SHOULDER DYSTOCIA: DIAGNOSIS, MANAGEMENT AND RISK PREVENTION
Nothing can reduce a grown man to tears faster than a shoulder dystocia! Shoulder entrapment during delivery is a true obstetric emergency that can result in significant material and infant trauma. The maternal and fetal consequences of shoulder dystocia can be devastating. Infant complication occurs in up to 20 percent of cases and includes traumatic brachial plexus injury, humeral fracture and clavicular fracture. The incidence of severe birth asphyxia and related complication is 143 per 1,000 births for delivery with SD as compared with 14 per 1,000 births for all deliveries.
I. Diagnosis: usually made only after the head has been delivered. Certain signs then appear:
1. Definite recoil of the head back against the perineum (turtle sign).
2. Because of the friction with the vulva, the head seems incapable of movement
3. The problem is usually recognized when traction from below and pressure from above fail to deliver the newborn
4. Vaginal examination is made to rule out other cause of difficulty, such as:
i. Short umbilical cord
ii. Abdominal or thoracic enlargement of the infant (malformations, neoplasm)
iii. Locked or conjoined twins
iv. Uterine constriction ring
When excessive force and lateral extension of the neck are applied during deliveries, brachial plexus injury occurs. Erb's palsy, commonly associated with shoulder dystocia, results from injury to the fifth and sixth cervical nerve roots. Some recognized risk factors for this brachial plexus palsy are fetal Macrosomia (large fetus weighing 4500-5000 grams or near 10 lbs), abnormal labor (protraction disorders, prolonged second stage), midpelvic operative delivery, maternal obesity and maternal diabetes, as identified above. Although nearly 80% of Erb's palsies will resolved by 3-6 months of age, 1% to 5% persist one year after delivery with paralysis of the upper arm muscles and winging of the scapula.
The fact that the neurological and neonatal literature has not changed, recent obstetrical literature has been written in an attempt to help health care providers defend these cases. Over the past few years, some obstetrical researchers have published reports hypothesizing that brachial plexus injures are unpredictable and result from forces within the uterus itself. Articles by Sandmire and DeMot, Gonik, Waler and Grimm argue that it the propulsive action of the uterus stretching the nerves of the brachial plexus that cause brachial palsy injuries. They draw their conclusion from the works of other research who reviewed the records of infant who were born with brachial plexus injures and whose obstetrician or birth attendant did not document should dystocia at the time of birth. In a different retrospective review of 26,033 vaginal births in which brachial plexus injury occurs, Gonik, Hollyer and Allen concluded that shoulder dystocia was underreported because the diagnosis relies on retrospective and subjective information processed by the clinician. The better explanation is that when the anterior arm was involved in the SD, the posterior arm was forcefully maneuvered in the delivery because the anterior arm could not be reached, thereby resulting in injury to the posterior arm.
- It is likely that excessive traction was applied before or during the McRoberts (legs lifted up over abdomen by nurses or father) maneuver and remained unrecorded.
- Details of a delivery are recorded after the delivery is over and the outcome is known.
- Many OBs believe they can hide their negligence and better defend themselves by simply leaving the facts out of the records or "doctoring" the records by not recording shoulder dystocia had occurred.
- Parents, other observers and depositions or videotaped delivery recordings indicate that the SD was not recorded in the medical chart.
- When increased difficulty is encountered with deliveries, Obstetricians often apply increasing or fast or forceful amounts of lateral traction to the fetal head.
- Researchers should not conclude that brachial plexus injuries occur without SD and/or without lateral extension of the fetal head.
- Excessive force can be applied with the assistance of forceps and vacuum extractors regardless of the presentation.
- Gonik's article based on a mathematical model is flawed and they likened their model of the fetus and uterus to the hard surface of a piston. They readily admit that the model does not account for the soft tissue resistances, the dissipation of forces and pressures related to the shoulder dystocia event. The body form diagram in Gonik's articles is incorrect from an engineering standpoint since it is not in equilibrium as the sum of all forces does not add up to 0.
- Shoulder dystocia malpractice cases cannot be properly defended based on recent non-scientific subjective articles written by biased obstetrician who have their own self-interest foremost in their writing.
- The worse the injury to the child, the more likely the injury aw in fact caused by excessive force on the part of the obstetrician or delivery attendant. For instance, where a child's nerves are found to be totally avulsed in a subsequent surgery for repair, it is certain such injury was due to obstetrical negligence because there are no reported cases or even any theoretical articles in the medical literature that suggest or relate that such a devastating injury is due to the natural forces of labor. There is no scientifically demonstrated way that the natural forces of labor or a proper delivery can result in total avulsion of an infant's nerves.
Read Doctor Sugarman's Recent Shoulder Dystocia Award