8.30.2008

FMOE, OB: Shoulder Dystocia

This is the second in a series called FMOE, which stands for For My Own Edification. Read on, but the post may be boring to anyone past an Intern, as I'm doing these to further my learning.

Coming off of OB, the next few will likely have something to do with pregnant women, who are total rock stars in my book, none more than my wife who has done things I would never have been able to do even if I had been born a woman. Too much of a wimp.

Shoulder dystocia (greek, dys for difficult plus tokos for birth) describes the failure of the shoulder to pass below the pubic symphysis during a spontaneous vaginal delivery with the head already delivered. In practical terms this is terrifying. The largest baby I delivered was 9 pounds, 12 ounces, and I had to pull like, a lot more than I expected to get her out despite excellent work by mom. It's scary when the baby feels stuck and you are hauling on its head. Normal deliveries require much more traction than you expect as a neophyte.

A truly stuck baby can have a severe shoulder injury or can asphyxiate and die. Badness, terrible badness. It's also hard to predict. If I had a 400 pound diabetic primigravid at post-dates in my ER delivering, I could say it's a good bet, but other than that, it can surprise anyone. What, oh what, to do?

Initial maneuvers. Of course, delivering the anterior shoulder requires a great deal of downward traction normally, so as a newbie, I have to remember to have may cardinal movements right; down for the anterior shoulder, up to the ceiling for the posterior. Simple suprapubic pressure from an assistant can help. The Gaskin Maneuver is mentioned on Wikipedia and via Google searches; the laboring mother is repositioned on all fours in order to create more space. I have not seen or heard of this maneuver in my EM textbooks or on the OB floors, but it makes great sense and should work--in a mother with no epidural! A Google search turns up anecdotal evidence, but this is no reason to disbelieve; midwives have been at their job a long time and much of OB is not evidence-based--try doing studies on pregnant women. Difficult.

Other initial options include the McRoberts maneuver, which is achieved by flexing and abducting both hips while laboring on the back. In practice, all deliveries were done in this position on the OB floor. If still stuck, the Woods Corkscrew maneuver is an option; reach in past the head with two fingers behind the stuck shoulder and rotate the baby about 180 degrees. Fingers go behind the shoulder to collapse the torso rather than open it up.

Truly horrible options then ensue. Keep in mind that by this time everyone is likely freaking out and the baby is probably quite literally dying in front of you. You can attempt to push the baby back into mom in order to go for a c-section--the so-called Zavanelli maneuver, which according to the namee was perfectly safe. This one is particularly funny since if you had such immediate access to any OB doc, you wouldn't be trying to push a large baby back into the uterus in the first place.

According to whonamedit.com, this maneuver was invented in the 70's by somebody named Gunn, and Zavanelli heard about it and told it to some other guy while he was volunteer teaching. So, if you want to use it, go ahead. Me, I'll put it in the same category as other things that should've stayed in the 70's, like the Pinto and Fleetwood Mac.

You can also deliver the posterior shoulder, by reaching up and grabbing the hand. Or, you can deliberately fracture the clavicle. Terrible sounding, but better than death. Actually, one of my deliveries had a fractured clavicle, and they heal well if there are no complications at the time.

The last option, a symphysiotomy, should scare everyone, not least because one of the tools needed is a finger guard. The pubic symphysis is the anterior joint of the pelvis and is just above the urethra and vagina. Apparently, in the late 1500's difficult deliveries were relieved with this method--using a scalpel to sever the ligament joining the two sides of the pelvis together anteriorally, allowing it to open so the baby can be delivered. I would have a hard time with this.

May we all have happy, quick but not too quick, ED deliveries, with no lacerations or post-partum hemorrhage.

Reichman and Simon, Emergency Medicine Procedures, McGraw-Hill

1 comment:

Anonymous said...

As a fellow ED intern rotating on OB nights, I can appreciate your FMOE posts... and the anxiety big babies can cause. In talking with an attending here, I learned the most important thing to have in the event of a shoulder dystocia:

"A seasoned nurse."