Prehospital care of the pregnant patient during the second half of pregnancy can be a challenging and anxiety provoking experience for the EMS physicians and providers. First and foremost, two patients are involved: the mother and the viable fetus. Secondly, this situation is not frequently encountered and therefore familiarity with the situation, potential complications, and treatment options may not be at the forefront of the provider's mind. The assessment and treatment of the pregnant patient should therefore be regularly reviewed. The goal of this section is to provide a review of the assessment and treatment of the most common issues of this unique patient population when they seek emergent care.
Prior to a discussion of the emergent conditions the gravid patient may face, an understanding of the basic physiological changes encountered in pregnancy is necessary. A number of changes involving the cardiovascular system take place in pregnancy. A pregnant woman can have 50% more blood volume than that of the nonpregnant women,2 equating a volume of approximately 1500 mL. Also, heart rate and stroke volume increase, causing a physiologic tachycardia of pregnancy. The pregnant patient can have a heart rate 10 to 15 beats per minute above normal. While cardiac output increases, a decreased peripheral vascular resistance actually lowers the pregnant women's blood pressure. Lastly, venous return to heart in the supine position during the third trimester of pregnancy is compromised due to the gravid uterus resting on the inferior vena cava and decreasing cardiac preload, a phenomenon known as supine hypotensive syndrome. Pregnant patients must be placed on their left side to alleviate this syndrome. If immobilized after a trauma, the backboard should elevated on the right to allow the fetus to move to the left and improve venous return. All of these common physiological changes should be considered when assessing the pregnant patient.
Assessment of blood pressure, particularly hypertension, is of particular importance. Hypertension affects approximately 12% of pregnancies and contributes to approximately 18% of maternal deaths in the United States annually.3 Hypertension during pregnancy is defined as a blood pressure of 140/90 mm Hg, a 20 mm Hg rise in systolic blood pressure or a 10 mm Hg rise in the diastolic pressure. Different categories of hypertension affect pregnancy. Patients with an established history of hypertension prior to the pregnancy have chronic hypertension. Hypertension that is mild develops in the third trimester and does not adversely affect the pregnancy is transient hypertension. Preeclampsia is the combination of hypertension and proteinuria with or without associated edema that occurs during the second half of pregnancy. Those with chronic hypertension may progress to preeclampsia or it may develop independently. Preeclampsia is a serious condition affecting 5% to 10% of pregnancies with signs and symptoms that include headache, visual disturbances, abdominal pain, confusion, and decreased urination. Patients with these signs and symptoms of preeclampsia or an elevated blood pressure require prompt ED evaluation. Notification prior to arrival to the receiving ED of the patient's diagnosis, signs and symptoms, or pertinent vital signs is extremely helpful.
Eclampsia involves the signs and symptoms of preeclampsia along with seizures. The seizing pregnant patient in the second trimester of pregnancy requires immediate treatment with 4 to 6 mg of magnesium over 15 minutes. Prehospital providers should notify medical control immediately for assistance in managing this complicated patient in extremis. Communication to the medical control physician should include pertinent information such as age, pregnancy status (37 weeks, etc), vital signs if attainable, and any other pertinent diagnosis (for example, an established history of preeclampsia or hypertension). Prompt transport must take place as the definitive treatment for preeclampsia and eclampsia is delivery of the fetus. Early notification to the receiving facility is essential as obstetrical consultation and emergent deliver may be required. Seizure management and administration of magnesium are immediate concerns in the prehospital environment. Management of hypertension is a secondary concern in the prehospital setting.
Vaginal bleeding during the second half of pregnancy is particularly dangerous and is associated with fetal death in one-third of cases.4 Two significant causes of late term bleeding include placenta previa and abruptio placentae.
Placenta previa occurs when the placenta implants over the cervical os and is responsible for one-fifth of bleeding episodes during the second half of pregnancy (Figure 45-1). There are three categories of placenta previa: marginal (where the placenta implants next to but not over the cervix), partial (where the placenta covers a portion of the cervix), and complete (where the placenta covers the entire cervix). Placenta previa should be suspected with the onset of painless bright red bleeding during the late second and early third trimester.
Complete placenta previa. (Reprinted with permission from Tintinalli JE, Stapczynski JS, Ma OJ, Cline DM, Cydulka RK, Meckler GD, eds. Tintinalli's Emergency Medicine: A Comprehensive Study, 7th ed. New York, NY: McGraw-Hill; 2011.)
Abruptio placentae is the early or premature separation of the placentae from the uterine wall (Figure 45-2). The phenomenon occurs in approximately 1% of pregnancies and must be considered when the patient in her second half of pregnancy complains of sudden onset of vaginal bleeding, abdominal pain, and a sense of constant contractions. Symptoms may also include dizziness, nausea, vomiting, or mild abdominal discomfort. On examination, the uterus is often firm and excessively tender. Abruptio placentae must be given significant consideration as it is one of the most serious complications of pregnancy and can be potentially devastating to mother and child. Abruptio placentae may occur with trauma, stimulant abuse, or more commonly spontaneously with hypertension being a significant risk factor. Early consideration of the condition should be undertaken and steps to address potentially significant hemorrhage should be employed. Early notification of the receiving facility is again an important step to minimize any delay in mobilizing appropriate resources.
Abruptio placentae. (Reprinted with permission from Tintinalli JE, Stapczynski JS, Ma OJ, Cline DM, Cydulka RK, Meckler GD, eds. Tintinalli's Emergency Medicine: A Comprehensive Study, 7th ed. New York, NY: McGraw-Hill; 2011.)