INTRAPERITONEAL INJECTION 



II 



INTRAPERITONEAL injection is employed most frequently 



Intraperito- among rabbits and guinea-pigs. The main danger associated 



neal with this method is possible injury to the intestines; but by 



Injection, heeding the following advice, this can be prevented. The 



animal should be fixed or held head down. In this position, 

 the loops of intestines tend to sink toward the diaphragm. This is 

 further helped along by gentle downward massage over the abdomen 

 thus leaving an area, above the bladder, which is sometimes free from 

 intestines. Another protective 

 measure consists in using a blunt 

 canula which can be made by 

 breaking off the sharp point of the 

 needle. As it is at times difficult 

 to pierce the skin with this blunt 

 instrument, it is advisable to pre- 

 viously make a minute incision 

 through the cutis and subcutis 

 with a sharp pair of scissors and 

 pass the needle through this small 

 opening. The needle should not 

 be plunged directly into the peri- 

 toneal cavity, because at the with- 

 drawal, the injected fluid easily 

 escapes through the punctured 

 opening. First, it is inserted sub- 

 cutaneously upward, in the long di- 

 rection of the animal ; then the hand 

 is raised and the needle forced 

 horizontally forward through the 

 peritoneum, thus leaving the open- 

 ing in the peritoneum at a 

 different level than the one through the muscles and fascia, thereby 

 making the escape of fluid more difficult. One readily realizes that 

 he has gone through the peritoneum by a relaxation of the reflex ab- 

 dominal rigidity (Fig. 4) . 



For the intraperitoneal injection in guinea-pigs, Friedberger has devised 

 a procedure which is very satisfactory and furthermore does away with 

 the necessity of an assistant. It can also be employed in Pfeiffer's test 

 for the removal of exudates from the peritoneal cavity. The guinea-pig 

 is allowed to creep into the breast pocket of the laboratory gown until 

 its head and thorax are inside of the pocket. Its hind legs are grasped 

 between the middle and ring fingers of the left hand and flexed on its back, 

 thus giving a free exposure of the lower parts of the abdomen (Fig. 5). 



FIG. 4. Intraperitoneal injection of rabbit. 

 (After Uhlenhuth.) 



