摘要:

An enclosed gas-filled space in the body will expand if gas within it is less soluble than the gas respired. Blood arriving at such a space can discharge a greater quantity of the soluble gas into the space than that blood can take up, assuming the tension gradient of each gas is equal. This results from the greater capacity of blood for the more soluble agent. When air was placed in the intestinal lumens of 3 dogs and nitrous oxide respired, intestinal gas volume increased 75 to 100 per cent in two hours and 100–200 per cent in four hours. Similarly, 300 ml. of air placed in the pleural space doubled in volume in 10 minutes, tripled in 45 minutes, and in one dog quadrupled in two hours. Nitrous oxide concentrations rose concomitantly in both the intestinal and pleural spaces. With cither gas in the intestine or in the pleural space, no volume changes were seen when the animal respired oxygen and halothane alone. These results suggest that nitrous oxide is relatively contraindicated in cases of intestinal obstruction or pneumothorax.

ISSN:0003-3022    

出版商:OVID    

年代:1965

数据来源: OVID

摘要:

An increase in cerebrospinal fluid pressure incurs in dogs and humans anesthetized with nitrous oxide after air has been injected into the cerebral ventricles. The mechanism for the increase in pressure is felt to be due to the difference in blood solubility between nitrous oxide and nitrogen. Nitrous oxide, being 30 times more soluble in blood than nitrogen, is carried to the air-containing ventricles in a greater quantity than the amount of nitrogen that can be carried away from the ventricles. The result is an increased number of molecules within the ventricles and an increase in intraventricular pressure. This pressure increase might prove fatal, especially in an individual whose cerebrospinal fluid pressure is already elevated. Either the avoidance of nitrous oxide anesthesia or the use of nitrous oxide as the contrast gas would eliminate the rise in pressure.

ISSN:0003-3022    

出版商:OVID    

年代:1965

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:1965

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:1965

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:1965

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:1965

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:1965

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:1965

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:1965

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:1965

数据来源: OVID