Emergent management of shoulder dystocia.
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.