Respiratory Changes After Open-heart Surgery

Abstract

1-0 to 1-5 mg./kg., one hour before operation. Anaes- thesia was induced with thiopentone, 50 to 250 mg., and muscular relaxation was obtained with D-tubocurarine, 15 to 30 mg. Respirations were controlled using a mixture of nitrous oxide 70% and oxygen 30% from a non- rebreathing system on a mechanical ventilator, except during the period of total cardiopulmonary bypass, when the lungs were held inflated with a mixture of helium, or nitrogen, and oxygen. Small doses of pethidine, 10 to 545 on July 17,