3372
Flow and metabolism were measured 5 - 13 days after the subarachnoid haemorrhage by a modification of the classical Kety - Schmidt technique using xenon - 133 i . v . Anaesthesia was maintained with an inspired isoflurane concentration of 0 . 75 % ( plus 67 % nitrous oxide in oxygen ) , during which CBF and CMRO2 were 34 . 3 + / - 2 . 1 ml / 100 g min - 1 and 2 . 32 + / - 0 . 16 ml / 100 g min - 1 at PaCO2 4 . 1 + / - 0 . 1 kPa ( mean + / - SEM ) .
 subarachnoid haemorrhage, xenon, isoflurane, nitrous oxide, oxygen
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Disease, Chemical 
Text: {0} 
Answer:
 subarachnoid haemorrhage, xenon, isoflurane, nitrous oxide, oxygen