Purpose of review: This review will examine the most important issues of
preoperative evaluation and preparation in relation to patients with deseases
affecting the central nervous system. Those patients may undergo various
forms of surgery unrelated to the central nervous system disease. We discuss
the effect of physiologic and pharmacological factors on cerebral
autoregulation and control of intracranial pressure alongside its clinical
relevance with the help of new evidence. Recent findings: Regardless of the
reason for surgery, coexisting diseases of brain often have important
implications when selecting anesthetic drugs, procedures and monitoring
techniques. Suppression of cerebral metabolic rate is not the sole mechanism
for the neuroprotective effect of anaesthetic agents. There are certain
general principles, but also some specific circumstances, when we are talking
about optimal anesthetic procedure for a patient with coexisting brain
disease. Intravenous anesthesia, such as combination of propofol and
remifentanil, provides best preservation of autoregulation. Among inhaled
agents isoflurane and sevoflurane appear to preserve autoregulation at all
doses, whereas with other agents autoregulation is impaired in a dose-related
manner. During maintenance of anesthesia the patient is ventilated by
intermittent positive pressure ventilation, at intermediate hyperventilation
(PaCO2 25 - 30 mmHg). Summary: Intraoperative cerebral autoregulation
monitoring is an important consideration for the patients with coexisting
neurological disease. Transcranial Doppler based static autoregulation
measurements appears to be the most robust bedside method for this purpose.
Type 3 Diabetes? Evaluation of the Noradrenergic System in Diabetic Rats by Underexpression of Tyrosine Hydroxylase in the Central Nervous System
