• 1. Maintain adequate fluid balance
  • As a medical student and as a junior doctor, you will be busy and you will neglect your own needs sometimes. If you are dry, you are more likely to drop your blood pressure and feel faint. Keep well hydrated. Your urine should be light in colour and high in volume. In summary, keep peeing and stay vertical.
• 2. Look after your blood glucose levels.
  • Thinking of missing breakfast before the weekly consultant ward round? You’ll have only yourself to blame if you later feel dizzy and sweaty when the ward round gets particularly smelly.
• 3. Increase venous return
  • This is a common technique, taught to me by one of my senior students during junior surgery attachment. The idea is to push blood out of reserve areas whilst standing, which means tensing your calves, thighs and buttocks (in that order). An alternative way of achieving the same thing is to rock a few degrees forwards and backwards on the balls of your feet. This is effective and very discrete.
• 4. Escape, avoid, run away.

http://www.doceatdoc.com/howtopreventfainting/