From the Editor

Tackle the challenging shoulder dystocia emergency by practicing delivery of the posterior arm

Author and Disclosure Information

 

References


Newborn injuries associated with shoulder dystocia

In a large retrospective study of 132,098 vaginal cephalic singleton births there were 2,018 cases of shoulder dystocia, representing a 1.5% rate of shoulder dystocia during vaginal birth.5A total of 101 neonatal injuries were reported in association with a shoulder dystocia, the most common being Erb’s palsy, clavicular fracture, and hypoxic ischemic encephalopathy. Some newborns incurred multiple injuries.
Type of injury No. of newborns with injury Rate of injury per 100 shoulder dystocias
Erb’s palsy
60
3
Clavicular fracture
39
1.9
Hypoxic ischemic encephalopathy
6
0.3
Klumpke’s palsy
4
0.2
Humerus fracture
2
0.1
Neonatal death
0
0

Source: Hoffman, et al. Obstet Gynecol. 2011;117(6):1272–1278.

Approaches to grasping the posterior arm
The posterior arm may be in one of three positions, and your approach to each position will be different.

Fetal hand near the chin. Delivery of the posterior arm is relatively easy when the fetal hand is in this position. Grasp the wrist gently and guide it out of the vagina. The fetal wrist should be pulled toward the fetal ear closest to the maternal symphysis.

Fetal hand on the abdomen. In this position, the operator can exert pressure on the antecubital fossa with the index and middle fingers, resulting in flexion of the forearm at the elbow. This will bring the fetal hand and wrist to the upper chest. The wrist then can be grasped and pronated over the fetal chest. The wrist and forearm are then pulled upward along the chest toward the fetal ear closest to the maternal symphysis.

Fetal upper extremity is extended with the hand next to the thigh. The most challenging situation is when the upper extremity of the fetus is extended along the trunk or behind the buttocks. In this situation the hand and wrist may be near the fetal thigh and very difficult to reach. In addition, the upper extremity may be tightly pinned between fetal trunk and maternal tissues, making it impossible to flex the forearm by gentle pressure on the antecubital fossa.

In this situation the operator’s hand must reach the fetal wrist and distal forearm, grasp these structures, and pull hard across the trunk to free the pinned upper extremity. The fetal wrist and distal forearm can be securely grasped using techniques pictured in the Figure. It can take 30 to 90 seconds for the operator to place a hand in the vagina, identify the posterior shoulder, follow the extended arm to the hand, and secure the wrist. Given the amount of time that it may take to accomplish the first steps of the maneuver, the nurse in the room should call out the time elapsed since the birth of the head at regular intervals to assist the obstetrician in pacing the speed of the intervention.

___________________________________________________________________________________________________

Figure. When the fetal upper extremity is extended and the hand is near the fetal thigh the fetal upper extremity may be tightly pinned between maternal and fetal tissues. Gentle pressure in the antecubital fossa may not cause the forearm to flex toward the vaginal introitus. In this situation it may be very difficult to grasp the fetal wrist or forearm. The operator should be prepared to place their entire hand and forearm into the vagina to reach the fetal wrist (Top left). Two options for grasping the fetal wrist are with the index finger and middle finger (Top right), or by encircling the wrist with the thumb and index finger (Bottom left). For many obstetricians, the index and middle fingers extend much further from their wrist than the thumb. Consequently, when the fetal wrist and hand are against the fetal thigh it may be easier to reach the fetal wrist with the operator’s index and middle finger. However, many obstetricians find that the thumb and index finger provide a more secure grip of the fetal wrist.

______________________________________________________________________________________________________

When the posterior arm is fully extended and pinned between fetal trunk and maternal tissues it can be very difficult to reach the fetal wrist. To help successfully complete the maneuver, the obstetrician should visualize placing his or her hand and entire forearm up to the elbow in the vagina to reach the fetal wrist. It may not be necessary to insert the entire forearm in the vagina, but the operator should visualize this step so he or she is prepared for the possibility.Surprisingly, the hollow of the sacrum often provides sufficient space for inserting the hand and entire forearm of the operator. In this process the operator’s hand and forearm may be strongly compressed by maternal and fetal tissues, cutting off circulation to the upper extremity. The operator’s upper extremity may quickly become numb, resulting in a reduction in tactile sensation and strength.

Next Article:

Women who were better informed chose fewer prenatal genetic tests

Related Articles