Research. Shoulder dystocia is an uncommon

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1 Research OBSTETRICS Effects of shoulder dystocia training on the incidence of brachial plexus injury Steven R. Inglis, MD; Nikolaus Feier, MD; Jyothi B. Chetiyaar, MD; Margaret H. Naylor, CNM; Melanie Sumersille, CNM; Kelly L. Cervellione, MA; Mladen Predanic, MD OBJECTIVE: We sought to determine whether implementation of shoulder dystocia training reduces the incidence of obstetric brachial plexus injury (OBPI). STUDY DESIGN: After implementing training for maternity staff, the incidence of OBPI was compared between pretraining and posttraining periods using both univariate and multivariate analyses in deliveries complicated by shoulder dystocia. RESULTS: The overall incidence of OBPI in vaginal deliveries decreased from 0.40% pretraining to 0.14% posttraining (P.01). OBPI after shoulder dystocia dropped from 30% to 10.67% posttraining (P.01). Maternal body mass index (P.01) and neonatal weight (P.02) decreased and head-to-body delivery interval increased in the posttraining period (P.03). Only shoulder dystocia training remained associated with reduced OBPI (P.02) after logistic regression analysis. OBPI remained less in the posttraining period (P.01), even after excluding all neonates with birthweights 2 SD above the mean. CONCLUSION: Shoulder dystocia training was associated with a lower incidence of OBPI and the incidence of OBPI in births complicated by shoulder dystocia. Key words: Erb s palsy, obstetric brachial plexus injury, shoulder dystocia, shoulder dystocia training Cite this article as: Inglis SR, Feier N, Chetiyaar JB, et al. Effects of shoulder dystocia training on the incidence of brachial plexus injury. Am J Obstet Gynecol 2011;204:322.e1-6. Shoulder dystocia is an uncommon complication of childbirth that is often associated with adverse perinatal outcomes for both mother and baby, including obstetric brachial plexus injury (OBPI). Rates of shoulder dystocia have escalated over the past few decades, 1,2 which has intensified the importance of From the Department of Obstetrics and Gynecology (Drs Inglis, Feier, Chetiyaar, and Predanic), the Division of Nurse-Midwifery (Ms Naylor and Ms Sumersille), and the Department of Clinical Research (Ms Cervellione), Jamaica Hospital Medical Center, Jamaica, NY. Presented at the 31st Annual Meeting of the Society for Maternal-Fetal Medicine, San Francisco, CA, Feb. 7-12, The racing flag logo above indicates that this article was rushed to press for the benefit of the scientific community. Received Nov. 19, 2010; revised Jan. 7, 2011; accepted Jan. 18, Reprints: Steven R. Inglis, MD, Department of Obstetrics and Gynecology, Jamaica Hospital Medical Center, St., Suite 6A, Jamaica, NY singlis@jhmc.org /$ Mosby, Inc. All rights reserved. doi: /j.ajog understanding how to handle these emergencies and lessen the risk for infant morbidity. Even given this importance, there has been remarkably little progress toward developing a standardized, systematic approach for managing shoulder dystocia emergencies. Predicting shoulder dystocia in clinical practice has proven to be nearly impossible, 3 thus improved management is the only avenue for reducing risk of morbidity. Despite numerous efforts to ascertain which maneuvers most effectively resolve shoulder dystocia emergencies, 4,5 controversy remains about which are the most effective and safe approaches for managing these cases. 2,6-8 Although there are few clinical data to support their recommendations, shoulder dystocia training is now recommended by the Joint Commission on Accreditation of Healthcare Organizations in the United States 9 and mandated by the Clinical Negligence Scheme for Trusts in the United Kingdom 10 to reduce complications. Numerous studies have reported improved management of shoulder dystocia following training and practice using simulation models However, few have examined the incidence of serious complications in neonates from shoulder dystocia in clinical practice following such training. 15 Further, none have published a stepwise, detailed, and simple protocol to follow in cases of shoulder dystocia. The aim of the current study is to compare the rates of OBPI occurring in shoulder dystocia emergencies prior to and after the introduction of a simple shoulder dystocia protocol. By providing a standardized approach for all labor and delivery staff to follow during these emergencies, we hypothesized a significant reduction in the incidence of OBPI would result. MATERIALS AND METHODS A retrospective cohort study was conducted using information gathered from electronic medical records of mothers and their infants born from Aug. 1, 2003, through Dec. 31, The start date was selected as being the day on which our electronic medical records in labor and delivery began. Figure 1 summarizes the process of patient selection for the current study. Medical records of all patients with suspected shoulder dystocia and/or OBPI were identified by International 322.e1 American Journal of Obstetrics & Gynecology APRIL 2011

2 Obstetrics Research FIGURE 1 Flowchart of exclusion criteria of pretraining and posttraining periods All deliveries: n = 18,677 Pretraining: D: 9147 Posttraining: 9530 Deliveries in study groups n = 11,862 Pretraining: 6269; 52.67% Posttraining: 5593; 47.33% Excluded deliveries a n = 6815 Shoulder dystocia cases: 158 Pretraining: 83; 1.32% Posttraining: 75; 1.34% a Some deliveries are excluded for 1 reason. Pretraining: n = 2878; 31.46% Cesarean section: 2735; 29.90% Multiple births 83: 0.90% Vaginal breech: 6: 0.06% Non-live births: 118; 1.29% Posttraining: n = 3937; 41.44% Cesarean section: 3826;40.14% Multiple births: 106; 1.11%, Vaginal breech: 2; 0.02% Non-live births: 115: 1.20% Classification of Diseases, Ninth Revision, 6th edition code (660.4; 767.6; 767.7; 767.2). Shoulder dystocia was confirmed in all cases by review of the maternal intrapartum notes for evidence of shoulder dystocia (shoulder dystocia, tight/difficult shoulders, or turtle sign that required additional maneuvers to accomplish delivery) by an obstetrician (S.R.I., N.F., J.B.C.). Exclusion criteria included cesarean delivery, vaginal breech deliveries, multiple gestations, and/or non-live births. Some births were excluded for 1 of the above reasons. As per hospital protocol, all neonates with shoulder dystocia during birth are assessed by a neonatologist after delivery. Details of any neonatal injury (eg, decreased arm movement, suspected fracture) were recorded in the neonatal notes. Since shoulder dystocia management training was instituted during July and August 2006, all shoulder dystocia cases before July 1, 2006, were considered to be pretraining cases and all shoulder dystocia cases after Aug. 31, 2006, were considered to be posttraining cases (intent to treat). During the 2-month training period (July and August 2006), cases of shoulder dystocia in which standardized management was not activated (n 5) were included in the pretraining group; those in which standardized management was activated (n 2) were included in the posttraining group. The goal of implementing the shoulder dystocia training protocol was to simplify and standardize the management of shoulder dystocia emergencies. The training covered risk factors, early recognition, management, and documentation of shoulder dystocia. The training was conducted by maternal-fetal medicine specialists, the director of midwifery, and the clinical nurse manager of labor and delivery. The standardized shoulder dystocia training course was attended by all hospital labor and delivery staff (attending physicians, resident physicians, midwives, and nurses) and proficiency with the protocol was tested with a practical examination. Individual hands-on simulated shoulder dystocia training scenarios were mandatory and unsatisfactory proficiency warranted repeat training sessions and practical examination. All new staff were trained and certified upon hire; everyone underwent recertification in The practical training was performed on a prototype shoulder dystocia training mannequin (Obstetrical Manikin, part no ; Simulaids Inc, Woodstock, NY). The standardized shoulder dystocia training was designed to be a simple, systematic set of procedures. It is activated by the labor and delivery staff upon first recognizing the signs of shoulder dystocia. Once shoulder dystocia has been called, a hands-off procedure (no hands and no traction on the fetal head) is implemented. The operator first assesses the position of the anterior shoulder, announces this finding to the team, and begins to employ the maneuvers and/or position changes outlined in the protocol (Figure 2). Once the shoulder is oblique or the posterior arm has been delivered, maternal pushing is encouraged to complete the delivery. Quiet (conversational level) communication, a calm environment, and a deliberate response (no panic) to this emergency are emphasized. APRIL 2011 American Journal of Obstetrics & Gynecology 322.e2

3 Research Obstetrics FIGURE 2 Shoulder dystocia protocol d Shoulder Dystocia Cork Screw Maneuver Summon Aid a Hands off Procedure b Assess Shoulder Position Rotate to Oblique Suprapubic Pressure Deliver Posterior Arm Replace Head-CS Fracture Clavicle Symphysiotomy f Episiotomy e RESULTS Differences in characteristics of all deliveries between pretraining (n 6269) and posttraining (n 5593) study periods are outlined in Table 1. There was no difference in the incidence of shoulder dystocia (P.93) coupled with an overall decreased incidence of OBPI (P.01) during the study (Table 1). The proportion of infants born by cesarean delivery was higher in the posttraining period (P.05) (Figure 1). Among shoulder dystocia cases, there were no significant differences between Change Maternal Position c a Experienced obstetrician, nurse, anesthesiologist, neonatologist; b No fundal pressure, no pushing, no head traction; c McRobert, knee chest position, lateral position, squat; d Mandatory part of protocol; e Option or choice in protocol; f Proceed with cesarean delivery. pretraining and posttraining groups in terms of demographic characteristics, physical characteristics, or clinical profiles, with the exception of lower maternal body mass index (BMI) (P.01) and lower birthweight (P.02) in the posttraining group (Table 2). Even after removing all deliveries with a birthweight 2 SD above the mean from both groups, which rendered difference in birthweights insignificant (P.056), the incidence of Erb s palsy remained significantly less in the posttraining group (P.01). The parity (primipara and multipara) was compared between both groups and it did not differ significantly (P.05). The mean birthweight of the babies born by cesarean section in the pretraining period was g, almost equal to the mean birthweight of the babies born by cesarean section in the posttraining group ( g; P.42). The techniques used to manage shoulder dystocia emergencies changed considerably after implementation of the shoulder dystocia training (Table 3). There was a significant decrease in the use of McRobert maneuver (P.01) and increase in use of posterior arm delivery (P.02) and Rubin maneuver (P.003) in the posttraining group. While increased use of suprapubic pressure (P.05) is reaching statistical significance in the posttraining group. As hypothesized, patients with shoulder dystocia emergencies prior to implementation of training were 3.61 times more likely to develop OBPI than those delivered after implementation of training (relative risk, 0.277; confidence interval, ) (Figure 3). Maternal BMI, birthweight, and implementation of shoulder dystocia training were found to be independent predictors of reduced OBPI in our study. A binomial logistic regression was performed using all these factors as covariates to determine their confounding influence on the outcome. This analysis indicated only the association between shoulder dystocia training implementation and reduced incidence of OBPI identified in univariate testing remained significant (P.02) (Table 4). 322.e3 American Journal of Obstetrics & Gynecology APRIL 2011

4 Obstetrics Research TABLE 1 Characteristics of all deliveries during study period Characteristic Pretraining n 6269 a COMMENT In the current study, we examined the incidence of OBPI in cases of shoulder dystocia before and after implementation of a standardized shoulder dystocia training protocol. It should be noted since all OBPI cases were associated with shoulder dystocia and the shoulder dystocia rate did not change during the study, this suggests that greater recognition of shoulder dystocia posttraining was unlikely to be a confounding issue. The risk of OBPI before establishing standardized shoulder dystocia training was 3 times higher than the risk after establishing the training. Our findings support other findings comparing rates Posttraining n 5593 a P value b Shoulder dystocia 83 (1.32%) 75 (1.34%).93 OBPI 25 (0.40%) 8 (0.14%).01 Maternal age, y, mean NS c Maternal diabetes mellitus 239 (3.81%) 199 (3.56%).82 Spontaneous onset of labor 3124 (49.83%) 3765 (67.32%).00 Instrumental delivery 122 (1.95%) 157 (2.81%).11 Gestational age, d, mean NS OBPI, obstetric brachial plexus injury. a Presented as n (%) unless otherwise noted; b Determined by binomial test with pretraining proportion used as hypothesized proportion for posttraining period; c Not significant. TABLE 2 Characteristics of patients and deliveries in births complicated by shoulder dystocia Characteristic Pretraining (n 83) of neonatal injury before and after introduction of mandatory shoulder dystocia management training. 15 In that study, Draycott et al 15 found that the relative risk for developing OBPI was 4 times higher before introduction of training. Similarly, they found a decrease in fetal birthweight (P.02) in the posttraining group. Reported rates of OBPI (with or without shoulder dystocia) have varied tremendously due to definitional differences and diversity of samples. 8,15,16 Prior to shoulder dystocia training, our hospital experienced a rate of 3 cases of OBPI per 1000 live births (0.3%) and 4 cases per 1000 vaginal deliveries (0.4%); Posttraining (n 75) Significance (P) a Maternal age, y 26.9 (SD 5.96) 26.3 (SD 6.3).51 Maternal BMI 33.4 (SD 6.7) 30.3 (SD 5.1).01 Gestational age, d (SD 8.4) (SD 7.6).27 Birthweight, g (SD 510.4) (SD 439.8).02 Labor induction 28 (34%) 20 (26.67%).34 Labor augmentation 32 (39%) 31 (41.33%).72 Head-to-body delivery time, min 1.51 (SD 1.4) 2.00 (SD 1.2).03 Epidural 25 (30%) 19 (25.33%).50 BMI, body mass index. a Determined by Student t test or 2 test, as applicable. after training this rate was reduced to 1 per 1000 live births (0.1%) and 1 case per 1000 vaginal deliveries (0.1%). A recent review reports the incidence of OBPI between per 1000 live births ( %). 17 We believe the strength of this study is its standardized approach and simple protocol for management of all shoulder dystocia emergencies as a team effort. This simplified protocol allows for replication of this study in other samples. As well, the standardized approach facilitates study and comparison of shoulder dystocia maneuvers. This study is limited by the inherent variety of maneuvers and nearly limitless sequence of maneuvers that may be used during management of these emergencies. Draycott et al 15 noted a significant increase in the use of McRobert maneuver, suprapubic pressure, internal rotational maneuver, and delivery of posterior arm after management training. In the current study, however, there was a significant decrease (P.01) in the use of McRobert maneuver and increase in use of posterior arm delivery (P.02) and Rubin maneuver (P.03) in the posttraining group. Increased use of suprapubic pressure (P.05) is reaching statistical significance in posttraining group. Even given the differences between our study and that of Draycott et al 15 in terms of the maneuvers used, both found significant reductions in incidence of OBPI following initiation of the shoulder dystocia training. Since the prior studies of this kind did not use any multivariate analyses, it is impossible to determine whether their results were due to shoulder dystocia training, decreased maternal BMI, decreased birthweight, decreased parity, or other variables. In our study we used a multivariate technique to show that implementation of the shoulder dystocia training was related to the decrease in OBPI, not the decrease in the birthweight or maternal BMI. Even after removing all deliveries with a birthweight 2 SD above the mean from both the groups, which rendered difference in birthweights insignificant (P.056), the incidence of Erb s palsy remained signif- APRIL 2011 American Journal of Obstetrics & Gynecology 322.e4

5 Research Obstetrics TABLE 3 Incidence of use of shoulder dystocia maneuvers and obstetric brachial plexus injury in pretraining and posttraining groups Variable Pretraining Posttraining Relative risk (n 83) a (n 75) a (95% CI) FIGURE 3 Percent of obstetric brachial plexus injury in shoulder dystocia Significance (P value) McRoberts 56 (68%) 13 (17%) ( ).01 Suprapubic 54 (66%) 60 (80%) ( ).05 Woods corkscrew 36 (44%) 37 (49%) ( ).50 Rubin 14 (17%) 24 (32%) ( ).03 Posterior arm 37 (45%) 20 (26%) ( ).02 Instrumental 5 (6%) 8 (10%) ( ).29 Episiotomy 45 (54%) 40 (53%) ( ).91 OBPI 25 (30%) 8 (10%) ( ).01 CI, confidence interval; OBPI, obstetric brachial plexus injury. a 1 procedure/maneuver may have been used per delivery. TABLE 4 Results of binomial logistic regression predicting risk of obstetric brachial plexus injury Variable Unstandardized P value Shoulder dystocia training Birthweight Maternal BMI BMI, body mass index. icantly less in the posttraining group (P.01). A significant reduction in OBPI after implementation of a standardized shoulder dystocia training is of great clinical importance. This information can be utilized in the clinical setting to drastically reduce the risk of OBPI in shoulder dystocia emergencies, no matter how large the baby might be. In a 2008 shoulder dystocia simulation study, Crofts et al 18 reported that poor communication, inability to gain internal access, confusion over internal maneuvers, and the application of excessive traction were the difficulties most frequently noted during delivery. It is possible that the simple act of implementing shoulder dystocia training is helpful in reducing infant morbidity because it addresses each of these 4 points. Further research will need to be conducted to identify the most beneficial parts of the various protocols and training to maximize their effectiveness and utility for managing shoulder dystocia emergencies. At this point it is difficult to determine which part of our shoulder dystocia management training led to its apparent success in reducing the risk of OBPI. It is possible that teamwork alone led to a calm and relaxed environment that allowed all practitioners and patients to more effectively work together to relieve the obstruction. If nothing else, the hands-off procedure may simply have prevented traction on the fetal head during these emergencies. Lastly, prioritizing the assessment of the position of the shoulder, announcing this finding to the team, and attempting rotation to the oblique prior to attempting any other maneuvers may have made the difference. This study demonstrates that with a simple and standardized protocol in place, it is possible to improve the outcome of this dire emergency in obstetrics. Further studies are required to determine which part or parts of the protocol reduce morbidity for the neonate. The greatly improved neonatal outcome our hospital has experienced has brought renewed confidence to our staff that these unanticipated emergen- 322.e5 American Journal of Obstetrics & Gynecology APRIL 2011

6 Obstetrics Research cies can be successfully handled in the majority of cases. f REFERENCES 1. Dandolu V, Lawrence L, Gaughan JP, et al. Trends in the rate of shoulder dystocia over two decades. J Matern Fetal Neonatal Med 2005; 18: Mackenzie IZ, Shah M, Lean K, Dutton S, Newdick H, Tucker DE. Management of shoulder dystocia: trends in incidence and maternal and neonatal morbidity. Obstet Gynecol 2007; 110: Ouzounian JG, Gherman RB. shoulder dystocia: are historic risk factors reliable predictors? Am J Obstet Gynecol 2005;192: Allen RH. On the mechanical aspects of shoulder dystocia and birth injury. Clin Obstet Gynecol 2007;50: Gurewitsch ED, Kim EJ, Yang JH, Outland KE, McDonald MK, Allen RH. Comparing McRoberts and Rubin s maneuvers for initial management of shoulder dystocia: an evaluation. Am J Obstet Gynecol 2005;192: Gherman RB, Ouzounian JG, Goodwin TM. Obstetric maneuvers for shoulder dystocia and associated fetal morbidity. Am J Obstet Gynecol 1998;178: Gurewitsch ED. Optimizing shoulder dystocia management to prevent birth injury. Clin Obstet Gynecol 2007;50: Poggi SH, Allen RH, Patel CR, Ghidini A, Pezzullo JC, Spong CY. Randomized trial of McRoberts versus lithotomy positioning to decrease the force that is applied to the fetus during delivery. Am J Obstet Gynecol 2004; 191: Sentinel Event Alert Issue 30: preventing infant death and injury during delivery. Washington, DC: Joint Commission on Accreditation of Healthcare Organizations; July Clinical Negligence Scheme for Trusts, Maternity Clinical Risk Management Standards, version 1: National Health Service (UK), Litigation Authority; Jan. 2011: Crofts JF, Bartlett C, Ellis D, Hunt LP, Fox R, Draycott TJ. Management of shoulder dystocia: skill retention 6 and 12 months after training. Obstet Gynecol 2007;110: Crofts JF, Bartlett C, Ellis D, Hunt LP, Fox R, Draycott TJ. Training for shoulder dystocia: a trial of simulation using low-fidelity and highfidelity mannequins. Obstet Gynecol 2006; 108: Deering S, Poggi S, Macedonia C, Gherman R, Satin AJ. Improving resident competency in the management of shoulder dystocia with simulation training. Obstet Gynecol 2004; 103: Goffman D, Heo H, Pardanani S, Merkatz IR, Bernstein PS. Improving shoulder dystocia management among resident and attending physicians using simulations. Am J Obstet Gynecol 2008;199:294e Draycott TJ, Crofts JF, Ash JP, et al. Improving neonatal outcome through practical shoulder dystocia training. Obstet Gynecol 2008;112: Mehta SH, Blackwell SC, Hendler I, et al. Accuracy of estimated fetal weight in shoulder dystocia and neonatal birth injury. Am J Obstet Gynecol 2005;192: Zafeiriou DI, Psyhoogiou K. Obstetrical brachial plexus palsy. Pediatr Neurol 2008;38: Crofts JF, Fox R, Ellis D, Winter C, Hinshaw K, Draycott TJ. Observations from 450 shoulder dystocia simulations: lessons for skills training. Obstet Gynecol 2008;112: APRIL 2011 American Journal of Obstetrics & Gynecology 322.e6