MATERNAL BLOOD-GASES, (PAO2—PaO2), PHYSIOLOGICAL SHUNT AND VD/VT IN NORMAL PREGNANCY

摘要: SUMMARY Serial measurements of maternal blood-gases, alveolar-to-arterial oxygen tension difference ( P A O2 – a ), calculated pulmonary venous admixture (physiological shunt), deadspace/tidal volume ratio V D/ T), and respiratory minute have been made in carefully selected group normal pregnant patients at 12, 24, 32 38 weeks gestation 5 after delivery. All were the semi-recumbent position with left lateral pelvic tilt. Mean arterial was consistently greater than 100 mm Hg throughout pregnancy, although value decreased from 106.4 12 to 101.8 38th week. Despite this decrease there no change T, or percentage shunt increasing gestation; nor did these values differ significantly non-pregnant same patients.