THIOPENTAL IN CSF AND SERUM CORRELATES WITH PROLONGED LOSS OF CORTICAL ACTIVITY

Barbiturate coma is initiated in brain-injured patients whenever eleva ted intracranial pressure remains unresponsive to other therapeutical strategies. However, barbiturates alter cortical activity resulting in difficulties in clinical evaluation. Therefore, we investigated the i mpact of long-term thiopental administration on responsiveness to exte roceptive stimuli in relation to pharmacokinetics of thiopental in CSF and serum. Long-term infusion increases thiopental levels which remai n elevated for 6 and 9 days in CSF and serum, respectively, after term ination of its administration. Prolonged unresponsiveness to exterocep tive stimuli correlates with persisting thiopental in CSF and serum. T hus, quantitative analysis of thiopental in serum becomes indispensabl e in predicting the length of drug-induced neurological impairment and in avoiding misinterpretation of the neurological status.