Dr. Joe Haegert RCH and ERH SPH Conference 2013 Obstetrical Trauma Dr. Joe Haegert RCH and ERH SPH Conference 2013

Main message Two patients Focus mainly on resuscitating mother

Overview Physiologic differences Anatomic differences Pregnancy Specific Issues: Abruptio Placenta PROM Ruptured Uterus Supine Hypotensive Syndrome Rh negative mothers and KB testing Imaging in pregnancy Management algorithms Mother stable, Fetus stable Mother stable, Fetus unstable Mother unstable, Fetus unstable Perimortem C section

Case 1 22 yr old female shot in head and chest 32 weeks pregnant GCS 3, BP 70/P, P 100 Fetal heart rate of 50

Case 2 32 year old female 34 weeks pregnant MVA head on GCS 14, P 110, BP 80/P Severe chest trauma Bilateral femur # Fetal heart rate 170

Case 3 39 weeks pregnant T bone MVA 20 inches intrusion Airbags deployed Stable vitals, GCS 15, mild chest pain and neck pain, no abdominal pain Cspine and CxR and FAST normal FHR 140

Intro Trauma is leading cause of nonobstetrical death in pregnancy (mvas, falls, assault) 7% of pregnancies will have trauma 8% of female trauma admits of child bearing age do not know that they are pregnant Severity of maternal injuries is a poor predictor of fetal distress and outcome Trauma in pregnancy is associated with increased risk of: - - preterm labor - abruptio placentae - fetomaternal hemorrhage - fetal death

Incidence of trauma increases with gestational age Most maternal deathes are due to HI or hemorrage

Cause of fetal death With severe maternal trauma the baby dies because of maternal death or maternal hemorrhagic shock With mild maternal trauma the baby dies because of abruption

Physiologic Differences Hypoxia decreases uterine flow Lower FRC and increased metabolic rate increased risk of hypoxia O2 therapy on all lower threshold for intubation Acidosis decreases uterine flow Normal PC02 runs 30-35 No role for permissive hypercapnia Set vent rate faster than normal Decreased lower esophageal sphincter pressure and increased gastric acidity Regard all intubations as high risk for aspiration Increased airway edema and secretions Have smaller ETT ready Increased thrombogenesis DVT prophylaxis for admitted trauma patients

Physiologic Differences Hypervolemia with dilutional anemia (40% increased BV) Compensated (i.e. unrecognized) shock more common Shock (including compensated shock) causes uterine artery constriction Volume resuscitate aggressively BP lower in 2nd trimester, higher in 3rd trimester Diagnosis of shock a bit more tricky Uterus has increased blood flow (entire blood volume in 10 minutes) Abruptio placentae and Uterine rupture can bleed massively Pelvis has increased blood flow Increased risk of massive pelvic hemorrhage Increased venous pressure in legs Increased bleeding from leg injuries Vasopressors constrict the uterine artery Avoid vasopressors

Anatomical Differences Large uterus: 12 weeks at symphysis 20 weeks at umbilicus 36 weeks at xiphoid process pelvis not protective after 12 weeks femoral line not the best option supine hypotensive syndrome after 20 weeks Compression of upper abdominal viscera stab abdomen may hit many structures Widened symphysis pubis be aware that this may be normal….not open book # Higher diaphragm Heart displaced up and to left place chest tube 2 interspaces higher There is a baby! initiate fetal monitoring early baby can be injured

Supine hypotensive syndrome > 20 weeks gest. Can decrease venous return up to 45% Systolic BP can drop by as much as 30mm Place wedge under right hip displacing uterus to the left (left lat tilt position)

Amniotic Fluid leakage (PROM) Vaginal exam on all major pregnant trauma PH greater or equal to 7 suggests amniotic fluid Ferning also suggestive of amniotic fluid Oligohydramnios on ultrasound Increasing risk with gestational age and trauma severity

Imaging in pregnancy Image as if patient nonpregnant Highest risk of radiation induced fetal injury in first 2 weeks Concerns are death, congenital malformation, teratogenesis, carcinogenesis, mental retardation Over 200ms may cause fetal damage, still unclear the long term cancer risk Ultrasound and MRI are safe in pregnancy

Radiation risk Background………………….. 3mSv/yr 10 hr flight………………… 0.03mSv CxR………………………….0.01mSv CT head………………………. 2 mSv CT neck………………………..4mSv CT chest……………………….4mSv CT abdomen/pelvis.……….. 7 mSv Pan CT………………………...17mSv So none of these is close to the dangerous 200mSv

So what is my approach to blunt abd trauma in pregnancy? Unstable and positive FAST or peritonitis………………………….OR Stable and positive FAST………..CT Stable and negative FAST………..US + Observ

Obstetrical complications of trauma Fetomaternal hemorrhage Abruption Preterm labour Fetal Injury Uterine rupture Amniotic fluid embolism

Kleihauer Beikte test Calculates degree of feto maternal transfusion Uses: 1) Rh negative mother 2) To access degree of fetomaternal transfusion

RHIG and Tetanus RHIG 300ug….will protect up to 30ml fetomaternal hemorrhage Dose guided by KB test Have up to 72 hours to give it Give RHIG to all Rh neg mothers even if negative KB test Dose is 50ug in first trimester (or 300ug ) Tetanus and TIG are NOT contraindicated in pregnancy

Placental Abruption Can be occult Triad: pain, hardness of uterus, vag bleeding 70% of fetal loss comes from placental abruption Is a clinical diagnosis….ultrasound not sensitive Coagulopathy rare

Risk of abruption Usually happens within 4-6 hours Risk: minor trauma 1.6% (but minor trauma is common) major trauma 37.5%

Fetal Injury Abruption is commonest cause of death Maternal shock is next Direct fetal injury less common - pelvic # 9% maternal death rate, 40% fetal death rate - penetrating uterine trauma: fetal injury 60-90%(gsw worse than stab), fetal mortality 40-70%

Traumatic Uterine Rupture Usually presents with shock and hemoperitoneum Consider in setting of free fluid and high riding dead baby Commonest is a fundal tear Maternal mortality 10% Fetal mortality 100%

Preterm Labour Abruption Fetomaternal hemorrhage Rupture of membranes Fetal distress Maternal Shock Abnormal Fetal monitoring

Dating At 20 weeks uterus at umbilicus. At 24 weeks = umbilicus + 4 cm At 36 weeks at xiphoid process Symphysis to fundus in cm = # weeks So key # is SFH>24 or umbilicus to fundus of >4 Ultrasound: BPD, OFD, FL, HL, HC, AC

Fetal Monitoring Recommended that all trauma patients > 24 weeks be monitored for 4-6 hours If normal monitoring for 4 hours this is >90% predictive of positive fetal outcome If patient is critical (i.e. in ICU) then continuous monitoring is indicated Start monitoring on arrival to ED if patient badly injured /major mechanism

Fetal Monitoring: abnormal Fetal heart rate outside normal range of 120-160 Greater than 3 contractions per hour Lack of beat to beat variablity Fetal decelerations with contractions Indications for prolonged FM - abnormal 4 hour FM - uterine pain persists - vaginal bleeding or amniotic fluid leakage -mother unstable

Clinical scenarios > 24 weeks Mother stable, Baby stable Mother stable, Baby unstable Mother unstable, Baby unstable Perimortem C section

Mother stable, Fetus stable 1-3% of minor trauma leads to fetal death For patients less than 24 weeks….no FM For patients > 24 weeks…CFM for 4 hours with OB consult Discharge criteria and advice

Mother stable, Fetus unstable Less than 24 weeks….no C section Greater than 24 weeks….C section….exact # weeks is site dependent Obviously this is a OB decision and likely not and EP’s decision

Mother Unstable, Fetus Unstable First priority is the mother If despite good resuscitation there is fetal distress…AND… patient over 24 weeks…AND it is thought that the CS will not make the mother clinically deteriorate…consider CS If fetus has no FHR there is no indication for emergency CS

Perimortem C section Indications - over 24 weeks gestation - intact fetal heart rate on ultrasound - maternal pulselessness or - fetal distress in a mother with injuries that are likely to be fatal (i.e. severe head injury,)

Perimortem C section Procedure Incision from xiphoid to pubis Longitudinal uterine incision Get baby out (5 min rule…from time of maternal arrest) Clamp cord Give baby to infant resus. team

Prevention Seat belts: - Air bags: Screen for domestic violence Educate re: increase risk of falls in 3rd trimester

Summary of treatment differences Early oxygen Intubate early Early fetal monitoring Place on left lat tilt position over 20 weeks Call Ob early

Summary of treatment differences Beware compensated shock can cause fetal distress Avoid pressors Avoid acidosis Chest tubes higher Neck or subclavian lines best

Summary of treatment differences Don’t forget about KB test and RHIG Do not withhold CT if it is indicated Perimortem C section…know when to pull the trigger….and how to do it If baby viable and minor trauma.. do 4 h fetal monitoring

Main take home message 2 patients Focus on resuscitating the mother Best chance of baby doing well is the mother doing well

Case 1 22 year old female, 32 weeks pregnant, shot in head and chest with fetal P 50 Perimortem C section

Case 2 32 yr old female, 34 weeks with chest trauma, bilateral femur fractures and hypotension Resuscitate the mother!!

Case 3 39 week pregnant female with moderate vehicle damage, but clinically stable Needs 4 hour FM and then discharge if OK