ABSTRACT
BACKGROUND@#A definite diagnosis of asthma during infancy is difficult. Asthma Predictive Index (API) is used to predict asthma at school age, but does not determine who among these actually have asthma.@*OBJECTIVES@#This study aims to determine the bronchodilator response of infants with recurrent wheezing compared with normal control.@*METHODOLOGY@#This cross sectional study included asymptomatic subjects aged 6-24 months with history of recurrent wheezing and age/sex matched controls. After sedation with chloral hydrate (Odan) at 50-75 mg/kg, a bronchodilator challenge test was performed with single dose 400 mcg salbutamol (Ventolin) MDI inhalation delivered via a spacer (Philips Respironic OptiChamber Diamond). Baseline and 15 minutes after salbutamol inhalation Maximum Flow at Functional Residual Capacity (V‘maxFRC) were determined using MasterScreen Paed/BabyBody Option Squeeze version 8.0. ANOVA and Pearson chi-square were used for the statistical analysis of data.@*RESULTS@#Sixty-nine infants (23 previous wheezers and positive API, 23 previous wheezers with negative API and 23 controls) were included. There was a significant difference in the post bronchodilator challenge test V‘maxFRC between wheezers with positive API and controls (p= 0.047). There was no significant difference in other parameter among groups.@*CONCLUSION AND RECOMMENDATION@#Absolute values of V‘maxFRC post bronchodilator challenge using the Tidal Rapid Thoracoabdominal compression technique may be used to identify current asthma among asymptomatic infants with recurrent wheezing. Further studies with patient follow-up are recommended to assess response to treatment.
ABSTRACT
@#<p style="text-align: justify;"><strong>BACKGROUND:</strong> The diagnosis of asthma is difficult to establish using spirometry in children below 5 years old. Tidal breathing analysis (TBA) can provide useful information about lung function in infants and young children, as it is effort-independent. </p><p style="text-align: justify;"><strong>OBJECTIVES:</strong> To determine if baseline and post-bronchodilator ratios of the time and volume until peak expiratory flow to the total expiratory time and volume, (tPEF/tE and V PEF/V E) can distinguish asthmatics from normal children.</p><p style="text-align: justify;"><strong>METHODS:</strong> This is a cross-sectional study wherein 146 children ages 6 months to 5 years old completed TBA before and 15 minutes after administration of 250?g of salbutamol via nebulization. Children 3 years old and below who did not cooperate were given sedation with oral diphenhydramine (1mg/kg/dose). The tPEF/tE and VPEF/VE were compared between the controls and asthmatics.</p><p style="text-align: justify;"><strong>RESULTS:</strong> In children below 2 years old, the baseline tPEF/tE of asthmatics and non-asthmatics were 29.6 ± 13.8and 22.0 ± 6.6. The area under the curve (AUC) was 0.649 attPEF/tEof 32.250, with a sensitivity and specificity of 50% and 97%. The baseline VPEF/VE of asthmatics and non-asthmatics were 32.7 ±12.4 and 26.0 ± 4.9.AUC was 0.661 at VPEF/VEof34.500, with a sensitivity and specificity of 50% and 97%.In subjects 2 to 5 years old, the baseline tPEF/tE of asthmatics and non-asthmatics were 35.3 ± 14.7 and 35.0 ± 13.1. The baseline VPEF/VE were 37.0 ± 12.3 and 36.7 ± 10.7. After salbutamol nebulization, the tPEF/tE of asthmatics and non-asthmatics in all ages were 30.9±13.7 and 27.9± 10.8. The VPEF/VE were 34.1± 11.4 and 30.9± 9.0.</p><p style="text-align: justify;"><strong>CONCLUSION</strong>: Baseline tPEF/tE and VPEF/VE can distinguish asthmatics from non-asthmatics in children below 2 years old. However, baseline tPEF/tE and VPEF/VE in children 2 to 5 years old and post-bronchodilator tPEF/tE and VPEF/VE in all ages could not distinguish asthmatics from non-asthmatics after nebulization with 250?g of salbutamol.</p>