Reduced carbon monoxide transfer factor (TLCO) in human immunodeficiency virus type I (HIV-I) infection as a predictor for faster progression to AIDS.

BACKGROUND--In addition to the acute fall in carbon monoxide transfer factor (TLCO) associated with Pneumocystis carinii pneumonia (PCP) or other opportunistic lung infections, reduced TLCO occurs in HIV-I seropositive individuals without active pulmonary disease. Abnormal TLCO, in the absence of lung disease, may be a surrogate marker of HIV-I induced immunosuppression and, therefore, a predictor for a more rapid progression to AIDS. METHODS--Eighty four individuals with AIDS, who had regular pulmonary function tests before the diagnosis of AIDS was made, were identified from a cohort of patients with HIV-I infection. None had evidence of active pulmonary disease at the time of initial pulmonary function testing. The relation between the time taken to progress to AIDS and initial pulmonary function tests was examined with life table survival analysis. RESULTS--Patients with a TLCO value of < 80% of predicted normal (n = 46) progressed significantly faster to AIDS, with a median time of 8.0 months compared with 16.5 months for those with a TLCO value of > or = 80% (n = 38). When stratified by AIDS defining diagnosis (PCP or non-PCP), median time to PCP was also significantly related to initial TLCO values (TLCO of < 80% = 9.0 months, TLCO of > or = 80% = 19.0 months). Reductions in other measurements of lung function (FEV1, FVC, KCO) were not temporally associated with the development of AIDS. CONCLUSIONS--HIV-I seropositive individuals with TLCO values of < 80% predicted and no evidence of lung disease progress more rapidly to AIDS than those with TLCO values of > or = 80%.     

Bronchopulmonary Kaposi''s sarcoma in patients with AIDS.

BACKGROUND: Kaposi's sarcoma in HIV antibody positive patients may affect the lungs. This study describes the presentation, chest radiographic appearances, and pulmonary function test abnormalities in patients with AIDS who had tracheobronchial Kaposi's sarcoma. METHODS AND RESULTS: Twenty nine (8%) of 361 consecutive HIV antibody positive patients undergoing bronchoscopy for respiratory symptoms had tracheobronchial Kaposi's sarcoma. Eight patients had intercurrent infections and one had previously received chemotherapy for cutaneous Kaposi's sarcoma; these patients were excluded. Seven of the remaining 20 patients had localised Kaposi's sarcoma (lesions confined to the trachea or the subsegments of one lobe) and 13 had widespread Kaposi's sarcoma (affecting the trachea and one lobe or the subsegments of more than one lobe); 19 patients also had cutaneous and palatal Kaposi's sarcoma. Seven patients, four with widespread disease, had a normal radiograph. All patients had reduced transfer factor (TLCO) and transfer coefficient (KCO) but only those with widespread disease had reductions in forced expiratory volume in one second (FEV1), forced vital capacity (FVC), and peak expiratory flow (PEF). Follow up pulmonary function testing in seven patients (median three months later) showed further reductions in TLCO. All four patients who received no treatment had progressive radiographic abnormalities; bronchoscopy in two patients showed progressive tracheobronchial disease, and two patients had further reductions in FEV1 and FVC. In three patients treated with chemotherapy palliation of symptoms was achieved but two had further reductions in FEV1 and FVC and the radiograph deteriorated. Bronchoscopy showed regression of disease in only one patient. CONCLUSION: Pulmonary Kaposi's sarcoma produces abnormalities of TLCO even in patients with localised disease; airflow obstruction may occur in patients with widespread disease. Bronchoscopic reassessment of the extent of disease may not accurately reflect response to chemotherapy.     

Pulmonary function in advanced pulmonary hypertension.

Pulmonary mechanical function and gas exchange were studied in 33 patients with advanced pulmonary vascular disease, resulting from primary pulmonary hypertension in 18 cases and from Eisenmenger physiology in 15 cases. Evidence of airway obstruction was found in most patients. In addition, mean total lung capacity (TLC) was only 81.5% of predicted and 27% of our subjects had values of TLC less than one standard deviation below the mean predicted value. The mean value for transfer factor (TLCO) was 71.8% of predicted and appreciable arterial hypoxaemia was present, which was disproportionate to the mild derangements in pulmonary mechanics. Patients with Eisenmenger physiology had significantly lower values of arterial oxygen tension (PaO2) (p less than 0.05) and of maximum mid expiratory flow (p less than 0.05) and significantly higher pulmonary arterial pressure (p less than 0.05) than those with primary pulmonary hypertension, but no other variables were significantly different between the two subpopulations. It is concluded that advanced pulmonary vascular disease in patients with primary pulmonary hypertension and Eisenmenger physiology is associated not only with severe hypoxaemia but also with altered pulmonary mechanical function.     

Pulmonary capillary blood volume in patients with probable pulmonary Kaposi's sarcoma.

BACKGROUND: An increase in pulmonary capillary blood volume secondary to angiogenesis has been described in Kaposi's sarcoma. The value of the pulmonary capillary blood volume as an early marker of pulmonary Kaposi's sarcoma was evaluated. METHODS: In a prospective study 45 HIV positive patients (nine asymptomatic for Kaposi's sarcoma, 29 with cutaneous or mucocutaneous Kaposi's sarcoma, and seven with pulmonary Kaposi's sarcoma), underwent pulmonary function tests and determination of transfer capacity for carbon monoxide (TLCO) with its components, pulmonary capillary volume and membrane factor. RESULTS: Total lung capacity (TLC), TLCO, and its components were similar in the three groups. TLCO was normal in patients with pulmonary Kaposi's sarcoma and no changes in membrane factor or pulmonary capillary volume were observed. CONCLUSION: Pulmonary function tests and pulmonary capillary volume alone are not useful for identifying patients with pulmonary Kaposi's sarcoma.     

Bronchial responsiveness, lung mechanics, gas transfer, and corticosteroid response in patients with chronic airflow obstruction.

Thirty patients with stable chronic airflow obstruction receiving regular bronchodilator treatment were studied to determine whether the level of bronchial responsiveness, transfer factor for carbon monoxide (TLCO), or the mechanical properties of the lung predicted a bronchodilator response to oral corticosteroid treatment. Before treatment mean (SD) FEV1 was 48% (16%) of the predicted value (% pred); the geometric mean concentration of methacholine required to produce a 20% fall in FEV1 (PC20) was 0.44 (range 0.07-3.32) mg/ml; and TLCO was 59% (21%) predicted. The exponential constant (k) defining the shape of the static volume-pressure curve was 146% (66%) predicted and pulmonary conductance relative to predicted lung volume at a transpulmonary pressure of 5 cm H2O (sGL5) was 72% (37%) predicted. After prednisolone treatment (0.6 mg kg-1 day-1 for two weeks) FEV1 increased by 8% (19%) (p less than 0.05) and daily mean peak flow (PEF) by 3% (10%) (p less than 0.01) over pretreatment values. Three patients had an increase in FEV1 of more than 30%, two of whom had sputum eosinophilia (p less than 0.05). The three were among the 13 patients with a reduced sGL5. The increase in FEV1 did not correlate with initial PC20 (r = 0.16), k (r = -0.12), or TLCO (r = -0.14). Thus measurements of bronchial responsiveness, lung distensibility, and TLCO did not predict corticosteroid response in patients with stable chronic airflow obstruction. Patients with sputum eosinophilia or reduced pulmonary conductance may be more likely to respond.     

Relation of lung function, maximal inspiratory pressure, dyspnoea, and quality of life with exercise capacity in patients with chronic obstructive pulmonary disease.

BACKGROUND--Several studies have shown that both objective and subjective measurements are related to exercise capacity in patients with chronic obstructive pulmonary disease (COPD). In this study the relative contribution of lung function, maximal inspiratory pressure, dyspnoea, and quality of life to the performance in a walking distance test and a bicycle ergometer test was investigated. METHODS--Static lung volumes, forced expiratory volume in one second (FEV1), inspiratory slow vital capacity (IVC), transfer factor for carbon monoxide (TLCO) divided by the alveolar volume (TLCO/VA), static compliance (Cst), and maximal inspiratory peak pressure (PImaxPOES) were measured in 40 patients with COPD with severe airways obstruction (mean FEV1 44% predicted, mean FEV1/IVC 37% predicted). Quality of life was assessed by the Chronic Respiratory Questionnaire (CRQ) and dyspnoea by the Borg category scale. Exercise capacity was measured by both a six minute walking distance (test) and a maximal work load of the bicycle ergometer test (Wmax). RESULTS--Spirometric values and maximal inspiratory pressure were modestly correlated with both the six minute walking test and Wmax, r values ranging from 0.50 to 0.58. The TLCO was strongly correlated with the six minute walking test (r = 0.62) and with Wmax (r = 0.78). Quality of life showed no correlation with exercise capacity, while there was a correlation between dyspnoea and the six minute walking test (r = -0.41). Backward linear regression analysis selected TLCO and PImaxPOES as the most significant determinants for exercise performance. They explained 54% and 69% of the variance in the six minute walking test and Wmax, respectively. CONCLUSIONS--The results show that exercise capacity in patients with COPD with severe airways obstruction is more strongly related to inspiratory muscle strength and lung function than to dyspnoea and quality of life. The significant correlation between dyspnoea and the six minute walking test suggests that subjective variables are more strongly related to walking tests than to bicycle ergometer tests.     

Pulmonary function in chronic heart failure. Changes after heart transplantation.

To investigate the impact of chronic heart failure on pulmonary function in heart transplant recipients, pulmonary function was evaluated in 41 consecutive patients (mean age 43 years, range 15-57 years) before and 6 months after successful heart transplantation. The pulmonary function tests included measurements of forced vital capacity [FVC], forced expiratory volume in 1.s [FEV1], FEV1/FVC ratio, total lung capacity [TLC], and diffusion capacity for carbon monoxide [TLCO] and KCO [TLCO per l alveolar volume]. Compared to pretransplant values, spirometry after transplantation revealed modest improvements in FVC (from 77 +/- 16 to 88 +/- 21% of predicted [%pred]; p < 0.001) and FEV1 (from 75 +/- 16 to 85 +/- 22%pred; p < 0.001), whereas the FEV1/FVC ratio was unchanged (81% +/- 11 and 80% +/- 10; p = NS). A slight but statistically significant increase in TLC (from 78 +/- 15 to 86 +/- 18%pred, p < 0.001) was also observed. Prior to transplantation the mean TLCO was 76 +/- 17%pred; 7 of the patients had a TLCO below 60%pred (mean 51% pred). In 33 of the 41 patients a reduction in TLCO was observed after transplantation; for all 41 patients the mean fall in TLCO was 14% of the predicted value (SD 12%pred) (p < 0.0001). Likewise, a significant reduction in KCO was noted (p < 0.0001). Multiple regression analysis revealed that high pretransplant TLCO %pred (p = 0.02) and FVC %pred (p = 0.04) were associated with a less favorable outcome concerning posttransplant TLCO %pred. Although normalization of FEV1, FVC and TLC can be anticipated after correction of severe chronic left ventricular failure by heart transplantation, the pronounced concomitant decline in diffusion capacity observed in this study may be explained by underlying pulmonary disease caused by factors other than long-standing heart failure. Our findings support the notion that pulmonary function abnormalities attributable to chronic heart failure should not preclude consideration for heart transplantation.     

AIDS and the lung. Introduction.

Damage to the immune system induced by the human immunodeficiency virus (HIV) leads to a spectrum of opportunistic infections of which the lung is the most common site. In Europe and North America, pneumocystis carinii pneumonia is the presenting symptom in 64% of cases of acquired immunodeficiency syndrome (AIDS) and occurs at some point in 80% of AIDS victims. This infection is less common in Africa, where tuberculosis is the predominant opportunistic infection. Other AIDS-related lung infections that are gaining in prevalence include pneumonia due to pyogenic bacteria, pulmonary infection with Mycobacterium tuberculosis, and lymphoid interstitial pneumonitis. In addition, there is evidence that the lung may be extensively involved in Kaposi's sarcoma. Given the importance of the lung as a site for AIDS-related opportunistic infections, respiratory physicians will be required to become more involved in the diagnosis and management of AIDS cases.     

Impact of severe acute respiratory syndrome (SARS) on pulmonary function, functional capacity and quality of life in a cohort of survivors

OBJECTIVE: To examine the impact of severe acute respiratory syndrome (SARS) on pulmonary function, exercise capacity, and health-related quality of life (HRQoL) among survivors. METHODS: 110 survivors with confirmed SARS were evaluated at the Prince of Wales Hospital, HK at the end of 3 and 6 months after symptom onset. The assessment included lung volumes (TLC, VC, RV, FRC), spirometry (FVC, FEV1), carbon monoxide transfer factor (TLCO adjusted for haemoglobin), inspiratory and expiratory respiratory muscle strength (Pimax and Pemax), 6 minute walk distance (6MWD), chest radiographs, and HRQoL by SF-36 questionnaire. RESULTS: There were 44 men and 66 women with a mean (SD) age of 35.6 (9.8) years and body mass index of 23.1 (4.8) kg/m2. Seventy (64%) were healthcare workers. At 6 months 33 subjects (30%) had abnormal chest radiographs; four (3.6%), eight (7.4%), and 17 (15.5%) patients had FVC, TLC, and TLCO below 80% of predicted values; and 15 (13.9%) and 24 (22.2%) had Pimax and Pemax values below 80 cm H2O, respectively. The 6MWD increased from a mean (SD) of 464 (83) m at 3 months to 502 (95) m (95% CI 22 to 54 m, p<0.001), but the results were lower than normal controls in the same age groups. There was impairment of HRQoL at 6 months. Patients who required ICU admission (n = 31) had significantly lower FVC, TLC, and TLCO than those who did not. CONCLUSION: The exercise capacity and health status of SARS survivors was considerably lower than that of a normal population at 6 months. Significant impairment in surface area for gas exchange was noted in 15.5% of survivors. The functional disability appears out of proportion to the degree of lung function impairment and may be related to additional factors such as muscle deconditioning and steroid myopathy.     

Pulmonary 99mTc-DTPA aerosol clearance and survival in usual interstitial pneumonia (UIP)

BACKGROUND: Clearance of inhaled technetium 99m-labelled diethylenetriamine penta-acetic acid ((99m)Tc-DTPA) from the lungs is a potential indicator of disease progression in patients with idiopathic pulmonary fibrosis (IPF). METHODS: We prospectively analysed the usefulness of this technique for predicting survival in 106 non-smoking patients with usual interstitial pneumonia (UIP) pattern IPF diagnosed by high resolution CT (HRCT) scanning or histological examination (M/F 65/41, mean (SD) age 61 (11) years). DTPA clearance was analysed according to both mono-exponential and bi-exponential models. Half times for the fast (t(0.5)F) and slow (t(0.5)S) components of clearance, the percentage contribution of the fast component (fF), and half time for mono-exponential approximation to the early part of the clearance curve (t(0.5)) were calculated. RESULTS: The patients had substantially faster t(0.5) (mean 23.9 (9.6) minutes) than normal values (>45 minutes). Thirty seven patients (35%) died during follow up (median 15 months). Univariate Cox regression analysis identified significant predictors of survival as age, forced expiratory volume in 1 second (FEV(1)), forced vital capacity (FVC), total lung capacity (TLC), % predicted TLC, carbon monoxide transfer factor (TLCO), % predicted TLCO, arterial oxygen tension (PaO(2)), oxygen saturation, t(0.5)F, and HRCT fibrosis score. Multiple stepwise Cox regression analysis identified t(0.5)F (p=0.03, hazard ratio 0.747, 95% CI 0.578 to 0.964), % predicted TLC (p=0.02, hazard ratio 0.976, 95% CI 0.956 to 0.995), % predicted TLCO (p=0.003, hazard ratio 0.960, 95% CI 0.935 to 0.986), and age (p=0.003, hazard ratio 1.062, 95% CI 1.021 to 1.104) as independent predictors of survival. CONCLUSION: These data suggest that (99m)Tc-DTPA clearance t(0.5)F measurement may predict survival in patients with UIP pattern IPF.     

Interrelationship between lung volume, expiratory flow, and lung transfer factor in fibrosing alveolitis.

Fifty patients with fibrosing alveolitis studied on 104 occasions exhibited significant direct correlations between vital capacity (VC), maximum mid-expiratory flow rate (MMFR), and transfer factor for carbon monoxide (TLCO). Forced expired volume in the first second (FEV1)/VC ratio bore a weak negative correlation with VC. Peak expiratory flow, MMFR, and maximum flow rates at 50% and 25% of VC were often reduced in patients with severe grades of pulmonary dysfunction. It appears that as the severity of the fibrotic process increases, the lung volumes shrink and the transfer factor for CO decreases. The total lung capacity decreases predominantly on account of reduction in VC. With a decrease in lung volume the MMFR also falls. Decrease in flow rates at low lung volumes is greater as compared to the fall in peak flow. The expiratory flow rates however were normal or even increased when related to absolute lung volume. Some patients exhibit disproportionate expiratory slowing as evidenced by a decrease in MMFR which is out of proportion to the reduction in VC. These patients also have a reduced FEV1/VC ratio. These changes are probably the consequence of associated peripheral airway narrowing.     

Comparison of the single breath with the intrabreath method for the measurement of the carbon monoxide transfer factor in subjects with and without airways obstruction.

BACKGROUND--Measurement of the carbon monoxide transfer factor (TLCO) has traditionally been performed using the single breath method but recently the intrabreath method has been developed. The aim of this study was to compare the two methods in the clinical evaluation of patients with obstructive and non-obstructive pulmonary disorders. METHODS--Measurements of TLCO with the intrabreath method were carried out on a study sample composed of 50 patients with non-obstructive disorders and 50 with airways obstruction (FEV1/FVC < 70%) either before or after a single breath measurement of the TLCO had been performed. The method involves the continuous analysis of a single slow expirate using a computerised rapid multigas infrared analyser. TLCO, alveolar volume (VA), TLCO/VA, and inspired vital capacity (IVC) values were obtained for both groups by both methods. RESULTS--When measured with the intrabreath method the group with airways obstruction showed lower TLCO and TLCO/VA values than the non-obstructive group. VA was higher in both patient groups when measured with the intrabreath technique. The same test also showed higher TLCO values with the intrabreath method in the group with non-obstructive disorders and lower TLCO/VA values with the intrabreath method in those with airways obstruction. The corresponding parameters obtained by the two methods correlated closely, with no correlation between the magnitude of the differences with the magnitude of the readings. An index of gas mixing indicated a better distribution of the inspired air for the intrabreath method than for the single breath method. The VA values obtained with the intrabreath method showed a closer agreement to the actual total lung capacities measured by body plethysmography. CONCLUSION--The intrabreath method of determining TLCO is comparable to the traditional single breath method. Measurement of alveolar volume by the intrabreath method approximates more closely to total lung capacity, even in subjects with airways obstruction.     

Fibreoptic bronchoscopy in diagnosis of bronchopulmonary Kaposi''s sarcoma.

Kaposi's sarcoma of the lung patients with the acquired immune deficiency syndrome is often indistinguishable by clinical and radiographic criteria from opportunistic pneumonia. Pulmonary Kaposi's sarcoma and pneumonia may frequently be present in the same patient. Previous observers have commented on the repeated failure to establish a diagnosis of Kaposi's sarcoma of the lung by fibreoptic bronchoscopy. Thirteen fibreoptic bronchoscopies were performed in a series of 11 patients with thoracic manifestations of AIDS and Kaposi's sarcoma was identified in transbronchial or bronchial biopsy specimens in four patients. This diagnostic yield is comparable to that obtained only by open lung biopsy procedures in previous reports. Fibreoptic bronchoscopy may contribute to the correct management of the patient and facilitate an accurate prognosis by differentiating between opportunistic pneumonia and pulmonary Kaposi's sarcoma.     

Can lung function measurements be used to predict which patients will be at risk of developing interstitial pneumonitis after bone marrow transplantation?

BACKGROUND: Lung function often deteriorates after bone marrow transplantation for haematological malignancies. Whether pulmonary function measurements are useful for monitoring patients' progress after transplantation and for alerting clinicians to the development of pneumonitis is uncertain. METHODS: Serial pulmonary function measurements were made in 39 patients with a haematological malignancy, and the values from 18 recipients of T cell depleted allogeneic (n = 17) or autologous (n = 1) bone marrow transplants who developed interstitial pneumonitis were compared retrospectively with values from 21 recipients of allogeneic (n = 17) or autologous (n = 4) transplants who did not develop pneumonitis. Lung function was measured at the onset of a further 18 episodes of pneumonitis. RESULTS: Measurements made before transplantation showed no difference in forced expiratory volume in one second (FEV1), transfer factor for carbon monoxide (TLCO), or total lung capacity between the two groups, but the forced vital capacity (FVC) was slightly higher in those who developed pneumonitis (mean (SD)% predicted 104 (12)) than in those who did not (93 (17%)). Six weeks and three months after transplantation all pulmonary function measurements had fallen slightly in both groups but TLCO had fallen considerably more in those who later developed pneumonitis, being 71% (SD 11%) and 77% (7%) of pretransplant values in patients who later developed pneumonitis compared with 109% (38%) and 96% (26%) in those who did not. All lung function measurements were significantly lower at the onset of pneumonitis than three months after transplantation, even in patients with no abnormal signs and a normal chest radiograph. CONCLUSIONS: Serial measurements of gas transfer before and after bone marrow transplantation may be useful for predicting which patients will be at risk of developing pneumonitis and may help to diagnose pneumonitis in breathless patients with no abnormal signs.     

Carbon monoxide diffusing capacity in polycythaemia rubra vera.

The diffusing capacity of the lung, or transfer factor, for carbon monoxide (TLCO) was measured in 12 patients with polycythaemia rubra vera. This was significantly raised (mean 152% predicted, SEM +/- 14%) and remained so even after correction to a standard haemoglobin concentration of 14 . 6 g/dl (mean 139% predicted, SEM +/- 13%). Serial measurements of TLCO on two patients after treatment of polycythaemia rubra vera showed a greater fall in relation to haemoglobin concentration than would have been predicted on theoretical grounds if the increases in TLCO had been due entirely to the increased haemoglobin concentration. The pulmonary capillary blood volume (estimated from TLCO) also fell in these two patients after treatment. There was a strong correlation between TLCO and the technetium-99m-labelled red cell volume for the seven men (r = 0 . 92; p less than 0 . 01) and five women (r = 0 . 99; p less than 0 . 001) when studies were performed on the same day. In patients with polycythaemia rubra vera who have no evidence of coexistent pulmonary disease the pulmonary capillary bed appears to share in the expansion of the body blood volume. The single-breath TLCO test may act as a convenient and simple monitor for the response of the disease to treatment.     

Airways obstruction associated with graft versus host disease after bone marrow transplantation.

Eight patients, five with chronic granulocytic leukaemia and three with severe aplastic anaemia, developed moderately severe airflow obstruction after allogeneic bone marrow transplantation. All eight had clinically and radiologically normal lungs before undergoing transplantation. Treatment in the patients with chronic granulocytic leukaemia before transplantation included high dose total body irradiation. All eight patients developed acute and chronic graft versus host disease after transplantation. The pulmonary syndrome consisted of cough, dyspnoea, and wheezing beginning six to 20 weeks after transplantation, with ratios of forced expiratory volume in one second (FEV1) to vital capacity (VC) falling to 60% or less of predicted values. The three patients with severe aplastic anaemia had relatively mild graft versus host disease and acute chest infection may have initiated or contributed to their airways obstruction, which subsequently resolved. The five patients with chronic granulocytic leukaemia had more severe graft versus host disease and more progressive respiratory problems; two died and three continued to have persistent airflow obstruction 11, 15, and 20 months after transplantation. None of those with chronic granulocytic leukaemia improved. Transfer factor (TLCO) was reduced in all patients after bone marrow transfer and did not improve; in the patients with chronic granulocytic leukaemia the reduction in TLCO preceded the fall in FEV1/VC ratio. Open lung biopsy in one of the patients with chronic granulocytic leukaemia showed obliterative bronchiolitis with lymphocytic infiltration consistent with graft versus host disease. Bronchodilators were of no benefit in the management of these patients, but prompt treatment of infection and early use of corticosteroids may have contributed to the improvement seen in the patients with severe aplastic anaemia.     

Abnormal lung function associated with asbestos disease of the pleura, the lung, and both: a comparative analysis.

The impairment of lung function associated with different types of asbestos related disease was examined in 1298 men. The 310 men with circumscribed pleural lesions (plaques) or diffuse pleural thickening without asbestosis were compared with 596 men with asbestosis only and with 322 men with pleural abnormalities and asbestosis, as classified from chest radiographs by ILO pneumoconiosis criteria. Spirometric indices and total lung capacity (TLC; determined by planimetry) were measured and expressed as percentages of predicted values. Non-smoking men with pleural disease only had reduced values of mid and terminal expiratory flows (80.6 and 69.9% predicted) and a reduced FEV1 (89% predicted) with a forced vital capacity (FVC) of 94% predicted. TLC was 104% predicted. Thus they had airways obstruction with-out restriction. Non-smoking men with pulmonary asbestosis (ILO profusion of opacities mostly 1/0 and 1/1) had pulmonary function similar to that of men with pleural disease. FEV1 and FVC and flow rates at other lung volumes were lower in smokers with asbestosis (after adjustment for duration of smoking) than in the non-smokers with asbestosis. Airflow limitation was worse in the men with both pleural abnormalities and pulmonary asbestosis with lower values for mid expiratory flow, FEV1 and FVC (but not TLC) than those with either abnormality alone, in both non-smokers and current smokers. Men with diffuse pleural thickening that included the costophrenic angles had more airways obstruction and air trapping and lower FVC values than those with circumscribed pleural disease.     

Pulmonary function after bone marrow transplantation for chronic myeloid leukaemia.

Pulmonary function was measured before and at intervals after treatment in 44 patients who received a bone marrow transplant for chronic myeloid leukaemia in the chronic phase. All patients were treated with cytotoxic drugs, total body irradiation, and post-graft immunosuppression. Thirty four patients surviving for 12 months were followed at three monthly intervals and 16 patients for 24 months. Fifteen patients received unmanipulated donor marrow cells and 29 patients received donor marrow cells depleted of lymphocytes ex vivo with the monoclonal antibody Campath-1. The 21 patients treated early in this study received 10 Gy of total body irradiation whereas the 23 patients treated more recently, who were all T lymphocyte depleted, received 12 Gy. Pretransplant lung function for the group was normal and was similar in survivors (n = 34) and nonsurvivors (n = 10), and in smokers (n = 8) and non-smokers (n = 36). (Carbon monoxide transfer factor--TLCO) was under 75% of predicted normal in nine patients before transplantation. TLCO, carbon monoxide transfer coefficient (KCO), FEV1, and vital capacity (VC) values were lower 6 and 12 months after bone marrow transplant than initially. The greatest decline was in TLCO, from an initial value of 89% to 66% at 6 and 70% at 12 months. The 16 longer term survivors showed significant recovery of function between 6 and 24 months after bone marrow transplant for TLCO, KCO, and VC, the increase ranging from 6.3% to 7.3% predicted. Airflow obstruction (FEV1/VC ratio less than 70%) developed in one patient. The major factors associated with deterioration in pulmonary function at 6 and 12 months after transplantation in the 34 survivors (stepwise multiple regression analysis) were (a) transplantation with T cell depleted donor marrow (p less than 0.005) and higher total body irradiation dose (p less than 0.02) with a fall in KCO and an increase in the FEV1/VC ratio; (b) chronic graft versus host disease with a fall in VC (p less than 0.01); and less fall in KCO (p less than 0.01); and (c) acute graft versus host disease with a fall in FEV1 (p less than 0.01). It is considered that most patients who survive the short term risks of bone marrow transplant have only minor long term impairment of pulmonary function.     

Sequelae of the adult respiratory distress syndrome.

Most survivors of ARDS have persistent mild reductions of TLCO even as long as a year after their episode. The lung volumes and flows return to normal in most instances, although a subset of patients will have persistent impairment. Both obstructive and restrictive deficits may be seen. This group may be predicted by the degree of acute lung injury assessed by the level of FIO2, PEEP, and gas exchange abnormality that exists in the first few days. In the first year after ARDS most physiological abnormalities will improve, but if deficits persist at one year further improvement is unlikely. Although many patients report dyspnoea following ARDS, the symptom does not correlate with abnormalities of pulmonary function. The possibility that conventional management may augment the degree of acute injury and worsen outcome must be considered. The effects of chronic hyperoxia in humans with acute lung injury or those of high levels of PEEP compared with low levels are not known. Exploring new ventilator management strategies while we await more specific treatment directed at the primary problem of acute lung inflammation will hopefully reduce acute mortality as well as acute and chronic morbidity.     

青少年特发性脊柱侧凸患者术前肺功能影响因素分析及临床意义

目的 分析影响青少年特发性脊柱侧凸患者术前肺功能的相关影像学参数及其临床意义.方法 回顾性研究2009年7月～2012年8月本院收治的青少年特发性脊柱侧凸患者24例,术前肺功能检查、胸部CT扫描资料完整.分析肺功能结果与站立位全长X线片Cobb角、顶椎偏移、椎体旋转分度（Nash/Moe法）、顶椎肋椎角差值、矢状位T5-12后凸角和胸段累及椎体数目之间相关性.结果 患者年龄平均14.8岁,Cobb角平均52.8°;主弯Cobb角与术前肺活量占预计值百分比、第1秒最大呼气容积占预计值百分比、用力肺活量占预计值百分比、最大通气量占预计值百分比、肺总量占预计值百分比、一氧化碳弥散量占预计值百分比和一氧化碳弥散量呈负相关;顶椎偏移与肺总量占预计值百分比、一氧化碳弥散量占预计值百分比及一氧化碳弥散量呈明显负相关;站立位顶椎凸凹侧肋椎角差值分别与肺总量占预计值百分比、肺总量、一氧化碳弥散量占预计值百分比和一氧化碳弥散量呈负相关;Bending位顶椎凸凹侧肋椎角差值与肺总量、一氧化碳弥散量呈负相关;胸段累及椎体数≥7个组患者50％肺活量时最大呼气流量、75％肺活量时最大呼气流量、最大用力呼气中段流速占预计值百分比、最大通气量占预计值百分比及一氧化碳弥散量占预计值百分比数值,比胸段累及椎体数＜7个组患者有减少（P＜0.05）.结论 术前站立位主弯Cobb角愈大,主弯顶椎偏移增大,站立位以及Bending位顶椎凸凹侧肋椎角差值增加,肺功能下降.近胸弯≥30°组较之＜30°组,胸段累及椎体数≥7个组较之＜7个组,肺功能数值下降.