A controlled study of three respiratory stimulants in chronic respiratory failure

The effects of slow intravenous infusion of three different respiratory stimulants (dimefline, nikethamide and prethcamide) on minute and alveolar ventilation, blood gases and pH were studied in 18 patients with chronic pulmonary emphysema and chronic respiratory failure. For a more accurate assessment of the results of the double blind controlled trial, a factorial design in a Youden square scheme was employed. Respiratory rate, tidal volume, minute ventilation, arterial Po 2 , pH and heart rate failed to show significant changes after the intravenous infusion of the drugs. The other parameters studied (dead space, alveolar ventilation, CO 2 output, Paco 2 ) showed some differences but these were temporally similar for the three drugs. As improvement in respiratory and blood gases data was transient and slight and undesirable side-effects constant, it is concluded that the use of respiratory stimulants in management of chronic respiratory failure cannot be recommended.