Trauma in Pregnancy 1 Flashcards

A 30-week pregnant trauma patient is placed supine on a long backboard for spinal precautions. In addition to treating for shock, what modification to her positioning is recommended by ITLS to optimize hemodynamics?

Answer: Tilt the entire backboard 15–30 degrees to the left to relieve aortocaval compression

The gravid uterus compresses both the inferior vena cava and the aorta when the patient is supine, reducing venous return and cardiac output. Tilting the backboard 15–30 degrees to the left (or manually displacing the uterus leftward) relieves this compression without compromising spinal precautions.

A 34-week pregnant patient involved in a moderate MVC has a heart rate of 116 bpm, pale skin, and a blood pressure of 114/72 mmHg. The fetal heart rate is 94 bpm. How should you interpret this clinical picture?

Answer: Early compensated maternal hemorrhagic shock — the fetus is already showing distress before maternal BP drops

Pregnant patients expand their blood volume by 40–50%, allowing them to compensate for significant hemorrhage while appearing relatively stable. However, the fetus receives reduced perfusion much earlier, manifesting as fetal bradycardia (normal FHR is 120–160 bpm). A fetal HR of 94 bpm signals fetal distress even when the mother's BP appears acceptable.

During the secondary survey of a 38-week pregnant trauma patient, you note sudden relief of her abdominal pain, diffuse rigidity across the entire abdomen, fetal parts palpable through the abdominal wall, and absent fetal heart tones. Which condition does this presentation most likely represent?

Answer: Uterine rupture

Uterine rupture is characterized by a sudden 'pop' or relief of pain as uterine wall integrity fails, followed by diffuse peritoneal irritation as blood and fetal contents spill into the abdomen. Fetal parts become palpable through the abdominal wall and fetal heart tones disappear. This is a life-threatening surgical emergency requiring immediate transport.

An Rh-negative pregnant patient at 28 weeks is assessed after a low-speed MVC with minor abdominal wall contusion. Her vital signs are stable and fetal heart tones are normal. What critical piece of information must you relay to the receiving facility team regardless of apparent injury severity?

Answer: She must receive Rh immunoglobulin (RhoGAM) within 72 hours to prevent Rh sensitization

Even minor trauma can cause fetomaternal hemorrhage, allowing fetal Rh-positive red blood cells to enter the Rh-negative mother's circulation. This sensitizes her immune system to produce anti-Rh antibodies that can destroy red blood cells in future Rh-positive pregnancies. RhoGAM administration within 72 hours of the event prevents this sensitization.

When assessing a third-trimester pregnant trauma patient's airway and breathing, which anatomical change of advanced pregnancy most significantly increases her risk of rapid oxygen desaturation during apnea or assisted ventilation?

Answer: Elevation of the diaphragm by the gravid uterus, reducing functional residual capacity

The gravid uterus displaces the diaphragm superiorly by up to 4 cm, significantly reducing functional residual capacity (the oxygen reserve in the lungs between breaths). Combined with a 20% increase in oxygen consumption driven by the fetus and placenta, pregnant patients desaturate far more rapidly than non-pregnant adults during any period of apnea or inadequate ventilation.

A pregnant patient at 32 weeks is in hypovolemic shock after trauma and requires IV fluid resuscitation. Which physiologic consideration is most important when interpreting her hemoglobin and hematocrit values obtained at the receiving facility?

Answer: Dilutional anemia of pregnancy means a hematocrit of 31–35% may be her normal baseline, not a sign of acute blood loss

Plasma volume expands by approximately 50% during pregnancy while red blood cell mass increases by only 20–30%, producing a physiologic dilutional anemia. A hematocrit of 31–35% or hemoglobin of 10–12 g/dL may represent the patient's normal pregnant baseline rather than acute hemorrhage. Trending values and clinical signs of perfusion are more reliable than a single lab snapshot.