Naef R W, Martin J N
Division of Maternal-Fetal Medicine, Keesler Air Force Base, Jackson, Mississippi, USA.
Obstet Gynecol Clin North Am. 1995 Jun;22(2):247-59.
It is clear that in the vast majority of cases, shoulder dystocia cannot be predicted by the physician. Although macrosomia is strongly associated with shoulder dystocia in retrospective analyses, there are no clinical or sonographic parameters that can reliably and prospectively identify the individual macrosomic fetus. Furthermore, more than 98% of patients with macrosomic fetuses who deliver vaginally do not have shoulder dystocia. Some investigators have advocated the use of cesarean delivery for suspected macrosomic fetuses to avoid potential birth trauma during vaginal delivery; however, this strategy has not been shown to be beneficial in the majority of cases. Boyd and colleagues report that an increase in the cesarean delivery rate for suspected macrosomia from 8% in the 1960s to 21% in 1980 did not improve overall perinatal outcome among macrosomic infants. Since 50% to 90% of cases of shoulder dystocia occur in normally grown fetuses, cesarean delivery for all suspected macrosomic fetuses would not be expected to prevent the vast majority of cases of shoulder dystocia and would expose many mothers to a substantially increased risk for morbidity and mortality. Management of this complex problem requires clinical judgment by the well-trained physician and individualized care for each patient. Because shoulder dystocia remains unpredictable in almost all cases, when it does occur it must be managed expeditiously but carefully with one or more of the maneuvers described. The sequence of manipulations reported herein represents one way of managing shoulder dystocia (Fig. 11). As noted before, however, there are no data to support improved efficacy of one particular sequence over another. The sequence of maneuvers chosen by the clinician should be based on the algorithm with which he or she is most familiar and which has proven successful in their hands. Permanent injury to the fetus fortunately is rare but does occur even in the well-managed case.
显然,在绝大多数情况下,肩难产无法由医生预测。尽管回顾性分析显示巨大儿与肩难产密切相关,但没有临床或超声参数能够可靠且前瞻性地识别出单个巨大胎儿。此外,超过98%经阴道分娩的巨大胎儿患者并未发生肩难产。一些研究者主张对疑似巨大胎儿行剖宫产,以避免阴道分娩时潜在的产伤;然而,在大多数情况下,这一策略并未显示出有益效果。博伊德及其同事报告称,疑似巨大儿的剖宫产率从20世纪60年代的8%升至1980年的21%,但这并未改善巨大儿的总体围产期结局。由于50%至90%的肩难产病例发生在正常发育的胎儿中,因此对所有疑似巨大胎儿行剖宫产预计无法预防绝大多数肩难产病例,反而会使许多母亲面临发病率和死亡率大幅增加的风险。处理这一复杂问题需要训练有素的医生进行临床判断,并为每位患者提供个体化护理。由于几乎所有情况下肩难产都无法预测,因此一旦发生,必须迅速而谨慎地采用一种或多种所述手法进行处理。本文报道的操作顺序是处理肩难产的一种方法(图11)。然而,如前所述,没有数据支持一种特定顺序比另一种顺序具有更高的疗效。临床医生选择的操作顺序应基于其最熟悉且已在其手中证明成功的算法。幸运的是,胎儿永久性损伤很少见,但即使在处理得当的情况下也确实会发生。