COLLECTION OF PUS. 135 



brain. This may assist in the diagnosis of obscure 

 injuries, or of the cause of a case of unconsciousness in 

 which no history can be obtained. 



Haemorrhage into the meninges is indicated by the 

 withdrawal of blood-stained fluid, but it must be 

 remembered that the first few drops may contain a 

 small quantity^ of blood which has entered the needle 

 during its passage through the tissues, while the rest is 

 clear. Blood-stained fluid may occur in meningitis, 

 and should be submitted to a full examination for 

 leucocytes and bacteria. 



Transmission of fluid to public laboratory. If the prac- 

 titioner is unable to examine the fluid the best method 

 to adopt is to collect it in a long and narrow test tube 

 (sterilised by dry heat) and to seal the neck of the tube. 

 Or he may forward it in a bottle sterilised by boiling 

 and plugged with a cork which has also been boiled, 

 but this method is not so good. 



THE COLLECTION OF PUS. 



When a simple microscopical examination has to be 

 made the collection of pus presents no difficulties, as 

 the few bacteria which may gain access from the skin 

 or the air will not lead to error. The case is otherwise 

 where cultural examinations have to be made, or where 

 the material has to be transmitted to a laboratory. 

 Here the material should be collected in a pipette. 

 This is to be at hand when the abscess is opened ; both 

 ends are to be broken off and passed through the flame 

 two or three times. The pipette should then be held 

 by an assistant or put with the end which is to be 

 inserted into the pus projecting over the side of the 

 table so as not to come into contact with any object. 



