Morrison J C, Sanders J R, Magann E F, Wiser W L
Department of Obstetrics and Gynecology, University of Mississippi Medical Center, Jackson.
Surg Gynecol Obstet. 1992 Dec;175(6):515-22.
Dystocia of the shoulder is an unpredictable obstetric emergency that may result in injury to the mother or fetus. In an effort to reduce such risks, attempts have been made to identify patients having a fetus who may subsequently develop shoulder dystocia. The literature, however, clearly reflects that even the combination of prenatal historic facts, estimated fetal weight and sequence of intrapartum events is ineffective in prospectively identifying infants whose births are complicated by shoulder dystocia. During a ten year period at the University of Mississippi Medical Center, the incidence of macrosomia, shoulder dystocia and subsequent brachial plexus injury was reviewed. The majority of instances (89 percent) of shoulder dystocia occurred in patients weighing less than 8 pounds 13 ounces at birth. In the current retrospective review, only 11 percent of the women had risk factors for macrosomia or shoulder dystocia and among these, none were identified prospectively. Additionally, 91 percent of patients with brachial plexus injury recovered with no sequelae. One instance of brachial plexus injury occurred at the time of cesarean section. These data reveal that macrosomia and subsequent shoulder dystocia cannot be predicted. Therefore, it is not feasible to prevent brachial plexus injury prospectively by prophylactic cesarean section. Great clinical acumen and technical expertise by the obstetrician using a variety of methods may be useful in avoiding, as much as possible, injury to the mother and fetus when shoulder dystocia does occur.
肩难产是一种不可预测的产科急症，可能导致母亲或胎儿受伤。为了降低此类风险，人们一直在努力识别那些胎儿可能随后发生肩难产的患者。然而，文献清楚地表明，即使将产前病史、估计胎儿体重和产时事件顺序结合起来，也无法前瞻性地识别出分娩时并发肩难产的婴儿。在密西西比大学医学中心的十年期间，对巨大儿、肩难产及随后臂丛神经损伤的发生率进行了回顾。大多数肩难产病例（89%）发生在出生体重低于8磅13盎司的患者中。在当前的回顾性研究中，只有11%的女性有巨大儿或肩难产的风险因素，而在这些患者中，没有一例是前瞻性识别出来的。此外，91%的臂丛神经损伤患者恢复后无后遗症。有一例臂丛神经损伤发生在剖宫产时。这些数据表明，巨大儿及随后的肩难产无法预测。因此，通过预防性剖宫产前瞻性地预防臂丛神经损伤是不可行的。当确实发生肩难产时，产科医生运用各种方法所具备的高超临床洞察力和技术专长，可能有助于尽可能避免对母亲和胎儿造成伤害。
