Chapter 41: Obstetrics

What changes occur during pregnancy that affect medication metabolism?

1. As was mentioned previously, venous pressures increase in the lower extremities late in pregnancy, meaning that subcutaneous and IM medications will be absorbed more slowly. 2. Hepatic metabolism increases, so higher medication doses may be required. 3. Renal excretion increases so medications may not stay in the maternal system as long as they normally might. 4. Gastric absorption is slowed so oral drugs may take longer than usual to achieve their desired effect.

How should postpartum hemorrhage be managed in the field?

1. Continue with your uterine massage. 2. Encourage the woman to breastfeed (which stimulates oxytocin production). 3. Administer oxytocin. 4. Notify the receiving facility of the patient's status and ETA. 5. Transport without delay. 6. Start a 2nd large-bore IV and administer normal saline wide-open. 7. Do not attempt an internal examination of the vagina. 8. Do not attempt to pack the vagina with any dressings. 9. Manage any external bleeding from peritoneal tears with firm pressure and ice packs.

How should a pregnant female involved in a trauma be managed in the field?

1. Ensure an adequate airway. Because these women are prone to aspiration, provide early intubation if unconscious. Provide cricoid pressure until the airway is secured. 2. Administer high-flow oxygen via NRB. Remember that a pregnant female's oxygen demand is 10 - 20% greater than normal, and the fetus will become hypoxic before the mother will. 3. Assist ventilations as needed and at a higher than normal rate. You will likely have more difficulty than usual - especially pre-intubation - due to the diaphragm being pushed upward. 4. Control any external bleeding and splint any fractures. 5. Start 1 - 2 lines of normal saline. Administer a bolus for any signs of hemodynamic compromise with the goal of maintaining her blood pressure, and remember that a larger volume of fluid is needed for a pregnant female. 6. Notify the receiving facility of the patient's status and ETA. 7. Transport left-lateral recumbent to prevent supine hypotensive syndrome. If backboarded, tilt the board 30° by wedging pillows beneath it.

What unique questions need to be asked to a pregnant patient during the history-taking portion of the assessment?

1. How many times she's been pregnant (gravida) and how many births she's had (para)? 2. Has she experienced any complications with any of her pregnancies, or has she had any obstetric or gynecologic complications? 3. Has the patient ever had a cesarean section and, if so, does she intend for this delivery to be cesarean? (Complications of vaginal birth after cesarean section include uterine rupture.) 4. Is the patient currently under a physician's care? If so, when was her last visit and did the obstetrician indicate any concerns about this pregnancy? 5. Has she been taking prenatal vitamins? 6. Has the patient had a recent ultrasound? If so, what were the findings, and did it indicate more than one fetus or an abnormal position? 7. Is the patient taking any medications or using any OTC meds, recreational drugs, or herbal supplements? 8. Has she smoked, consumed any alcohol, or used any illicit drugs during the pregnancy? Is yes, how recently? 9. Has the patient noticed any vaginal bleeding or spotting? If so, how much bleeding and how long did it last? What color was the blood - red or brown? What was she doing prior to the bleeding? Has the bleeding stopped and has she passed any clots? 10. Has she had any other vaginal discharge? If so, what was the amount, color and duration? Was there any odor associated with the discharge? 11. If the patient is in active labor, has her water broke? Does she feel the need to move her bowels or push? (The urge to move her bowels may be caused by the fetus' head pushing against the rectum and should not be allowed. Shitting babies into toilets is frowned upon.) 12. If applicable, how frequent are the contractions and how long do they last? 13. If applicable, when was the last time she felt the fetus move and have there been any changes in how much the fetus has been moving?

What functions does the placenta perform during the pregnancy?

1. It serves as an early liver. 2. It synthesizes glycogen and cholesterol. 3. It metabolizes fatty acids. 4. It produces antibodies to protect the fetus. 5. It functions as the fetal lungs, enabling the fetus to exchange its carbon dioxide-laden blood for oxygen-rich blood. 6. It allows for the transport of nutrients from maternal to fetal circulation. 7. It facilitates the excretion of waste, some of which goes into the mother's circulation and some of which is excreted into amniotic fluid. 8. It allows for the transfer of heat from the mother to the fetus. 9. Approx. 10 - 12 weeks into the pregnancy, it begins producing human chorionic gonadotropin (hCG) which maintains the pregnancy and stimulates changes in the women's breasts (awesome), vagina (not awesome), and cervix that prepare her for delivery and motherhood. 10. It forms a barrier against harmful substances in the pregnant woman's circulation, such as chemicals and microorganisms.

What physiologic maternal changes occur during pregnancy. When applicable, what significant does this hold to emergency medicine?

1. The most notable change occurs in the uterus which increases in size and weight. The increased weight places pressure on the lower end of the intestine and the women's rectum which often results in constipation. The smooth muscles of the GI tract additional have decreased motility due to the increased progesterone, sometimes resulting in heartburn and burping. Because the stomach is not being emptied as quickly, pregnant women are at an increased risk of vomiting during an emergency, potentially resulting in airway compromise. 2. The kidneys increase in volume by as much as 30% and the ureters increase in diameter (the right more so than the left). This, coupled by increasing pressure placed on the urinary bladder by the enlarging uterus, results in increased urinary frequency and an associated increased risk of UTI. 3. Increased hair and nail growth, and a change in texture, are common in women during pregnancy. Some women develop a "pregnancy mask": brown and yellow color changes around the eyes, cheeks, and nose. The skin may additionally darken around the areola, axilla, and genitalia. A dark line of pigment down the middle of the abdomen, called the linea nigra, also develops in many women. 4. Blood volume increases by 30 - 50% as compared to pre-pregnancy levels, increasing rapidly over the first half of pregnancy and then stabilizing by term. At term, the uterus contains ~15% of the woman's total circulating blood. Approximately 500 mL (in vaginal delivery) and up to 1000 mL (in cesarean section) of blood are lost during birth. 5. As blood volume increases, RBC count increases by ~33%. This is why pregnant women often take prenatal supplements. If the women does not have enough iron, anemia can lead to preterm labor and spontaneous abortion. 6. WBC count as well as levels of clotting factors and fibrinogen increase. These issues are important considerations if you're dealing with an obstetric hemorrhage or thromboembolic disease. 7. The size of the woman's heart increases (#aww). Due to the increased cardiac workload, cardiac output increases by 30 - 50% by about 22 weeks' gestation, and then declines to about 20% by term. The heart is additionally displaced upward, forward, and to the left by the diaphragm being pushed upward. This causes the heart to be displaced laterally which is significant for auscultation. Lastly, of note, S-1 heart sounds increase while S-2 sounds remain the same, and murmurs are not uncommon. Note that while the increased workload is insignificant in healthy individuals, women with heart disease or other forms of cardiac compromise are at risk of heart failure and pulmonary edema. 8. Heart rate increases by an average of 15 - 20 bpm by term, and ectopic beats and SVT are often considered normal during pregnancy. With that, common ECG changes include: a slight left-axis deviation and Lead III changes such as a low-voltage QRS, T-wave inversion or flattening, and even occasional Q-waves. 9. As the pregnancy progresses, the woman becomes increasingly sensitive to body positioning. After 20 weeks' gestation, lying supine can cause the uterus to compress the inferior vena cava and common iliac vein, resulting in a drop in cardiac output, hypotension, and edema in the lower extremities. Systolic and diastolic blood pressures naturally decrease until ~24 weeks' gestation, at which point they increase until birth and then normalize thereafter. 10. Late in pregnancy, venous pressures increase in the lower extremities. The enlarged uterus slows venous return, increasing the woman's risk of dependent edema, hemorrhoids, and varicose veins in the legs. Additionally, she is at an increased risk of DVT formation, especially if bedridden. This decreased venous return means that subcutaneous and IM medications will be absorbed more slowly, so be mindful of this when administering medications. 11. The uterus displaces the diaphragm upward which results in the rib margins flaring outward so as to allow for the woman to maintain intrathoracic volume. The abdominal muscles additionally loose their tone throughout pregnancy, allowing for more diaphragmatic breathing. The result of the diaphragm being displaced, however, is a decrease in expiratory reserve volume, functional residual capacity, and residual volume. Tidal volume and inspiratory reserve volume increase (as mentioned below), and respiratory mucus membranes increase in vascularity and edema. 12. Maternal oxygen demand increases, and as such oxygen consumption increases by 20 - 40%. Biochemically, this is accomplished by progesterone acting on the medulla to decrease its threshold for CO2. It also causes the bronchi to dilate and regulates mucus production causing a decrease in airway resistance. The effect is an increase in tidal volume of 30 - 50% by 8 weeks' gestation. This causes minute ventilations to increase by as much as 50% and for PaCO2 values to drop by ~5 mmHg. This respiratory alkalosis is balanced by metabolic acidosis, with a particularly marked imbalance during labor which returns to normal ~3 weeks postpartum. 13. The maternal metabolism undergoes obvious changes with the average woman gaining 27 pounds during pregnancy. This is due, in part, to increased blood volume, intra- and extracellular fluids, uterine growth, placental growth, fetal growth, breast tissue, and an increase in protein and fat deposits. 14. Relaxin is released during pregnancy which causes collagen to soften and produces a general relaxation of the ligamentous system, especially along the spine. Increased joint laxity is manifested particularly by increased lordosis and pubic symphyseal laxity. 15. Pregnancy increases a woman's demand for carbohydrates as the fetus is dependent on glucose. Free cortisol and progesterone cause insulin to be secreted by the pancreas in greater amounts and at a faster pace, while estrogen blunts its effects and progesterone decreases its utilization by the mother, thereby freeing it up for the fetus. Obese women and women predisposed to diabetes have a difficult time balancing this and it's not uncommon for women to develop chemical diabetes during pregnancy which normalizes after delivery.

How long is the human gestational period? How can it be calculated?

38 weeks. The due date can be calculated by identifying the first day of the last menstrual cycle, adding 1 year, subtracting 3 months, and adding 7 days. Because the placental tissue usually starts sending hormonal signals to the corpus luteum to start changing the internal environment in the second week after conception, this dating method adds two weeks to the entire calculation, leading to 40 total weeks from conception to birth.

How frequent are contractions suggestive of an imminent delivery?

< 2 minutes apart and regularly spaced. If they are > 5 minutes apart, you typically have time to get her to the hospital.

What is a prolapsed umbilical cord and how should it be managed in the field?

A condition in which the cord emerges from the uterus ahead of the fetus. With each contraction, the cord is thus further compressed between the presenting part and the pelvis. This occurs in ~10% of deliveries. This cannot be delivered in the field. You should: 1. Position the mother supine with her hips elevated as much as possible with pillows. Administer 100% oxygen via NRB. 2. Instruct the mother to pant with each contraction (it closes the glottis and keeps her from contracting). 3. With two fingers, push the presenting part (not the cord) back into the vagina until it is no longer pressing on the cord. 4. While you maintain pressure on the presenting part, have your partner cover the exposed cord with dressings moistened in warm saline. 5. Try to maintain that position keeping the body part off the cord and transport rapidly to the hospital.

What is cephalopelvic disproportion and how is it typically managed?

A condition in which the head is larger than the pelvis, resulting in possible massive hemorrhage upon delivery and other complications. Typically mothers know they have this if they've been following up with their OB and you should ask about it before attempting to deliver in the field.

What is hydramnios? What risk factors predispose one to the condition and what complications can it present?

A condition in which there is too much amniotic fluid (recall that most pregnancies have ~500 mL). Risk factors include multiple gestation, fetal anemia, diabetes in the mother, and fetal conditions that cause it to stop swallowing the fluid. This is usually detected by ultrasound in advance, as it leads to an increased risk of prolapsed cord and abruptio placenta (due to the increased size of the uterus), and postpartum hemorrhage (an overstretched uterus may not contract as well).

What is shoulder dystocia and how should it be managed in the field?

A difficulty in delivering the shoulders. It occurs after the head delivers and the shoulders cannot get passed the mother's symphysis pubis. It poses a fatal risk to the fetus who's at risk of cord compression, as well as possible damage to his brachial nerve plexus. The safest technique for managing this is the McRoberts maneuver: To widen the woman's pelvis and flatten the lower back, hyperflex her legs tightly to her abdomen. It may be necessary to apply suprapubic pressure (on her lower abdomen) and to gently pull on the fetus' head.

What is the amniotic sac? How much fluid can it hold? What functions does it serve?

A membranous bag that encloses the fetus in a watery substance called amniotic fluid. The volume can reach 500 - 1000 mL and constantly fluctuates throughout the pregnancy. The fluid provides a weightless environment for fetal growth. In the latter stages of pregnancy, the fetus swallows amniotic fluid and passes waste back out into the fluid. In this way, it assists in fetal excretory function.

How is a post-term pregnancy defined and what risks are associated with it?

A pregnancy that lasts > 42 weeks' gestation. The cause is often unknown, and risk factors include previous post-term pregnancies and irregular menstrual cycles that increases the chances of a miscalculation of due date (that's not actually post-term then but ok, Nancy Caroline). The pregnancy is considered high-risk because of the risk of malnourishment from placental dysfunction as well as meconium aspiration. Because the fetus is now larger, deliveries are often complicated and long, and generally physicians elect for cesarean section.

What is abruptio placenta and how does it present?

A premature partial or incomplete separation of a normally implanted placenta from the wall of the uterus. It most commonly occurs in the 3rd trimester and presents as a sudden onset of severe abdominal pain, often radiating into the back. There will be decreased fetal movement and fetal heart tones. The patient may report vaginal bleeding, although it may also be concealed within the endometrium. Physical exam may reveal signs of shock, often out of proportion to the apparent volume of blood loss. The abdomen will be tender and the uterus rigid. The biggest potential complication is hemorrhage, and if it cannot be controlled after delivery a hysterectomy will be performed.

When should a pulmonary embolism be suspected around childbirth?

A pulmonary embolism may arise from an amniotic embolism, a DVT, or a water embolism in cases of water birth. They should be suspected whenever a woman experiences sudden dyspnea, tachycardia, a-fib, or hypotension in the peripartum state. The patient may report sudden, sharp chest or abdominal pain, and may experience syncope. Be careful not to mistake it as shock and manage it as you would any normal pulmonary embolism: recognition, high-flow oxygen, and rapid transport.

What is uterine inversion? How does it occur and how should it be managed in the field?

A rare but potentially fatal complication of childbirth in which the placenta fails to fully detach from the uterine wall when it is expelled, and the uterus literally gets pulled inside out. It typically occurs as a result of mismanaging the 3rd stage of labor, either due to placing excessive pressure on the uterus while performing a fundal massage or from pulling on the umbilical cord. The prolapse can be incomplete or complete, with a complete inversion protruding from the vagina. This condition is very painful and hypovolemic shock may develop rapidly. It should be managed as follows: 1. Keep the patient recumbent. Administer 100% oxygen via NRB. 2. Start two IVs and titrate normal saline to the mother's blood pressure. 3. if the placenta is still attached to the uterus, do not attempt to remove it. Carefully monitor vitals and treat for shock. 4. Consider giving oxytocin to help control exsanguinating hemorrhage if allowed by local protocol. 5. You can make one attempt to replace the uterus. Push the uterus fundus-up through the vaginal canal by applying pressure with the fingertips and the palm of your gloved hand. If this fails, cover all protruding tissue with a moist sterile dressing and transport rapidly.

What kidney issues may occur during pregnancy?

A woman's kidneys increase in length and her ureters become longer, wider, and more curved. This may lead to urinary stasis which increases the chances of UTI. Additionally, pressure placed on the bladder by the growing fetus increases urinary frequency. As the renal plasma flow rate and glomerular filtration rate increases, the stress placed on the kidneys - either new in onset or as an exacerbation of a preexisting condition - may lead to kidney failure.

Define the following related terms: abortion, spontaneous abortion, elective abortion, habitual abortions, threatening abortion, imminent abortion, incomplete abortion, complete abortion, missed abortion, and septic abortion. Advise how EMS should manage the patient as applicable.

Abortion: The expulsion of the fetus, from any cause, before the 20th week of gestation. Spontaneous abortion: Commonly referred to as a miscarriage, in these instances the abortion happens naturally. It's fairly common and is estimated to occur in 10 - 25% of all pregnancies. Common causes include acute and chronic illness, exposure to toxic substances (i.e. illicit drug use), abnormalities in the fetus, or abnormal attachment of the placenta. In many cases, the cause remains unknown. Elective abortion: An abortion brought about intentionally. Habitual abortions: 3 or more consecutive pregnancies that end in abortion. This is seen in < 1% of the population and is correlated to chromosomal and endocrine disorders, ovarian issues, uterine malformations, cervical conditions, infections, and lifestyle factors. Threatened abortion: An abortion that is attempting to take place. It is typically characterized by vaginal bleeding during the first half of the pregnancy - usually the first trimester. The patient may present with abdominal pain and report menstrual cramps. The patient is not usually in severe pain, as uterine contractions are not rhythmic. The cervix remains closed. This may progress to an incomplete abortion or it may subside and progress to term. The only treatment is bedrest, ideally in a hospital where the mother can be monitored. Imminent abortion: A spontaneous abortion that cannot be prevented. Vaginal bleeding, often massive, will be present, and the cervix will be dilated as the uterus attempts to expel its products. Your goal is to maintain her blood pressure and prevent hypovolemia. Establish an IV and administer normal saline to maintain blood pressure, administer 15 LPM oxygen via NRB, obtain an ECG, provide emotional support, and transport rapidly to a hospital while remaining alert for signs of shock. Incomplete abortion: Occurs when part of the products of conception are expelled but some remain in the uterus. Vaginal bleeding will be present, as the cervix is dilated. Be alert for signs and symptoms of shock, establish an IV, and administer normal saline. Consult medical direction if the products of conception are protruding from the vagina, as their removal may alleviate signs of shock. Following delivery of the fetus, a fundal massage may be beneficial in stimulating the delivery of the placenta. Be sure to collect all products of conception and bring them with to the hospital. Complete abortion: Occurs when all products of conception have been expelled. Missed abortion: Occurs when the fetus dies during the first 20 weeks of gestation but remains in utero. Management will consist of a dilation and curettage (D&C) in the hospital. The typical history will be a cessation of vaginal bleeding followed by a gradual diminishment of the signs of abortion (uterine and breast size). The woman may report having a brown, rank-smelling discharge. The uterus may feel like a hard mass and fetal heart sounds will not be present. Septic abortion: Sepsis that occurs following an abortion. The woman will typically report a fever and bad-smelling vaginal discharge in the hours following the abortion, and a physical exam will likely reveal fever and abdominal tenderness. It's caused by often normal vaginal bacterial flora entering the uterus and causing infection.

What is fetal macrosomia, what risk factors predispose one to it, and how should it be managed in the field?

Also known as "big baby syndrome," it's defined as fetus weighing more than 4500 grams (~9 lbs). Risk factors include gestational or poorly controlled diabetes, excessive weight gain, a male fetus, a large number of pregnancies, obesity, and some fetal genetic conditions. Birthing should ideally occur in the hospital due to the anatomic complications and the likely election for cesarian section. If she does birth in the field, be sure to check the baby's blood sugar as there's an increased risk of hypoglycemia.

What are Braxton-Hicks contractions? How can you differentiate between them and real contractions?

Also known as "false labor," they're contractions that can occur every 10 - 20 minutes in the 3rd trimester of pregnancy. 5 signs are: 1. Irregularly spaced contractions. 2. Contractions that do not gradually shorten. 3. Contractions that do not worsen in intensity. 4. Contraction pain that is alleviated with analgesics. 5. No change in cervical diameter.

What is an episiotomy? Given that this cannot be performed in the field, what should you do instead?

An incision made in the perineal skin to prevent the perineum from tearing during delivery (in instances needed). In the prehospital setting, you are limited to providing gentle pressure against the newborn's head to prevent an explosive birth and to give the tissues time to expand.

What is toxoplasmosis and how does it occur? What factors affect transmission of the disease and how does the disease present?

An infection caused by a parasite that pregnant women may get from eating contaminated food or exposure from handling cat litter (cats ingest contaminated food and then pass it out in their feces). For this reason, women are encouraged not to change cat litter boxes and to only eat thoroughly-cooked foods during pregnancy. Women often do not know they have the infection, and newborns often are asymptomatic but may develop learning, visual, and hearing disabilities as they grow older.

What is peripartum cardiomyopathy (PPCM), what risk factors predispose a woman to it, and how is it diagnosed?

An uncommon form of heart failure that occurs during the last month of pregnancy or up to 5 months postpartum (sometimes known as postpartum cardiomyopathy). Risk factors include: obesity, history of cardiac disorders, use of certain medications, smoking, alcoholism, multiple pregnancies, African American descent, and poor nourishment. PPCM can be easily confused with eclampsia as the two present quite similarly. The only way to differentiate between them is to rule out eclampsia by testing for proteinuria (which obviously cannot be done prehospital).

What risk does asthma pose to a pregnant woman?

Asthma can be aggravated as a preexisting condition or can occur for the first time during pregnancy, triggered by the effects of stress and respiratory irritants on an already-sensitized respiratory system. Maternal complications include: premature labor, preeclampsia, respiratory failure, vaginal hemorrhage, and eclampsia. Likewise, fetal complications may include: premature birth, low birth weight, growth retardation, and potentially fetal death.

How does fetal circulation and cardiac anatomy differ from that of an adult?

Because the fetus receives oxygenated blood from the mother, the umbilical *vein* carries oxygenated blood from the placenta to the fetus, while the umbilical *arteries* carry arteriovenous blood back to the mother. Additionally, because the fetus doesn't use its lungs, fetal circulation bypasses them entirely. To this end, the ductus venosus connects the umbilical vein and the inferior vena cava, the ductus arteriosus connects the pulmonary artery and the aorta, and an opening known as the foramen ovale separates the right and left atria of the heart. At birth, the neonate's lungs begin to function and the arteriovenous shunts close.

What is cytomegalovirus (CMV)? How does it present and what risk does it pose to pregnant women?

CMV is a member of the herpesvirus family. An estimated 80% of the US population has been exposed to it and it can lay dormant in the body for years. In its active stages, it can produce high fever, chills, headache, malaise, extreme fatigue, and an enlarged spleen. Patients with immune disorders, those receiving chemotherapy, and pregnant women are more at risk of developing the active infection, and newborns who acquire CMV are susceptible to lung problems, blood problems, liver problems, swollen glands, rash, and poor weight gain.

What is calcium chloride's role in managing eclampsia? What is the dose administered?

Calcium and magnesium are antagonists of each other and its role in the field is typically limited to hypocalcemia. That being said, it can be administered if respiratory depression develops following magnesium sulfate administration for eclampsia. The dose if 500 - 1000 mg IVP and may be repeated in 10 minute intervals. Just be aware that side-effects include: nausea, vomiting, syncope, bradycardia, dysrhythmia, and cardiac arrest.

What is cholestasis, how is it manifested, and what risk does it pose to the mother and fetus?

Cholestasis is a disease of the liver that occurs during pregnancy. Hormones slow the flow of bile from the liver to the gallbladder which can result in bile acid buildup in the liver which spills into the bloodstream. The most common symptom is profuse, painful itching, particularly of the hands and feet. Fatigue, depression, RUQ abdominal pain, and nausea are common as well. Dark urine and abnormally light-colored stools are possible. Women who are carrying multiple fetuses, as well as those with a history of liver failure and a family history of cholestasis, are at an increased risk of the condition. This is relatively benign for the mother but can be life-threatening for the fetus which relies on the mother's liver to remove bile acids from its blood. As such, preterm births and stillbirths are potential complications of untreated cholestasis.

What is hyperemesis gravidarum? What predisposes a woman to this? How do these women present and how should they be managed in the field?

Commonly known as "morning sickness," it's a condition of persistent nausea and vomiting during pregnancy, especially during the first several weeks. If prolonged, vomiting may lead to dehydration and malnutrition. The exact cause is unknown, but it's suspected to be related to the increased estrogen and hCG levels, stress, and GI changes. It's most common in first-time pregnancies, pregnancies with multiple gestations, and in obese women. Symptoms include: severe and persistent vomiting more than 3 - 4 times per day, severe nausea, pallor, and possibly jaundice. Additionally, the vomiting is typically projectile and may contain bile and blood. Management includes: 1. Check the patient's blood sugar. 2. Start an IV, administer 250 mL normal saline, and reassess. 3. Administer 25 - 50 mg diphenhydramine IV or deep IM, if allowed by protocol. It has both sedative and antiemetic effects which are of benefit. 4. Administer 4 mg ondansetron IV or PO, as allowed by protocol. (Per the appendix, it may be repeated once after 10 minutes as needed.) 5. Check orthostatic vital signs and obtain a 12-lead ECG. 6. Transport. Severe cases will require hospitalization.

How should the placenta look? What should be done with it?

One side (the fetal side) will be gray, shinny, and smooth. The other (the maternal side) will be dark maroon and rough in texture. It should be placed in the plastic bag in the OB kit and brought with to the hospital.

What is the best indication of the status of the fetus after trauma?

Fetal heart rate, which should be between 120 - 160 bpm. A rate < 120 indicates fetal distress.

What is gestational hypertension and what is the diagnostic criteria? What risk does this pose to the patient?

Formerly known as pregnancy-induced hypertension, it's hypertension that develops after the 20th week of pregnancy in women with previously normal blood pressures that return to normal postpartum. It is more commonly experienced by women who are obese or glucose intolerant, and may be an early sign of preeclampsia.

What is gravidity and parity, respectively?

Gravidity: Total number of times a woman has been pregnant, regardless of births. (It comes from the Latin word "gravis" meaning heavy. Think gravity.) Parity: Total number of live births.

What abdominal changes occur during pregnancy that affect trauma?

Her abdominal contents are compressed into the upper abdomen, so there is a higher incidence of abdominal injuries associated with chest trauma. Additionally, the bladder gets displaced upward and forward and is at increased risk of trauma. During the 2nd and 3rd trimesters, the uterus effectively shields the woman's abdominal organs. So pregnant women with penetrating abdominal trauma actually have better outcomes, although there is often fetal injury. Lastly, be mindful of fetal injury if a woman in an MVC is found to have placed her lap belt above her uterine dome. Also note that blood volume is redistributed throughout her body, with a roughly tenfold increase in blood flow to her pelvis. Thus, in instances of pelvic fracture, be mindful of the increased risk of hemorrhage.

How should acute diabetic episodes be managed during pregnancy?

Hypo- and hyperglycemic events will present the same way they would in a normal patient and should be managed just the same. Just be aware that in addition to gestational diabetes which is new in onset during the pregnancy, pregnant women with a history of diabetes are more prone to having episodes due to the fluctuating hormonal changes. Lastly, in a seizing pregnant patient, don't get so caught up in the thought of eclampsia that you forget to check a sugar.

If you end up delivering breech in the field, how should the delivery be managed?

Ideally, you want a woman who knows she'll be delivering breech to do so in the hospital. If this is not possible: 1. Position the mother with her buttocks at the head of the bed or stretcher and her legs flexed. Allow the buttocks and trunk to deliver spontaneously. One the legs are clear, support the body and lower him so that he nearly hangs to help with the head delivery. 2. When you can see the hairline, grasp the newborn by the ankles and lift him upward in the direction of the mother's abdomen. The head should then deliver without difficulty. 3. If the newborn's head does not deliver within 3 minutes, he is at risk of suffocation. Place your gloved hand in the vagina with your palm facing the newborn's face. Form a V with your fingers on either side of the baby's nose and push the vaginal wall away from the face until he's delivered. 4. Do not attempt to pull the newborn out. If delivery does not occur within 3 minutes of managing the airway, transport emergently.

Under what circumstances should a woman in labor be transported emergently to the hospital rather than delivering on scene?

If (a) delivery does not occur within 30 minutes or (b) you determine that a complication is occurring that cannot be managed in the field.

How should ventilations be managed differently in a pregnant patient?

In general, a respiratory rate < 20 breaths/minute is considered inadequate in a pregnant patient who sustains a trauma. If she requires artificial ventilation, do so at a higher minute volume than normal.

What occurs during the first stage of labor? How long does it last.

It begins with the onset of labor pains - crampy abdominal pain that may radiate into the small of the back. These early contractions occur in 5 - 15 minute intervals and they serve to maneuver the fetus into position. This stage can be subdivided into phases: Latent phase: Begins when the cervix begins to dilate and efface. Effacement is the thinning and shortening of the cervix which is accomplished by progressive cervical dilation. Active phase: There is a noticeable increase in the intensity of contractions which occur more regularly, last longer, and are closer together. Cervical dilation occurs to about 7 cm. Transition phase: This begins when the cervix is dilated to 10 cm, during which the woman may feel an urge to bear down or have a bowel movement. Toward the end of this phase, the amniotic sac often ruptures with a gush of fluid pouring out of the vagina. This first stage lasts an average of 8 - 12 hours in a nulliparous woman and 6 - 8 hours in a multiparous woman.

What is the function of the umbilical cord?

It connects the placenta to the fetus via the fetal umbilicus (the naval).

What is terbutaline? What is its indication with regard to pregnant patients? What is the dose administered?

It is a tocolytic and sympathetic agonist that can be used to suppress preterm labor by causing uterine relaxation. It is indicated for cord prolapse which cannot be delivered in the field, and can also be used to treat pregnancy-induced asthma because of its bronchodilator effects. Its dose is 0.25 mg subcutaneous which may be repeated in 15 - 30 minutes for a maximum dose of 0.5 mg every 4 hours.

How common is postpartum depression and what risk factors are associated with it?

It occurs in 1/9 women. Risk factors include: adolescent mothers, a previous or family history of depression, financial or marital/relationship issues, diabetes, a complicated delivery or pregnancy, major life-changing events (job loss, divorce, death of a loved one, etc), infertility issues, and multiple gestation. Strongly advocate for transport for these women so that they may obtain the psychological care they need.

What is "premature rupture of the membranes." What is the risk associated with it?

It refers to the premature rupture of the amniotic sac. In some instances the sac will heal itself. More commonly, labor will be induced within 48 hours. There's little concern if the fetus is near term, but if the fetus is premature there is risk of infection. Provide emotional support and transport to the hospital.

If the delivery of the baby is imminent and you do not have time to place the sterile drapes, what should you do?

Just concentrate on controlling the delivery. A safe and controlled delivery takes precedence over draping procedures.

How should vaginal hemorrhage in a pregnant female be managed in the field?

Keep the patient left-lateral recumbent and administer 15 LPM oxygen via NRB. Provide rapid transport to a definitive care facility. Start a large-bore IV and administer 250 mL boluses of normal saline, reevaluating each time, for a blood pressure of 90 mmHg systolic; if you reach your 20 mg/kg max and the patient's blood pressure is < 90 mmHg, contact medical control. Obtain an ECG and obtain baseline vitals. Do not attempt to examine the woman internally and do not pack the vagina. Rather, loosely place trauma pads over the vagina in an effort to stop the flow of blood.

What is considered preterm labor? How is it treated?

Labor that begins after the 20th week but before the 37th week of gestation. If the patient is not near term, her physician will likely admit her for bedrest, medication, and monitoring.

How does magnesium sulfate work to stop seizures. What is the dose administered for seizure activity associated with pregnancy?

Magnesium sulfate is an NMDA receptor antagonist, thereby functioning as a CNS depressant. (Of note, there is a particularly high concentration of NMDA receptors in the hippocampus.) 1 - 4 g of a 10% solution should be administered IV/IO over 3 minutes with a maximum dose of 30 - 40 g/day. It must be administered slowly, as it can cause respiratory depression, hypotension, and potentially circulatory collapse. Alternatively, 10 mg can be administered IM (note that it states this in the text but not in the back of the book), and in such instances the total dose should be split between two syringes and injected into two different locations.

What physiologic changes are commonly seen in women and fetuses, respectively, during labor?

Mother: Blood pressure, heart rate, cardiac output, and respiratory rate all increase. Of note, blood pressure can increase 15 points during contractions, so taking blood pressures during contractions gives false readings. WBC production increases in response to stress, and the renal system preserves fluids and electrolytes. Diaphoresis is common in response to an increase in CBT, and blood flow is shunted away from the GI tract resulting in potential nausea, vomiting, and diarrhea. Fetus: Blood flow is reduced to the fetus during contractions and a decreased fetal heart rate occurs during this time. The bouts of hypoxia and the buildup of lactic acid lead to a degree of fetal acidosis. Conditions that can worsen this acid-base imbalance are: nuchal cord, multiple births, abnormal fetal position, respiratory conditions, shoulder dystocia, and other complications of childbirth.

What changes apply to performing CPR on a pregnant female?

Normal ACLS care should be provided with one caveat. Rather than keeping the patient left-lateral, she should be placed supine and another rescuer should manually displace the uterine leftward, thereby alleviating any pressure on the inferior vena cava. Additionally, since landmarks may be harder to find, use the sternal notch as a guide for hand placement. Lastly, CPR and transport should still be initiated on an obviously dead (i.e. decapitated) female, as an emergency cesarean section can still be attempted in the ED.

What postpartum care should be performed with regard to the mother?

Obtain vital signs and monitor closely for postpartum hemorrhage and shock, seizure activity, or respiratory difficulty. Assess the fundus which should be palpable around the umbilicus. Massaging it after placental delivery will help to control postpartum hemorrhage. Determine whether the lochia (the postpartum discharge) appears as expected (red in the first few days, and increasingly brown for the several weeks postpartum). Lastly, cover the mother with a blanket to prevent mild hypothermia.

What is nuchal cord? How should it be managed?

Occurring in 15 - 34% of all births, the umbilical cord may become wrapped around the baby's neck during fetal descent. It rarely results in death, but is one of the first things you should look for after his head emerges. If you find the cord wrapped around the neck, try to slip if off. If you can't, place umbilical clamps 2" apart and cut the cord (going away from the infant).

What are the premonitory signs of labor?

Often going unnoticed, the first sign is lightening: a relief of pressure felt in the woman's upper abdomen and a simultaneous increase in pressure in her pelvis as the fetus starts its descent toward the birth canal. Additionally, as the cervix begins dilating, a plug of mucus sometimes mixed with blood (referred to as bloody show) is expelled from the vagina. Of note though, this latter step can occur weeks before labor.

How long is labor in first-time mother?

On average, 16 hours.

When should oxytocin be administered in the context of pregnancy? What is the dose administered?

Oxytocin is a naturally occurring hormone that triggers uterine contractions by acting on smooth muscle. It can be used to induce labor but is commonly used to control postpartum hemorrhage. In the prehospital setting, it should only be used to manage severe postpartum bleeding and only after all products of conception have been expelled from the uterus. Its dose is 10 units IM. If given IV, mix 10 - 40 units in 1000 mL of non-hydrating dilutent and infuse at 20 - 40 milliunits/minute titrating to the severity of bleeding and uterine response.

What women are most at risk of uterine rupture? How does it present and how should it be managed in the field?

Patients at greatest risk are those who have had many children and those with a uterine scar (such as from a previous cesarean section). These patients are often in labor reporting weakness, dizziness and thirst. She will likely report contractions that came on very strongly and painfully but then slackened off, and now reports a sharp, tearing pain. She may show signs of shock - sweating, tachycardia, and falling blood pressure - and may or may not have significant vaginal bleeding. Treat for shock and transport rapidly.

What complications may arise following the delivery of a baby with a mother who used illicit drugs during the pregnancy?

Since the drugs often pass through the placenta, the baby may effectively be a drug addict as well. This means that the newborn may have signs of withdrawal after it is born - for example, respiratory depression, bradycardia, tachycardia, seizures, and cardiac arrest. Management revolves around cardiorespiratory support.

What is the correlation between risk of vaginal bleeding and length of pregnancy?

Positive. As the mother nears term, the risk of complication increases. A pregnant woman near term can lose a full 40% of her circulating volume before signs and symptoms become apparent. (Recall from Trauma that 40% blood loss in a normal individual would lead to irreversible shock.)

What is preeclampsia and what are its classic triad of signs? Who is at risk of the disorder? How is severe preeclampsia defined and how is it managed? What is eclampsia and how should it be managed in the field? What other conditions are known to occur concurrently with pre/eclampsia?

Preeclampsia manifests after the 20th week of pregnancy with the following symptoms: (1) edema, usually of the face, ankles, and hands, (2) gradual onset of hypertension, and (3) protein in the urine. Women younger than 18 experiencing their first pregnancy, women > 35 years of age, women of African American descent, and women with a history of preeclampsia, chronic hypertension, renal disease, and diabetes are all at risk of developing it. Severe preeclampsia is identified when the systolic pressure exceeds 160 mmHg or when the diastolic exceeds 110 mmHg, or when severe symptoms are present such as: headache, dizziness, nausea, vomiting, agitation, rapid weight gain, and visual disturbances. It may require the administration of magnesium sulfate to prevent seizures in addition to an emergency antihypertensive med such as labetolol or hydralazine. If left untreated, preeclampsia progresses to eclampsia which is marked by a seizure in addition to the signs of preeclampsia. Eclampsia requires magnesium sulfate administration in addition to antihypertensive meds as indicated. Preeclampsia and eclampsia typically resolve within 10 days of delivery. Other conditions that may accompany pre/eclampsia are: liver and/or renal failure, cerebral hemorrhage, abruptio placenta, and HELLP syndrome (hemolysis, elevated liver enzymes, and low platelets). Recall that your magnesium sulfate dose for seizure activity associated with pregnancy is: 1 - 4 g of a 10% solution IV/IO over 3 minutes with a maximum dose of 30 - 40 g/day.

Compare and contrast the following terms: Primigravida, primiapara, multigravida, multipara, grand multipara, and nullipara.

Primigravida: A woman who is pregnant for the first time. Primiapara: A woman who has had only one delivery. Multigravida: A woman who has had 2 or more pregnancies, regardless of their outcome. Multipara: A woman who has had 2 or more deliveries. Grand multipara: A woman who has had more than 5 deliveries. Nullipara: A woman who has never delivered.

How should non-cephalic and non-breech presentations be managed?

Rapid transport. Do not attempt to deliver in the field. You will not be able to.

What are Rh factors and how can these lead to life-threatening issues with a fetus?

Rh factors are proteins found on the surface of most RBCs. When Rh factors are not present in an individual, the person is said to be Rh-negative. When a woman is Rh-negative but is impregnated by a man who is Rh-positive and the fetus inherits this factor, the fetal blood can pass into the mother's circulation resulting in antibody production against the factor. This typically isn't an issue with first-time pregnancies, but subsequent pregnancies can result in the mother's immune system attacking the fetus' RBCs which can kill the fetus or cause erythroblastosis fetalis (a hemolytic disease) in a newborn. These newborns may be born with jaundice, anemia, and hepatomegaly.

How much blood loss is common postpartum? What is the difference between early and late postpartum hemorrhage?

The average blood loss for woman during childbirth is 150 mL, and > 500 mL is considered to be postpartum hemorrhage. Early postpartum hemorrhage is the most common type and occurs within 24 hours of delivery. Less commonly, late postpartum hemorrhage is when bleeding continues for up to 6 weeks postpartum.

What signs and symptoms indicate that the placenta is ready to deliver?

The first sign is the mother will report that her contractions are starting again. The end of the umbilical cord protruding from the vagina lengthens, and blood gushes from the vagina. When this occurs, instruct the mother to bear down again so as to deliver the placenta.

How should fetal distress be assessed in the field?

The only real measure of this in the field is the mother's reporting of fetal movement which she's likely quite aware of. If she reports no movement or decreased movement, treat that seriously and transport rapidly to the hospital.

What occurs during the third stage of labor? How long does it last.

The last stage lasts from the time the newborn is birthed until the time the placenta is expelled from the vagina. It lasts roughly 5 - 60 minutes in both, nulliparous and multiparous women.

What position should the mother be placed in during childbirth?

The lithotomy position (supine with knees bent/raised) is the most common as it's easiest for those assisting in the delivery, but it makes things harder for the woman who has to push against gravity. Ultimately, the mother should be allowed to assume whatever position is most comfortable so long as it doesn't endanger the baby. The alternative positions include: standing, semi-fowlers, kneeling, and side-lying.

What occurs during the second stage of labor? How long does it last.

The second stage begins with crowning, although a few positional changes are required to get here. First, the head of the fetus descends and flexes (chin to chest) to enter the birth canal. Next is internal rotation, such that the face is toward the mother's rectum, followed by extension, as the head tilts such that the crown of the head may be seen at the vaginal opening. Contractions grow more intense and occur ever 2 - 3 minutes. The mother's heart rate increases and she becomes diaphoretic. She tends to bear down with each contraction and may feel the urge to have a bowel movement. This stage lasts through the delivery of the newborn and lasts an average of 1 - 3 hours in a nulliparous woman and 5 - 30 minutes in a multiparous woman.

What is an amniotic fluid embolism? How do these women present and how are they treated?

This is a life-threatening but incredibly rare condition hardly ever seen in the hospital. It occurs when amniotic fluid gets through the umbilical vein and into the mother's circulation where it causes an allergic reaction-like response that leads to coagulopathies, cardiac and respiratory collapse, and eventually death. Signs and symptoms include a sudden onset of respiratory distress and hypotension. Many women are cyanotic and have seizures. They eventually go into cariogenic shock, become unresponsive, and go into cardiac arrest. Field management is focused on supporting vital systems and rapid transport. An emergency cesarian section will likely be performed in the ED to try to save the baby.

How should intrauterine fetal deaths be managed in the field?

This is defined as death of a fetus after 20 weeks' gestation and there are a number of factors that can cause intrauterine death, ranging from infection, to genetic disorders, to poorly controlled diabetes, and so on. Typically the cause of death is not known and labor may not be induced for 2+ weeks after death. The labor is the same as in a healthy baby but the fetus may have skin blisters, skin sloughing, a dark discoloration, and gross deformity depending on the degree of decomposition. Do not attempt resuscitation on an obviously dead baby. All care should focus on the mother.

How should seizures be managed in pregnant patients?

Treatment is difficult because Valium and phenobarbital can both cross the placental barrier causing fetal distress. For this reason, the recommended treatment is magnesium sulfate - especially in patients with eclampsia - and high-flow oxygen. Despite my normal rant against mindless oxygen administration due to the cerebral effects of hyperoxia, it's actually important here as the fetus will become hypoxic before the mother will. Potential complications of seizures are: abruptio placenta, hemorrhage, disseminated intravascular coagulation, and death.

What changes occur with multiple gestation?

Twins are smaller than single newborns and thus delivery is usually easier. Be wary of the possibility of a second fetus if the baby is particularly small or if the abdomen remains large after the first birth. Be mindful that if there are twins, you want another unit responding to manage possible complications (now there are 3+ patients). Note whether there is one placenta or two. If there are two umbilical cords connected to one placenta, they're monozygotic. If there's only one umbilical cord, they're dizygotic and there's a second placenta to be delivered. Typically, a second baby is delivered within 45 minutes of the first delivery and contractions begin ~10 minutes thereafter.

What is the most common type of fetal presentation at birth? How should other cephalic presentations be managed?

Typically, the baby comes out in the vertex (top-of-head) position. The exact position can vary, and an occiput-posterior (face up) position may indicate a prolonged labor time, a military (head in-line) presentation may be incredibly painful and complicated, etc. If you encounter one of these abnormal presentations and the newborn's head doesn't externally rotate, support the mother and baby and transport rapidly.

When should diazepam be administered to a seizing pregnant patient? What is the dose administered?

Valium is used principally by EMS to treat seizures but is only indicated in the case of pregnancy if the patient's seizures do not respond to the mag sulfate. Its dose for seizures is 5 mg IV over 5 minutes or 10 mg IM.

At what point do organs begin to develop in a fetus?

Week 3: The rudiments of the central nervous system, cardiovascular system, spine, and portions of the skeletal system begin to appear. By the end of the week, an S-shaped heart begins to beat and blood cells produced in the yolk sac begin to circulate. Week 4: The placenta begins to develop. Weeks 4 - 8: The major organs and body systems form. This is the period during which drugs, medications, and alcohol are most harmful to the fetus.

What is placenta previa and how does it present?

When the placenta is implanted low in the uterus and partially or fully obstructs the cervical canal as it grows. This condition is the leading cause of painless vaginal bleeding in the 2nd and 3rd trimesters, with the majority of problems occurring near term as the cervix attempts to dilate. The chief complaint is painless vaginal bleeding with the blood often being bright red. Fetal heart sounds and movement remain normal, as the blood supply to the fetus is not directly affected. The uterus is soft and non-tender. Complications can include disseminated intravascular coagulation, hemorrhage, and low fetal birth weight.

What is supine hypotensive syndrome? How does it occur, how do these women present, and how should it be managed in the field?

When the pregnant mother is supine, the uterus can compress the inferior vena cava resulting in severely decreased venous return to the heart. This primarily occurs during the 3rd trimester of pregnancy. It can occur naturally if the mother falls asleep on her back, and it can sometimes occur while sitting upright. Left uncorrected, it can lead to maternal hypotension and subsequent fetal distress secondary to placental hypoperfusion. Nausea, dizziness, tachycardia, and anxiety are all early signs, progressing to difficulty breathing and syncopal episodes. Predisposing factors include hypovolemia, and management consists of placing the patient left-lateral, elevating her right hip (typically with a blanket), and treating underlying causes (i.e. fluid administration). In addition, you must monitor vital signs - especially blood pressure - and obtain a 12-lead ECG.

What is meconium and what does it look like? What indicates meconium aspiration and how should it be managed?

While in utero, the fetus ingests lanugo (fine, downy hairs), mucus, amniotic fluids, and several other elements, which are stored in the fetus' intestines and will constitute the first bowel movement - called meconium - which is odorless, green-black in color, and tar-like in consistency. Fetal distress can cause the fetus to have a bowel movement in utero which can then be aspirated. There's no real way to know until birth when the amniotic fluid should normally be found to be clear. A yellow tint indicates that the meconium has been in the fluid for a while, while a green-black color (especially with visible particulate) indicates recent passage. Airway management really depends solely on presentation, and suctioning is not recommended if the newborn is breathing vigorously. In hospital, the newborn will likely require treatment for chemical pneumonia.

What should be assessed if delivery is imminent?

You will not have time to perform an extensive physical exam but should attempt to do the following: 1. Assess the woman's vital signs. If her blood pressure is elevated or if her hands and face appear puffy, test the deep tendon reflexes at the knees. Any of those signs indicates preeclampsia and you must be prepared to manage seizures before, during, or after birth. 2. Try to estimate the gestational age. Palpate the abdomen to estimate the height of the uterus. If the fundus (the top of the uterus) is palpable just above the symphysis pubis, the gestational age is 12 - 16 weeks. If it's palpable at the umbilicus, it's ~20 weeks. If the fundus reaches all the way up to the xiphoid, the fetus is at or near full term. 3. Listen for fetal heart tones. A fetal heart rates < 120 indicates a fetus in distress. Bear in mind that you obviously require a doppler stethoscope for fetal heart auscultation to be possible.

Where should the umbilical cord be clamped following birth?

~4" from the baby and then 2" from the first clamp, ~30 seconds after delivery.