An investigation was made of the employment of ketamin as the sole anaesthetic in general surgery, using continuous infusion of a 1% solution for both induction and maintenance in 118 cases. ECG was monitored and arterial pressure was measured invasively. Central venous pressure was also determined in 10 cases. Changes in serum enzyme values during and after surgery were examined in 35 patients. Blood samples were withdrawn before induction, after the return to consciousness, and 24 hr after the operation. Side-effects were common, but slight. Five patients suffered from nightmares, but these were persons with marked imaginative activity and a melancholic nature. Cardiocirculatory function was satisfactory. In particular, peripheral perfusion was excellent in all cases.