[Changes in cerebrospinal fluid pressure in nitrous oxide anesthesia in neurosurgical patients].

By employing continual electromamometry of the cerebrospinal fluid and central venous pressures the influence of nitrous oxide on the CSE pressure was studied in neurosurgical patients operated upon following pneumoencephalography. In patients treated surgically without any preliminary pneumoencephalographic investigation the normo- and hypocapnic artificial ventilation of the lungs with a N2O and O2 mixture produced a significant drop of the CSF pressure. A nitrous oxide anesthesia applied to the patients operated on after pneumoencephalography was accompanied by a marked rise of the cerebrospinal fluid tension. In such cases an artificial hyperventilation of the lungs failed to prevent a rise of the intracranial tension.