Principles of intensive care in neurosurgery

Tsarenko S.V., Krylov V.V., Vakhnitskaya O.V.

(Sklifosovsky Research Institute of Emergency Care Moscow, Russia)

Suggested principles of intensive care are based on experience of treatment and research, carried out in the Neurosurgical Resuscitation Department of the Sklifosovsky Research Institute of Emergency Care in 01.01.96-01.12.99. More than 1800 patients with severe craniocerebral trauma (CCT) and cerebrovascular diseases were treated in the Department during this period. About 70% of admitted patients were in a soporific state or coma (10 according to Glasgow Coma Score).

The basis of intensive care in neurosurgery is prevention and treatment of secondary cerebral ischemic attacks. A patient's state is estimated with the help of neuromonitoring, which includes cerebral oximetry, transcranial Doppler, measurement of intracranial pressure (ICP), some indices of blood gas composition and central hemodynamics. While choosing an algorithm of infusion support, it is necessary to find a leading pathophysiologic mechanism of intracranial hypertension for ensuring sufficient cerebral perfusion. Limited quantity of fluid and use of dehydrating drugs are indicated in obstructive hydrocephalus. Active infusion therapy for providing sufficient CPP should be used in the absence of liquor outflow. Dehydration in these patients is carried out only at the peak of ICP increase with the purpose of prevention of brain dislocation and under conditions of preserved liquor spaces. Dehydrating drugs have no substrate for their effect in diminished liquor intracranial spaces and their use can aggravate disorders of cerebral perfusion.

A safe and effective measure of ensuring brain perfusion in high ICP is ionotropic support with sympathomimetics, which increase CPP without ICP growth. Monitoring of a cardiac rhythm allows to avoid life-threatening arrhythmias. Excessive loss of fluid due to increased diuresis is treated by increase of infusion up to 80-120 ml/kg/day. Use of hypotensive drugs should be limited, as they do not reduce ICP and decrease of systemic blood pressure can result in cerebral ischemia.

Progressive neurologic disorders are an indication for artificial and assisted artificial pulmonary ventilation (APV and AAPV). Oxygenation of the injured brain is achieved by increasing oxygen content in a breathing mixture up to 0.4-0.6. It is necessary to carry out APV and AAPV, using a mode, which permits to avoid increase of both intrathoracic and intracranial pressure. A sharp change of ventilation minute volume (VMV) is an undesirable phenomenon. Hyperventilation can lead to aggravation of brain ischemia due to hypocapnia and cerebral vasospasm. Considerable increase of carbon dioxide content, caused by hypoventilation or quick normalization of initially high VMV, can result in growth of ICP due to hyperemia of the brain.

Patency of the tracheobronchial tree is of principal importance for prevention and treatment of pneumonias. Tracheostomy, supported by ventilation during 5 days, is compulsory. Antibiotics should be prescribed either on the basis of sensitivity of identified microorganism or use of reserve preparations. Efficacy of antibiotics can be ensured by deliberate refusal from use of drugs, which lost their active effect 3-6 months ago. A peculiar attention should be paid to immunotherapeutic impact on neutrophils, being the main effector link in antimicrobial protection. Medicamental stimulation of the gastrointestinal tract and parenteral feeding should be started at an early stage. It allows to get two-threefold decrease of a number of stress erosions and gastrointestinal bleeding. This scheme of treatment, used in the above-mentioned Department for patients with the most severe diseases and craniocerebral injuries, made it possible to achieve 6% and 8% reduction of mortality in CCT and cerebrovascular pathology respectively. According to data of postmortem examination, the rate of pneumonia reduced by 21%.