Hypoxic-Ischemic Encephalopathy

In severe hypoxic-ischemic encephalopathy, the mortality rate is reportedly 25-50%. Most deaths occur in the first week of life due to multiple organ failure or redirection of care. Some infants with severe neurologic disabilities die in their infancy from aspiration pneumonia or systemic infections. Medical articles state the exact cause is yet unknown. What we do know, is birth injury lawsuits have resulted in large settlements to compensate the families for ongoing medical care or the death of their child. Settlements are reached when the insurance company accepts some level of responsibility for the birth injury. This occurs when the health care providers actions deviated from the standard of care. These injuries are then referred to as "preventable." Hypoxic-ischemic encephalopathy lawsuits have also received favorable verdicts in courts. A jury pondered the evidence and the arguments of each side, rendering a verdict against the doctor. The jurors have essential found the doctors actions caused, contributed to or failed to prevent the birth injury.

Hypoxic-ischemic encephalopathy Complications

The incidence of long-term complications depends on the severity of hypoxic-ischemic encephalopathy. As many as 80% of infants who survive severe hypoxic-ischemic encephalopathy develop serious complications, 10-20% develop moderately serious disabilities, and as many as 10% are healthy. Among the infants who survive moderately severe hypoxic-ischemic encephalopathy, 30-50% may have serious long-term complications, and 10-20% have minor neurological morbidities. Infants with mild hypoxic-ischemic encephalopathy tend to be free from serious CNS complications.

Hypoxic-ischemic encephalopathy Trials

Two hypothermia trials* provided updated information on mortality and the incidence of abnormal neurodevelopmental outcomes infants with moderate to severe hypoxic-ischemic encephalopathy.^{[18, 19]} In these trials, 23-27% of infants died prior to discharge from the neonatal ICU (NICU), whereas the mortality rate at follow-up 18-22 months later was 37-38%. In these trials, neurodevelopmental outcomes at 18 months were as follows:

• Mental development index (MDI)

  • Score of 85 or higher - 40%
  • Score of 70-84 - 21%
  • Score less than 70 - 39%
• Psychomotor development index (PDI)

  • Score of 85 or higher - 55%
  • Score of 70-84 - 10%
  • Score less than 70 - 35-41%
• Disabling cerebral palsy - 30%
• Epilepsy - 16%
• Blindness - 14-17%
• Severe hearing impairment - 6%

Data from a randomized controlled trial was evaluated to determine the relationship between hypocarbia and the outcome for neonatal patients with hypoxic-ischemic encephalopathy. The results found that a poor outcome (death/disability at 18-22 mo) was associated with a minimum partial pressure of carbon dioxide (PCO₂) and cumulative PCO₂ of less than 35 mm Hg; death and disability increased with greater exposure to PCO₂ of less than 35 mm Hg. Even in the absence of obvious neurologic deficits in the newborn period, long-term functional impairments may be present. In a cohort of school-aged children with a history of moderately severe hypoxic-ischemic encephalopathy, 15-20% had significant learning difficulties, even in the absence of obvious signs of brain injury. Thus, all children who have moderate or severe hypoxic-ischemic encephalopathy should be monitored well into school age. *Gluckman PD, Wyatt JS, Azzopardi D, et al. Selective head cooling with mild systemic hypothermia after neonatal encephalopathy: multicenter randomised trial. Lancet. 2005;365:663-70. Shankaran S, Laptook AR, Ehrenkranz RA, et al. Whole-body hypothermia for neonates with hypoxic-ischemic encephalopathy. N Engl J Med. Oct 13 2005;353(15):1574-84. Contact the Clore Law Group today if your child was diagnosed with hypoxic-ischemic encephalopathy.