Nocon J J, McKenzie D K, Thomas L J, Hansell R S
Department of Obstetrics and Gynecology, Indiana University School of Medicine, Indianapolis.
Am J Obstet Gynecol. 1993 Jun;168(6 Pt 1):1732-7; discussion 1737-9. doi: 10.1016/0002-9378(93)90684-b.
The purpose of this study was to determine whether there is a risk profile for predicting or preventing shoulder dystocia and whether any of the obstetric maneuvers to disimpact a shoulder reduce the likelihood of permanent injury.
A retrospective analysis of 14,297 parturients with 12,532 vaginal deliveries and 1765 cesarean sections (12.4%) from January 1986 through June 1990 was performed. A total of 204 maternal and infant charts, related to shoulder dystocia or neonatal injury, were reviewed in depth for age, parity, episiotomy, type of delivery, hemorrhage, maternal obesity, diabetes, weight gain, fetal weight, sex, and Apgar scores. In addition, the type of maneuver or combination thereof used to relieve the dystocia, type of injury to the infant, and follow-up of the injury were reviewed.
The 185 coded episodes of shoulder dystocia represent 1.4% of all vaginal deliveries (12,532). There were 42 injuries recorded: 14 fractured clavicles and 28 brachial plexus injuries. An additional 19 patients, not coded for shoulder dystocia, sustained 14 fractured clavicles and five brachial plexus injuries. All but one of the brachial plexus injuries resolved by 6 months. The occurrence of shoulder dystocia increased in direct relationship to the birth weight and becomes significant in newborns over 4000 gm (p < 0.01). The occurrence of a previous large infant was also a significant risk factor (p < 0.01). Diabetes and midforceps delivery become significant factors only in the presence of a large fetus. Obesity, multiparity, postdate pregnancy, use of oxytocin, low forceps delivery, episiotomy, and type of anesthesia were unrelated to shoulder dystocia. No delivery method was without injury.
This study clearly indicates that most of the traditional risk factors for shoulder dystocia have no predictive value, shoulder dystocia itself is an unpredictable event, and infants at risk for permanent injury are virtually impossible to predict. In addition, no delivery method in shoulder dystocia was superior to another with respect to injury. Thus no protocol should serve to substitute for clinical judgment.
本研究旨在确定是否存在用于预测或预防肩难产的风险特征，以及任何解除胎肩嵌塞的产科操作是否能降低永久性损伤的可能性。
对1986年1月至1990年6月期间的14297例产妇进行回顾性分析，其中有12532例阴道分娩和1765例剖宫产（12.4%）。对总共204份与肩难产或新生儿损伤相关的母婴病历进行了深入审查，内容包括年龄、产次、会阴切开术、分娩方式、出血情况、产妇肥胖、糖尿病、体重增加、胎儿体重、性别和阿氏评分。此外，还审查了用于缓解难产的操作类型或其组合、婴儿的损伤类型以及损伤的随访情况。
185例编码的肩难产事件占所有阴道分娩（12532例）的1.4%。记录到42例损伤：14例锁骨骨折和28例臂丛神经损伤。另外19例未编码为肩难产的患者发生了14例锁骨骨折和5例臂丛神经损伤。除1例臂丛神经损伤外，其余所有损伤在6个月内均痊愈。肩难产的发生率与出生体重直接相关，在出生体重超过4000克的新生儿中显著增加（p<0.01）。既往有巨大儿出生也是一个显著的风险因素（p<0.01）。糖尿病和中位产钳助产仅在存在巨大胎儿时才成为显著因素。肥胖、多产、过期妊娠、使用缩宫素、低位产钳助产、会阴切开术和麻醉类型与肩难产无关。没有一种分娩方式是无损伤的。
本研究清楚地表明，大多数传统的肩难产风险因素没有预测价值，肩难产本身是一个不可预测的事件，几乎不可能预测有永久性损伤风险的婴儿。此外，在肩难产中，没有一种分娩方式在损伤方面优于另一种。因此，任何方案都不应替代临床判断。
