The invention of the Woodyatt1 pump for maintaining intravenous injections over protracted lengths of time has led to the suggestion of several lines of research which are being developed in the Sprague Institute. One of these is presented in this article.
The effectiveness of the in vivo action of a therapeutic agent which is used because of its bactericidal properties, in all probability depends on the same factors which operate in the in vitro action of a bactericide, the two chief of which are the time factor and the concentration factor. Either in vitro or in vivo a given bactericide in a stated length of time will act better on bacteria in a higher concentration than in a lower one, and, in a stated concentration, will act better in a long time than in a short time. (It is important to realize that the latter is not infinitely true, since