| Autor: |
Jartti, T. T., Kaila, T. J., Tahvanainen, K. U. O., Kuusela, T. A., Vanto, T. T., Välimäki, I. A. T. |
| Předmět: |
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| Zdroj: |
European Journal of Pediatrics; 1997, Vol. 156 Issue 11, p883, 6p |
| Abstrakt: |
We studied the effects of therapeutic 2-week inhaled salbutamol treatment on the cardiovascular and respiratory autonomic nervous regulation in eight children with asthma. In this randomized, double-blind, placebo-controlled crossover study our test subjects inhaled 200 μg salbutamol or placebo thrice daily for 14 days. After the 14-day treatment we continuously measured electrocardiogram, finger systolic arterial pressure (SAP) and flow-volume spirometry at baseline and the response to a single 600 μg salbutamol inhalation. The periodic variability components of R-R intervals (the time between successive heart beats) and SAP in relation to respiration were assessed using spectral analysis. Two-week salbutamol treatment increased baseline low frequency (LF) variability (P<0.05) and low frequency/high frequency (LF/HF) variability ratio of R-R intervals (P<0.05) when compared to the placebo treatment. As a response to the single salbutamol inhalation the increase in LF/HF ratio of R-R intervals was smaller after the 2-week salbutamol treatment (P<0.01). No significant differences were found in the bronchodilatory response after the treatment period.Conclusion Two-week salbutamol treatment shifts the cardiovascular autonomic regulation to a new level characterized by greater sympathetic responsiveness and slight beta[sub 2] -receptor tolerance. Because these effects were evident 18 h after cessation of the therapy they are likely to reflect the adaptation of organ responses to regular therapy or altered central autonomic regulation rather than direct drug effect. A slight tolerance developed in the sympathovagal cardiac response but not in the bronchodilatory response. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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