Pulmonary Diffusion Studies in Patients Undergoing Nonthoracic, Thoracic, and Cardiopulmonary Bypass Procedures

Respiratory Changes After Open-heart Surgery

“…The remainder of the desaturation was presumably due to areas of lung where ventilation and perfusion were unequal. A-lthough a number of authors (Schramel et al, 1959;Eowatt et al, 1962;Ellison et al, 1963) have demonstrated reductions in diffusing capacity after open-heart surgery, it is likely that the changes noted could be accounted for by the ventilation-perfusion inequalities present. Although Paco, is usually not greatly influenced by uneven ventilation and perfusion (Riley et al, 1951), it should be pointed out that with distribution (VA/0) abnormalities of the magnitude encountered in these studies arterial-alveolar gradients for CO2 may be present (Williams and Rayford, 1956).…”

“…In 1961, Beer, Loeschcke, Schaudig, Pasini, Auberger, Ranz, and Borst reported that there was a reduction in diffusing capacity and an increase in right-to-left intrapulmonary shunting in both patients and animals who had been subjected to thoracotomy and total body perfusion. Howatt, Talner, Sloan, and DeMuth (1962) and Ellison, Yeh, Moretz, and Ellison (1963) (1962) reported increased arterial-alveolar carbon dioxide tension differences and arterial desaturation; they attributed this to patchy atelectasis. This paper describes studies which were made on two groups of patients in an attempt to assess the effects of extracorporeal circulation on postoperative lung function.…”

Hypoxaemia after aortic valve surgery under cardiopulmonary bypass.

“…DIFFUSION This factor has been investigated using carbon monoxide uptake and shows a decrease in the early post-operative period of 25 to 40% below pre-operative values (Schramel, Cameron, Ziskind, Adam, and Creech, 1959), lasting up to 14 days. Ellison, Yeh, Maretz, and Ellison (1963) found that the decrease in carbon monoxide uptake was greater after operation under bypass than after thoracotomy alone. However, in the presence of uneven distribution of gases within the lungs, the carbon monoxide uptake is reduced by this factor alone, and in patients with a diagnosis of 'alveolar-capillary block syndrome ' Finley, Swenson, and Comroe (1962) showed that the arterial hypoxaemia could be accounted for solely on the basis of uneven distribution of ventilation in relation to blood flow.…”

Respiratory Changes After Open-Heart Surgery

“…This is illustrated in Table 1V. It may be seen from Tables III and IV and from (Schramel et al, 1959;Eowatt et al, 1962;Ellison et al, 1963) have demonstrated reductions in diffusing capacity after open-heart surgery, it is likely that the changes noted could be accounted for by the ventilation-perfusion inequalities present. Although Paco, is usually not greatly influenced by uneven ventilation and perfusion (Riley et al, 1951), it should be pointed out that with distribution (VA/0) abnormalities of the magnitude encountered in these studies arterial-alveolar gradients for CO2 may be present (Williams and Rayford, 1956).…”

“…In 1961, Beer, Loeschcke, Schaudig, Pasini, Auberger, Ranz, and Borst reported that there was a reduction in diffusing capacity and an increase in right-to-left intrapulmonary shunting in both patients and animals who had been subjected to thoracotomy and total body perfusion. Howatt, Talner, Sloan, and DeMuth (1962) and Ellison, Yeh, Moretz, and Ellison (1963) (1962) reported increased arterial-alveolar carbon dioxide tension differences and arterial desaturation; they attributed this to patchy atelectasis.…”