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Abstract

Shoulder dystocia is an uncommon but potentially catastrophic intrapartum event. Although risk factors such as maternal diabetes, obesity and macrosomia can be identified, shoulder dystocia most frequently occurs in patients who lack risk factors. Many maneuvers have been described to assist the operator in the safe release of the shoulder and subsequent delivery; however, no prospective trials have compared these maneuvers in such a way to suggest that one maneuver is superior to another. This article describes the identification of patients at risk for shoulder dystocia, clinical management of the shoulder dystocia, event documentation and the contemporary use of drills and simulation training to improve team preparedness for this unpredictable and usually unavoidable event.

Keywords

drills macrosomia obesity shoulder dystocia simulation training

What is shoulder dystocia?

Shoulder dystocia occurs when after the delivery of the fetal head, the shoulder fails to be delivered. The obstructed shoulder may be either the anterior or posterior shoulder; however, both shoulders may also be obstructed. The shoulders fail to be delivered when there is a discrepancy between the size of the fetal shoulders and the size of the pelvic inlet. The fetal shoulders either remain in an anterior–posterior position because of increased resistance between the fetus and the maternal pelvis or because of rapid expulsion and the failure of truncal rotation in the case of precipitous labor [1]. Although a turtle sign, represented by the retraction of the fetal head after expulsion, may herald shoulder dystocia, shoulder dystocia is not diagnosed until the usual attempts at the delivery of the head fail.

How common is shoulder dystocia & what are the complications?

This potentially catastrophic complication of delivery occurs at a frequency of 0.2–3% of all vaginal deliveries [1 –3]; however, this wide range is attributed to the lack of standard definitions for shoulder dystocia in the reported literature over time. When the standard definition, such as the interval between delivery of the head and body over 60 s, was applied, the incidence of shoulder dystocia was 10% and shoulder dystocia failed to be identified by the operator 25–45% of the time [4,5]. Although there has been a general rise in the percentage of fetuses weighing over 4000 g, Gherman reported, via analysis of 18 separate reports spanning 1980–1997, that the rate of shoulder dystocia has been stable over time [1]. Dandolu, however, reported a rise in shoulder dystocia over two decades among patients identified from the Maryland State database [6]. This increase may be associated with parallel increases in fetal birth weight and maternal obesity that have been observed over time [7,8]. Infants delivered after a shoulder dystocia is experienced, are at increased risk of birth injury (including but not limited to, brachial plexus injury, hypoxia and even death) [9]. Shoulder dystocia is also a leading cause of obstetrical litigation.

Macrosomia as a risk for shoulder dystocia

The greatest risk factors for shoulder dystocia continue to be maternal diabetes and fetal macrosomia [10]. Fetal macrosomia has been historically defined as birth weights over 4000 g, over 4500 g or over 5000 g. The American College of Obstetrics and Gynecology defines macrosomia as fetal weight of over 4500 g [11]. Studies report that the incidence of shoulder dystocia among macrosomic infants ranges from 4.2 to 22% in infants with a birth weight of greater than 5000 g [12–13]. Acker reported differences in rates of shoulder dystocia among nondiabetic women at a birth weight at over 4500 g. Those infants less than 4000 g had a shoulder dystocia rate of 1.1% whereas those infants weighing more than 4500 g, experienced shoulder dystocia 22 % of the time [14,15].

The relationship between increasing fetal weight, shoulder dystocia and brachial plexus injury is well established. In a cohort of macrosomic infants (>4500 g), the incidence of brachial plexus injury increased steadily from 0.8% in fetuses weighing 4500–4599 g to 2.86% in those weighing more than 5000 g. Maternal height may be another important factor, as brachial plexus injury increased from 2.1% in women taller than 180 cm to 35.1% in women shorter than 155 cm [10,16]. Data clearly support higher rates of shoulder dystocia and brachial plexus injury as fetal weight increases; however, it is important to note that although most shoulder dystocias occur in women with infants of normal weight [15], more permanent injury occurs among infants that are greater than 4500 g. This distribution of injury should be considered when managing a macrosomic infant.

Diabetes as a risk for shoulder dystocia & anthropomorphic considerations

Diabetes increases the risk for shoulder dystocia and in fact may augment the risks conferred by other factors [17]. Maternal diabetes is likely the most consistently reported risk factor for shoulder dystocia. The risk doubles across weight categories for infants of the diabetic mother. Risks of shoulder dystocia among diabetic women have been reported to be 12.2, 16.7, 27.3 and 34.8% for infants weighing 4000–4250, 4250–4500, 4500–4750 and 4750–5000 g, respectively [18]. As maternal diabetes is intimately associated with increases in macrosomia and since infants of diabetic mothers have alterations in fetal growth patterns when compared with infants of nondiabetic mothers, anthropomorphic prediction of shoulder dystocia has been evaluated. Cohen reported that in diabetic pregnancies, when the differences between the ultrasound measurements of the biparietal diameter minus the abdominal circumference exceeded 2.5 cm, shoulder dystocia was predicted 100% of the time [19]. Jazayeri reported that abdominal circumference was the best linear predictor of birth weight and that an abdominal circumference of 35 cm or more, predicted 93% of macrosomic infants [20]. While these findings are of interest, further evaluation of various imaging paradigms in large prospective cohorts will be necessary to conclude macrosomia can be reliably detected using anthropomorphic analysis.

Obesity as a risk for shoulder dystocia

The relationship between obesity and macrosomia is well recognized. Obesity is defined by the WHO and the NIH as a body mass index (BMI; wt[kg]/height [m²]) of 30 or greater [21]. Birth weights are reported to be larger in obese women. Weiss reported that the incidence of macrosomia, defined as a birth weight of over 4000 g, was 8.3% in a nonobese group, 13.3% in an obese group and 14.6% among morbidly obese women [22]. Although increases in shoulder dystocia have been reported in obese women [23], the relationship between obesity and shoulder dystocia may be largely related to the increase in macrosomia seen in this group, rather than to obesity alone. In support of this notion, Robinson reported no increase in shoulder dystocia among obese women with infants of normal weight [24]. Similar findings have been reported by other investigators who evaluated the relationship between pregnancy outcome and prepregnancy BMI. Usha Kiran et al. reported that in a population database of 60,167 deliveries, women with a BMI of over 30 had an increased risk for postdates, cesarean section, macrosomia, shoulder dystocia and failed instrumental delivery [23]. It is possible that an increase in cesarean section rates, particularly in obese women, has reduced the number of women who would have had shoulder dystocia in these analyses [25].

Recurrence risk of shoulder dystocia

Prospective randomized trials have not assessed the recurrence risk of shoulder dystocia. In small case studies, 6–16 shoulder dystocias per 100 attempted vaginal deliveries were noted; however, these studies were limited by the small study numbers and it is not clear whether mothers who had experienced one shoulder dystocia would have been more likely to deliver by cesarean section and thus avoid labor [26 –28]. In a larger case-controlled study using a state database, recurrent shoulder dystocia was seen in 11. 8% of women who had previous shoulder dystocia deliveries, and who had subsequent vaginal births [17]. Although overall recurrence rate may range from 1 to 16.7%, true incidence of recurrence risk is unknown since patients and providers may elect abdominal delivery when previous shoulder dystocia or birth injury has occurred [9]. It is reasonable to discuss and quote this risk range to a patient who has had a prior shoulder dystocia. Delivery plans can be made with appropriate risk awareness.

Ultrasound to predict macrosomia

Traditionally, fetal weight has been estimated by the clinical assessment of fundal height and by uterine palpation in the form of Leopold's maneuvers, which also assesses fetal presentation. Fetal weights can also be determined by ultrasound and can be predicted or estimated by the gravida. To reduce the neonatal risks of birth trauma, particularly the risks of shoulder dystocia, the clinician must attempt to identify babies who will weigh greater than 4500 g so delivery plans can be optimized to reduce risks. Widespread use of ultrasound has allowed for sonographic assessment of fetal weight; this assessment commonly supplements the clinical weight assessment. Several studies report that clinically estimated fetal weight can reliably predict fetal birth weight. Chauhan reported that in more than half of the models for ultrasound prediction of fetal weight, the clinical predictions by physicians were as accurate, or more accurate than sonography. This was especially true when the fetal weighs exceeded or were equal to 4000 g [29]. The margin of error of ultrasound fetal weight prediction appears to be similar to that observed when fetal weight is clinically estimated. Chauhan additionally reported that multiparous pregnant women themselves were as accurate as ultrasound or the physician in clinically estimating birth weights of their infants [30]. The patient's assessment or concerns about excessive fetal weight should not be ignored, particularly when a prior pregnancy has resulted in a difficult delivery or shoulder dystocia.

Among women without diabetes, ultrasound, when used to detect macrosomia, has a sensitivity of 22–44% and a predictive value of 30–44% in predicting fetal weight [11]. This wide range of sensitivity suggests that macrosomia cannot be reliably predicted or diagnosed. Data reporting serial sonographic assessment of fetal weight suggest that this technique may assist in identifying macrosomia. Biparietal diameter reported to be above two standard deviations on a growth curve and serially averaged abdominal circumferences that are over the 90th percentile using z scores, have reported sensitivities and specificities (100, 98, 84 and 100%) that are greater than those of estimated fetal weight alone [31]. Newer imaging techniques such as MRI or 3D ultrasounds may eventually contribute to the improvement of our ability to predict macrosomia via prospective trials. The relationships between maternal height, maternal weight and shoulder dystocia have been explored by several investigators. Among a cohort of 9967 women with vaginal deliveries, obesity and multiparity were the most significant risk factors for shoulder dystocia. Maternal height under 1.5 m and maternal height:infant weight ratios were also associated with shoulder dystocia. These investigators concluded that shoulder dystocia may be anticipated in deliveries involving short women and when a discrepancy occurs between maternal height or weight and infant weight [16]. The impact of maternal height on birth injury was additionally evaluated by Gudmundsson, who noted that the risk of birth injury is greatest when birth weight is higher and maternal height shorter [32].

Labor patterns associated with shoulder dystocia

Most literature supports the view that shoulder dystocia cannot be predicted by any labor pattern. Whereas labor arrest disorders and prolongation of the second stage of labor have been associated with shoulder dystocia in obese women, a consistent relationship between shoulder dystocia and labor pattern has not always been reported [14,33]. McFarland compared labor abnormalities between shoulder dystocia and nondystocia control groups and noted no differences in labor patterns. When diabetic and macrosomic infants (>4000 g) were analyzed separately and shoulder dystocia patients were compared with controls, the cohort still found no differences in labor abnormalities. A higher rate of prolonged second stage was seen among nulliparous women who had shoulder dystocia, suggesting that this may be an indicator for patients at risk [34]. Although other studies have evaluated labor patterns in relation to shoulder dystocia, inconsistent definitions of the length of the second stage of labor among investigators makes it difficult to draw a precise conclusion as to whether specific labor patterns predict risk [1]. A relationship between abnormal labor patterns and fetal weight has been established. An increase in the incidence of labor abnormalities in infants greater than 4500 g was reported by Acker. In this study, such labor abnormalities were not seen among average-weight infants [15]. Mehta et al. reported that the combination of fetal macrosomia (birth weight >4000 g), second stage of labor longer than 2 h and the use of operative vaginal delivery was associated with shoulder dystocia in nulliparous women [35]. Poggi, however, reported in a cohort of 80 matched patients that precipitous labor was the most common abnormality associated with shoulder dystocia [36]. No consistent later patterns of labor have been been described that will effectively predict shoulder dystocia.

Instrumental delivery & shoulder dystocia

Use of instrumental delivery is the only intrapartum risk factor that has been consistently associated with shoulder dystocia. In a case–control study of nondiabetic women with and without shoulder dystocia, Nuemann reported that women experiencing shoulder dystocia had significantly more labor augmentation and more instrumental deliveries [37].

Length of time for delivery

Although fetal death and hypoxic encephalopathy are the most severe outcomes related to shoulder dystocia, both are actually rare events. The Confidential Enquiry into Stillbirths and Deaths from Infancy reviewed 56 cases of fatal shoulder dystocia and reported that the head-to-body delivery interval was recorded as less than 5 min in 21 (47%) of cases and that only nine patients (21%) had a head-to-body delivery interval of greater than 10 min. Fetal compromise in labor was no more frequent in those babies who died following a short head-to-body delivery interval [2]. Using a dataset of litigated vaginal deliveries, Allen reported that head-to-body delivery intervals were significantly longer in neonates with 5 min Appearance, Pulse, Grimace, Activity, Respiration (APGAR) scores of less than 7 [38]. Since cord occlusion invariably occurs in shoulder dystocia births and since occlusion is rarely complete, it is difficult to establish a threshold of time wherein injury is certain to occur. Alternatively, it is clear that risks may increase as the time to complete delivery increases. This general assumption, however, has led to the erroneous conclusion that it is always imperative to immediately deliver the body after a shoulder dystocia has been identified. Iffy reports that a two-step delivery, wherein following the delivery of the head, the operator awaits for the next uterine contraction before attempting to deliver the shoulder, results in no untoward outcome [39].

Management of shoulder dystocia

Contemporary management of shoulder dystocia requires a calm operator and a well-thought-out plan of action. It is imperative that if not already present, help is summoned immediately after shoulder dystocia is recognized. This help may include additional nursing staff, an anesthesiologist, a pediatrician or neonatologist and an additional obstetrician or midwife. Future coordination may demonstrate that rapid response teams are best suited to attend to this emergency.

Once shoulder dystocia is identified, pushing should pause and the operator should prepare to implement maneuvers to relieve the dystocia. Appropriate positioning of the patient on the delivery table or bed with her buttocks at the end of the table is critical and will later allow for appropriate downward traction to facilitate delivery. The position of the fetal head should be noted, as this will need to be documented; knowledge of the head position will also allow for the appropriate application of suprapubic pressure.

Although many maneuvers have been described to alleviate shoulder dystocia, there are few prospective studies that have compared the various maneuvers. Retrospective studies have not demonstrated that any one maneuver is superior to the other at preventing birth injury.

McRoberts’ maneuver, which involves flexing the maternal thighs against the maternal abdomen, is commonly used as a first maneuver since it is easy to do. It is also sometimes performed prophylactically in an attempt to decrease the risk of shoulder dystocia or to shorten the second stage of labor. A randomized trial designed to assess whether prophylactic McRoberts’ maneuver and suprapubic pressure decreased the head-to-body interval in at-risk patients noted that the use of these combined maneuvers did not shorten the head-to-body delivery interval when compared with controls (24 ± 18 s vs 27 ± 20 s; p = 0.38) [40]. Gherman evaluated the success rate of McRoberts’ maneuver when used as the initial maneuver for shoulder dystocia and compared morbidity between those cases relieved by McRoberts’ maneuver and those that required additional maneuvers. In this cohort, the use of McRoberts’ maneuver was associated with a high degree of success in relieving the dystocia and decreased morbidity compared with other maneuvers [41]. Gonik has reported that this position reduces shoulder extraction forces, brachial plexus injury and clavicular fracture [42]; however, it should be noted that some patients, particularly those who are obese, may not be able to be placed in an effective McRoberts’ position [7].

Suprapubic pressure may be used as the first maneuver, or may be used in addition to McRoberts’ maneuver or in conjunction with rotational maneuvers. It is advised that this pressure be applied with the operator's hand placed directly above the symphysis pubis and directed either posteriorly or laterally, toward the fetal face. This posterior or lateral directional force allows for further abduction of the fetal anterior shoulder. The combination of McRoberts’ maneuver and suprapubic pressure has been reported to have a success rate of 58% [43]. Fundal pressure should be completely avoided as it may worsen the obstruction and can also be associated with uterine rupture [9].

Some shoulder dystocias will not be relieved with McRoberts’ maneuver and suprapubic pressure and rotational maneuvers will be required. Although obstruction of the bony pelvis will not be released by the performance of episiotomy, this step may best assist the operator in achieving room to perform rotational maneuvers or to deliver the posterior arm.

The Woods’ screw maneuver and the Rubin's maneuver are the most commonly described rotational maneuvers used to deliver the posterior arm. Woods originally advised that although the shoulders might be too large to be directly delivered through the maternal pelvis by pushing alone, using the model of a screw, he described a technique wherein by applying pressure to the anterior aspect (clavicular) of the posterior shoulder and abducting and rotating that shoulder, the posterior shoulder could be rotated 180° degrees to the anterior, and this would disimpact the obstructed anterior shoulder. The subsequent addition of gentle downward traction with a contraction would then result in delivery [44].

Rubin described a modification to the Woods’ maneuver that recommended that either the anterior or posterior shoulder, which ever was more accessible, be adducted and brought toward the fetal chest. In this maneuver the operator would place their hand on the posterior aspect (scapular) of the anterior or posterior shoulder and also rotate the baby 180° to reduce the obstruction. Rubin's original maneuver also included the concurrent application of lateral suprapubic pressure [45]. After the application of either rotational maneuver, delivery is attempted through the application of gentle downward traction in conjunction with maternal expulsive efforts.

Should a rotational maneuver fail, or in lieu of attempting a rotational maneuver first, an attempt may be made to deliver the posterior arm. It is not incorrect for this maneuver to be used first to reduce shoulder dystocia and this is advocated by some authors. Poggi describes a geometrical model wherein the delivery of the posterior shoulder results in reducing the obstruction by a factor of two, relative to the performance of McRobert's maneuver [46]. Baskett and Allen reported no neonatal injuries when posterior arm delivery was used as a primary method of delivery [47]. When shoulder dystocia is not responsive to the above measures, more extreme methods may be undertaken. Deliberate fracture of the clavicle will reduce the bisacromial diameter and facilitate delivery. Cephalic replacement, involving the replacement of the fetal head through the pelvis so abdominal delivery can occur, is a last resort effort and is associated with both maternal and fetal morbidity and mortality [48 –51].

A search for an improved understanding of shoulder dystocia-related injury has prompted the development of mechanical models to understand the forces that are generated during a delivery where a shoulder dystocia has occurred. Using a mathematical model, Gonik described that exogenous forces applied to the fetal neck are not the only forces operating on this area. In this model, uterine and maternal expulsive forces were noted to be four-times greater than the clinically applied forces [52]. Similar research on a mathematical model has demonstrated that the McRoberts’ position is associated with a reduction in the force applied to the fetal neck [53]. It is likely that the future development of models, and the ability to measure force in vivo, will provide more insight on shoulder dystocia and its optimal management.

Medical simulation is a relatively new field and is well suited to provide training in events that are rare, potentially catastrophic and that require coordinated teamwork. Shoulder dystocia is well suited for simulation training. Such training allows for trained individuals to recognize the problem and to effectively apply the maneuvers so that the fetal shoulder is disimpacted and the neonate is handed off to the pediatricians in a timely fashion [54]. Simulations have been used in the military and in airline injury as well as in other medical specialties to educate staff and to prepare teams for infrequently occurring catastrophes [55]. The obstetric birth simulator NOELLE (Gammard Scientific, FL, USA) is one such model. The effectiveness of the use of this model on improving resident competency in the management of shoulder dystocia was prospectively evaluated by comparing competency among a group of residents who received simulation training with a cohort where no training was received. Trained residents demonstrated higher scores in timelines and performance of maneuvers and completed delivery more quickly than the untrained cohort [56]. Using a novel birth simulator, designed by engineers at Johns Hopkins University in Baltimore, Maryland, USA, Rubin's maneuver was found to require the least amount of traction when compared with McRoberts’ maneuver for the initial management of shoulder dystocia [57]. Improvements not only in the use of maneuvers, but also in neonatal injury were seen when a retrospective review of management and outcomes before and after the introduction of a mandatory shoulder dystocia simulation training program was performed. In this study the rate of shoulder dystocia was not different between the two time periods; however, after training was introduced, there was more documented use of McRoberts’ position, suprapubic pressure, rotational maneuvers and delivery of the posterior arm. Although the injury rate was 2.04% before training and 2.00% post-training, a reduction in neonatal injury after training was noted [58]. Crofts evaluated the effectiveness of simulation by introducing a high-fidelity mannequin, which incorporates force perception training. Training using this method of force perception was compared with the use of a low-fidelity mannequin without force perception training. Training improved delivery rates, communication with patients, and use of maneuvers. Although peak applied force did not differ between the two groups, the total applied force was lower among those who had undergone force perception training [59]. Further studies using this model will demonstrate whether decreases in applied force are achieved after training.

Shoulder dystocia documentation is critical for both clinical and research purposes. If a precise sequence of events has been memorialized, this may allow for better understanding when an injury has occurred. Goffman used simulation training to evaluate whether documentation of the shoulder dystocia would improve post-training. Documentation and communication improved post-training but remained suboptimal and the authors concluded that the use of a standardized form may be the best way to obtain appropriate documentation [60]. Maslovitz additionally described the use of simulation-based hands-on training for obstetrical emergencies. This author reports that simulation allowed for detection of multiple management errors among teams, including inadequate documentation of the shoulder dystocia [61]. Osman similarly describes that one of the benefit of drills is to allow for identification of system problems [62]. Crofts evaluated skill retention post-shoulder dystocia training and found that most trainees retained these skills for 6 and 12 months [63]. The Joint Commission for Hospital Accreditation, which accredits and certifies more than 17,000 healthcare organizations in the USA, in its Sentinel Alert #30: Preventing Infant Death and Injury During Delivery, reviewed 40 cases of infant injury and seven cases of death and advised that organizations reduce risks of adverse events via various mechanisms including the use of team training, mock obstetrical emergency drills, shoulder dystocia drills and postevent debriefing to improve team performance [101].

Event documentation

After a shoulder dystocia occurs, it is critical that the event is appropriately documented in the medical record. The key components that should be documented on the chart are listed below:

Names of staff persons present at delivery and their roles

Risk factors for shoulder dystocia, if any

Estimated fetal weight and pelvimetry

Documentation of any labor abnormality

Type of anesthesia, if any

Timing of the delivery of the head

Timing of the delivery of the shoulders

Position of the fetal head at the time of delivery

Which shoulder was the anterior shoulder

Which maneuvers were used to achieve delivery and the order in which they were used

Whether episiotomy was performed and if lacerations were sustained

Whether maternal injuries were sustained

Whether fetal injuries were identified

The condition of the infant at birth

The results of umbilical cord gas analysis

Critical attention to detail is required when documenting a shoulder dystocia to ensure that key elements are not overlooked. Sample documentation forms exist in the literature and The Royal College of Obstetricians and Gynecologists has drafted a sample form [102].

Conclusion

Diabetes and macrosomia represent the greatest risk factors for shoulder dystocia; however, since most shoulder dystocias occur in normal-weight infants, shoulder dystocia is difficult to predict. Obesity and prior history of macrosomia and or shoulder dystocia represent additional risks. Sonographic diagnosis of macrosomia can be difficult and may not be superior to clinically assessed fetal weight. Although there are no labor patterns that predict brachial plexus injury, a precipitous second stage was the pattern most commonly associated with shoulder dystocia. The use of instrumental delivery in the face of a prolonged second stage of labor has additionally been shown to be associated with an increase in the rate of shoulder dystocia. The operator and delivering team should be familiar with the maneuvers used to manage shoulder dystocia and should have a concise plan to implement the maneuvers when this emergency occurs. The use of simulation training has been reported to improve operator awareness of the amount of force applied in simulated deliveries; however, no relationship to improvements in outcomes in live births have been identified. Retrospective studies demonstrate that simulation training improves the team's approach and that recall can persist up to 1 year post-training. Prospective studies will be needed to support further benefits of training. In addition long-term studies post-training will be necessary to determine whether simulation training reduces morbidity from shoulder dystocia. Detailed event documentation is an important part of the delivery process and will allow for appropriate analysis of events for medical, legal and research purposes.

Future perspective

Additional studies using force models may provide us with more information about how shoulder dystocia-related brachial plexus injuries occur. Improvements in diagnostic imaging may allow a more accurate prediction of fetal macrosomia. The obesity epidemic and the associated morbidity seen in pregnancy will spark further research into the role of specific maternal and fetal anthropomorphic measures in predicting shoulder dystocia. Additional studies using simulation models will not only focus on assisting in understanding of force, but may provide evidence of improvements in outcomes related to this intervention. The use of simulation drills will be prospectively evaluated and improvements in team preparedness for infrequent events may be further demonstrated. Trends in developing team readiness and the formulation of drills will coincide with national trends involving simulation in medical education. It will be common for obstetrical units to practice shoulder dystocia drills and drills will be required or encouraged by malpractice insurance carriers or hospital organizations. This will parallel a national trend in patient safety, which advocates the standardization of processes, but a direct improvement in shoulder dystocia-related injury may not be demonstrated.

Executive summary

Shoulder dystocia is an uncommon and usually unpredictable event.

Maternal diabetes, macrosomia, obesity and prior shoulder dystocia represent the largest categories of risk. Patients in these groups may be apprised of possible risks.

No specific labor pattern has been demonstrated to reliably predict shoulder dystocia.

The additional use of an instrument for delivery of a macrosomic infant is associated with an increase in the risk of shoulder dystocia.

When a shoulder dystocia risk exists, team preparedness should include a review of the maneuvers used to manage shoulder dystocia.

Although no one maneuver is superior to the other, ease of use frequently results in the use of McRoberts’ position and the application of suprapubic pressure as the first maneuvers. The operator should be familiar with the additional use of rotational maneuvers, the delivery of the posterior arm, use of episiotomy, clavicular fracture and cephalic replacement as management options.

Simulation training is an emerging science. Since shoulder dystocia is neither predictable nor preventable, the use of simulation training can improve team preparedness for this event and ensure that team members are aware of their individual roles in this emergency.

Appropriate event documentation is critical and can allow for appropriate understanding of the event when an injury occurs.

Footnotes

Dr Gittens-Williams does consultative work. This includes providing expert opinion and testimony about all aspects of high risk pregnancies. The author has no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

No writing assistance was utilized in the production of this manuscript.

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Contemporary Management of Shoulder Dystocia

Abstract

Keywords

What is shoulder dystocia?

How common is shoulder dystocia & what are the complications?

Macrosomia as a risk for shoulder dystocia

Diabetes as a risk for shoulder dystocia & anthropomorphic considerations

Obesity as a risk for shoulder dystocia

Recurrence risk of shoulder dystocia

Ultrasound to predict macrosomia

Labor patterns associated with shoulder dystocia

Instrumental delivery & shoulder dystocia

Length of time for delivery

Management of shoulder dystocia

Event documentation

Conclusion

Future perspective

Footnotes

References