“…A simple waterproof mi croautoinjector would be very convenient, especially for these patients. Epidural anes thesia with continuous infusion of narcotics relieves the pain effectively [2], Various in struments are used for the operations [3], for the electrical administration of chemicals [4,5] and for the direct injection of micro amounts of drugs to single cells [6,7], Two kinds of autoinjectors were built: one is us ing gas pressure produced by electrolysis of medical-grade 7% sodium bicarbonate solu tion and the other derives its power from the catalysis of medical-grade 3.3% hydrogen peroxide solution. The latter is a very simple device which can be used for continuous drug infusion to achieve epidural anesthesia in cancer patients at the terminal stage.…”