Study on indication of unilateral pulmonary artery occlusion test in patients undergoing pneumonectomy

We tried to establish an indication of unilateral pulmonary artery occlusion test (UPAO), by analyzing the preoperative data of UPAO, overall and regional pulmonary function tests, and arterial blood gas in 55 patients who were intended for pneumonectomy. Our limits of functional indication for pneumonectomy were PPA less than or equal to 25 mmHg or TPVRI less than or equal to 700 dyne.cm-5.m2. PPA correlated with the inverse of contralateral FEV1.0/BSA (FEV section 1.0) and DLCO/BSA (section DLCO), which were calculated by multiplying preoperative values by contralateral ventilation fraction. TPVRI correlated with age, the inverse of PaO2, the inverse of FEV section 1.0, and the inverse of section DLCO. Multiple regression analysis yielded the equation, TPVRI approximately p = 1120/section DLCO + 24800/PaO2 + 6.40 X Age -506. In order to make false negative zero, the values of each parameter were as follows: age greater than or equal to 55, PaO2 less than or equal to 85 mmHg, FEV section 1.0 less than or equal to 0.8 L/m2, section DLCO less than or equal to 6.0 ml/min/mmHg/m2 and TPVRI approximately p greater than or equal to 450 dyne.sec.cm-5.m2. The specificities of each parameter were 18.6%, 20.9%, 39.2%, 40.4% and 59.0%. Therefore, in order to make false positive patients least, the criteria of TPVRI approximately p greater than or equal to 450 dyne.sec.cm-5.m2 should be used.