AUTONOMIC CONTROL OF BRONCHIAL HYPERREACTIVITY IN OBSTRUCTIVE PULMONARY DISEASES
Author: VENKATACHALAM MADRAS, NAGASIREESHA CHALLA
Category: Physiology
Abstract:
Background: Any abnormality in autonomic regulation of the airways, may lead to bronchospasm, mucosal edema and excess secretion of mucus. This study was carried out to assess the bronchial hyper-reactivity in patients of bronchial asthma and chronic obstructive pulmonary disease (COPD) by exploring the status of sympathetic and parasympathetic division of autonomic nervous system by using simple and non-invasive autonomic function tests.
Aim: The aim was to assess and compare the bronchial hyper-reactivity in asthma and COPD with age related controls by autonomic function tests.
Materials and Methods: Twenty five asthmatics and 25 age related healthy control subjects, 25 COPD patients and 25 age related healthy controls attending the Chest outpatient department were included in the study. Baseline ventilatory functions like forced expired volume in 1 s(FEV1), forced vital capacity (FVC), FEV1/FVC ratio and percentage change in FEV1 after inhalations of salbutamol were recorded. Predicted values were taken as values for normal subjects. The parasympathetic tests i.e. postural tachycardia index (30:15), the valsalva maneuver, heart rate variation with deep respiration, and the sympathetic tests i.e. fall in systolic blood pressure (BP) on standing from the supine position, and diastolic BP response to a sustained hand grip were conducted.
Result: The present study shows a decline in FEV1 values in asthma and COPD with controls. The âtâ -test values of deep breathing difference and vasalva ratio in asthma is higher than in COPD. The parasympathetic stimulation is much intense in asthma than in COPD.
Conclusion: The sympathetic and basal parasympathetic tests did not show any difference between controls and patients but various maneuvers of parasympathetic stimulation showed significant hyperactivity in patients.
Keywords: Autonomic function tests, Bronchial asthma, Bronchial hyperactivity, Chronic obstructive pulmonary disease, Forced expired volume in 1 s.