Pregnancy

Key Practice Points

  • All women of child-bearing age are pregnant until proven otherwise
  • The best outcome of the fetus is dependent upon optimal management of the mother
  • Even minor trauma can result in uterine rupture, fetal-maternal hemorrhage, placental abruption, pre-term labor and fetal loss
  • Pregnant trauma patients should be assessed and managed using a standard ABCD approach whilst recognizing the anatomical and physiological changes that occur in pregnancy
  • The management of a severely injured pregnant patient is best undertaken by a multi-disciplinary team with early involvement of obstetric clinicians

 

The goals of treatment are to maintain adequate feto-uterine perfusion and oxygenation by precenting hypoxia, hypotension, acidosis and hypothermia

 

Primary Survey

As for non-pregnant patients, the priority for pregnant women following trauma remains the identification of imminent life threats affecting the airway, breathing and circulation

 

Maintain awareness of pregnancy-related anatomical and physiological change that may mask signs of early deterioration and/or complicate management

 

Airway 

The pregnant patient has a greater risk for airway management problems and difficult intubation comparted to the non-pregnant patient

 

ariway

 

Breathing 

Pregnant women have reduced respiratory function and oxygen reserve and are therefore predisposed to rapid changes in oxygen saturations making intubation and ventilation more difficult than in non-pregnant patients

 

breathing

 

Circulation 

Physiological changes in resting heart rate, blood pressure and cardiac output may mask signs of hypovolaemia

 

circ

 

Disability

disab

 

Exposure

fetal ass

 

Secondary Survey

As for non-pregnant patients, once the primary survey has been completed and imminent life threats have been excluded and/or managed then a structured, head-to-toe, front-to-back assessment should be completed

 

sec

 

 

Radiological Investigations

  • uncertainty about the safety of diagnostic imaging in pregnancy result in unnecessary delays and avoidance
  • the risk of radiation to the fetus are small compared with the risk of missed or delayed diagnosis of injury
  • risk to the fetus is dependent on gestational age and radiation dose, with the fetus being most vulnerable to radiation during the first 15 weeks of gestation
  • no cases of fetal goiter or abnormal neonatal thyroid function have been reported in connection with in-utero contrast exposure
  • Gadolinium has known teratogenic effects on animals and is not recommended unless benefits clearly outweigh the risks

 

Increased risks to the embryo or fetus have not been observed for intellectual disability, birth defects, growth restriction, neurobehavioral effects, impaired school performance, convulsive disorders or embryonic or fetal death below an effective dose of 100millisieverts (mSv)

 

rad

 

Continuous Fetal Monitoring 

  • severity of maternal injury may not be predictive of fetal outcome
  • seemingly minor injuries to the pregnant woman can be associated with placental abruption, preterm labor, massive fetal maternal hemorrhage, uterine rupture and fetal loss

 

monitoring

 

Fetal monitoring for FOUR hours is sufficient to rule out major trauma-related complications in patients who have no high-risk features (see table above)

 

Prevention of Rhesus Alloimmunisation

  • traumatic placental injury can result in maternal-fetal haemorrhage (MFH)
  • MFH is estimated to occur in 10 – 30% of pregnant trauma patients
  • Anti-D immunoglobulin should be given to all Rhesus-D negative pregnant trauma patients
  • perform a Keilhauer test to ascertain if additional anti-D doses are required

 

Patient Positioning 

  • after 20 weeks’ gestation supine hypotension from IVC compression from the gravid uterus can reduce cardiac output by up to 30%
  • minimise aortocaval compression by
    • left lateral tilt 15- 30 degrees (i.e. right side up)
    • manual displacement of the uterus

Left lateral tilt 

  • place a firm wedge under the right buttock/hip to achieve a left lateral tilt of 15 – 30 degrees
  • when the patient is immobilised on a spinal board position the wedge beneath the board

 

lat displac1

 

Manual displacement of uterus

  • If lateral tilt is not feasible, use manual uterine displacement to minimise IVC compression
    • can be performed from left or right side of woman:
      • standing on the woman’s left, the uterus (abdomen) is cupped with two hands and pulled towards themselves
      • standing on the woman’s right, the uterus is pushed towards the woman’s left using one hand
    • manual displacement of the uterus is the optimal method of minimising IVC compression in cardiac arrest

 

displ arrest

 

Cardiac Arrest in Pregnancy

  • manage as per standard cardiac arrest algorithms
    • follow standard drug doses, routes and protocols
    • defibrillation as in non-pregnancy
  • avoid femoral or other lower extremity IV lines (if possible) as flow may be affected by vena caval compression
  • consider manual uterine displacement to increase venous return
    • left lateral tilt reduces quality and efficacy of chest compressions
  • remove CTG leads before defibrillating
  • if > 20 weeks’ gestation start preparing for resuscitative hysterotomy (peri-mortem c-section)

 

Resuscitative Hysterotomy

  • is recommended if >20 weeks’ gestation to primarily assist maternal resuscitation and may result in saving the baby if at a viable gestation (>23 weeks)
  • ideally should occur within FOUR minutes of confirmation of arrest
  • trauma patients with cardiac arrest are less likely to respond to resuscitation; in these cases, resuscitative hysterotomy is performed primarily for fetal salvage
  • delivery of a viable neonate is less likely when no maternal vital signs have been recorded for 15 to 20 minutes

 

resus hyst x

 

  • suggested procedure
    • vertical midline abdominal incision or a transverse Pfannenstiel incision.   (whichever the clinician feels will provide the most rapid access)
    • uterine incision may be either vertical or horizontal dependent on gestation and clinician experience

 

Potential Obstetric Complications

 

complications

 

Estimating Gestational Age

Symphysis Fundal Height Measurement 

  • symphysis fundal height in centres approximately corresponds to gestational age in weeks when measured between 16 and 36 weeks’ gestation
  • measure the vertical distance in the midline from the symphysis pubis to the top of the fundus in centimetres
  • the measurement correlates approximately with the gestational age
  • considerations that may impact on accuracy include
    • multiple pregnancy
    • growth restriction
    • poly/oligohydramnios
    • breech or abnormal lie
  • if a tape measure is unavailable fingers breadths may be used as replacement for centimetres
fundal height

 

Rule of Thumb Landmarks

  • 12 weeks: uterus palpable at above the symphysis pubis
  • 20 weeks: uterus palpable at the level of the umbilicus
  • 36 weeks: uterus palpable at the level of the xiphisternum

 

Intimate Partner Violence 

  • consider intimate family violence as a cause of trauma in pregnancy
    • incidence increases during pregnancy, especially in third trimester
    • most struck body area is abdomen
  • offer referral to social workers as appropriate to the circumstances (e.g. intimate partner violence, following fetal demise, if transfer required, for counselling and support)

 

Discharge 

 

dc criteria

 

discharge x

 

References

  1. Emergency Care Institute NSW: Trauma in Pregnancy
  2. Queensland Clinical Guideline: Trauma in Pregnancy (2019).
  3. SOGC Clinical Practice Guideline: Guidelines for the Management of a Pregnant Trauma Patient. Journal of Obstetrics and Gynaecology Canada 2015;37(6):553–571
  4. American College of Emergency Physicians: Trauma in the Obstetric Patient
  5. Practice Management Guidelines for the Diagnosis and Management of Injury in the Pregnant Patient: The EAST Practice Management Guidelines Work Group
  6. Trauma Victoria. Obstetric Trauma Guideline.

 

About this guideline

Published: October 2024
Author: Jonathan McMillian

Approved by: Service Clinical Directors of the Adult Emergency Department, Secondary Maternity, Trauma Service and the Director of Midwifery at Auckland City Hospital

And Northern Region Trauma Network, Health New Zealand | Te Whatu Ora – Northern Region, NRHL, St. John


Review due: 2 years