Hypoxic ischemic encephalopathy (HIE) lawyer Leon Walsh discusses how HIE can cause brian injury – and what long-term effects this may have on a child.
The term birth asphyxia refers to a baby being deprived of oxygen during or near the time of birth. When a baby experiences birth asphyxia, she is often diagnosed with hypoxic ischemic encephalopathy (HIE). HIE is a brain injury that occurs when there is reduced blood flow and oxygen in the baby’s brain. Sometimes, babies recover from HIE, and there is no permanent brain damage. Other times, however, babies who experienced HIE are left with permanent brain damage, which can cause problems that are minor and affect only a few areas of the body, to problems that are severe and affect many areas of the body. What parts of the body the brain damage affects depends on which part of the brain is injured and the severity of the brain damage.
THE LONG-TERM EFFECTS OF HYPOXIC ISCHEMIC ENCEPHALOPATHY (HIE)
The severity / extent and location of brain damage can help predict the long-term effects of HIE, as well as what types of long-term problems the baby may experience. Listed below are regions of the brain and which body functions these parts of the brain help control. The major parts of the brain are the cerebrum, cerebellum, and brain stem – and all three of these contain both gray and white matter.
The cerebrum is the largest part of the brain and it contains nerve centers that control movement, memory, reasoning, perception, and judgment. The cerebrum’s surface is known as the cerebral cortex, and it helps coordinate motor and sensory information. The cerebrum has four lobes, and each of these lobes plays an important role in brain function.
Frontal Lobes of the Cerebrum
The frontal lobes of the cerebrum play a crucial role in high-level functions such as movement, attention, planning, and judgment. These lobes also manage emotions and impulse control, and they majorly influence personality.
Parietal Lobes of the Cerebrum
The parietal lobes are behind the frontal lobes, and their function is to organize and interpret sensory information that is sent from other regions of the brain.
Temporal Lobe of the Cerebrum
Located near the ears, the temporal lobes of the cerebrum play an important role in functions such as language comprehension, visual memory (i.e. facial recognition), and understanding emotions.
Occipital Lobe of the Cerebrum
The occipital lobe of the cerebrum is located at the back of the head and contains the primary visual cortex, which controls vision. The occipital lobe is critical in both receiving and processing visual information and thus is involved in reading and reading comprehension.
The cerebellum is located behind the top of the brain stem, where the brain connects with the spinal cord. The cerebellum is only about 10% of the brain’s total weight, but it contains about 50% of the brain’s neurons.
The cerebellum plays a significant role in motor control (voluntary movement). With normal cerebellum function, muscle movements will be smooth and the child will have good posture, balance, coordination, and speech. Damage to the cerebellum would not cause paralysis, but it cause balance problems, inefficient movement, tremors, and other motor control issues. Damage to the cerebellum also makes it harder for children to learn new motor tasks.
The Brain Stem
Located in front of the cerebellum, the brain stem relays signals from the brain to the spinal cord. It helps regulate functions such as breathing, heart rate, and blood pressure, and is critical to survival. The brainstem has 3 major parts: the pons, midbrain, and medulla oblongata.
As the largest part of the brain stem, the pons is involved in the transmission of sensory information. It also controls movements of the face.
The midbrain is involved in processing visual and auditory information, and it also plays a role in controlling eye movement.
Connecting the brain stem to the rest of the brain, the medulla oblongata controls the heart and lungs, and it regulates critical functions such as swallowing and breathing.
PATTERNS OF BRAIN INJURY FOLLOWING HIE
The two main patterns of brain injury are acute near total asphyxia (also known as basal ganglia-thalamus pattern of injury) and partial, prolonged asphyxia.
PARTIAL, PROLONGED ASPHYXIA / WATERSHED PATTERN OF INJURY & HIE
When the baby’s brain experiences less severe, more prolonged hypoxic / ischemic insults, there is a mechanism that protects the deeper structures of the brain called shunting. When a hypoxic ischemic insult causes shunting, blood gets directed away from the cerebral cortex to the deeper structures, such as the basal ganglia and thalamus. Thus, during prolonged (30 minutes or more), less severe hypoxic / ischemic episodes, the cerebral cortex (the outer layer of brain tissue) suffers reduced blood flow, while the deep gray matter is relatively spared from injury. The pattern of injury is mainly cortical damage in the watershed and parasagittal regions.
This partial prolonged asphyxia / watershed pattern of injury can be caused by Pitocin and Cytotec use, which are labor induction drugs that can cause contractions to be so strong and frequent (hyperstimulation / tachysystole) that the blood vessels in the placenta are almost continuously compressed, causing a reduction in the amount of oxygen-rich blood going to the baby. When the uterus is essentially in a constant state of contraction, it is called hypertonus. Hyperstimulation, tachysystole and a hypertonic uterus can cause oxygen deprivation in the baby that gets progressively worse.
Maternal hypertension (high blood pressure) and hypotension (low blood pressure) also can cause a baby to experience partial prolonged asphyxia. Maternal blood pressure problems can be caused by many conditions, including dehydration, a maternal infection, drugs used with an epidural, and anesthesia.
Partial prolonged asphyxia / watershed pattern of injury can also be caused by umbilical cord compression caused by a nuchal cord (cord wrapped around the baby’s neck) or other issues, oligohydramnios (low amniotic fluid), placental insufficiency, and inadequate or delayed resuscitation of the baby at birth.
ACUTE NEAR TOTAL ASPHYXIA (ALSO KNOWN AS BASAL GANGLIA-THALAMUS PATTERN OF INJURY) & HIE
When the hypoxic ischemic insult is sudden and severe (total or near total asphyxia), the regions of the brain that have high metabolic activity (high energy demands) – such as the basal ganglia, thalamus and brain stem (deeper brain structures) – become injured. Also, total asphyxia prevents the adaptive mechanism of shunting blood to these deeper structures, so they become damaged, while the cerebral cortex will typically be spared from injury.
Conditions that can cause acute near total asphyxia include uterine rupture, prolapsed umbilical cord, placental abruption and terminal bradycardia (slow heart rate) in the baby.
MIXED INJURY PATTERN & HIE
Babies may also experience a mixed injury pattern. This occurs when the baby experiences both partial prolonged asphyxia / a watershed pattern of injury AND acute near total asphyxia.
BRAIN INJURY IN PREMATURE BABIES VERSUS TERM BABIES
While term babies with HIE most commonly experience 1.) a watershed predominant pattern of injury involving the white matter, especially in the vascular watershed (extending to cortical gray matter following a severe hypoxic ischemic insult), and 2.) a basal ganglia predominant pattern involving the deep gray nuclei and perirolandic cortex (involving the cortex in severe injury), premature babies most commonly experience focal non-cystic white matter injury. Premature babies with HIE and resultant white matter injury and related problems are often diagnosed with periventricular leukomalacia (PVL), which can cause cerebral palsy and other long-term conditions. PVL involves the death of small areas of brain tissue around the ventricles. The damage creates holes in the brain. “Leuko” is in reference to the brain’s white matter. “Periventricular” is in reference to the area around the ventricles.
CONDITIONS THAT CAN BE CAUSED BY HIE
HIE can cause a newborn to experience problems that include seizures. If the HIE results in a baby having permanent brain damage, the baby may have lifelong conditions such as cerebral palsy, motor disorders, seizure disorders, periventricular leukomalacia (PVL), hydrocephalus, intellectual disabilities, and / or developmental delays.
THE HYPOXIC ISCHEMIC ENCEPHALOPATHY (HIE) LAWYERS AT GREWAL LAW ARE HERE TO HELP
If your baby was diagnosed with hypoxic ischemic encephalopathy (HIE), or if your baby experienced a traumatic birth, birth asphyxia, a brain bleed, delayed delivery, or delayed emergency C-section, please contact our team of experienced Michigan birth injury attorneys. The Michigan medical malpractice team at Grewal Law, PLLC, is comprised of attorneys and healthcare professionals, including an on-site registered nurse, pharmacist, paramedic, and respiratory therapist. We also work with the best consultants from around the country, as well as an on-site physician. Our attorneys are licensed in Michigan and Florida, and we help victims of medical malpractice and birth trauma throughout Michigan and Florida.
If your child has received diagnoses of HIE, seizures, cerebral palsy, motor disorders, periventricular leukomalacia (PVL), hydrocephalus, intellectual disabilities, or developmental delays, or if your baby experienced problems during delivery or shortly before or after birth, please call us. Our medical malpractice attorneys and medical staff are available to speak with you 24/7.
A Graduate from the Florida State University College of Law, Leon Walsh, Jr. spent several years in Florida as an assistant public defender as well as working for a civil litigation firm where he gained valuable first-chair jury trial experience in both state and federal courts. Mr. Walsh now works for Church Wyble, PC in Northville, Michigan where he focuses on medical malpractice and complex personal injury claims.