Haemodynamic effects of noise exposure before and after beta 1-selective and non-selective beta-adrenoceptor blockade in patients with essential hypertension

Abstract

1. Noise stimulation (100 dBA) for 10 min caused a significant increase in diastolic (7.0%, P less than 0.001) and mean arterial blood pressure (4.3%, P less than 0.01) in patients with essential hypertension. 2. The blood pressure response to noise was due to an increase in total peripheral resistance (4.8%, P less than 0.02); heart rate, stroke volume and cardiac output were unchanged. 3. beta 1-selective adrenoceptor blockade (metoprolol) did not change the haemodynamic reaction pattern induced by noise. 4. Noise exposure during non-selective beta-adrenoceptor blockade (propranolol) caused an accentuated blood pressure response with increments of both systolic and diastolic blood pressure as well as a more pronounced rise in total peripheral resistance. 5. The haemodynamic changes induced by noise stimulation at 100 dBA totally disappeared after 5 min of quiet rest at 40 dBA.