Christoph Wyser

Prediction of functional reserves after lung resection: comparison between quantitative computed tomography, scintigraphy, and anatomy.

Background and Objectives: We prospectively compared five techniques to estimate predicted postoperative function (ppo F) after lung resection: recently proposed quantitative CT scans (CT), perfusion scans (Q), and three anatomical formulae based on the number of segments (S), functional segments (FS), and subsegments (SS) to be removed. Methods: Four parameters were assessed: FEV1, FVC, DLCO and VO2max, measured preoperatively and 6 months postoperatively in 44 patients undergoing pulmonary resection, comparing their ppo value to the postoperatively measured value. Results: The correlations (r) obtained with the five methods were for CT: FEV1 = 0.91, FVC = 0.86, DLCO = 0.84, VO2max = 0.77; for Q: 0.92, 0.90, 0.85, 0.85; for S: 0.88, 0.86, 0.84, 0.75; for FS: 0.88, 0.85, 0.85, 0.75, and for SS: 0.88, 0.86, 0.85, 0.75, respectively. The mean difference between ppo values and postoperatively measured values was smallest for Q estimates and largest for anatomical estimates using S. Stratification of the extent of resection into lobectomy (n = 30) + wedge resections (n = 4) versus pneumonectomy (n = 10) resulted in persistently high correlations for Q and CT estimates, whereas all anatomical correlations were lower after pneumonectomy. Conclusions: We conclude that both Q- and CT-based predictions of postoperative cardiopulmonary function are useful irrespective of the extent of resection, but Q-based results were the most accurate. Anatomically based calculations of ppo F using FS or SS should be reserved for resections not exceeding one lobe.

Evaluation of High-Risk Lung Resection Candidates: Pulmonary Haemodynamics versus Exercise Testing

We compared the value of exercise testing and measurement of pulmonary haemodynamics (PH) in the pre-operative assessment of 5 patients (mean age: 64 years, 3 men) with clinical stage I or II bronchogenic carcinoma and severe chronic obstructive pulmonary disease. They were considered at high risk due to poor pulmonary function tests (PFT); (one or more of the following): (1) radionuclide calculated postlobectomy FEV1 < 30% predicted, (2) diffusion capacity or transfer factor < 60% predicted, combined with a fall in PaO2 on maximal exercise of > 5 mm Hg, (3) a PaCO2 at rest of > 45 mm Hg. Maximal oxygen uptake (VO2max) during symptom-limited cycle ergometry and PH were measured in these 5 patients. They were considered eligible for lobectomy if they fulfilled at least one of the two criteria: (1) mean pulmonary artery pressure (PAP) of < 35 mm Hg and pulmonary vascular resistance of < 190 dyn.s.cm-5 at moderate exercise (40 W), (2) a VO2max of > or = 15 ml/kg/min. Six months postoperatively PFT and VO2max were measured again. PAP40W was 21, 38, 38, 46 and 52 mm Hg, respectively, which would have excluded 4/5 patients from surgery. VO2max was 21.7, 14.9, 13.4, 19.2 and 18.6 ml/kg/min, respectively, which would have excluded 2/5 patients. Expressed in percent predicted, however, VO2max was > or = 69% in all 5 patients, indicating only mild impairment of exercise capacity in the 2 patients with < 15 ml/kg/min VO2max. Therefore all 5 patients were offered surgery and underwent lobectomy. Apart from 1 prolonged air leak no complications occurred, the mean hospital stay was 16 days (13-21).(ABSTRACT TRUNCATED AT 250 WORDS)

Pulmonary Mucosa-Associated Lymphoid Tissue Lymphoma in a Patient with Common Variable Immunodeficiency Syndrome

Common variable immunodeficiency syndrome (CVID) is a primary immunodeficiency typically presenting with recurrent sinopulmonary infections. Non-Hodgkin’s lymphoma and other secondary cancers are typical late complications of CVID. We report on a patient suffering from CVID with a history of recurrent sinopulmonary infections, interstitial pulmonary changes and hepatic granulomas. Despite treatment with intravenous immunoglobulin followed by a reduction in the number of pulmonary infections, reticular and nodular lung changes progressed. Video-assisted thoracoscopic lung biopsy showed a low-grade B cell lymphoma of the mucosa-associated lymphoid tissue (MALT) of the bronchus without evidence of pulmonary infection. In conclusion, MALT lymphoma of the lung should be considered in the differential diagnosis of progressive lung disease in CVID.