A study of the sympathetic nervous system in bronchial asthma

Objective: To test sympathetic division of autonomic nervous system and observe any dysfunction in patients of bronchial asthma. Materials and Methods: Fifty four patients, 18 males, 36 females, and 30 healthy control subjects attending Respiratory Medicine out-patient department Regional Institute of Medical Sciences, Imphal were included in the study. Age ranging from 15 to 60 years were recruited for the study. Spirometry values of forced vital capacity (FVC), forced expiratory volume in first second (FEV 1 ) , FEV 1 /FVC, peak expiratory flow rate (PEFR), forced expiratory flow (FEF 25-75% ) recorded by using HELIOS 702 (Recorders and Medicare System, Chandigarh). Predicted values were taken as values for normal subjects. Sympathetic nervous system tested by measuring diastolic blood pressure response to sustained hand-grip for 2 min and from supine to standing for 3 min. Results: FVC, FEV 1 , PEFR, FEF 25-75% were significantly lower in asthmatics as compared to controls. Diastolic blood pressure response to sustained hand-grip for 2 min and from supine to standing for 3 min was higher in asthmatics as compared to controls. Conclusion: Sympathetic nervous function assessment of the patients shows that sympathetic abnormalities occur in patients of bronchial asthma.