Effect of Head down Tilt on Cardiovascular Autonomic responses in males and females

The present study was done to evaluate the effect of Head Down Tilt (HDT) on Blood Pressure (BP) in males and females. The parameters which represent the cardiovascular autonomic function involved the Heart Rate (HR), Systolic Blood Pressure (SBP), Diastolic Blood Pressure (DBP), Mean Arterial Pressure (MAP) and Pulse Pressure (PP).

100 healthy males and females were selected. There was a limit in the age group from 18–45 years. The effect of HDT on cardiovascular autonomic responses was conducted in them. Parameters like HR and BP were recorded at supine and 30°, 60°, 80° HDT. In each position the HR was determined by recording the ECG for 5 min in lead II. Niviquire software was used. BP was measured within 20 seconds of the change in tilt position.

On HDT the HR, DBP, MAP, decreased. In contrast the SBP increased on HDT. These results were same in both males and females.

This study will help to know the cardiovascular autonomic differences in males and females. By conducting the HDT test it is easy for the medical students and the clinicians to understand and identify the cardiovascular reflex responses in healthy or diseased individuals.