuation (55.3%). Of the residents with improper timing of actuation (49%) all actuated the canister before starting inhalation. (5 seconds or longer time). We conclude that (1) pediatricians should have additional instruction in proper MDIs usage and practice with the asthmatic child and (2) routine assessment of MDIs technique should be instituted as standard practice care.

A comparison of different intervals of administration of inhaled terbutaline in children with acute asthma.

Thirty asthmatic children, 5 to 14 years of age, 20 boys and 10 girls, were studied while having acute asthmatic attacks. Each group of 10 children received either a single dose of 6 puffs (1500 micrograms) or 3 doses of 2 puffs (500 micrograms) at 5-minute or 15-minute intervals of terbutaline pressurized aerosol inhaler through a 750-ml volumetric spacer. The onset of bronchodilatation was observed within 2 minutes in all. The 3 doses at 15-minute intervals gave the greatest bronchodilatation throughout the 6-hour study period in comparing with the other two regimens. Slightly insignificant increases in systolic blood pressure and heart rate were observed in all groups and there were no statistically significant differences among them. No serious side effects were observed.

Comparison of inhaled terbutaline and inhaled terbutaline plus ipratropium bromide in acute asthmatic children.

Twenty asthmatic children, aged 4 to 15 years, consisting of 14 boys and 6 girls, were studied during acute episodes of asthmatic attacks. A group of 10 children each received either inhaled terbutaline 0.5 mg or inhaled terbutaline 0.5 mg followed by ipratropium bromide 0.04 mg 15 minutes later through a 750-ml volumetric spacer. Significant increases in FEV1 over the baseline were observed from 2 minutes to 2 hours and from 2 minutes to 6 hours following the first and second regimen respectively. A slightly greater increase and longer duration in FEV1 were observed in the combined drug treatment and very slight decreases in systolic and diastolic blood pressure below the base-line were observed. Neither regimen showed any serious adverse effect on the heart rate and respiratory rate.

Atmospheric pollen and mold spores in Bangkok: a 15 year survey.

A 15-year survey of atmospheric pollen and mold spores was carried out in Bangkok, Thailand, from January 1973 to December 1987 by Durham's standard gravity slide sampler. The pollen and mold spore counts were presented. The peak of the pollen and mold spores occurred during the time of the year with lower average temperature, relative humidity and rain-fall. For pollen, this was from November to January and for mold spores from December to February. Mold spores of the Class Fungi Imperfecti were predominant and most likely the major fungi in mold allergy. Grass was the principal air-borne pollen.

Comparison of inhaled terbutaline and terbutaline injection in treatment of acute asthmatic attacks in children.

Thirty asthmatic children, aged 4 to 13 years, 22 boys and 8 girls, were studied during acute asthmatic attacks. Each group of 15 children received either a 0.01 mg/kg subcutaneous injection of terbutaline or 2 puffs from terbutaline pressurized aerosol (0.25 mg/puff) inhaler through a 750-ml volumetric spacer. A slightly greater increase in PEFR following injection compared with inhalation throughout the 6 hours study period was observed. Significant increases in systolic blood pressure and pulse rate were observed only after injection. Therefore, it was concluded that inhaled terbutaline is safe and effective for treating children over 4 years of age with acute bronchospasm and has less cardiovascular side effects than injected terbutaline.