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One hundred consecutive patients with findings suggestive of resectable bronchogenic carcinoma were studied prospectively to determine if routine liver, brain, and bone scans (multiorgan scans) detected metastases which were not suggested by a history, physical examination, and serum chemistries. Multiorgan scans were compared with clinical evaluations in 52 patients found to have operable bronchogenic carcinoma. There was a discordance between scans and clinical evaluations in 25/153 scans (16 per cent). Two of the 22 negative scans in patients with abnormal clinical findings were false negative. Sixteen of the 17 positive scans in patients with normal clinical findings were false positive. One of the 131 scans done in patients with no evidence of metastases on clinical evaluation was true positive. These data indicate that the routine use of multiorgan scans in the initial staging of potentially resectable bronchogenic carcinoma is not justified.

Improved airway resistance following bronchodilator inhalation is not always accompanied by improvement in forced expiratory flow. We studied 241 patients with airways obstruction to learn whether changes in static lung volumes (vital capacity and function residual capacity measured by body plethysmography [FRCB]) would reveal bronchodilation not demonstrated by expiratory flow rates (the ratio of forced vital capacity at one second to the total forced vital capacity [FEV1/FVC]), and the forced expiratory flow for the midportion of the forced vital capacity (FEF25–75%). A significant fall in Rawoccurred in 129 patients, 46 of whom had a significant increase in vital capacity (mean of + 465 ml ± 43, P < 0.001) and a fall in FRCB(mean of −763 ml ± 78 P < 0.001) with no change in FEV1/FVC% or FEF25–75%. We interpret these data to indicate that improvement in static lung volumes can reflect bronchodilation in the absence of improved expiratory flow.

Sixteen patients with suspected reversible airway obstruction who had previously demonstrated an increase in specific airway conductance after isoproterenol, but who had not demonstrated an increase in forced expiratory flow were studied using a measurement of submaximal flow. Flow during tidal breathing ( V˙TV) was measured spirometrically, and V˙TVincreased in all 16 patients from a value of 0.61 L/sec before isoproterenol to 0.80 L/sec after isoproterenol. In addition, each of these 16 patients experienced a significant increase in vital capacity and a significant decompression of functional residual capacity after isoproterenol. If plethysmography is not available, the measurement of V˙TVmay provide evidence of bronchodilatation. The mechanism responsible for the dichotomy between maximal and submaximal flow is the compression of airways by high positive pleural pressure which is present during maximal, but not submaximal maneuvers.

The regional distribution of pulmonary ventilation is nonuniform in health and disease. Single and multiple breath techniques have been developed to assess this nonuniformity. Limitations of these expired gas techniques include: identification of only several of the component washout exponentials and preferential representation in this single curve of the better ventilated spaces. In ten normal persons and eight patients we assessed the washout of ventilation by three simultaneous techniques and obtained three clearance curves: nitrogen washout with 100 percent O2; washout of 133Xe at the mouth with 100 percent O2; clearance of 133Xe from the patients' lung fields. A scintillation camera/computer system was utilized to provide clearance curves for 133Xe from selected zones of interest varying from both lungs to sublobar regions. In normal persons all three curves were superimposable. In patients with diffuse lung disease the expired curve for N2and 133Xe at the mouth were abnormal but superimposable, while the xenon clearance over the lung fields revealed slower and more abnormal clearances. These latter curves provided an appreciation of the presence, localization, and extent of both slow and fast spaces.