Effect of simvastatin on micropulmonary red cell mass in patients with hyperlipoproteinemia.

The purpose of this study was to compare the macrocirculatory and microcirculatory effects of simvastatin in hyperlipemic patients. In vitro measurements of lipoprotein levels and macrocirculatory hemorheology were complemented by in vivo measurements of the pulmonary capillary red cell volume (RCVpc) before and after 6 weeks of treatment with 40 mg of simvastatin daily in 30 male patients with hyperlipoproteinemia type IIa. RCVpc was assessed from the vascular component of the lung diffusing capacity for carbon monoxide, using the modification of the Roughton-Forster's method. RCVpc was increased in patients (60.9+/-9 versus 40+/-9 ml in healthy controls) and it decreased to 47+/-6 ml after treatment (P=5x10(-11)). The decreases in RCVpc correlated to concomitant decreases in peripheral hematocrit (R=0.68) and serum total cholesterol (-34% on average; R=0.59). Membrane diffusing capacity was normal in patients and not affected by the therapy; suggesting that increased RCVpc was due to increased micropulmonary hematocrit. Thus, it appears that viscosity in microcirculation is greatly increased in hyperlipemic patients and that simvastatin is able to normalize it. Since microcirculatory conditions can only partly be inferred from in vitro measurements the use of lung diffusional parameters was advocated, which enable in vivo assessment of hemorheology in microcirculation.

Laparoscopic and laparotomic cholecystectomy: a randomized trial comparing postoperative respiratory function.

BACKGROUND: The fact that pulmonary complications occur in 20-60% of the patients subjected to abdominal operations clearly indicates that the lungs are the most endangered organ during the postoperative period. OBJECTIVE: The aim of this study was to demonstrate the impact of cholecystectomy on postoperative respiratory disturbances by comparing the laparotomic cholecystectomy with laparoscopic gallbladder removal. PATIENTS AND METHODS: A hundred cholecystectomized patients were included in the prospective randomized clinical trial. Half of the patients were operated on by the laparotomic procedure, whereas the other half underwent laparoscopic cholecystectomy. Spirometric parameters, arterial blood gases, and acid-base balance were determined before the operation, and at 6, 24, 72 and 144 h postoperatively. Abdominal distension was assessed by auscultating intestinal peristaltics, abdominal circumference measurement, and time interval to restitution of defecation. RESULTS: Six hours postoperatively, the values of ventilation parameters decreased on average by 40-50% from the baseline preoperative values in both groups of patients. The group of patients submitted to laparotomic cholecystectomy had significantly lower spirometric values and slower recovery of the ventilation parameters than the laparoscopic cholecystectomy group. Abdominal circumference was significantly greater and the time needed for restitution of peristaltics and defecation was significantly longer in the laparotomic cholecystectomy group compared to the group of laparoscopic cholecystectomy. CONCLUSIONS: Statistically significant impairments including hypoxia, hypocapnia and hyperventilation were observed in the patients submitted to laparotomic cholecystectomy, indicating the presence of objective respiratory risk, especially in elderly patients and patients with obstructive pulmonary diseases or cardiac insufficiency.

[Video thoracoscopic therapy of recurrent spontaneous pneumothorax]. / Videotorakoskopsko lijecenje recidivnoga spontanog pneumotoraksa.

We report our first experience in surgical treatment of recurrent spontaneous pneumothorax using video-assisted thoracic surgery (VATS). From May 1995 to April 1998, 38 cases of recurrent spontaneous pneumothorax were treated using the VATS approach. All patients were previously treated by other methods (conservative, thoracocentesis, chest-tube drainage). We successfully managed VATS procedure in all our patients (wedge resection 28, bullectomy 1, partial pleurectomy 2, pleural abrasions 36). Complications include persistent air leak (4), prolonged bleeding (1) and supraventricular tachycardia (1). The mean duration of chest drainage was 3.9 days (range 3 to 15 days). All patients received antimicrobial chemoprophylaxis with single-dose of 2 g Ceftriaxone intravenously prior to surgery and average postoperative patient-controlled analgesia with 0.15 mg of buprenorphin. Utilisation resource analysis showed great advantage in favour of VATS procedure compared to retrospectively analysed thoracotomied patients. We conclude that VATS is very useful alternative to conventional thoracotomy in managing cases of recurrent spontaneous pneumothorax.

A case of syphilitic interstitial pulmonary fibrosis.

Diagnosis of late pulmonary syphilis was made in a 72-year old woman on the basis of her medical history of untreated genital syphilis, serological and radiological findings, and the response to therapy. The diagnosis was confirmed two years later by autopsy findings. There was a good correlation between chest x-ray radiography, computed tomography scans, and autopsy findings. In the diagnosis of sarcoidosis and other diseases with similar radiological interstitial lung pattern, syphilitic interstitial pulmonary fibrosis should be carefully excluded.

Recovery of respiratory functional defects after war injuries to the chest.

AIM: Assessment of lung function before, during, and after surgical treatment of war injuries to the chest, and comparison of conservative and operative surgical approach. PATIENTS AND METHODS: A retrospective study of 439 patients with war injuries to the chest inflicted during the wars in Croatia and Bosnia and Herzegovina was performed. Patients were classified by injury mechanism and by physiologic scoring on admission, according to the cardiovascular-respiratory elements of the Injury Severity Score (ISS). "Conservative" surgical treatment with chest tube drainage, appropriate fluid therapy, and antimicrobial and atelectasis prophylaxis was performed in 358 (81.5%) and operations in 81 (18. 5%) patients. Blood gases were analyzed before, during, and after surgical treatments. Pulmonary function was assessed after the stabilization of patients' clinical condition and 3-6 months after the injury. RESULTS: On admission, blood gas profiles showed slight to moderate hypoxemia with consecutive hypercapnia related to the severity of injuries. Surgical treatment left a minimum degree restrictive disorder of ventilation without an obstructive pattern. Definitive repair of lung function presented with normalization of blood gas data, and significantly improved restrictive pattern (p<0.05). There was no difference in definitive lung function between conservatively and operatively treated patients. Mortality was 2%. CONCLUSION: The success of surgical resuscitation was related to ISS scoring. Recovery of respiratory function defects after the injury was not significantly related to the mechanism of injury or the patient's condition at arrival. The recovery of lung function was similar in conservatively and operatively treated patients.

Spirometric disorders in women with genital descensus.

BACKGROUND: We hypothesized that abnormalities in connective tissue, found in women with genital descensus, could impact their pulmonary function. METHOD: Therefore we compared lung flows and volumes between women with (n = 100) and without (n = 100) descensus. RESULTS: Patients exhibited highly significant decrements in all expiratory flows, especially in the peak expiratory flow (-35%) and other flows at large lung volumes. The forced vital capacity and forced expired volume at 1 second, but not their ratio, were also decreased (-16% and -17%, respectively). These differences were exaggerated in postmenopausal subjects and in patients with third degree of descensus, but did not depend on the presence of stress incontinence. Lung flows and volumes did not change between follicular and luteal phase of the cycle, either in patients or in controls. The forced vital capacity decreased with increasing years past the menopauses in patients (65 +/- 10 ml per year), but not in controls. CONCLUSION: In women with genital descensus deteriorations in lung ventilatory function were observed in association with the presence and duration of postmenopauses.

Functional effects of typical lung resections for primary bronchogenic carcinoma.

In 60 patients with primary bronchogenic carcinoma undergoing surgery, pulmonary function studies were performed before, and then 10 days and 3 to 6 months after typical lung resection. Preoperative profiles showed a slight restrictive pattern without air trapping and slightly disturbed gas exchange. The restrictive pattern was not related to clinical, X-ray and endoscopy findings. The alveoloarterial oxygen gradient was smaller in the patients requiring lobectomy than in pneumonectomy patients. After surgery, the volume loss was related to the amount resected, being greater after right pneumonectomy than after left pneumonectomy, smaller after bilobectomy and the least after lobectomy. The obstructive pattern remained unchanged. Diffusion of carbon monoxide decreased significantly less than the volumes after pneumonectomy, but proportionally after lobectomy and bilobectomy. Those with increased alveoloarterial oxygen gradient or increased physiologic dead space showed a significant improvement of their gas exchange after surgery.

[Pulmonary function after decortication of the lung]. / Plucna funkcija nakon dekortikacije pluca.

From 1985 to 1994 decortication of the lung was performed in 60 patients. The indications were: specific and non-specific empyema, chronic pleural effusion, chronic pneumothorax and hemothorax. To assess the lung function, the measurements of vital capacity, forced expiratory volume and maximum breathing capacity, as well as blood gas analysis were performed preoperatively and six months after the operation. The slight improvement of lung function was seen postoperatively. Usual postoperative complications were successfully treated. Indications for decortication for the purpose of improving the lung function remain questionable.

An increase in micropulmonary red cell mass in hyperlipidaemic patients.

It is known that pulmonary microcirculation rheology is partly affected by plasma levels of lipoproteins, but only a few data are available for humans. Therefore, in a sample of 30 normal volunteers and 90 patients with various types of primary hyperlipoproteinaemia, the plasma levels of total cholesterol (Chol), low density cholesterol (LDL), the high density cholesterol (HDL), triglyceride (Tg) and fibrinogen (Fib) were measured in conjunction with determinations of plasma viscosity (PV) and the pulmonary capillary red cell volume (RCVc). RCVc was estimated from measurements of the vascular component of the single-breath-diffusing lung capacity for carbon monoxide, using our own modification of the Roughton-Forster's method. By stepwise regression analysis, the variation in RCVc was almost completely accounted for (r2 = 0.87) by variations in PV, Chol, Tg and the anthropometric confounding factors. The proposed explanations for increased pulmonary capillary red cell mass (up to 151% of the predicted value) in hyperlipidaemic patients included the hypothesis of increased pulmonary microhaematocrit, which agrees with the observed in-vitro lipoprotein-dependent increase in erythrocyte aggregability.

Increase of lung transfer factor in early sarcoidosis.

Dynamic spirometry and the lung transfer factor for CO (TLCO) were determined in 41 non-smoking patients with sarcoidosis before and after steroid treatment. Dynamic spirometry revealed usual stage-dependent restrictive and/or obstructive abnormalities; only maximal expiratory flow rate at 75% FVC (MEF75) was significantly increased after steroid treatment in stage 2 patients. The new finding is that TLCO was increased in stage 1 [on average 21% above the predicted values (p.v.)], but it was decreased in stage 2 (11% below p.v.) and stage 3 (27% below p.v.). The increase in TLCO in stage 1 was predominantly caused by an increase in TLCO membrane component (Dm) (33% above p.v.), while the pulmonary capillary blood volume (Vc') increased less (19% above p.v.). Steroid treatment significantly reduced TLCO, Dm and Vc' in stage 1 (for 14, 17 and 18% of the respective baseline values), whereas it caused TLCO and Dm increases in stage 2 (for 8 and 10% of the respective baseline values). In conclusion, a TLCO in pulmonary sarcoidosis may not only be decreased in its advanced stages, but also exhibit increased values, which appeared related to the subclinical inflammatory reaction in the stage 1 patients.

Increase of pulmonary diffusing capacity in systemic sclerosis.

Pulmonary function tests and chest radiographs of 29 non-smoking systemic sclerosis (SSc) patients were analysed, featuring an apparently paradoxic finding of an increased diffusing lung capacity for carbon monoxide (DLCO). Twenty-one patients (72%) had abnormal pulmonary function, 11 of them had restrictive disease (38%), six (21%) had isolated DLCO increase, four (14%) had isolated DLCO reduction, while two patients had obstructive disease (7%). Chest X-ray revealed interstitial abnormalities consistent with pulmonary fibrosis in all four patients with isolated DLCO reduction, in one obstructive patient and in six restrictive patients. In patients with DLCO increased steroid treatment significantly reduced DLCO (P < 0.05) and membrane DLCO component (Dm) (P < 0.05). Hitherto unobserved finding of DLCO increase in SSc patients was associated with shorter duration of SSc (P < 0.05), normal lung mechanics and roentgenogram (P < 0.05) and absence of pulmonary symptoms (P < 0.05). The findings that in some SSc patients DLCO increases suggest that DLCO might prove to be an early and sensitive indicator of acute pulmonary involvement.

[The effect of hemoglobin levels in the blood in pulmonary diffusing capacity]. / Utjecaj koncentracije hemoglobina u krvi na difuzijski kapacitet pluca.

Using a "single breath" method, diffusing lung capacity (DLCO) and unit DLCO (KCO) were measured in 19 patients with chronic sideropenic anemia and 19 healthy women who were without any clinical or radiologic evidence suggestive of cardiorespiratory disease. Anemic patients, compared to the control group, had significantly reduced DLCO (% predicted) and KCO (% predicted) (p < 0.01). Each 10 g/L hemoglobin (Hb) reduction below a normal value of 136 g/L corresponded to 2% DLCO% and 3% KCO% reductions. For all examinees, where the range of Hb was from 50 to 150 g/L, a significant positive low linear correlation was noted between DLCO% and HB (r = 0.31; p = 0.049) and KCO% and Hb (r = 0.43; p = 0.005). Analyzing only anemic patients, where the range of Hb was from 50 to 109 g/L, no significant correlation was found between Hb and DLCO% or KCO%. Therefore, in patients with chronic sideropenic anemia DLCO is lowered less then expected, so one should not adjust measured DLCO or KCO values to standard Hb concentration, because probably various pathophysiological compensatory mechanisms affect DLCO components in unknown manner, changing the relationship between Hb and DLCO.

Model for radionuclide evaluation of left-to-right ductal shunts.

A model for radionuclide evaluation of left-to-right ductal shunts was designed. It was a generalization of the standard Maltz-Treves method, accounting for the possibility that distribution of the shunt flow between the two lungs differs from that in the right ventricular (RV) output (Fs). This yields a new formulation in which the ratio of ductal flow to pulmonary flow (Fd/Fp) equals a weighted average of Fd/Fp obtained separately for the right lung (RL) and the left lung (LL), i.e. Fd/Fp = R(Fd/FpP)RL+ (1-R) (Fd/Fp)LL; where R is the fraction of the RV output going to the right lung. Separate shunt-flow ratios can be obtained by conventional analysis of the respective lung radiohistogram, while R can be determined from the upslopes of these curves. Formulas were derived rigorously from basic principles, so that the ultimate clinical validity of the method depends on radioangiographic assessment of R, (Fd/Fp)RL and (Fd/Fp)LL. Due to asymmetry of flows there is no true referent method for patients with ductal shunts. Therefore a simulation study, using quasi-real data, was utilized, yielding satisfactory performances of the algorithm: (Fp/Fs) calculated = 0.92 (Fp/Fs)stimulated +0.15 (r = 0.878).

Association between asbestos-related pleural plaques and resting hyperventilation.

This study reports an association between pleural plaques and resting hyperventilation in a group of workers exposed to asbestos. Information on exposure level, pack-years of cigarette smoking, chest radiographs, ventilation parameters, single-breath diffusing lung capacity, and arterial gases were obtained for 344 workers. After the exclusion of 37 workers for isolated parenchymal fibrosis, combined pleuroparenchymal fibrosis, or diffuse pleural thickening, 55 subjects with isolated pleural plaques were evaluated against 252 no-plaque workers. A quantitative pleural score revealed mild pleural disease. Forty-four workers with plaques (80%) had hypocapnia induced by resting hyperventilation. The quantitative pleural score correlated significantly with the partial pressure of carbon dioxide in arterial blood (correlation coefficient = 0.7). A decrement in forced vital capacity was associated with plaques, whether controlled for age, smoking, and exposure or not. It was concluded that the resting hyperventilation observed in some asbestos-exposed subjects is related to the presence of mild pleural plaques and a restrictive disorder.

About mechanisms of prostaglandin E1 induced deterioration of pulmonary gas exchange in COPD patients.

Prostaglandin E1 (PGE1) has been reported to attenuate COPD-related pulmonary hypertension and to slightly lower the arterial oxygen tension (PaO2). In order to infer the involved mechanisms, the effects of intravenous infusion of PGE1 on pulmonary haemodynamics, diffusing lung capacity for CO (DLCO), membrane diffusing capacity (Dm), pulmonary capillary blood volume (Vc), physiological shunt (Qps/Qt), arterial blood gases and other lung functional indices were evaluated in 20 COPD patients with pulmonary hypertension and, excluding right catheterization, in 14 control subjects. The examines were studied at baseline and during infusion of 20-30 ng kg-1 min PGE1 or placebo. In control subjects PGE1 only caused systemic arterial pressure decrease (-17.8%). In COPD patients, as expected, PGE1 increased cardiac index (16.2%), but decreased systemic arterial pressure (-21.2%), pulmonary arterial pressure (-27.9%), pulmonary vascular resistance (-45.4%) and PaO2 (-10.4%), worsening their hypoxaemia. However, the effect of PGE1 on DLCO was an increase (11.9%), due to an increase in Vc (15.2%) and less markedly in Dm (4.9%). Physiological and anatomical shunts were increased with PGE1 (20.2% and 14.8%) and the overall ventilation/perfusion ratio decreased from 0.89 to 0.79. Decrements in PaO2 correlated with increments in Qps/Qt (r = 0.86). In conclusion, in COPD patients studied, PGE1 increased DLCO, which compensated for the deleterious effect of increased cardiac output on alveolar-capillary gas equilibration. Therefore, worsening of hypoxaemia during PGE1 infusion was related with increased right-to-left shunt and deterioration of ventilation-perfusion relationship.

High resolution pulmonary computed tomography scans quantified by analysis of density distribution: application to asbestosis.

A new method for quantitative evaluation for high resolution computed tomography (HRCT) of the lungs was developed by assessment of the distribution of radiological densities within the lung slices. To enable effective reduction of data and improve the sensitivity of detection of abnormalities, the density distributions were analysed by curve fitting through the gamma variate model. The output of two variables proved most representative: the most frequent density (Hoansfield units; HU) and width of distribution (HU). The method was applied to seven patients with early asbestosis (positive histological finding and International Labour Office (ILO) profusion score up to 0/1), 15 patients with advanced stage of asbestosis (positive histological finding and ILO score above 1/2), and 13 normal controls. All patients with early asbestosis had isolated reduction of diffusing lung capacity to carbon monoxide (DLCO), whereas all patients with advanced asbestosis had reduced DLCO and restrictive disease; two of them also had an obstruction pattern. The most frequent densities were significantly greater in the advanced asbestosis group (-567 HU) when compared with both the early asbestosis group (-719 HU; p = 2 x 10(-6)), and controls (-799 HU; p = 0), and they also discriminated significantly between the early asbestosis group and controls (p = 0.0002). Significantly stronger linear correlations were established between DLCO and the most frequent densities (r = 0.86) than between DLCO and HRCT score (r = 0.57) or ILO score (r = 0.34). It is concluded that fitting the curve of the density distribution enables a more objective assessment of HRCT pulmonary scans, especially in the early stage of asbestosis.

Effect of a single air dive on pulmonary diffusing capacity in professional divers.

The aim of this study was to determine whether venous gas embolism after a single air dive, evaluated using precordial Doppler monitoring, was associated with alterations in spirometry, lung volumes, arterial blood gases, or pulmonary diffusing capacity for carbon monoxide (DLCO). Postdive time course monitoring of pulmonary function was undertaken in 10 professional divers exposed to absolute air pressure of 5.5 bar for 25 min in a dry walk-in chamber. The US Navy decompression table was followed. Venous bubbles were detected by precordial Doppler monitoring. Two types of decompression were used: air and 100% O2 applied for 21 min during decompression stops. Spirometry, flow-volume, and body plethysmography parameters were unchanged after the dive with air decompression (AD) as well as with O2 decompression (OD). A significant reduction in arterial PO2, on average 20 Torr, was found after the dive with AD. DLCO was decreased in all divers 20, 40, 60, and 80 min after diving with AD (P < 0.001), whereas it was not significantly decreased after diving with OD. Maximal DLCO decrease of approximately 15% occurred 20 min postdive. In AD diving, maximum bubble grade for each individual vs. maximum DLCO reduction correlated significantly (r = 0.85, P = 0.002), as well as DLCO vs. arterial PO2 (r = 0.64, P = 0.017). In conclusion, a reduction in pulmonary diffusing capacity is observed in parallel with the appearance of venous bubbles detected by precordial Doppler. We suggest that bubbles cause pulmonary microembolization, triggering a complex sequence of events that remains to be resolved. Measuring DLCO complements Doppler bubble detection in postdiving assessment of pulmonary function.

Lung diffusing capacity in a hyperbaric environment: assessment by a rebreathing technique.

A rebreathing method was developed for measuring diffusing lung capacity for carbon monoxide (DLCO) in a hyperbaric environment. Twenty two professional naval divers with normal lung function were included in the study. Significant correlations were found between rebreathing and single breath measurements for DLCO (r = 0.94; p less than 0.001; standard error of the estimate (SEE) = 0.66), alveolar volume (VA) (r = 0.79; p less than 0.005; SEE = 0.51), and DLCO/VA (r = 0.83; p less than 0.001; SEE = 0.11). In 17 divers, rebreathing DLCO (DLCOrb) was also measured at 20 minutes pre-dive, during the first decompression stop of the dive to 45 m for 25 minutes, and at 10 minutes post-dive. Compressed air diving was performed in a dry walk-in chamber and the United States Navy decompression table was followed. The pressure induced decrease in the rate of CO binding to haemoglobin was adjusted to normobaric conditions using a theoretical approach. Also, the presence of venous bubbles post-dive was detected by precordial doppler monitoring. A biphasic change in DLCO was noted: initially, DLCO was increased during the dive (p less than 0.005); this was followed by a post-dive decrease; DLCO/VA changed in a similar manner, as VA was only slightly altered. Only a small post-dive precordial doppler bubble grade was found. In conclusion, rebreathing DLCO measurement is a useful respiratory function test in the hyperbaric environment. It appears that an increase in D(L)CO during the compressed air dive is related predominantly to increased pulmonary capillary blood volume caused by increased negativity of the pleural pressure, hyperoxic pulmonary vasodilatation, and cardiorespiratory centralisation of the blood. The decrease in D(L)CO post-dive was only partially related to the presence of the venous bubbles detectable by doppler.

Biphasic lung diffusing capacity: detection of early asbestos induced changes in lung function.

Asbestos related changes in the single breath carbon monoxide diffusing capacity (DLCO) were longitudinally analysed in 14 subjects exposed predominantly to chrysotile asbestos in an asbestos cement factory. These subjects were examined annually over the past nine years; their lung function was initially characterised with increased DLCO as the sole functional abnormality and they had normal chest radiographs. The radiological examination included a chest x ray film and, in the past two years, high resolution computed tomography (HRCT). A biphasic DLCO change was found: an initial increase followed by a relative decrease. The increase in DLCO was mainly caused by an increase in the membrane component (Dm). Indomethacin treatment applied after the sixth annual follow up significantly reduced DLCO and Dm. The decrease in DLCO correlated well with the parenchymal abnormalities found on HRCT, whereas the chest x ray film profusion score for small opacities (ILO classification) was unchanged. In conclusion, the data suggested that, as well as the absolute values of pulmonary function tests, the measurement of progression of functional parameters is essential in the assessment of pleural and parenchymal disease of the lung related to exposure to asbestos. High resolution computed tomography is suggested as the radiological method of choice in subjects with an isolated decrease in DLCO. Exposure to asbestos can be associated not only with a reduction in DLCO, but also with a temporary increase in DLCO caused by a subclinical inflammatory reaction.