Effects of two nebulization regimens on heart rate variability during acute asthma exacerbations in children.
Analysis of heart rate variability (HRV) has been used to evaluate changes in sympathovagal balance. The present study was designed to investigate the influence of two therapeutic regimens on autonomic cardiovascular regulation during acute asthma exacerbations (AAE). Twenty children, 7-13 years of age, with moderate or severe AAE were randomized in two equal groups to receive either 0.15 mg/kg/dose salbutamol (group 1) or a combination of lower-dose salbutamol (0.10 mg/kg/dose) and ipratropium bromide (5 mcg/kg/dose) (group 2). Exacerbations were treated with three nebulizations (Tx) of either regimen given 20 minutes apart. HRV indices [total power, high-frequency component (HF), low-frequency component (LF), and LF:HF ratio] were analyzed at specific time intervals during the management of AAE. Therapy had a significant time-dependent main effect on total power (p = 0.001), LF (p < 0.0001), and HF (p = 0.005) but reached only borderline significance for LF:HF ratio (p = 0.053). The decrease in LF was more pronounced in group 2 vs. group 1 at 10 minutes post-Tx1 (p = 0.034) and at 10 minutes post-Tx2 (p = 0.05), but there was no significant difference between groups at 10 and 20 minutes post-Tx3. There were no significant differences between groups in any of the other HRV indices. Both regimens improved FEV1 (p = 0.0001) to the same magnitude. During AAE, three consecutive inhalation treatments with either high-dose salbutamol-only or lower-dose salbutamol plus ipratropium bromide combination, resulting in similar FEV1 improvement, cause domination of sympathetic over parasympathetic nervous system of similar overall magnitude but distinct patterns of HRV indices.
Anthracopoulos
Michael B
MB
Department of Pediatrics, Respiratory Unit, University of Patras, Rio, Patras, Greece. manthra@otenet.gr
Karatza
Ageliki A
AA
Davlouros
Periklis A
PA
Chiladakis
John A
JA
Manolis
Antonis S
AS
Beratis
Nicholas G
NG
D000208:Acute Disease; D000280:Administration, Inhalation; D000293:Adolescent; D000318:Adrenergic beta-Agonists / Q000494:pharmacology; D000420:Albuterol / Q000494:pharmacology*; D001249:Asthma / Q000188:drug therapy* / Q000503:physiopathology; D002648:Child; D018680:Cholinergic Antagonists / Q000494:pharmacology; D004334:Drug Administration Schedule; D005260:Female; D006339:Heart Rate / Q000187:drug effects*; D006801:Humans; D009241:Ipratropium / Q000494:pharmacology*; D008297:Male; D009330:Nebulizers and Vaporizers; D012123:Pulmonary Ventilation / Q000187:drug effects; D012720:Severity of Illness Index; D016896:Treatment Outcome
D000318:Adrenergic beta-Agonists; D018680:Cholinergic Antagonists; D009241:Ipratropium; D000420:Albuterol