Thursday, May 08, 2008

Post-vaccination syncope

Early in my medical school career, some brave pediatrician rounded up a group of us to observe a circumcision. The mom among us (brave soul had a young son at home) turned white as a sheet mid-procedure and sank to the floor in a faint.

This loss of consciousness as a result of undergoing an unpleasant experience is called vasovagal syncope. Completely involuntary, changes in automatic body functions after an intense experience result in overactivation of the parasympathetic nervous system (drop in heart rate) and withdrawal of sympathetic tone (dilation of blood vessels with a subsequent drop in blood pressure). Blood flow to the head diminishes (thus white face), and down she goes.

Actually, she is not completely accurate. The most common vasovagal reactions we see at the office are young men swooning after blood draws. Per the May 2nd Morbidity and Mortality Weekly Report, however, there's a new trend in fainting--teenage girls going to ground after vaccinations.

Experts theorize that the upswing in adolescent girls getting shots due to the rise in recommended vaccines such as the Gardasil series against HPV has caused this surge in syncope. While sinking to a prone position restores blood flow to brain, the worry here is that the young lady will injure herself while sinking, or will take out others if she sinks and drives.

Last year, one of my neighbors, a girl of 15, came to my office from her nearby school to get her tetanus shot. No one likes to be needled, but K was particularly dramatic about her distaste for the task. Nevertheless, she finally received her shot, and fifteen minutes later, we headed for my car as I was done with work and had offered to take her home. Halfway there, K complained of dizziness, and when I looked over she was out like a lightbulb, twenty-some minutes post-vaccine.

Our experience underlines the importance of the Advisory Committee on Immunization Practices' (ACIP) recommendation: Keep the drama mamas and the papas under observation for 15 or more minutes after they twitch their way through their ordeal.

10 comments:

Reality Man said...

Here's one for you, Dr. House-wife. In a class in Denmark, your niece had a real-life case study. A young woman in excellent physical condition, a six times a week exerciser, was going down unpredictably to the extent she could no longer work. The class was given the hint it was not hormonal.

JeanMac said...

Weird how needles bug some people, not others.I volunteered at a blood clinic and saw males faint, never a female in my short exp. there.

Cilicious said...

heh
Years ago, I was in the waiting room with my pet. I heard a loud thud in the examination room. Turns out a young guy, who'd brought in his dog for some minor procedure, had assured the doc he'd be okay staying in the room, them promptly went down the instant he saw blood.

denverdoc said...

Oh boy, just like House.

I suspect this is a multi-factorial faint. She probably has a slow heart beat and low blood pressure for starters as she is a well-conditioned athlete. She may have runner's anemia and an eating disorder.

Put all those together, she's already on the verge of fainting. Then she wears tight clothing, restricting blood return from the legs, and poof! no blood to brain and down she goes.

Reality Man said...

Right on on the low blood pressure and heart beat. I somehow forgot, and therefore did not mention, that she had stopped exercising when she began to show symptoms, but that does not mean that she was not still in excellent shape. Your niece writes: "heart nerve problem as it turns out."

denverdoc said...

Her heart took a 'vagus vacaton!'

Dreaming again said...

Needle phobic here ...although I got over fainting while pregnant and having the glucose tolerance test.
My needle phobia is not helped by it taking 5 or 6 pokes each time they need to draw blood. IV's are worse. (and, I've had monthly lab work for 16 years ... I haven't done the math on the number of sticks cause then I would faint)
Only about 1 or 2 months out of the year do they actually get me on the first stick.
It doesn't help that I have a cyst on one arm and so they only have one arm to draw from ...

Ok ... fainting mom ... here's one for you ... My son was hospitalized, very ill at 16 days old. Pnumonia and strep throat. My first child. My idea of hospitals at that time was ...you went to the hospital to either have surgery or you were dying. I never knew someone going to the hospital to get treatment. So obviously, I was rather panicked.
They put the blood pressure cuff on him, and got about 3 squeezes on him and down I went.
Obviously, they removed me from the room before putting in the IV's (yes, plural)

With 2 immune deficient kids & my health issues my perspective of hospitals changed. My ability to handle them messing with my grew a bit ...although, the spinal tap I didn't tolerate well. Stitches ...nuh huh. My son handled it well ... he told the doctor knock knock jokes. (no local ..said the local hurt more than the stitches ... I am the one who fainted.)

My neuro loves me *rolling eyes*

Anonymous said...

As a young runner in highschool I experienced similar problems with the addition of seizure activity when introduced to pain or shots, got my drivers license ganked as I went through my barrage of tests to find the problem. After my EEG's and EKG's finally got a cardiologist that labeled me with vasovagal syndrome and a "lazy" runner heart that wouldn't increase in heart rate with stress, but expand more to make up the volume... Got put on a high salt diet to increase my resting heart rate and BP... To this day have issues when in "too" good of shape with too low of a BP and HR.

Anonymous said...

My twin sons, age 14, faint and convulse after immunizations; recently, both went down within a few minutes of each other after getting flu shots in a pharmacy.

Neither has ever shown a fear of needles or blood and neither ever had problems with reactions to immunizations until they reached puberty. I wonder if there is research into the correlation of puberty and the frequency of vaso-vagal syncope episodes...

Anonymous said...

This happened to my 3-year old daughter today after her MMR vaccine. She'd just had a finger prick, handled it like a champ. No fighting the vaccine, she hardly even understood what was coming. A few minutes later, she slumped over in my arms and lost control of her bladder. She was not being a drama mama, so please keep that in mind. It seems like all patients should be made to sit down for 15 minutes after receiving a vaccine just to make sure no one is passing out and falling to the floor. I didn't know this was even a concern, but luckily I had her in my arms.