Differential pulmonary vein gases predict primary graft dysfunction

Background. Donor arterial blood gas measurements correlate poorly with lung allograft function in the recipient. We assessed the utility of reduced pulmonary vein gas (PVG) partial pressure of oxygen (Po-2) in predicting the incidence of primary graft dysfunction. Methods. While the donor was ventilated with 100% oxygen, superior and inferior pulmonary veins were directly aspirated bilaterally and pulmonary venous Po-2 measured. A Po-2 of less than 300 mm Hg was considered subnormal. These values were assessed for predictive value in terms of primary graft dysfunction in univariate and multivariate analysis. Results. In 112 of the 201 lung and heart-lung transplants performed during the period January 2000 to December 2004, full PVGs were available for analysis. The number of pulmonary veins with sub-normal PVG correlated significantly with the incidence of severe primary graft dysfunction posttransplant in univariate (p = 0.01) and multivariate analysis (hazard ratio 2.35, p = 0.016). When analyzed separately, this correlation remained significant for recipients of single or bilateral transplants alone. No correlation existed between arterial Po-2 at donor referral and incidence of primary graft dysfunction. Median duration of ventilation, intensive care unit stay, and 30-day and 90-day mortality were not significantly different for those with any subnormal PVG compared with those with all values in the normal range. Conclusions. Differential PVGs are a useful tool in the assessment of donor lung function before procurement. It is a helpful indicator of whether preischemic dysfunction is localized or diffuse, and can be used to predict the extent to which ischemia and reperfusion will exacerbate any existing abnormality.