El presente trabajo abarca los temas desarrollados en un curso para graduados realizado en el Hospital de Ni&ntilde;os de La Plata, en el mes de setiembre de 1964.<br /> En &eacute;l se ha procurado actualizar un tema de singular trascendencia m&eacute;dica, siguiendo los lineamientos impuestos por la moderna escuela danesa a cuyo frente figuran Astrup, Siggaard-Andersen, Engel y Jorgensen, quienes en el a&ntilde;o 1960 publicaron un microm&eacute;todo que permite, con muy peque&ntilde;as cantidades de sangre capilar, efectuar una determinaci&oacute;n precisa del estado &aacute;cido-base, tanto en su aspecto respiratorio como metab&oacute;lico.<br /> Asimismo se dan aqu&iacute; las bases terap&eacute;uticas, que se infieren de los valores del estado &aacute;cido-base obtenidos por este sistema.The present paper approaches the subjects developed in a post-graduated course performed in the Hospital de Ni&ntilde;os de La Plata, during the month of September 1964.<br /> In this work we have tried to realize a subject of a great medical importance following the features given by the modera Danish school led by Astrup, Siggaard-Andersen, Engel and Jorgensen, who in the year 1960 published a micromethod which allows to perform an exact determination of the acid-base status of the blood, in its respiratory as well as metabolic aspect with very small q.uantities of capillary blood.<br /> The therapeutic treatment inferred from the val&uacute;es of the acid-base status obtained by this system are also given here.