≥90% of participants will understand how to care for neonates with complications at delivery.
≥90% of participants will understand how to care for neonates with complications at delivery.
After completing this continuing education course, the participant will be able to:
The transition from intrauterine to extrauterine life depends on physiologic changes that occur at the time of birth. Most of the time, this happens without difficulty, except in about 10 percent of newborns that need some intervention to help them transition. Less than 1 percent of newborns will need extensive resuscitation.1
Before birth, the placenta provides gas and nutrient exchange for the fetus from the maternal circulation. The placenta has the lowest vascular resistance and received 40 percent of fetal cardiac output. The fetal lungs are filled with fluid and have the highest vascular resistance, receiving less than 10% of the fetal cardiac output. Two right-to-left shunts occur in the fetus because of high pulmonary vascular resistance and low systemic pressure. During fetal development, a small opening called the foramen ovale is normally present in the wall between the right and left atria of the heart.2 The fetus also has a ductus arteriosus, which is an artery connecting the aorta and the pulmonary artery. The ductus allows blood to detour away from the lungs before birth.3 From the placenta, oxygenated blood flows through the umbilical vein into the abdomen of the fetus. The majority of this blood flows through the ductus venosus into the inferior vena cava and then into the right atrium. Remaining blood perfuses the liver. Less oxygenated blood from superior vena cava and the inferior vena cava distal to the ductus venosus flows from the right atrium into the right ventricle with minimal mixing with the oxygenated blood from the ductus venosus. About 90% of the right ventricular output bypasses the lung and is shunted through the ductus arteriosus to the descending aorta. This deoxygenated blood is transported through the aorta to the umbilical arteries to the placenta, where it releases carbon dioxide and waste products and collects oxygen and nutrients.3
At delivery, as soon as the cord is clamped, rapid physiologic changes occur for the neonate to have a successful transition. Alveolar fluid clearance must occur for lung aeration. Labor likely contributes to this change. The initial effective breaths of the neonate create high transpulmonary pressures, which drives out alveolar fluid from the air spaces into pulmonary vasculature. The pressure on the chest wall of the infant during delivery may also help this process. This fluid is cleared partially within a few minutes and should clear completely within 24 hours. With the first breath, intrathoracic pressure falls and allows for lung expansion.4 When the umbilical cord is clamped, the placenta is removed from neonatal circulation which causes a rise in neonatal systemic blood pressure. This decreases right-to-left shunting at the ductus arteriosus, which results in increased left-to-right shunting. This creates increased blood flow through the pulmonary arteries and lungs. There is an increased ventricular stroke volume which increases cerebral oxygen saturation. These changes stimulate closure of the ductus arteriosus.5
There are risk factors that can affect the transition at delivery. Maternal conditions such as advanced maternal age, diabetes, hypertension, or substance abuse can impact a successful transition. Fetal conditions such as prematurity, postmaturity, or congenital anomalies can also impact transition. Placenta anomalies, oligohydramnios, or polyhydramnios can impact transition. Delivery complications such as chorioamnionitis, meconium-stained fluid, antenatal asphyxia, maternal narcotics within 4 hours of delivery, or delivery with instrumentation can also impact transition.
Placental anomalies ranging from a placenta previa with a small amount of bleeding to a placental abruption in which the woman is hemorrhaging can cause mild to severe complications of the neonate at delivery. With placental abruption, the fetus can also lose a large amount of blood. This fetus is likely to be delivered and require full resuscitation as well as blood volume replacement.
If the neonate does not have regular, vigorous respirations at birth, there is a disruption to alveolar fluid clearance, lung inflation, and reduction of pulmonary vascular resistance. Causes of impaired respiratory effort can be mild and reversible, such as exposure to maternal opioids to severe and non-reversible, such as prolonged hypoxia.3 Blockage of the airway can prevent initial breaths. A blockage can be caused by a congenital malformation such as choanal atresia or the presence of meconium or mucus in the airway.3 Impaired lung function can cause respiratory distress in a newborn. Some causes of impaired lung function are external causes such as a pneumothorax or pleural effusions. Pulmonary hypoplasia can be caused by a diaphragmatic hernia that can impair lung function. Intrinsic lung disease may impact lung function and some causes are deficient surfactant in a preterm infant or transient tachypnea of the newborn in a full-term infant.
Persistent pulmonary hypertension is another cause of a complicated transition at birth. In this disorder, the pulmonary vascular resistance remains elevated after birth due to abnormal blood shunting right to left through fetal circulatory pathways. This can be a life-threatening condition. Severe congenital cardiac disease can cause difficulty for the newborn to transition to extrauterine life. Preterm infants are also more likely to have difficulties transitioning to extrauterine life.
Difficulty transitioning to extrauterine life is usually correlated to fetal circulation and respiratory issues. There are some other causes of complications that a nurse in the delivery room should be aware of. Preterm birth puts the neonate at risk for respiratory problems, hypothermia, hypoglycemia, infection, intracranial hemorrhage, and necrotizing enterocolitis. Most of these complications do not cause immediate problems at delivery (other than respiratory problems), but they are important to be aware of. Multiple gestation pregnancies are at increased risks of problems such as preterm birth, fetal growth restriction, discordant growth, and congenital anomalies. Both fetal growth restricted and discordant growth fetuses are at risk of complications at delivery, similar to that of a preterm infant. Twin to twin transfusion is a disorder where there is an uneven distribution in fetal blood flow. This can cause serious problems at delivery. These neonates can have an abnormal cardiac function, anemia, hypovolemia, or hydrops, which can all lead to the need for neonatal resuscitation at birth.6 There can be long-term problems with neurological development.
At every delivery, there should be at least one provider whose only responsibility is the newborn and this provider should have the skills to initiate resuscitation. There should also be a provider who is immediately available to carry out full neonatal resuscitation, including intubation and medications. Equipment needed for resuscitation should also be available at every delivery.7 The most widely used training program is the neonatal resuscitation program (NRP) which was developed by the American Academy of Pediatrics (AAP) and the American Heart Association (AHA) as a training program teaching principles and skills. NRP is appropriate for nurses, doctors, nurse practitioners, and respiratory therapists. Institutions should have a policy that states which staff are required to have this training.8 NRP guides the healthcare personnel on how to provide resuscitation as soon as the need is determined. During the first minute of life, all newborns are assessed to determine the need for care. The initial steps are to dry and stimulate the infant, warm the infant (and maintain body temperature), and position the airway and clear secretions if needed. If the baby is term gestation with good tone and breathing or crying, the infant may stay with mom and continue evaluation. If the infant has apnea, gasping, or a HR below 100 bpm, resuscitation should begin. NRP teaches an algorithm to be used during resuscitation.8 The algorithm is complex and tells the person using it to warm, dry, and stimulate the infant. Then if the infant is not breathing, is gasping, or has a heart rate < 100, positive pressure ventilation (PPV) should be started. There are steps to do if the PPV does not work, including repositioning the mask, giving chest compressions, and giving epinephrine. The NRP class teaches the algorithm and the skills to perform.
NPR material, including wall charts, are available here at on amazon.
Newborns will be born without complications up to 90% of the time. It is important for nurses who attend births to understand what can cause complications at delivery and how to care for neonates requiring assistance. If a fetus is known to have problems that will complicate delivery, it is best to discuss this case in an interdisciplinary group before delivery. This group can develop a plan and be ready for complications at birth.
MS is a 40-year-old female at 29 weeks and 2 days gestation. She presents to the emergency room via ambulance after a motor vehicle accident. MS is screaming in pain and clutching her abdomen. She is pale and diaphoretic. Her HR is 138, BP 90/62, temp 98.5, resp 22. She is bleeding, and her pants are soaked with blood. She states that her abdominal pain is 10/10 and won’t stop. MS is cleared for a head trauma and rushed to labor and delivery directly to the operating room.
What is likely happening? What are the risks to the neonate? What do you and the team need to be prepared for?