Trauma During Pregnancy: Maternal Resuscitation, Rapid Response Team, and Protocols



Trauma During Pregnancy: Maternal Resuscitation, Rapid Response Team, and Protocols


Sally Radelat Raty

Kenneth L. Mattox

Uma Munnur

Andrew D. Miller

Mihaela Podovei



Introduction

Trauma during pregnancy is a significant contributor to both maternal and fetal morbidity and mortality in the United States. Motor vehicle accidents are the leading cause of injury-related maternal death, followed by violence and assault. Trauma is associated with first trimester pregnancy loss, premature labor, placental abruption, uterine rupture, and stillbirth (1). The ultimate goal is to provide the most advantageous care to both the mother and fetus, ordering diagnostic testing, and making therapeutic decisions with both patients in mind. As a rule, providing optimal care to the mother enhances fetal well-being and survival; however, when there is conflict between care that favors the mother’s survival and care that favors the survival of the fetus, the interests of the mother take priority.


Epidemiology

In the United States, an estimated 5% to 8% of women experience trauma during pregnancy. Trauma is the leading cause of non-obstetric death in the pregnant patient, and 20% of affected women require emergency surgery. The World Health Organization reports statistics on the top ten causes of death for women during their reproductive years according to country income (2). In low-income countries, HIV/AIDS (cause #1) and maternal conditions (cause #2) account for 41.8% of deaths within this age group. Trauma-related injuries including fires (#5), self-inflicted injuries (#6), and road traffic accidents (#8) are in the top ten causes of death for women during their reproductive years and in aggregate, account for 9.4% of deaths in this group. In middle-income countries, trauma-related injuries including road traffic accidents (#3), self-inflicted injuries (#4), and violence (#9) together account for 15.3% of deaths in this age group. In high-income countries, trauma-related injuries including road traffic accidents (#1), self-inflicted injuries (#2), and violence (#7) together account for 22.9% of deaths in this age group. Pregnancy itself does not worsen maternal survival; rather, maternal survival after trauma is related to the overall injury severity (3). The rate of trauma admissions rises with each trimester of pregnancy; 8% occur in the first trimester, 40% in second trimester, and 52% in the third trimester (4). Trauma is responsible for 0.3% to 0.4% of maternal hospital admissions (5). Although most pregnant trauma victims are eventually able to continue their pregnancies at home, as many as 38% remain hospitalized until delivery (4).

The major risk factors for maternal trauma include age less than 25 years, African American or Hispanic, use of alcohol or illicit drugs, domestic violence, improper seat belt use, and low socioeconomic status. Drugs and alcohol are factors in about 20% of maternal trauma (5). Education about the use of illicit drugs and alcohol during pregnancy in high-risk women may play a preventive role in maternal trauma. Proper seat belt use should also play a major role in preventing injuries. The American College of Obstetricians and Gynecologists (ACOG) and the National Highway Traffic Safety Administration recommend that women use a three point restraint system while in a motor vehicle, with the lap portion of the belt beneath the protuberant abdomen, snuggly across the highest portion of the thighs, and the shoulder strap worn to the side of the uterus, between the breasts and mid-clavicle (never directly across the protuberant abdomen) (6,7).


Maternal Injuries

Connolly and colleagues found that motor vehicle accidents are the most common injury in pregnant patients comprising 55%, followed by falls 22%, assaults 22%, and burns 1% (8) (Table 44-1). Younger pregnant patients are at a higher risk for trauma than older patients (9). Head injury and hemorrhagic shock are the major causes of maternal death following trauma.


Fetal Injuries

Motor vehicle accidents are the leading cause of fetal deaths related to maternal trauma comprising 82%, followed by firearm injuries 6%, and falls 3% (9). Maternal death accounted for 11% of fetal deaths (9). Fetal loss in the first trimester is not secondary to any direct uterine trauma but usually is due to maternal hypotension and hypoperfusion of the uterus (10). Providing optimal maternal care is the best strategy to optimize fetal survival. In early pregnancy, the only way to save the fetus is to save the mother (5).


Pre-Hospital Care

Pregnancy should be a consideration in any female trauma patient of reproductive age. If possible, a brief obstetric history should be obtained as part of the initial evaluation.

If the history reveals a gestational age above 18 to 20 weeks, left uterine displacement should be maintained in patients placed in the supine position. If no obstetric history can be elicited, but the patient has obvious signs of pregnancy, the gestational age is advanced enough to deserve pregnant patient considerations. The following table shows a correlation between the size of the uterus and the gestational age (Table 44-2).

If a trauma patient is pregnant, the guidelines for Advanced Trauma Life Support (ATLS) and pre-hospital care should be similar to those of the non-pregnant patient. Stabilizing the mother takes priority. In taking care of the mother, there are a few considerations specifically related to pregnancy:



  • Institute lateral decubitus or maintain left uterine displacement in supine position. If injury to the spine is
    suspected, the patient can be placed on a rigid board and the entire board tilted 30 degrees (11).








    Table 44-1 Causes of Maternal Trauma


















    Motor vehicle accidents
    Violence and assault
    Gunshots
    Stab wounds
    Strangulation
    Falls
    Suicide
    Burns



    • Rationale: Beginning at 18 to 20 weeks, the uterus causes aortocaval compression in supine position, decreasing the preload to the heart and potentially decreasing the cardiac output.


  • Start supplemental oxygen. Consider securing the airway early. In securing the airway, consider the need for early intubation against the higher probability of difficult airway.



    • Rationale: Oxygen consumption during pregnancy increases by 40% above non-pregnant levels. In addition, pregnant patients have decreased oxygen reserve (functional residual capacity [FRC] declines, tidal volume and minute ventilation increase, and closing capacity can be higher than the FRC). Weight gain, edema, engorgement of the airway mucosa, and increased mucosal friability, make airway instrumentation more likely to be difficult (12). Maternal hypoxia can cause fetal hypoxia and acidosis.


  • Secure intravenous access above the diaphragm with two large bore catheters.



    • Rationale: Aortocaval compression is responsible for a 30% decrease in cardiac output in the supine position during the third trimester. Caval compression decreases the venous return to the heart and increases the venous pressure in the lower extremities, with higher blood loss from pelvic or lower extremity trauma. Fluid resuscitation below the diaphragm may not be as effective as fluid administration above the diaphragm in improving cardiac output and supporting maternal hemodynamic stability.








      Table 44-2 Gestational Age and Uterine Location































      Gestational Age (wks) Location of the Top of the Uterus
      8 Just above pubis
      12 Halfway between pubis and umbilicus
      16 Two-thirds between pubis and umbilicus
      20 At umbilicus
      26 Just above umbilicus
      32 Halfway between umbilicus and xyphoid
      36 Three-fourths of the way between umbilicus and xyphoid
      40 Near xyphoid
      Adapted from: Mattox KL, Goetzl L. Trauma in pregnancy. Crit Care Med 2005;33:S385–S389.


  • Assess and treat hypotension. If transfusion is required and cross-matched or type-specific blood is not yet available, O-negative packed red blood cells (PRBCs) are a rational choice.



    • Rationale: During pregnancy, heart rate increases by only 10 to 15 beats/min and blood pressure drops by only 5 to 10 mm Hg. Any marked tachycardia or hypotension should not be considered to be normal physiologic changes of pregnancy. Lacking autoregulation, the uterus is very sensitive to changes in maternal blood pressure, and fetal well-being depends on adequate uterine blood flow.


  • If a chest tube is required, the insertion point should be one or two intercostal spaces higher than in the non-pregnant trauma patient (13).



    • Rationale: Beginning in the second trimester, the uterus becomes an abdominal organ, with upward displacement of the intra-abdominal contents and the diaphragm. The elevated position of the diaphragm requires adjustment of the chest tube insertion point to avoid abdominal injury during placement.


  • Consider the use of Military Anti-Shock Trousers (MAST)/pneumatic anti-shock garments for lower extremity trauma, but inflation of the abdominal portion is contraindicated (10).


  • Transport an injured third trimester patient to a trauma center as soon as possible even if the injuries lack apparent severity.



    • Rationale: Absence of abdominal tenderness or other “classic” abdominal signs in pregnancy does not exclude abdominal trauma. In a retrospective study of 203 trauma patients (victims of interpersonal violence), five out of eight fetal death cases occurred without apparent maternal injury (14). Fetal death with minor maternal injury was also documented in other series (15). Third trimester pregnancy at the time of traumatic injury is an independent risk factor for the need for specialized care in a trauma center (3,7,16).


Care in the Emergency Department (Ed)


Primary Survey

The emergency room primary survey for a trauma pregnant patient should be similar to the survey of a non-pregnant patient (17). While continuing the measures instituted for the pre-hospital care (left lateral displacement of the uterus, administration of supplemental O2, establishment of intravenous access), the primary survey should take 30 to 60 seconds and include assessment of the airway, breathing, circulation, and neurologic examination including a Glasgow coma score (7). If the cervical spine has been immobilized, inline stabilization should be maintained throughout the primary and secondary surveys. In addition to the differential diagnoses common to trauma patients, the pregnant trauma patient may have preeclampsia, eclampsia, placental abruption, or uterine rupture.


Secondary Survey

The secondary survey should include a comprehensive, head-to-toe inspection, palpation, and auscultation, with focus on the mechanism of injury, weapons used (if any), alcohol or drug involvement, and seat belt use. Obtaining a detailed past medical, surgical, and obstetric history is a priority with special attention paid to determination of the gestational age of the fetus. See Figure 44-1 flow diagram for clinical assessment of a pregnant trauma patient more than 20 weeks of gestation.







Figure 44-1 Clinical assessment of the pregnant trauma patient more than 20 weeks of gestation. aOld ecchymoses—suggestive of domestic abuse. bDetects maternal–fetal hemorrhage and allows calculation of immune globulin (RhoGAM, Ortho-Clinical Diagnostics, Inc., Rochester, NY) dosing in Rh-negative women (immune globulin 300 μg covers up to 15 mL of red cells bleed). Reprinted with permission from: Brown H. Trauma in pregnancy. Obstet Gynecol 2009;114(1):147–160.

As soon as the patient arrives in the ED, an obstetric consultation should be requested and fetal monitoring should be initiated. In addition to standard monitoring and resuscitation protocols, a vaginal examination, fetal heart rate monitoring and obstetric ultrasound are essential; vaginal bleeding is strongly associated with placental abruption and fetal loss (3). Placement of a urinary catheter provides a valuable monitor of both urine output and fluid resuscitative efforts and establishes the presence or absence of hematuria (18). Fetal heart tracing may give an earlier warning of impending maternal cardiovascular collapse than will maternal pulse and blood pressure alone. Thus, fetal monitoring is an important monitor of well-being for both mother and fetus. A normal fetal heart rate is 120 to 160 beats/min. Signs of fetal compromise include tachycardia, bradycardia, loss of variability, and recurrent decelerations.

In most series of blunt abdominal trauma during pregnancy, more than 70% of fetal losses result from abruptio placentae. The other less common causes of fetal loss are fetal–maternal hemorrhage and direct fetal injury (19). Considerable work has been done to establish screening tools and develop algorithms aimed at early detection of abruptio placentae. The presence of frequent uterine activity has been the most sensitive predictor of abruption. In one study, all patients that developed abruption had at least eight uterine contractions per hour during the initial 4-hour monitoring (20,21).

Continuous electronic fetal monitoring is the current standard of care following maternal trauma. Fetal monitoring should be initiated as soon as possible after maternal injury if the gestational age is >24 weeks (viable pregnancy). The duration of monitoring depends on the case scenario and institutional practice but in general, is maintained for at least 4 to 6 hours, and up to 24 hours for non-catastrophic trauma (22,23). Four-hour monitoring was advocated by Pearlman et al. who successfully identified all of the patients who developed abruption based on the uterine activity pattern recorded during the initial 4 hours of continuous monitoring. Pearlman advises continuing fetal monitoring past 4 hours in patients who have continued contractions (four or more per hour), rupture of amniotic membranes, vaginal bleeding, serious maternal injury, or fetal tachycardia, late decelerations, or non-reactive non-stress test (19,24). If fetal tachycardia or a non-stress test is non-reactive, monitoring is continued
for 24 hours (22). Some experts recommend 24-hour fetal monitoring for high-risk mechanisms of injury (i.e., ejections, lack of restraints, pedestrian collisions, assaults, Injury Severity Score (ISS) >9) (23). See Figure 44-2 for flow diagram of recommended observation protocol after maternal trauma.






Figure 44-2 Labor and delivery observation after maternal trauma. aDetects maternal–fetal hemorrhage and allows calculation of immune globulin (RhoGAM, Ortho-Clinical Diagnostics, Inc., Rochester, NY) dosing in Rh-negative women (immune globulin 300 μg covers up to 15 mL of red cells bleed). Reprinted with permission from: Brown H. Trauma in pregnancy. Obstet Gynecol 2009;114(1):147–160.

The ISS is an anatomical scoring system that provides an overall score for patients with multiple injuries. Six body regions (head, face, chest, abdomen, extremities, including pelvis, and external) are scored separately. Each injury is allocated to one of the six body regions and is assigned an Abbreviated Injury Score (AIS). The AIS can take a value of 0 (no injury) to 6 (non-survivable single organ injury) and is scored in terms of “threat to life.” Only the highest AIS score in each body region is used. The three most severely injured body regions have their score squared and added together to produce the ISS score (23).

The ISS score takes values from 0 to 75. If an injury is assigned an AIS of 6 (non-survivable injury), the ISS score is automatically assigned to 75. The ISS score is virtually the only anatomical scoring system in use and correlates linearly with mortality, morbidity, hospital stay, and other measures of severity (Table 44-3). Its weaknesses are that any error in AIS scoring increases the ISS error. Many different injury patterns can yield the same ISS score and injuries to different body regions are not weighted. Also, as a full description of patient injuries is not known prior to full investigation and operation, the ISS (along with other anatomical scoring systems) is not useful as a triage tool (25).








Table 44-3 ISS and Degree of Injury

















ISS Score Injury Grade
1–9 Minor injury
10–15 Moderate injury
16–24 Moderate/severe injury
≥25 Severe injury

Initial laboratory studies should include complete blood count (CBC), coagulation studies (prothrombin time [PT], activated partial thromboplastin time [PTT], International Normalization Ratio [INR], fibrinogen), electrolytes, and urinalysis. Arterial blood gasses (ABGs) including the measurement of serum bicarbonate or serum lactate may be indicated following significant trauma. The strong correlation between maternal trauma and substance misuse favor toxicology testing. Sending a sample of blood to the blood bank for type and cross-match with request for rapid determination of type, Rh status and antibody status is critically important. The Kleihauer–Betke (KB) test measures the amount of fetal hemoglobin transferred into the maternal circulation (fetal–maternal hemorrhage) and should be obtained on every injured pregnant patient (17,26). The KB test has particular utility in Rh-negative mothers but may be relevant in any pregnant patient. The test can be used to determine the need for Rh immune globulin and to identify the few patients for whom the quantity of immune globulin given is insufficient. A positive KB test may predict higher risk of preterm labor independent of the Rh status, and may indicate the need for longer fetal monitoring. One study showed an increased incidence of abruption in those with a positive test (26,27).


The Focused Abdominal Ultrasonography for Trauma (FAST) has an 80% to 85% sensitivity and a 98% to 100% specificity for free peritoneal fluid in pregnant patients. It is safe and rapid to perform and should be the first line diagnostic examination in abdominal trauma (7,17,26,28). In most cases, a computerized tomography (CT) scan will be used to further evaluate the pregnant patient following blunt trauma. Even so, a rapid fetal survey to assess the fetal heart rate, placental position, and abnormalities should be performed in any pregnant trauma patient (29). With the advent of bedside ultrasound and rapid CT scans, routine use of diagnostic peritoneal lavage (DPL) in the evaluation of traumatically injured patients has fallen out of favor. If performed during pregnancy, DPL should be performed using the supraumbilical approach in an open technique (26).

Other diagnostic studies including cervical spine, chest, abdomen, and pelvis images should be obtained for indications similar to those in the non-pregnant trauma patient. Radiation exposure to the fetus can be minimized by shielding the uterus whenever possible during imaging procedures (7). In 2010, the Eastern Association for the Surgery of Trauma (EAST) published their practice guidelines for the diagnosis and management of injury in the pregnant patient (30). Their recommendations are evidence-based, using a classification based upon level of evidence: Level I—randomized controlled trials (there were none); Level II—data collected prospectively and analyzed retrospectively i.e., cohort, observational, and case control studies; Level III—retrospective data collection and analysis, i.e., clinical series and reviews, and expert opinion. These are the guidelines (30):

Level I

There are no level I standards.

Level II



  • All pregnant women >20 weeks of gestation who suffer trauma should have cardiotocographic monitoring for a minimum of 6 hours. Monitoring should be continued and further evaluation should be carried out if uterine contractions, a non-reassuring fetal heart rate pattern, vaginal bleeding, significant uterine tenderness or irritability, serious maternal injury, or rupture of amniotic membranes is present.


  • KB analysis should be performed in all pregnant patients >12 weeks of gestation.

Level III

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Sep 16, 2016 | Posted by in ANESTHESIA | Comments Off on Trauma During Pregnancy: Maternal Resuscitation, Rapid Response Team, and Protocols

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