Two for the Price of One Trauma in Pregnancy

1. Two for the Price of OneTrauma in Pregnancy Michael P. Sloan, MD University of Wisconsin General Surgery

2. Why talk about pregnancy? • Secret desire to be an Obstetrician

3. Why talk about pregnancy? • Secret desire to be an Obstetrician • Fear of my pregnant patients

4. Why talk about pregnancy? • Secret desire to be an Obstetrician • Fear of my pregnant patients • Too many shoulder shrugs from residents when asked to see a pregnant patient

5. Why talk about pregnancy? • Secret desire to be an Obstetrician • Fear of my pregnant patients • Too many shoulder shrugs from residents when asked to see a pregnant patient • Opportunity to review the topic and share my thoughts

6. Why this matters? • 4 million pregnancies occur in the US each year • Approximately 2% will require surgery during pregnancy • 1 in 500 will be complicated by a “General Surgery” condition • Maternal mortality < 0.01% • Miscarriage rate between 5-11% with operative intervention * • Absence of education in Surgical and Obstetric training programs * Cohen-Kerem et al

7. Trauma Specifics • 1.5% of women hospitalized after injury are pregnant • Fetal:Maternal Death Ratio (3:1 – 9:1) • 6-7% of all pregnant women experience an “accidental injury” • MVC 70% • Pelvic fracture associated with fetal mortality up to 35% • Interpersonal violence 11.6% • GSW results in fetal mortality of 40-65% • Falls 9.3% NTDB 2005 Trauma 6th Ed. Feliciano et al

8. Risk factors for Loss of Pregnancy after Trauma • ISS > 15 9.17 • GCS < 8 5.24 • AIS > 3 • Head 3.02 • Chest 2.29 • Abdomen 5.63 • Lower Extremity 3.98 Ikossi DG et al. JACS 2005

9. Objectives • Physiology of Pregnancy • Imaging Considerations • Anesthesia and Medication • Assessment and Triage • Building Your Team

10. What makes the pregnant patient difficult? • Pathology and physiology merge • Nausea, vomiting, reflux, pain • Leukocytosis, anemia • Tachypnea, tachycardia • Patient and Physician fear • Eating for two versus cutting for two

11. Cardiovascular Physiology • Cardiac Output increases 50-100% • Decreased venous return • Systemic Vascular Resistance down 15% • Physiologic hypervolemia of pregnancy may mask shock • Baseline blood pressure typically down • Supine hypotensive syndrome (10-15 mmHg)

12. Respiratory Physiology • Minute Ventilation up 50% • pCO2 typically 30 mmHg • Compensatory alkalosis • Functional Residual Capacity down 20% • Elevated diaphragm • Edematous change of the airway • Difficult intubation and higher chance for bleeding

13. Physiology • Hypercoagulable (DVT/PE) • Delayed gastric emptying • Prolonged intestinal transit time • Constipation • Decreased lower esophageal sphincter pressure • Blood volume increases 40-55% • Relative anemia (Hct down 30% by term) • Renal blood flow up 50-80% • Increased renal excretion of drugs * Goodman, S

14. Pregnancy Fundamentals • When presented with a surgical problem in a pregnant patient, start with the understanding of the problem’s treatment in the nonpregnant patient. • In general, what is good for mom is good for baby.

15. Imaging

16. Just another X-ray • Use of radiographic studies at an all time high • Increasing data to support long term risks of cumulative radiation • Possible oncogenic effects of exposure at an early age • The data is terrible

17. Reference Data

18. Radiology Basics • X-rays and gamma rays ionize atoms and molecules through deposition of energy • Step one of potential biologic/genetic effect • Dose of interest is absorbed dosage • Typically energy imparted per unit mass • One Gray = 1000 milligray = 100 rad = One Joule per kilogram

19. Fetal Effects • Teratogenicity • No evidence of increased congenital malformation when < 50 mGy • Based upon animal and human data • Closely correlates to Gestational Age at exposure • Genetic damage • Risk of genetic disease at 10 mGy is between 0.012 and 0.099% • Based upon Hiroshima survival data • Oncogenicity • Data remains mixed • Epidemiologic studies which often fail to show significance

20. Fetal Effects • Intrauterine death • Rat embryo data shows maximum 10% mortality at 30 rads (300 mGy) and 65% mortality at 150 rads • Japanese and Chernobyl data could not confirm higher mortality • Growth retardation • Decreased head circumference, height, and weight at 25 rads • Based upon in utero exposure to Japanese atomic blasts * Lowe, SA

21. Typical X-ray and CT Based upon ACOG and ACR recommendations, exposure should be limited to < 5 rad (<50 mGy) * Melnick, DM et al. * Lowe, SA

22. US, MRI and NM • Ultrasound considered safe throughout pregnancy • MRI appears safe • ACOG recommends avoidance in 1st Trimester • ACR suggests consultation with Radiologist • MRI contrast considered Pregnancy Class C • Nuclear Medicine • Limited use in trauma assessment * Toppenberg, KS et al.

23. ACOG Guidelines • Ultrasound considered safe throughout pregnancy • CT/x-ray/fluoroscopic imaging • Fetal risks of anomalies, growth restriction, or abortions are not increased with radiation exposure of less than 5 rad • When possible consult with expert in dosimetry and adjust (consider protocols for pregnant patients) • MRI appears safe • ACOG recommends avoidance in 1st Trimester • ACR suggests consultation with Radiologist • MRI contrast considered Pregnancy Class C * ACOG Committee on Obstetric Practice 2009.

24. American College of Radiology No single diagnostic procedure results in a radiation dose that threatens the well-being of the developing embryo and fetus. * www.acr.org

25. Imaging Recommendations • Use when necessary • Most important in Trauma • Consult Radiologist • Adjust dosimetry • Informed Consent • <1 mGy = negligible risk • 1-10 mGy = theoretical cancer data • >10 mGy = risk versus benefit

26. Medications & Anesthesia

27. Pharmacology • Volume of distribution increases • Relative hypoalbuminemia • Renal clearance increases • Pharmacokinectics and phamacodynamics are heterogenous

28. Drug Summary • Most analgesics are Category C • No inhalation anesthetic agents have been linked to human teratogenicity or fetal demise • Typically Category B or C • Benzodiazepines are Category D • Propofol is Category B • Heparin is Category C, whereas warfarin is Category X

29. Current Categories for Drug Use in Pregnancy A = Adequate, well-controlled studies in pregnant women have not shown an increased risk of fetal abnormalities. B = Animal studies have revealed no evidence of harm to the fetus, however, there are no adequate and well-controlled studies in pregnant women.orAnimal studies have shown an adverse effect, but adequate and well-controlled studies in pregnant women have failed to demonstrate a risk to the fetus. C = Animal studies have shown an adverse effect and there are no adequate and well-controlled studies in pregnant women. or No animal studies have been conducted and there are no adequate and well-controlled studies in pregnant women.

30. Current Categories for Drug Use in Pregnancy D = Studies, adequate well-controlled or observational, in pregnant women have demonstrated a risk to the fetus. However, the benefits of therapy may outweigh the potential risk. X = Studies, adequate well-controlled or observational, in animals or pregnant women have demonstrated positive evidence of fetal abnormalities. The use of the product is contraindicated in women who are or may become pregnant.

31. Drug Summary • Observe Categories for Drug Use in Pregnancy • Adult dosing typically applies • Use weight base formulas when necessary • Antibiotics • Anticoagulation • Consult your pharmacist

32. Anesthesia Recommendations • Maintain adequate uteroplacental perfusion • Avoid and treat hypotension • Avoid aortocaval compression • Use regional anesthesia if possible • Although no data exists to support this approach • Counsel patient • No evidence for increased fetal loss or teratogenic effect from anesthesia alone • Fetal monitoring when feasible * Kuezkowski, KM

34. Fetal Loss • Estimated 10-15% loss in normal pregnancy after clinical recognition (4 to 6 weeks) • Failure of implantation may occur in 50-70% of pregnancies (unrecognized) • Spontaneous abortion rates drop to 2-3% after 8 weeks Gestational Age • Overall reported miscarriage rates of 5.8% in patients undergoing nonobstetric operation • 10.5% in 1st Trimester * Cohen-Kerem, R et al.

35. Operative Strategies • Fetal monitor for Gestational Age > 24 weeks • Left lateral recumbent positioning will minimize caval compression • Standard application of pneumatic compression devices • No data for use of SQ heparin or LMWH in pregnant patients for prophylaxis • Prophylactic tocolytics are not justified • Use should be individualized

36. Assessment and Triage

37. ATLS “The doctor attending a pregnant trauma victim must remember that there are two patients. Nevertheless, initial treatment priorities for an injured pregnant patient remain the same as for the nonpregnant patient.” ACS Committee on Trauma

38. Incidence and Etiology • #1 cause of maternal death in pregnant population • Estimated to occur in 1 in 12 pregnancies • Physical abuse significantly underreported * Mattox, KL et al.

39. Fetal Injury • Most dependent on maternal outcome • Degree and Duration of hypotension • Injury Severity Score and Base Deficit • Fetal shock can occur in normotensive mother • Fetal death • MVC 82% • Penetrating injury 6% • Falls 3% • Maternal death 11% • Abuse ???

40. Initial Assessment • ABCs • Left lateral position with spine stabilization • Focused abdominal sonography for trauma (FAST) • 83% sensitive in pregnant population • Avoids ionizing radiation • May identify unrecognized pregnancy • Trauma labs • Routine assessment • Recognize variation in “Normal” in pregnancy • Kleihauer-Betke test (fetal blood in maternal circulation) • Rh immune globulin

41. Radiographic Evaluation • Use when necessary • Minimize ionizing radiation (<5 rads) • CT scan A/P (2-7 rads) • Experience matters • Radiologist involved in assessment • FAST versus Abdominal Ultrasound • Limit exposure by varying protocols

42. Fundal Height • 8 weeks – palpable above pubis • 12 weeks - half way between pubis and umbilicus • 20 weeks - umbilicus • 32 weeks - half way between umbilicus and xyphoid Rozycki GS et al Hosp Physician 1989

43. Obstetric Consultation • Fetal monitor after initial survey or recognition of pregnancy • Utility questioned in nonviable pregnancy (<24 weeks) • May detect uterine contractions (tocolytics) • Emergent Cesarean Section • Considered at 24 weeks GA • 45% fetal survival • 72% maternal survival • Perimortem if less than 5 minutes since maternal arrest

44. Fetal Exam • Obstetrician if possible • Speculum/Bimanual • Assessment includes: • Vaginal bleeding • Amniotic fluid/Rupture of membranes • Bulging perineum • Presence/Absence of contractions • Fetal heart rate and rhythm • Cardiotocographic monitor

45. Postmortem Cesarean Section • Time between maternal death and delivery <5 minutes, excellent outcome 5-10 minutes, good 10-15 minutes, fair 15-20 minutes, poor >20 minutes, unlikely to survive Higgins, SO J Perinatology 1988

46. Procedural Information • Establish Viability • Initiate CPR on maternal patient • Vertical midline incision in abdominal wall and uterus • Clamp cord and deliver • Remove placenta • Continue CPR and reassess maternal viability

47. Team Building • Know your resources • Identify key players • Obstetric services • Equipment needs • Field triage and referral • Rely on routine trauma experience • Consider protocols/guidelines • ED/Radiology/Surgery/OB-FM-Pediatrics

48. Questions, Comments, or Bright Ideas