Caring for Mom and Child: Trauma in the Pregnant Patient

Transcription

1 Caring for Mom and Child: Trauma in the Pregnant Patient George Koenig DO, FACS Assistant Professor of Surgery, Division of Trauma & Critical Care Associate Medical Director JeffSTAT Thomas Jefferson University Hospital

2 Case #1 30 y/o F, 35 weeks gestation, MVC Driver, belted, rear ended by another car, airbag deployed, complains of occasional abdominal cramping, unsure about fetal movements, very concerned about fetal well being PMH: none PE: 110/70, HR 90, RR 22 No signs of injury on exam, FHR 140, no guarding, no seatbelt sign, no vaginal bleeding

3 Case #2 25 y/o F, 30 weeks gestation, struck by a truck across the street from the hospital. Cardiac arrest at scene. Resuscitation started after 5 minutes down time. PEA on arrival in ED

4 Why Is This Important? Leading cause of non-obstetric mortality 46% Incidence of trauma during pregnancy 7% Causes of Trauma MVC 55% Domestic Violence 22% Falls 21% Penetrating Injury 1.3% Less than 1% of trauma admission are pregnant Preterm labor 11% and Placenta abruption 2%

5 Why Is This Important? Trauma in pregnancy presents unique challenges Physiologic and anatomic changes of pregnancy change the pattern of injury and the physiologic response to injury Two patients Both of which require treatment!! Emotional issues (we re all human)

6 But.. ATLS Protocol is the SAME Focus on the mother NOT on the fetus What is BEST for the mother is BEST for the fetus

7 Physiologic Changes - Cardiovascular Heart rate Increase 15 bpm beginning in 1 st trimester Systolic and diastolic blood pressure Decrease by a mean of 10 mmhg Reduced SVR, starts to rise after 28 weeks back to baseline Cardiac output

8 Physiologic Changes Blood Volume and Composition 40% increase in blood volume 25% increase in red cell mass Dilutional anemia Greater rise in plasma volume compared to red cell volume Normal can be as low as Hb The mother may loose up to 1500 ml of blood without hemodynamic instability BUT the fetus may be in SHOCK!!

9 Physiologic Changes - Pulmonary Tidal volume and respiratory rate Can have physiologic hyperventilation with a compensatory metabolic acidosis PaCO2 is low and HCO3 is low Decrease in functional residual capacity (20%) and increased O2 consumption (15%) Impaired buffering capacity

10 Physiologic Changes - GI Risk of Aspiration Increased intra-abdominal pressure Hormone mediated relaxation of the LES Hormone mediated decrease in gut motility can lead to a physiologic ileus

11 Physiologic Changes - Renal Glomerular Filtration Rate BUN and Creatinine Glycosuria common Mild hydronephrosis due to uterine compression of the ureters

12 Anatomic Changes

13 Changes and Risks First trimester Uterus is intrapelvic and thick-walled Fetus is protected from direct injury Risks Abortion Isoimmunization ATLS 2013

14 Changes and Risks Second Trimester Uterus is extrapelvic Large volume of amniotic fluid Risks Placental abruption Amniotic fluid embolism Isoimmunization ATLS 2013

15 Changes and Risks Third Trimester Uterus is thin-walled Maternal abdominal viscera displaced IVC compression Risks Pelvic fractures with maternal hemorrhage and direct fetal injury Placental abruption Amniotic fluid embolism Isoimmunization ATLS 2013

16

17 Inferior Vena Cava Compression Uterus reaches level of umbilicus by 20 weeks gestation and is large enough to compress the IVC Results in 30% reduction in cardiac output Results in significant fall in stroke volume that can lead to hypotension and malperfusion Displacing the uterus to the LEFT is CRITICAL!!

18

19 Musculoskeletal Changes Hormone mediated relaxation of sacroiliac joints Widening of symphysis pubis

20 Injuries Unique to Pregnancy Premature Contractions Very common Uterine contusion Rarely progress to preterm delivery Tocolytics not proven in trauma GoodwinTM, Breen MT: Pregnancy outcome and fetomaternal hemorrhage after noncatastrophic trauma, Am J Obstet Gynecol162: , 1990.

21 Injuries Unique to Pregnancy Placental Abruption Most common blunt injury Up to 50% in severe trauma, 3% minor trauma Shearing effect and separation between placenta and the uterus Flexible myometrium / inflexible placenta May have vaginal bleeding and tenderness Fetal monitoring most sensitive for fetal distress U/S specific but not sensitive, detects 50% of the cases

22 Uterine Rupture Rare (0.6%) severe trauma Typically after 12 weeks gestation Prior surgery increase risk Maternal-Fetal Hemorrhage Increases with trimester (3%, 12%, 45%) 4-5x more common in injured pregnant women Causes isoimmunization and fetal death Rhogam for rh- mother

23 Blunt Trauma Injuries Head injury is most common Retroperitoneal hemorrhage Pelvic organs and vessels increased in size Placental abruption DIC Release of stored thrombolytic factors may precipitate DIC Uterine Rupture Near 100% fetal mortality Site of previous C-section

24 Seat belts Between 1/3 and 1/2 are improperly used or not used Unbelted Increase likelihood 2.3x of giving birth <48hrs Fetal death 4.1x more likely

25 Penetrating Injury Gravid uterus alter injury pattern to mother Enlarged uterus reduces the risk of hollow viscus injury from penetrating lower abdominal trauma by displacing the bowel cephalad and laterally. However, penetrating trauma above the uterine fundus is MORE likely to damage bowel. The enlarged uterus shields retroperitoneal structures from penetrating abdominal trauma.

26 Primary Survey and Risks A B C D Aspiration risk Difficult ventilation Failure to recognize blood loss early Eclampsia With maternal blood loss, fetal distress precedes changes in maternal vital signs. ATLS 2013

27 Eclampsia Seizures Hypertension, hyperreflexia, proteinuiria, peripheral edema May mimic HEAD INJURY in the trauma patient

28 Evaluation and Management How do I evaluate and treat two patients? Primary survey / resuscitation of mother Fetal assessment Secondary survey of mother Definite care of mother and fetus Rh-negative mothers receive immunoglobin therapy (unless injury remote from uterus) Early OB consult ATLS 2013

29 The Mother A B C D E Same as nonpregnant Same as nonpregnant Caution chest tube placement Displace uterus and volume infusion Caution fetal shock Eclampsia vs. brain injury Same as nonpregnant

30 The Fetus Resuscitate the mother Monitor fetal heart tones Consider fetal injury Vaginal bleeding Placental abruption Uterine tenderness Uterine rupture Labor

31 What if Trauma is Minor? If after primary and secondary survey, maternal injury consists of minor bruising, abrasions, or contusions AND the patient has no abdominal pain: NO Laboratory evaluation required NO Radiologic imaging required Brief fetal assessment with ultrasound is usually sufficient Discharge with appropriate counseling and outpatient OB follow-up

32 In 2008, prospective trial, researchers looked at 317 patients with minor trauma Placental abruption occurred in only 1 case The abruption was NOT predicted by ultrasound, tocodynamometry, CBC, Kleihauer-Betke testing, or coagulation profile Authors concluded that minor trauma can be evaluated with limited assessment Am J Obstet Gynecol Feb;198(2):208.

33 But What if Trauma is Significant? One of the biggest concerns in the care of the pregnant patient is. RADIATION

34 Preconceived Notions How can you image a pregnant patient? Won t the radiation harm the baby? Will the baby have a deformity? Will the baby get cancer? What kind of terrible, horrible person would ever RADIATE a pregnant woman?

35 We know from investigating survivors of atomic bomb blasts and the Chernobyl spill that ionizing radiation can lead to: Pregnancy loss Malformation Disturbance of growth or development Mutagenic and carcinogenic effects Depends on gestational age, dose, and repair mechanisms

36 Radiation Exposure Measurement Rad (radiation absorbed dose) Grey (1 rad = 1 centigy; 100 rads = 1 Gy) Greatest effects of radiation exposure occur between conception and week 25 Radiation injury during weeks 1-3 results in death of the implant or embryo Radiation during weeks 8-25 affect CNS 10 rads may result in decreased IQ 100 rads may result in severe mental retardation Mettler FA, Brent RL, Streffer C, et al. Pregnancy and medical radiation. Ann ICRP 2000;30:1-42.

37 Radiation Exposure After 25 weeks, greatest risk is childhood hematologic malignancy Background incidence is % Risk increases to % if exposure > 1 Gy Risk increases by 0.06% per 1 Gy of fetal exposure Risk negligible < 5 rads exposure Risk increases > 15 rads exposure Most diagnostic procedures have no measurable risk Therapeutic procedures have greatest risk Mettler FA, Brent RL, Streffer C, et al. Pregnancy and medical radiation. Ann ICRP 2000;30:1-42.

38 Approximate Fetal Radiation Dose Study Dose (rads) Chest X-ray <0.001 Pelvis 0.04 CT Head <0.05 CT Chest CT Abdomen CT Pelvis Spine series month 0.1 background dose

39 Radiation Exposure - Summary There is NO evidence of an increased risk of fetal anomalies, intellectual disability, growth restriction, or pregnancy loss from ionizing radiation at does less than 5 rads NONE!!! There is NO strong data to suggest that exposure between 5 and 10 rads in dangerous The vast majority of reasonable radiographic evaluations will be below this threshold IF the MOTHER needs the STUDY, GET IT

40 Other Diagnostic Modalities MRI Excellent quality images of maternal organs and provides some information about the fetus Limited by length of exam, inability to quickly access the patient, and availability of machine

41 Ultrasound Mainstay in the evaluation of the pregnant patient Good sensitivity for fluid in most cavities (especially abdomen and chest) Portable No radiation

42 FAST Examination

43 RUQ

44 Pericardium

45 LUQ

46 Pelvis

47 Fetal Monitoring

48 Prompt fetal evaluation and intervention critical Study of 441 pregnant women presenting to Level 1 trauma centers (91% blunt and 9% penetrating) 32 women had emergent C-section for fetal distress Fetal survival 45% Maternal survival 72%

49 NO Fetus with absent fetal heart tones survived emergent delivery, while 75% of those with fetal heart tones and gestational age >26 weeks survived 5 infants with fetal heart tones at presentation did not survive 3 of these infant deaths likely resulted from delayed recognition of nonreassuring fetal heart rate patterns for greater than 2.5 hrs

50 Cesarean Delivery Urgent cesarean delivery may be necessary in the pregnant trauma patient if: Imminent maternal death Baby cannot survive WITHOUT mother Mother cannot survive WITH baby Cardiopulmonary resuscitation that has been no effective within 4 minutes Stable mother with nonreassuring fetal heart rate tracing If necessary for repair of maternal injuries blocked by gravid uterus

51

52 Perimortem Cesarean Delivery Reviews of perimortem cesarean delivery suggest optimum infant and maternal survival are obtained: When cesarean delivery is initiated within 4 minutes of maternal cardiac arrest When the fetus is delivered within 5 minutes of unsuccessful resuscitation attempts

53 Rationale for 5 minute rule Irreversible brain damage can occur in nonpregnant individuals after 4 6 minutes of anoxia Pregnant women become anoxic sooner than nonpregnant women because of reduced functional residual capacity Fetal survival diminishes as the time between maternal death and delivery lengthen If uterine fundus is >4 fingerbreadths above the umbilicus, ineffective resuscitation efforts may become effective when uterus is no longer gravid and potentially causing aortocaval compression

54 Cardiac Arrest Data Very little data on outcomes after emergent cesarean delivery for trauma Most data comes from cardiac arrest In a 5 case series Maternal fatality rates for cardiac arrest were 40 to 83% Fetal fatality rates are 11 to 58% Survival of the mother and neonate depended upon underlying etiology for the arrest, maternal location (out of versus in hospital), speed of resuscitative efforts, and skills and resources of healthcare providers

55 Multicenter study reported outcomes of 55 women with a cardiac arrest during pregnancy 15% of women survived 12 women underwent perimortem c-section 5 infants (42%) survived (none were delivered within the recommended 4-5 minutes Those who underwent c-section were NOT more lively to survive 17% vs. 14% (not significant)

56 Summary

57 Summary Primary Survey Stage of Resuscitation Secondary Survey SAVE THE MOTHER FIRST!!! Limit fetal radiation to 5 rads Limited role for emergency cesarean section