Prehospital Management of Obstetric Bleeding
Most pregnancies progress to term without difficulty; however, others will develop complications such as vaginal bleeding. Vaginal bleeding may occur during any stage of pregnancy and range from benign implantation bleeding to life-threatening postpartum hemorrhage. In the first trimester, vaginal bleeding may play a role in late pregnancy complications including gestational hypertension, placental abruption, low birth weight, lower APGAR scores, perinatal death, preterm delivery, prelabor rupture of membranes, and intrauterine growth restriction.1,2,3 First trimester vaginal bleeding occurs in 25% of all pregnancies, 50% of which will result in a spontaneous abortion.4 Vaginal bleeding may result from disruption of blood vessels in the uterine decidua or from discrete cervical or vaginal lesions. The clinician typically makes a provisional diagnosis based on the patient’s gestational age and the character of bleeding with the definitive diagnosis confirmed by laboratory and imaging studies.
The ability of Emergency Medical Services (EMS) to evaluate vaginal bleeding in the field is challenging as prehospital providers often have limited information. The priority for any EMS provider is to stabilize and transport these patients expeditiously according to their level of training and capabilities. Although some prehospital providers can resuscitate a patient in hemorrhagic shock, others do not have the training, certification, or licensure to perform these skills. The treatment rendered by various prehospital providers is determined by the state and/or EMS medical director as well as established treatment protocols.
There are anatomic changes that occur throughout pregnancy that impact the evaluation and management of these patients. An average weight gain of 25 to 35 pounds will occur at full term.5 Much of this weight gain is comprised of fluids (blood volume and extracellular fluids), fetus, uterus, and breast tissue. The distribution of this weight may provide the prehospital provider with challenges in airway and traumatic injury diagnosis and management.
There are physiologic changes occurring throughout pregnancy. Blood volume increases up to 1500 mL during pregnancy, with an average rise of 48% over that of a nonpregnant woman.6 The blood volume changes in pregnancy are believed to have several beneficial effects including mitigating the effects of blood loss during delivery, improving blood flow to the enlarging uterus and the delivery of nutrients to the growing fetus, and protection of the fetus from reduced venous return when the mother lies supine.7 The vital signs are dynamic in pregnancy with decreases in blood pressure early in pregnancy that normalize in later stages of pregnancy as well as progressive increases in heart rate and cardiac output. These changes impact the prehospital evaluation of blood loss due to vaginal bleeding.
Obstetric bleeding may be distressing to the patient and family and can portend substantial harm to the mother and neonate. The etiology, diagnosis, and management of vaginal bleeding in pregnancy is often divided into either the first trimester or the second and third trimester time frame.
The prehospital provider should obtain a thorough history in the evaluation of a pregnant patient complaining of vaginal bleeding, including the last menstrual period, due date, number and type of previous deliveries, description of the bleeding, presence of tissue, and complications of prior pregnancies. The patient should be asked about any abdominal pain and, if present, the type, severity, location, and frequency of the pain.
The patient’s skin, capillary refill, and mental status provide valuable information regarding her hemodynamic status. The vital signs may demonstrate signs of hypovolemia such as tachycardia and hypotension. When abnormal vital signs are present, a rapid evaluation and transport to the hospital for definitive care should occur. The physical examination includes evaluation for abdominal tenderness. A digital pelvic examination is beyond the scope of practice for prehospital providers in cases of vaginal bleeding in pregnancy and should be avoided.
The differential diagnosis of first trimester bleeding includes ectopic pregnancy, threatened abortion, inevitable abortion, complete abortion, incomplete abortion, missed abortion, vaginitis, trauma, tumor, warts, polyps, fibroids, ectropion, and implantation bleeding. The differential diagnosis of second and third trimester vaginal bleeding includes spontaneous abortion, uterine rupture, placenta previa, placental abruption, bloody show associated with labor, and vasa previa. In many EMS systems, point of care ultrasound is becoming common and use in the evaluation of pregnancy continues to evolve and may be helpful as a diagnostic aid.
The prehospital management of vaginal bleeding in pregnancy is guided by the signs and symptoms identified in the history and physical examination as well as by the type of EMS provider and established treatment protocols. The protocols implemented by the EMS medical director provide guidance on appropriate patient management.
In hypotensive pregnant patients, advanced emergency medical technicians (AEMTs) and paramedics should start two large-bore intravenous (IV) lines and initiate IV fluids as recommended by prehospital protocols. Although there continues to be discussion on the optimal IV fluids to use in critically ill patients, the prehospital provider should follow agency guidelines.10 In some EMS systems, blood products may be administered by paramedics according to established protocols to correct hypovolemia secondary to blood loss.11,12,13,14 In patients with brisk and/or uncontrolled bleeding, tranexamic acid (TXA) may also be considered by the prehospital providers if permitted under their protocols. Studies show promise with TXA use in postpartum hemorrhage.15,31
Analgesics may be administered with consideration of vital signs and according to protocols, especially if the patient is hypoxic or hypotensive. In most systems, IV medications are limited to the paramedic prehospital provider. To supplement traditional narcotic medications, some EMS systems use IV acetaminophen, ketorolac, or even sub-dissociative doses of ketamine for analgesia; however, ketamine and ketorolac are contraindicated in pregnancy.16,17 In patients with signs of tachycardia, hypotension, or evidence of hypovolemic shock, rapid evaluation and transport for definitive care at a hospital should occur. A cardiac monitor and frequent vital sign measurements (every 5 minutes) are recommended in the acutely ill patient.
FIRST TRIMESTER VAGINAL BLEEDING
An ectopic pregnancy is when the fertilized ovum implants outside of the uterus and occurs in 1.5% to 2.6% of all pregnancies.18,19,20 The risk factors are multifactorial, and up to 50% of the women have no known risk factors.21 Risk factors associated with ectopic pregnancy include pelvic inflammatory disease, tubal surgery, previous ectopic pregnancy, cigarette smoking, age greater than 35 years, and multiple sexual partners.
The history may include referred pain to the shoulder indicating irritation to the diaphragm from intraperitoneal blood (Kehr’s sign) in cases of ruptured ectopic pregnancies. Less than half of ectopic pregnancies have the classic presentation of abdominal pain, vaginal bleeding, and delayed menses.22 The physical examination should determine the location and severity of abdominal tenderness as well as vital signs and physical findings concerning for hemorrhagic shock. The management of ectopic pregnancy by prehospital providers is dictated by the signs and symptoms, category of prehospital provider, and treatment protocols (Table 10.1).