Hypoxic Ischemic Encephalopathy, or "HIE," is a diagnosis of brain injury relating to traumatic labor and delivery. "Hypoxic" means oxygen deprivation. "Ischemic" means lack of blood flow to the tissues of the body. And "Encephalopathy" means disease or injury to the brain. Taken together, the diagnosis means that the brain tissue suffered injury due to lack of blood flow and lack of oxygen. This type of injury, often catastrophic, occurs when a baby receives inadequate blood flow, or inadequately oxygenated blood, or both, during labor and delivery.
Labor and delivery is, by its nature, a stressful time for mom and baby. The process of childbirth involves contractions of the muscles of the uterus, repeated again and again, often for a period of hours. With each muscular contraction, mom and baby are stressed by physical exertion. In a normal delivery, however, the baby has sufficient strength and resilience, known as fetal reserve, to withstand the stress of uterine contractions and to make its way through the birth canal for a healthy vaginal delivery.
Sometimes, however, for a variety of reasons, babies cannot withstand the forces of childbirth. In these circumstances, cesarean section delivery is necessary to prevent injury, such as HIE, due to birth trauma.
So, how do health care professionals diagnose and prevent an ominous situation where the baby is unable to withstand the forces of childbirth? For the most part, the device they rely upon is the Fetal Heart Tracing or Fetal Heart Monitor. This device utilizes a measurement of both mom's uterine contractions and baby's heart rate to determine whether the baby has appropriate fetal reserve and whether the baby is adaptable to the stresses of labor and delivery.
Under normal circumstances, a uterine contraction will stress the baby, but the baby's brain is able to regulate its autonomic nervous system in a manner to withstand the stress. Thus, changes in heart rate provide essential messages to the health care team regarding the condition of the baby. When and if the heart rate does not respond properly to mom's uterine contractions, the health care team will be able to detect these abnormal changes on the fetal heart monitor and act accordingly and with a c-section if necessary.
For example, a normal response to a uterine contraction can be a deceleration in the fetal heart rate. If the deceleration is depicted on the monitor simultaneously with the peak of the uterine contraction, this is considered a normal and healthy response. But, if the monitor shows a deceleration well after the contraction occurs, there is something wrong. The baby's brain is not responding in a timely way. Though it has reacted to the stress of the contraction, the reaction is late, and this is an ominous sign that the baby's brain is not functioning properly, presumably because it lacks sufficient oxygen to react promptly to the stress of a contraction. When these types of "late decelerations" appear during labor, especially when they appear more than once, significant interventions are warranted, including cesarean section, to prevent significant and potentially catastrophic damage to the baby due to oxygen deprivation.
What causes oxygen deprivation? Most often, the cause is known as placental or cord insufficiency. This means that the placenta or the umbilical cord, the biological tools arising in the womb to provide blood and nutrition from mom to baby, fail to delivery sufficient blood flow, oxygen rich blood, or both to baby. When this occurs, whether due to a twisted or knotted cord, an infection, an undersized placenta, or some other defect in the cord or placenta, the baby cannot withstand the stresses of robust uterine contractions. The placental or cord defect prevents sufficient oxygenated blood from entering the baby's tissues during the time of stress.
For this reason, the fetal heart monitor has become the gold standard for monitoring the progress of labor and the health of the baby. Labor and delivery nurses at qualified obstetrical centers are expected to be highly skilled at reading, interpreting, and responding to abnormal fetal heart tracings. It is their job to monitor, minute by minute, their patients' fetal heart monitors throughout the labor and delivery process. The entire purpose of this is to avoid a catastrophic brain injury due to birth trauma and HIE. Together with a skilled and responsive obstetrician, a careful and conscientious nursing team should be able to manage almost every labor and delivery without adverse incidents.
Tragically, there are circumstances where the health care team deviates from the accepted standard of care in monitoring and responding to abnormal fetal heart tracings. When this occurs, babies and moms are helpless to prevent the catastrophic outcome. And these types of brain injuries due to HIE are often impossible to cure, leading to a lifetime of expensive and essential medical care and attention. Skilled attorneys and law firms are properly trained and experienced to review the medical records, including the fetal heart tracings, and determine whether a baby's injury was preventable and caused by medical negligence. If so, the justice system, with the help of a dedicated trial attorney, often provides a civil remedy, including significant financial compensation, to pay for the lifetime needs of these innocent children.