From the Guidelines
Hypoxic ischemic encephalopathy (HIE) in adults should be managed with a multidimensional approach, including cerebral imaging, electroencephalogram (EEG), and laboratory determination of neuron-specific enolase, to assess prognosis and guide therapy limitation discussions with relatives, as recommended by the most recent guidelines 1.
Management of HIE
The management of HIE involves several key components, including:
- Stabilizing vital functions and implementing targeted temperature management (TTM) to reduce cerebral metabolic demands and mitigate secondary injury
- Maintaining adequate cerebral perfusion pressure (CPP >60 mmHg) and ensuring normoglycemia (blood glucose 140-180 mg/dL)
- Treating seizures with antiepileptic medications, such as levetiracetam, and preventing secondary complications like infections
- Continuous EEG monitoring to detect subclinical seizures
Prognostication and Therapy Limitation
Prognostication should be delayed until at least 72 hours after cardiac arrest and normothermia, using a multimodal approach including neurological examination, electrophysiological studies, and neuroimaging 1. If the prognosis assessment shows no prospect of recovery of cerebral functions and regaining consciousness, a therapy limitation should be discussed with the relatives, taking into account comorbidities.
Palliative Care Aspects
In patients with HIE and delirium, palliative care aspects should be considered, including the treatment of epileptic seizures that affect quality of life, even with a bad prognosis, and the use of alternative modes of administration for antiepileptic medications 1. Open communication and explanation of the clinical situation are crucial in managing delirium, and non-medicinal and medicinal components should be used to treat delirium, with haloperidol being an option for hyperactive delirium.
From the Research
Definition and Causes of Hypoxic Ischemic Encephalopathy
- Hypoxic ischemic encephalopathy (HIE) is a brain injury caused by inadequate blood supply and oxygen deprivation, often occurring in adults due to cardiac arrest or profound hypotension 2.
- The clinical pattern and outcome of HIE depend on the severity of the initial insult, the effectiveness of immediate resuscitation and transfer, and the post-resuscitation management on the intensive care unit 2.
Diagnosis and Prognosis of HIE
- Clinical assessment of HIE is difficult due to sedation, neuromuscular blockade, ventilation, hypothermia, and inotropic management 2.
- Investigations such as brain MRI and EEG patterns can provide valuable information on the severity of the injury and the likelihood of a good outcome 2.
- There is no entirely reliable algorithm of clinical signs or investigations that allow a definitive prognosis, but a combination of careful observations and ancillary investigations can inform the likely outcome and guide management 2.
Treatment and Management of HIE
- Therapeutic hypothermia is the main therapy in clinical practice, although its efficacy remains to be investigated 3.
- Several experimental treatments, including drug therapy and stem cell therapy, are being explored to manage infants with HIE, exhibiting certain neuroprotective effects 4, 5.
- Employing drug therapy or stem cell therapy as adjunctive treatments to hypothermia therapy holds great significance in improving the quality of life for HIE patients 5.
Outcome and Survival Rate of HIE
- The prognosis of HIE is extremely poor, with only a quarter of patients surviving to hospital discharge, often with severe neurological or cognitive deficits 2.
- The pathophysiology of HIE is now better understood, and treatment with hypothermia has become the foundation of therapy, although several neuroprotective agents offer promise when combined with hypothermia and are entering clinical trials 6.