Why did you pass out during the blood draw?
By pH health care professionals
Fainting – It can happen to otherwise healthy people! You may feel faint and lightheaded and then suddenly lose consciousness or pass out.
The most common cause of fainting (especially among children and young adults) is neurally mediated syncope, which is also commonly referred to as vasovagal syncope or a vasovagal response. In a vasovagal response, your blood pressure drops and the heart does not pump a normal amount of oxygen to the brain. The response is often triggered by anxiety or emotional distress, sometimes even from the sight of blood during a blood draw. This type of fainting can lead to minor injuries, like cuts or bruises from falling, but it is considered to be relatively harmless in most cases.
Before a vasovagal response, your skin may become pale, you may feel lightheaded, start to lose some vision (tunnel vision) and/or experience blurred vision. You may feel nausea, warmth or a cold sweat. You may even start yawning. Other people in the room may notice your pupils becoming dilated or notice you making jerky movements. You also might have a slow and weak pulse.
So what steps can you take to prevent fainting during your blood draw?
Tensing your muscles or crossing your legs at the onset of symptoms may help postpone or prevent fainting. You also may lie down and elevate your legs. If you have fainted at a blood draw before, you should ask to do your next blood draw lying down.
You can also reduce your likelihood of fainting by doing the following:
Try not to skip meals.
Don’t fast for too long.
Stay hydrated.
Avoid standing for prolonged periods of time.
Reduce caffeine and alcohol intake.
Try sleeping with your legs elevated.
Consider wearing elastic stockings to keep blood from pooling in your legs (which would reduce blood flow to your brain!).
Be proactive and talk to the nurse or phlebotomist before your blood draw and let him/her know if you have fainted before.
Enjoy Your Healthy Life!
