Remember that the evaluate, identify, intervene sequence of the systematic approach algorithm is essential for the management of each system during the post-cardiac arrest phase. The following goals and interventions are carried out using this sequence from the systematic approach algorithm.
There are two goals that are included in neurologic management for immediate post-cardiac arrest care.
Preserve brain function.
Prevent secondary neurologic injury.
The preservation of brain function and the prevention of secondary neurologic injury centers around the following priorities: maintain adequate brain perfusion, maintain normal intracranial pressure, maintain normal blood glucose, prevent and treat seizures, and provide Targeted Temperature Managment (TTM).
The ongoing neurological evaluation consists of monitoring, physical examinations, lab tests, and diagnostic tests.
- Core temperature
- heart rate and systemic blood pressure
- Neuro assessments: (pupil responses, Glasgow coma scale, corneal reflexes, other reflexes)
- signs of impending cerebral herniation
- signs of seizure activity
- other abnormal neuro findings
- bedside blood glucose
- serum ionized calcium
- toxicology studies
- cerebral spinal fluid
- CT Scan
- EEG Electroencephalogram
If the continuous evaluations/assessments above indicate that the current interventions are adequate to preserve brain function and prevent secondary neurologic injury then the interventions will continue to be carried out.
If the continuous evaluation, at any time, indicates that the current interventions are inadequate to preserve brain function and prevent secondary neurologic injury then appropriate interventions will need to take place to correct the problem that is identified.
- Maintain Adequate Brain Perfusion:
Supporting cardiac output and arterial oxygen content is the primary method for optimizing brain perfusion. (See post cardiac arrest management of cardiac and respiratory system)
Avoid hyperventilation. Hyperventilation can result in worsening brain ischemia by inducing cerebral vasoconstriction as the PaCO2 falls.
- Maintain Normal ICP:
Basic interventions that can help in maintaining a normal intracranial pressure are to elevate the head of the bed to at least 30° (if not contraindicated), keep head midline, and provide adequate ventilation and avoid hyperventilation.
More advanced interventions for the management of increased intracranial pressure include prevention of brain herniation by the following:
**administer mannitol or hypertonic saline IV
**mild hyperventilation (If signs of impending brain herniation are present, mild hyperventilation can be used temporarily to cause vasoconstriction. This vasoconstriction reduces cerebral blood flow and may decrease the risk of brain herniation.)
**neurosurgical consultation when traumatic brain injury or intracranial hemorrhage is present.
- Maintain Normal BG:
There is sometimes an increased demand for blood glucose during the post arrest phase because of the increased metabolic demands placed upon the patient. Effort should be made to maintain normoglycemia. Hypoglycemia should be treated and, hyperglycemia should be avoided due to its association with poor outcomes in critically ill children.
- Prevent and Treat Seizures:
The prevalence of seizures in the post cardiac arrest phase is high, and they are associated with increased mortality. Post cardiac arrest seizures have a number of different causes including electrolyte imbalances, hypoglycemia, toxins, and increased ICP.
**If seizures occur, treat them aggressively using IV benzodiazepines
- Provide TTM (Targeted Temperature Management):
Normothermia: 36 to 37.5°C
Hyperthermia: 32 to 34°C
Fevers can significantly increase the metabolic oxygen demand in children. For every degree Celsius in temperature elevation above 37.5°C, this results in a 10–13% increase in metabolic oxygen demand.
In light of this, prevention of fever and therapeutic hypothermia may be beneficial should be considered important adjuncts in the post cardiac arrest phase.
Fevers greater than or equal to 38°C should be aggressively treated and prevented with antipyretics, cooling devices, other cooling procedures.
The temperature in the post cardiac arrest phase should be maintained between 32°C and 37°C unless the hypothermia is suspected to be compromising the patient’s recovery.
The goal of TTM for out-of-hospital cardiac arrest patients who remain comatose is:
5 days of continuous normothermia
2 days of continuous hypothermia then 3 days of continuous normothermia.
The goal of TTM for In-hospital cardiac arrest patients who remain comatose is to provide targeted temperature management that prevents and aggressively treat fevers greater than or equal to 38°C.