Table of Contents

 

1. Abstract
2. Case Presentation
3. Introduction
4. Critical Appraisal Of The Literature
5. Epidemiology And Outcomes
6. Pathophysiology
   1. Cardiovascular
   2. Hematologic
   3. Pulmonary
   4. Gastrointestinal
   5. Musculoskeletal
7. Differential Diagnosis
8. Prehospital Care
9. Emergency Department Evaluation
   1. History
   2. Primary Survey
   3. Secondary Survey
10. Diagnostic Studies
    1. Laboratory Abnormalities
    2. Kleihauer-Betke Testing
    3. Fetal Cardiac Monitoring
    4. Imaging
       1. Ultrasound
       2. Magnetic Resonance Imaging
11. Treatment
12. Special Circumstances
    1. Carbon Monoxide And Cyanide Poisoning
    2. Isolated Orthopedic Injuries
    3. Domestic Violence
    4. Trauma Prevention (Seat Belts And Airbags)
    5. Amniotic Fluid Embolism
    6. Perimortem Cesarean Section
13. Controversies And Cutting Edge
14. Disposition
15. Summary
16. Risk Management Pitfalls For Pregnant Trauma Patients
17. Time- And Cost-Effective Strategies
18. Case Conclusions
19. Clinical Pathway For Management Of Pregnant Trauma Patients
20. Tables and Figures
    1. Table 1. Overview Of The Physiological Changes Of Pregnancy
    2. Table 2. Life- Threatening Diagnoses In Pregnant Trauma Patients
    3. Table 3. Estimated Conceptus Doses From Radiographic And Fluoroscopic Examinations
    4. Table 4. Estimated Conceptus Doses From Single Computed Tomographic Acquisition
    5. Figure 1. Fundal Height And Estimated Gestational Age
    6. Figure 2. Fetal Heart Rate Tracing Demonstrating Prolonged Deceleration
    7. Figure 3. Fetal Heart Rate Tracing Demonstrating Late Decelerations
    8. Figure 4. Fetal Heart Rate Tracing Demonstrating Variable Decelerations
    9. Figure 5. Third-Trimester Pregnancy Ultrasound
    10. Figure 6. Positive FAST Examination In Right Upper Quadrant
    11. Figure 7. Positive FAST Examination In Left Upper Quadrant
    12. Figure 8. The Correct Way To Wear A Seat Belt When Pregnant
    13. Figure 9. Perimortem Cesarean Section
21. References

Abstract

The management of acute trauma in the pregnant patient relies on a thorough understanding of the underlying physiology of pregnancy. This issue reviews the evidence regarding important considerations in pregnant trauma patients, including the primary and secondary survey as well as the possibility for Rh exposure, placental abruption, uterine rupture, and the need for a prompt perimortem cesarean section in the moribund patient. Because ionizing radiation is always a concern in pregnancy, the circumstances where testing provides benefits that outweigh risks to the fetus are discussed. Emergency clinicians are encouraged to advocate for trauma prevention, including proper safety restraints for motor vehicles and screening for domestic violence, as these measures have been shown to be effective in reducing morbidity and mortality in this population. Recommendations for monitoring, admission, discharge, and follow-up are also noted.

Key words: pregnancy, trauma in pregnancy, blunt trauma, motor vehicle collision, orthopedic injury, radiation in pregnancy, fetal monitoring, Rh immunization, perimortem cesarean section

Case Presentation

All shifts have a theme. Unfortunately, as you start your day in the ED, you realize that today’s theme is not your favorite. In the first hour of your shift, a 30-week pregnant patient arrives from a relatively minor motor vehicle collision. She was ambulatory at the scene despite presenting with lower extremity pain with an obviously deformed ankle and a sore neck. Otherwise, she looks fine, and she reassures you that she isn’t having any abdominal pain. She is insistent that she does not want any radiation, that she does not want to be observed, and that she would like to be discharged. Although rapid discharge seems attractive, you are concerned about the potential risk to the fetus and wonder what the best practice recommendations are for managing your 2 patients . . .

As you mull over how to best care for both this mother and baby, a second pregnant patient arrives. She is 24 weeks pregnant and fell while jogging. She thinks that she felt a contraction as the nurse was getting her into a gown. While well-appearing and embarrassed by her clumsiness, there is something about her that makes you feel uneasy . . .

Brooding that this just isn’t your day, the radio brings you back to reality as a very distraught paramedic hurriedly relates that they’re about 2 minutes out with another motor vehicle collision victim who looks sick and is tachycardic, hypotensive, and having agonal respirations. He relates that the husband is frantically screaming that she’s due next month to have a baby girl. As your team gears up for the ensuing disaster about to descend on your trauma room, you realize that the ambulance is going to arrive much faster than your obstetrician on call (who is coming from home). You fully appreciate that the opening moves of this drama are going to be entirely up to you. . . .

Introduction

Few things in emergency practice evoke more anxiety than the pregnant trauma patient. The “package deal” of 2 patients in 1 requires that the emergency clinician simultaneously manage both patients, only 1 of whom may be able to verbalize complaints. Pregnancy provokes anxiety in the patient (who often is concerned about possible complications to her unborn child due to trauma) as well as healthcare providers (who realize that intrauterine complications can be hidden). Careful attention to differences in maternal physiology during pregnancy and a broad differential of the possible complications of pregnancy (even with relatively minor trauma) are requisite to avoid catastrophe, as the physiology and nature of injuries can be strikingly different in a pregnant patient. In this issue of Emergency Medicine Practice, the approach to the pregnant trauma patient is reviewed; pitfalls of management are highlighted; and controversies in testing and imaging are discussed, including issues regarding radiation exposure for the fetus. An evidence-based approach to clinical decision making from the care of minor injuries to the perimortem cesarean section are presented.

Critical Appraisal Of The Literature

A literature search of current articles from 1946 to present was conducted with Ovid MEDLINE^® and PubMed utilizing the following search terms coupled with pregnant and pregnancy: trauma, blunt trauma, penetrating trauma, motor vehicle collision, orthopedic injury, fracture, perimortem cesarean section, trauma management, radiation, imaging, ultrasound, abruption, fetal monitoring, Kleihauer-Betke, Rh immunization, amniotic fluid embolism, uterine rupture, and carbon monoxide. The resulting 12,000 articles were limited to those published in the last 20 years, and they were evaluated for relevance and applicability. The remaining 162 articles were evaluated using standard evidence-level scales to determine their weight with regard to current practice. Bibliographies of relevant articles were then used to uncover further articles pertinent to the topic. The Cochrane Database of Systematic Reviews was searched using the terms pregnancy and trauma; the only relevant review concerned effective treatments for placental abruption. The Cochrane review authors concluded that there were no available data from which to draw any guidelines.¹

In assessing the body of literature as a whole, it is apparent that this is an area of emergency medicine that lacks definitive evidence and well-designed studies. Pregnant patients are often excluded from major protocols, and they represent a smaller subset of trauma patients that is frequently excluded from outcomes research. Consequently, the literature is rife with case studies and reports of small series of patients, but it is relatively scant on large prospective studies with regard to outcomes or specific interventions. A large body of case reports detail rare conditions that are difficult to effectively study. As a result, much of the evidence that exists must be interpreted in the light of expert opinion, considering the potential hazards while keeping in mind that such complications are relatively rare but cannot be missed.

Several sets of guidelines exist in the current literature; however, even these are primarily grounded in expert consensus and class III evidence, rather than well-designed studies. The American College of Obstetrics and Gynecology (ACOG) has published guidelines regarding the care of obstetric trauma patients that were last updated in 1998² (replacing Number 151, January 1991 and Number 161, November 1991). ACOG issued separate guidelines for administration of anti-Rh antibodies that specifically addressed trauma patients (last updated in 1999)³ and guidelines regarding appropriate diagnostic imaging (last updated in 2004).⁴ In September 2004, the American College of Emergency Physicians (ACEP) released guidelines on administration of Rh immune globulin to trauma patients in their first trimester as part of their first-trimester vaginal bleeding review,⁵ which mirrors ACOG guidelines. The Eastern Association for the Surgery of Trauma (EAST) has published guidelines regarding the surgical approach to trauma patients as recently as 2010.⁶ Likewise, Advanced Trauma Life Support^® (ATLS^®) general guidelines also exist for the surgical management of obstetric trauma. All of these guidelines were reviewed for this issue. To the authors’ knowledge, there is no current set of guidelines endorsed by any emergency medicine association that specifically addresses the resuscitation and care of the obstetric patient in the emergency department (ED).

Risk Management Pitfalls For Pregnant Trauma Patients

1. “She told me she wasn’t pregnant.” Incidental finding of pregnancy occurs, and it can happen to your trauma patient as well. Any female of reproductive age involved in trauma should have a screening pregnancy test sent as part of the initial workup.
2. "She wasn’t complaining of abdominal pain, so I wasn’t worried about the pregnancy.” Even relatively minor orthopedic injuries have been associated with adverse perinatal outcomes due to occult intrauterine trauma. All pregnant patients beyond 24 weeks—even those with relatively minor trauma—should have electronic fetal monitoring to assess for intrauterine pathology for a minimum of 4 to 6 hours.
3. “She didn’t look like she was that far along, so I wasn’t worried about the fetus.” Gestational age can be assessed by fundal height, bedside ultrasound, or prior medical records, but it should be assessed and the emergency clinician should err on the side of fetal viability, especially with regard to major resuscitations.
4. “I wasn’t worried about bleeding, so I didn’t order Rho(D) immune globulin.” Even minor trauma can result in fetal-maternal hemorrhage and complications in subsequent pregnancies in Rh-negative mothers. All pregnant patients with abdominal trauma or significant mechanism of injury should be Rh(D) typed and administered empiric Rho(D) immune globulin if they are Rh-negative.
5. "She looked fine, so I just discharged her home.” The abdominal examination and laboratory tests can be deceptive, even with minor trauma. All pregnant trauma patients should have a minimum of 4 to 6 hours of electronic fetal monitoring and obstetric follow-up prior to discharge from the ED.
6. “She was worried about radiation risks, so we didn’t do the imaging studies I would have normally done.”The relative risk of radiation for most routine ED x-rays and CT scans is well below the recommended threshold of radiation exposure during pregnancy and shouldn’t inhibit a thorough workup for trauma.
7. “I wanted to give the mother 1 round of CPR and check for fetal heart activity before doing a perimortem cesarean section.” The indication for perimortem cesarean section is loss of vital signs, and in order to have the baby out in less than 5 minutes, no delay should be undertaken before performing this potentially life-saving maneuver.
8. “I didn’t ask about domestic violence.” Domestic violence is more common during pregnancy and, frequently, a victim’s first contact with a medical provider is in the ED. Simple screening questions, asked in a private setting, can evaluate for further potential injuries.
9. “I figured she was wearing her seat belt.” The number 1 source of mortality for pregnant women is motor vehicle trauma. Education regarding proper lap and shoulder belt placement can prevent life threatening injuries.
10. “We just laid her down, and she suddenly lost her vital signs.” The supine hypotensive syndrome is common in later pregnancy and can result in syncope and dramatically reduced cardiac output. It is easily avoided by keeping the patient in the left lateral decubitus position or by tilting the spine board 15° to the left.

References

Evidence-based medicine requires a critical appraisal of the literature based upon study methodology and number of subjects. Not all references are equally robust. The findings of a large, prospective, randomized, and blinded trial should carry more weight than a case report.

To help the reader judge the strength of each reference, pertinent information about the study will be included in bold type following the reference, where available. In addition, the most informative references cited in this paper, as determined by the authors, are noted by an asterisk (*) next to the number of the reference.

1. Neilson J. Interventions for treating placental abruption. Cochrane Database of Syst Rev. 2003(1). Available at: http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD003247/abstract. Accessed December 2, 2012.
2. ACOG educational bulletin. Obstetric aspects of trauma management. Number 251, September 1998 (replaces Number 151, January 1991, and Number 161, November 1991). American College of Obstetricians and Gynecologists. Int J Gynaecol Obstet. 1999;64(1):87-94. (Committee guidelines)
3. ACOG practice bulletin. Prevention of Rh D alloimmunization. Number 4, May 1999 (replaces educational bulletin Number 147, October 1990). Clinical management guidelines for obstetrician-gynecologists. American College of Obstetrics and Gynecology. Int J Gynaecol Obstet. 1999;66(1):63-70. (Committee guidelines)
4. ACOG Committee Opinion. Number 299, September 2004 (replaces No. 158, September 1995). Guidelines for diagnostic imaging during pregnancy. Obstet Gynecol. 2004;104(3):647-651. (Committee guidelines)
5. Hahn SA, Lavonas EJ, Mace SE, et al. Clinical policy: critical issues in the initial evaluation and management of patients presenting to the emergency department in early pregnancy. Ann Emerg Med. 2012;60(3):381-390. (Clinical policy)
6. Barraco RD, Chiu WC, Clancy TV, et al. Practice management guidelines for the diagnosis and management of injury in the pregnant patient: the EAST Practice Management Guidelines Work Group. J Trauma. 2010;69(1):211-214. (Retrospective cohort study; 10,316 patients)
7. El-Kady D, Gilbert WM, Anderson J, et al. Trauma during pregnancy: an analysis of maternal and fetal outcomes in a large population. Am J Obstet Gynecol. 2004;190(6):1661-1668. (Retrospective cohort study; 10,316 patients)
8. Hyde LK, Cook LJ, Olson LM, et al. Effect of motor vehicle crashes on adverse fetal outcomes. Obstet Gynecol. 2003;102(2):279-286. (Retrospective cohort study; 322,704 patients)
9. Brown HL. Trauma in pregnancy. Obstet Gynecol. 2009;114(1):147-160. (Retrospective study; 1567 total patients, 102 pregnant)
10. Chames MC, Pearlman MD. Trauma during pregnancy: outcomes and clinical management. Clin Obstet Gynecol. 2008;51(2):398-408. (Review article)
11. Kuo C, Jamieson DJ, McPheeters ML, et al. Injury hospitalizations of pregnant women in the United States, 2002. Am J Obstet Gynecol. 2007;196(2):e161-e166. (Retrospective cohort study; 16,982 patients)
12. Bochicchio GV, Napolitano LM, Haan J, et al. Incidental pregnancy in trauma patients. J Am Coll Surg. 2001;192(5):566-569. (Retrospective study; 3976 total patients)
13. * Pearlman MD, Tintinallli JE, Lorenz RP. A prospective controlled study of outcome after trauma during pregnancy. Am J Obstet Gynecol. 1990;162(6):1502-1507. (Prospective cohort study; 86 pregnant patients)
14. Schiff MA, Holt VL. The injury severity score in pregnant trauma patients: predicting placental abruption and fetal death. J Trauma. 2002;53(5):946-949. (Retrospective study; 294 patients)
15. * Curet MJ, Schermer CR, Demarest GB, et al. Predictors of outcome in trauma during pregnancy: identification of patients who can be monitored for less than 6 hours. J Trauma. 2000;49(1):18-24. (Retrospective study; 271 patients)
16. Trivedi N, Ylagan M, Moore TR, et al. Predicting adverse outcomes following trauma in pregnancy. J Reprod Med. 2012;57(1-2):3-8. (Retrospective study; 292 patients)
17. Melamed N, Aviram A, Silver M, et al. Pregnancy course and outcome following blunt trauma. J Matern Fetal Neonatal Med. 2012;25(9):1612-1617. (Retrospective cohort study; 411 patients)
18. Petrone P, Talving P, Browder T, et al. Abdominal injuries in pregnancy: a 155-month study at two level 1 trauma centers. Injury. 2011;42(1):47-49. (Retrospective study; 321 pregnant patients)
19. Oyelese Y, Ananth CV. Placental abruption. Obstet Gynecol. 2006;108(4):1005-1016. (Review article)
20. Cahill AG, Bastek JA, Stamilio DM, et al. Minor trauma in pregnancy--is the evaluation unwarranted? Am J Obstet Gynecol. 2008;198(2):208 e201-e205. (Prospective cohort study; 317 patients)
21. El Kady D, Gilbert WM, Xing G, et al. Maternal and neonatal outcomes of assaults during pregnancy. Obstet Gynecol. 2005;105(2):357-363. (Retrospective population-based study; 2070 patients)
22. Weed BC, Borazjani A, Patnaik SS, et al. Stress state and strain rate dependence of the human placenta. Ann Biomed Eng. 2012;40(10):2255-2265. (Nonclinical study; 11 placentas)
23. Enakpene CA, Ayinde OA, Omigbodun AO. Incomplete uterine rupture, following blunt trauma to the abdomen: a case report. Niger J Clin Pract. 2005;8(1):60-62. (Case report)
24. Smith K, Deimling DL, Hinckley WR. Transporting the pregnant patient in shock: case report and review. Air Med J. 2009;28(1):37-39. (Case report)
25. Kramer MS, Rouleau J, Liu S, et al. Amniotic fluid embolism: incidence, risk factors, and impact on perinatal outcome. BJOG. 2012;119(7):874-879. (Retrospective population-based cohort study; 4,508,462 patients with 292 affected)
26. * Simpson KR, James DC. Efficacy of intrauterine resuscitation techniques in improving fetal oxygen status during labor. Obstet Gynecol. 2005;105(6):1362-1368. (Randomized study; 42/51/49 patients in each arm)
27. * Jeejeebhoy FM, Zelop CM, Windrim R, et al. Management of cardiac arrest in pregnancy: a systematic review. Resuscitation. 2011;82(7):801-809. (Meta-review article)
28. Fromm C, Likourezos A, Haines L, et al. Substituting whole blood for urine in a bedside pregnancy test. J Emerg Med. 2012;43(3):478-482.
29. Abouleish EI, Abboud TK, Bikhazi G, et al. Rapacuronium for modified rapid sequence induction in elective caesarean section: neuromuscular blocking effects and safety compared with succinylcholine, and placental transfer. Br J Anaesth. 1999;83(6):862-867. (Randomized blinded trial; 42 patients)
30. Muench MV, Baschat AA, Reddy UM, et al. Kleihauer-Betke testing is important in all cases of maternal trauma. J Trauma. 2004;57(5):1094-1098. (Retrospective study; 166 pregnant patients)
31. Salim R, Ben-Shlomo I, Nachum Z, et al. The incidence of large fetomaternal hemorrhage and the Kleihauer-Betke test. Obstet Gynecol. 2005;105(5 Pt 1):1039-1044. (Prospective cohort study; 313 cases and 253 controls)
32. * Stout MJ, Cahill AG. Electronic fetal monitoring: past, present, and future. Clin Perinatol. 2011;38(1):127-142. (Review article)
33. Richards JR, Ormsby EL, Romo MV, et al. Blunt abdominal injury in the pregnant patient: detection with US. Radiology. 2004;233(2):463-470. (Retrospective study; 2319 total patients, 328 pregnant)
34. Goodwin H, Holmes JF, Wisner DH. Abdominal ultrasound examination in pregnant blunt trauma patients. J Trauma. 2001;50(4):689-693. (Retrospective study; 127 patients)
35. Brown MA, Sirlin CB, Farahmand N, et al. Screening sonography in pregnant patients with blunt abdominal trauma. J Ultrasound Med. 2005;24(2):175-181. (Retrospective study; 1567 total patients, 102 pregnant)
36. Kopelman TR, Berardoni NE, Manriquez M, et al. The ability of computed tomography to diagnose placental abruption in the trauma patient. J Trauma Acute Care Surg. 2013;74(1):236-241. (Retrospective review; 176 patients)
37. * Wang PI, Chong ST, Kielar AZ, et al. Imaging of pregnant and lactating patients: part 1, evidence-based review and recommendations. AJR Am J Roentgenol. 2012;198(4):778-784. (Committee guidelines)
38. Roderique EJ, Gebre-Giorgis AA, Stewart DH, et al. Smoke inhalation injury in a pregnant patient: a literature review of the evidence and current best practices in the setting of a classic case. J Burn Care Res. 2012;33(5):624-633. (Review article)
39. Wolf SJ, Lavonas EJ, Sloan EP, et al. Clinical policy: critical issues in the management of adult patients presenting to the emergency department with acute carbon monoxide poisoning. Ann Emerg Med. 2008;51(2):138-152. (Committee guidelines)
40. Elkharrat D, Raphael JC, Korach JM, et al. Acute carbon monoxide intoxication and hyperbaric oxygen in pregnancy. Intensive Care Med. 1991;17(5):289-292. (Prospective study; 44 patients)
41. El Kady D, Gilbert WM, Xing G, et al. Association of maternal fractures with adverse perinatal outcomes. Am J Obstet Gynecol. 2006;195(3):711-716. (Retrospective cohort study; 3292 patients)
42. Cannada LK, Pan P, Casey BM, et al. Pregnancy outcomes after orthopedic trauma. J Trauma. 2010;69(3):694-698, (Observational study; 1055 total patients, 65 pregnant patients)
43. Greenberg EM, McFarlane J, Watson MG. Vaginal bleeding and abuse: assessing pregnant women in the emergency department. MCN Am J Matern Child Nurs. 1997;22(4):182-186. (Cross-sectional survey; 261 patients)
44. Leone JM, Lane SD, Koumans EH, et al. Effects of intimate partner violence on pregnancy trauma and placental abruption. J Womens Health (Larchmt). 2010;19(8):1501-1509. (Retrospective study; 2873 patients)
45. McFarlane J, Parker B, Soeken K, et al. Assessing for abuse during pregnancy. Severity and frequency of injuries and associated entry into prenatal care. JAMA. 1992;267(23):3176-3178. (Prospective cohort study; 691 patients)
46. Sirin H, Weiss HB, Sauber-Schatz EK, et al. Seat belt use, counseling and motor-vehicle injury during pregnancy: results from a multi-state population-based survey. Matern Child Health J. 2007;11(5):505-510. (Cross-sectional study; 37,081 patients)
47. Klinich KD, Schneider LW, Moore JL, et al. Investigations of crashes involving pregnant occupants. Annu Proc Assoc Adv Automot Med. 2000;44:37-55. (Case series; 16 patients)
48. Klinich KD, Flannagan CA, Rupp JD, et al. Fetal outcome in motor-vehicle crashes: effects of crash characteristics and maternal restraint. Am J Obstet Gynecol. 2008;198(4):450 e451-e459. (Retrospective; 57 patients)
49. Bard MR, Shaikh S, Pestaner J, et al. Direct fetal injury due to airbag deployment and three-point restraint. J Trauma. 2009;67(4):E98-E101. (Case report)
50. Metz TD, Abbott JT. Uterine trauma in pregnancy after motor vehicle crashes with airbag deployment: a 30-case series. J Trauma. 2006;61(3):658-661. (Case series; 30 patients)
51. Schiff MA, Mack CD, Kaufman RP, et al. The effect of air bags on pregnancy outcomes in Washington state: 2002-2005. Obstet Gynecol. 2010;115(1):85-92. (Retrospective cohort study; 3348 patients)
52. Ellingsen CL, Eggebo TM, Lexow K. Amniotic fluid embolism after blunt abdominal trauma. Resuscitation. 2007;75(1):180-183. (Case report)
53. Conde-Agudelo A, Romero R. Amniotic fluid embolism: an evidence-based review. Am J Obstet Gynecol. 2009;201(5):445 e441-e413.
54. Dijkman A, Huisman CM, Smit M, et al. Cardiac arrest in pregnancy: increasing use of perimortem caesarean section due to emergency skills training? BJOG. 2010;117(3):282-287. (Retrospective cohort study; 55 patients)
55. * Katz V, Balderston K, DeFreest M. Perimortem cesarean delivery: were our assumptions correct? Am J Obstet Gynecol. 2005;192(6):1916-1920. (Literature review article; 38 cumulative cases)
56. Katz VL. Perimortem cesarean delivery: its role in maternal mortality. Semin Perinatol. 2012;36(1):68-72. (Clinical policy)

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