The effects of PAP therapy on energy metabolism in patients with obstructive sleep apnea syndrome.

INTRODUCTION: In this study, changes in energy metabolism before and after treatment were compared in obstructive sleep apnea syndrome (OSAS) patients who received positive airway pressure therapy. MATERIALS AND METHODS: Thirty-nine patients (22 male, 17 female) were admitted to study. Patients for PAP therapy who had moderate to severe in polysomnography were included. Values of energy metabolism were recorded during three days via metaboic holter device, before and after PAP therapy. RESULT: The mean age of the patients was 51.53 ± 11.16 year. In 15 (38.46%) of the patients BPAP, and in 24 (61.54%) of the patients CPAP treatment started. Three days after using metabolic holter device: the total daily energy consumption of the patients was found to be 482,4 ± 296.1 kcal/day before treatment and 524.5 ± 343.1 kcal/day after treatment (p<0.0001); patients' daily physical activity was 7867 ± 3319 steps/day before treatment and 12.416 ± 1451 steps/day after treatment, which was considered statistically significant (p<0001); the total daily resting period of the patients was 7.90 ± 1.36 hours/day before treatment and 7.44 ± 1.42 hours/day after treatment, considered statistically significant (p<0001); the total sleep duration of the patients was 5.50 ± 1.88 hours/day before treatment and 5.87 ± 1.20 hours/ day after treatment, considered statistically significant (p<0001). CONCLUSIONS: In our study, we found that daily physical activity and energy consumption increased with PAP treatment. With PAP treatment, obesity, diabetes and hypertension can be controlled. In our study, since PAP treatment was effective with effective sleep, the immobilization time was decreased and therefore the duration of daytime physical activity was prolonged. With these effects, patients' compliance with treatment increases. In conclusion, PAP treatment should be recommended in patients with moderate and severe OSAS.

Assessment of atrial electromechanical delay and influential factors in patients with obstructive sleep apnea.

PURPOSE: The interaction between moderate-to-severe obstructive sleep apnea (OSA) and cardiac arrhythmias, especially atrial fibrillation (AF), is well known. We aimed to determine whether atrial electromechanical parameters assessed by tissue Doppler imaging (TDI) would be affected in moderate-to-severe OSA, and detect the influential factors of atrial electromechanical parameters in these patients. METHODS AND RESULTS: Interatrial and intra-atrial electromechanical delay was measured by TDI in patients with moderate-to-severe OSA (n = 64) and control subjects (n = 39). P-wave dispersion (PWD) was calculated on the 12-lead ECG. Interatrial and intra-atrial electromechanical delay was significantly higher in the OSA group when compared with the controls (52.26 ± 12.9 vs 29.61 ± 11.26, P < 0.0001 and 18.90 ± 8.13 vs 8.71 ± 5.46, P < 0.0001; respectively). PWD was higher in the OSA group (46.09 ± 13.40 ms vs 34.10 ± 10.75 ms, P < 0.0001). Interatrial electromechanical delay had a positive correlation with PWD (r = 0.490, P < 0.0001), left atrial (LA) diameter (r = 0.383, P = 0.002), LA volume index (r = 0.354, P = 0.004), and apnea-hypopnea index (r = 0.365, P = 0.003). In addition, interatrial electromechanical delay was negatively correlated with the magnitude of the lowest oxygen saturation percentage (r = -0.498, P < 0.0001). CONCLUSION: This study showed that interatrial and intra-atrial electromechanical delay and PWD were prolonged in patients with moderate-to-severe OSA. LA dilatation, hypoxemia, and the severity of the disease may contribute a prolongation in interatrial electromechanical delay via atrial structural and electrical alterations, which may predict the risk of future AF development in patients with moderate-to-severe OSA.

Saddle pulmonary embolism visualized by real time three-dimensional echocardiography.

Saddle pulmonary embolism is defined as a visible thromboembolus straddling the bifurcation of the main pulmonary artery. It is very unusual to visualize a pulmonary artery thrombus on transthoracic echocardiography. We describe a case of a saddle embolus of the main pulmonary artery visualized by real time three-dimensional echocardiography and successfully treated with intravenous unfractionated heparin, followed by oral anticoagulation achieving a complete dissolution of the thrombus.

The prognostic value of serum epidermal growth factor receptor level in patients with non-small cell lung cancer.

Epidermal growth factor receptor (EGFR) has been implicated as a factor indicating tumour progression or as a prognostic factor in non-small cell lung cancer (NSCLC), in which its overexpression is often detected. The usefulness of identifying EGFR in serum from patients with NSCLC is controversial. This study was designed to identify serum EGFR levels in patients with NSCLC and to evaluate the relationship between serum EGFR levels and clinical stage, histological subtype and survival time. Serum EGFR levels were measured using quantitative enzyme-linked immunosorbent assay. The study included 43 patients with NSCLC and 16 healthy controls. The histological classification was 29 squamous carcinomas and 14 adenocarcinomas. Serum samples were collected before treatment.There was no difference between serum EGFR levels in patients with NSCLC (17.53+/-8.09 fmol/mL) in comparison with those healthy controls (16.88+/-7.08 fmol/mL; p=0.912). There was also no difference in serum EGFR levels according to clinical stage or histological subtype. There was no relationship between serum EGFR levels and survival time in patients with NSCLC. The study's results suggest that, the utility of serum EGFR levels in patients with NSCLC as a tumour marker or as a prognostic factor is limited. However, further prospective studies on a large number of patients will be necessary to confirm this study's results.

Effect of CPAP on sleep spindles in patients with OSA.

OBJECTIVE: Consequences of OSAS include excessive daytime sleepiness, divided sleep architecture, impaired neurocognitive performance, and significant psychosocial disruption. In this study we aimed to evaluate sleep spindles changes before and after PAP treatment in patient with OSA. METHODS: Seventy-three consecutive patients (M/F:61/12) who applied to Sleep Disorders Center of Inonu University Hospital and met the inclusion criteria were enrolled to this study. Full-night polysomnography and CPAP titration were performed. RESULTS: Mean AHI were detected as 43,8±24,4 and mean oxygen saturation was 79% in patients under full-night PSG. Singificant increasing were observed on spindle count under CPAP titration (192±98.vs 347±165 per hour p<0.001)) and also significant increasing was recorded on oxygen saturation (79±15 vs 94±4% p<0.001). CONCLUSION: Both spindle count and oxygen saturation were recorded to be significantly increased under CPAP titration while there was a significant decrease in apnea-hypopnea. We have shown that significant increase in number of spindles can be achieved with CPAP treatment, those to be decreased in patient with OSA. Number of spindles may play a role as an indicator of better outcome in OSA patients.

The effects of home oxygen therapy on energy metabolism in patients with COPD.

Background: COPD is preventable and treatable and is characterized by completely nonreversible airflow obstruction. In this study, we aimed to investigate the effect of long-term oxygen therapy on patients with stage 4 COPD who were followed up and treated at the polyclinic or clinic service. We evaluated the effects of oxygen therapy on energy metabolism and physical activity in patients with COPD. Methods: Nineteen patients with COPD (16 male/3 female), treated with oxygen therapy for the first time, were included in this study. Analysis of arterial blood gases and pulmonary function test was performed. Metabolic Holter device (SenseWear® Armband) was placed pre- and post-oxygen therapy on the patients' arm for at least 3 days. This device captures Holter data in a digitized electronic system, and the daily average value was calculated from the data. Results: Post-oxygen treatment showed a significant increase in energy expenditure by patients with COPD (pretreatment, 1,497±596 joule; posttreatment, 2,977±5,985 joule; P=0.044). Moreover, number of steps during walking (pretreatment, 2,056±256; posttreatment, 2,120±195; P=0.03), resting (pretreatment, 6.36±3.31 hours; posttreatment, 3.47±2.19 hours; P<0.03), and sleeping (pretreatment, 4.23±2.13 hours; posttreatment, 2.33±1.42 hours; P<0.00) showed significant differences. Increased daily energy expenditure in patients with respiratory failure was detected with long-term oxygen therapy. In addition, the immobility of patients decreased and duration of physical activity increased in patients with COPD. Conclusion: In this study, positive effects of long-term oxygen therapy have been demonstrated with respect to energy metabolism and physical activity of patients with COPD. Thus, we recommend that medication adherence and long-term oxygen therapy should begin early in patients with COPD.

[Value of plasma BNP levels as a prognostic marker in lung and heart disorders]. / Akciger ve kalp hastaliklarinda plazma BNP düzeyinin prognostik degeri.

In this study we included 155 subjects, 35 patients with left heart failure, 49 chronic obstructive pulmonary disease (COPD)-cor pulmonale, 26 COPD, 20 pulmonary embolism and 25 healthy subjects. Plasma BNP level in patient with left heart failure was significantly higher than COPD-cor pulmonale, COPD and control subject in respect 1167 +/- 746, 434 +/- 55, 32 +/- 36 and 32 +/- 12 pg/mL. Plasma BNP in group of cor pulmonale was higher than COPD and control subject 434 +/- 55 vs. 32 +/- 12 pg/mL. There were no difference between COPD and control subject 32 +/- 36 vs. 32 +/- 12 pg/mL. In pulmonary embolism BNP was higher than controls 357 +/- 391 vs. 32 +/- 12 pg/mL and BNP levels of massive pulmonary embolism was higher non-massive embolism 699 +/- 394 vs 166 +/- 213 pg/mL. In this study BNP levels negative correlated with EF and positive correlated with pulmonary artery pressure. We suggest that increased BNP levels are correlated with ventricular failure and BNP is diagnostic and prognostic marker of heart failure and increased right ventricular pressure contributes to elevated BNP in patients with PE.

A simple laboratory measurement for discrimination of transudative and exudative pleural effusion: pleural viscosity.

BACKGROUND: The initial step in establishing the cause of an effusion is to determine whether the fluid is a transudate or exudate. Plasma viscosity is influenced by the concentration of plasma proteins and lipoproteins with the major contribution resulting from fibrinogen. In this study we aimed to evaluate the role of pleural fluid viscosity in discrimination of transudate and exudates. MATERIALS AND METHODS: We studied prospectively 63 consecutive patients with pleural effusion in whom diagnostic or therapeutic thoracentesis had been performed. The criteria of Light were applied to differentiate transudates from exudates: 33 patients (23 male, 13 female, mean age=68+/-4 years) had exudates and 30 patients (17 male, 13 female, mean age=68+/-5) had transudates (due to congestive heart failure). Measurements of pleural fluid and plasma viscosity were performed using a viscometer. RESULTS: There was no statistically significant difference between patients with transudate and exudates in respect to plasma viscosity. However, pleural viscosities of the patients with exudates were significantly higher than those of patients with transudate (1.37+/-0.16 mPa vs 0.93+/-0.03 mPa s p<0.001, respectively). Pleural viscosity has a high sensitivity, specificity (94%, 93%, respectively), positive and negative predictive value (97%, 97%, respectively) for the discrimination of transudative or exudatetive pleural fluid. CONCLUSION: We have demonstrated for the first time that pleural viscosity of the exudative effusion is higher than that of transudative effusion with high sensitivity, specificity, positive and negative predictive value. Regarding the simplicity of this measurement, it may play a valuable role in the accurate and fast discrimination of pleural fluid.

Comparison of low-dose dobutamine stress echocardiography and echocardiography during glucose-insulin-potassium infusion for detection of myocardial viability after anterior myocardial infarction.

BACKGROUND: Low-dose dobutamine stress echocardiography (LDDSE) is one of the methods most used to assess myocardial viability. Glucose-insulin-potassium (GIK) infusion has been shown to increase contraction of the ischemic zone. The aim of this study was to compare LDDSE and echocardiography during GIK infusion for detection of myocardial viability. METHODS: Thirty-two patients who had first anterior myocardial infarction (MI) without previous MI were included in the study. Echocardiographic evaluation was carried out on the 7th +/- 2 days after MI. During continuous electrocardiographic, blood pressure and echocardiographic monitoring, an intravenous infusion of dobutamine (3 microg/kg body weight/min) was started with an infusion pump, continued for 5 min and then increased to 5 microg/kg/min and 10 microg/kg/min for another 5 min. The GIK protocol consisted of a fixed dose of insulin (100 microU/kg/h intravenously) and a variable glucose/potassium infusion rate. GIK echocardiography was done at baseline and after 60 min of GIK. The detected viable myocardium was defined as one or two scores decreasing in at least two adjacent abnormal segments during LDDSE and GIK echocardiography. RESULTS: Under resting conditions 225 segments (44%) were normokinetic, 21 segments (4%) dyskinetic, 117 segments (23%) akinetic and 149 segments (29%) hypokinetic. Viability was detected in 20% (57 segments) of the asynergic segments at baseline with GIK echocardiography and in 22% (62 segments) of those segments with LDDSE (P < 0.05). Left ventricular wall motion score index at baseline was 1.87 and it decreased significantly indicating improvement in left ventricular systolic function during both LDDSE and GIK echocardiography (P < 0.001, versus 1.75 and 1.76 respectively). The agreement between LDDSE and GIK echocardiography for detection of myocardial viability was 96%. CONCLUSION: We have shown that GIK echocardiography is similar to LDDSE for detection of myocardial viability. With the support of further clinical studies GIK echocardiography could be used to detect myocardial viability after acute MI.

The role of valvular and thoracic aortic calcifications in distinction between ischemic and nonischemic cardiomyopathy.

Determination of underlying etiology in patients with dilated and globally hypokinetic left ventricles may sometimes be difficult even after detailed history and complete clinical evaluation. Cardiac valvular and thoracic aortic calcifications have previously been reported to be used as a window to diffuse atherosclerosis of the vascular system. The authors prospectively examined the predictive value of mitral annular calcification (MAC), aortic valve calcification (AVC), and thoracic aortic calcification (TAC) in diagnosis of coronary artery disease as the underlying cause of diffuse left ventricular dilatation and systolic dysfunction. The study included 98 consecutive patients (male/female = 76/22, mean age = 58.9 +/- 10.7 years, range: 33 to 75 years) over the age of 30 years admitted to their clinics between October 1999 and December 2001 with signs and symptoms of congestive heart failure associated with documented cardiomegaly. Transthoracic echocardiography and coronary angiography were performed in all patients for the evaluation of valvular calcifications and coronary status. Although there was no significant difference between the groups with and without coronary artery stenosis (CAS), with regard to presence of MAC, patients with CAS tended to have MAC more frequently (12/61, 20% vs 4/37, 11%, p > 0.05). AVC and TAC were found to be significantly more frequent in patients with CAS compared to those without CAS (AVC, 35/61, 57% vs 4/37, 11%, p < 0.001 and TAC, 28/61, 46% vs 2/37, 5%, p < 0.001). While all 3 calcifications had sensitivity under 60%, and specificity and positive predictive value over 75% individually, the presence of any of them had a sensitivity of 80%, specificity of 86%, positive predictive value of 91%, and negative predictive value of 73%. Thus the presence of any of these calcifications distinguished patients with coronary artery disease with a sensitivity of 80% and specificity of 86%. The presence of aortic valvular valve and thoracic aortic calcifications seems to be associated with significant coronary arterial stenosis; however, with relatively low negative predictive values these cannot be used in clinical practice for diagnosis of underlying coronary artery disease in patients with dilated left ventricles and impaired systolic functions.

Increased systemic and regional coagulation activity in patients with mitral stenosis and sinus rhythm.

A hypercoagulable state has been reported in patients with mitral stenosis (MS) and sinus rhythm (SR). However it has been suggested that the coagulation activity may be increased only within the left atrium in MS, with normal peripheral blood levels. The aim of the present study was to assess regional left atrial and systemic coagulation activities by measuring PF1+2 in patients with severe mitral stenosis and sinus rhythm, normal blood clotting times, and no left atrial thrombus. The study was conducted in 25 consecutive patients with moderate-to-severe MS and sinus rhythm who underwent percutaneous balloon mitral valvuloplasty. Transesophageal echocardiography was performed before the valvuloplasty procedure in all patients to exclude the presence of left atrial thrombus and left atrial spontaneous echo contrast (LASEC). There were no statistically significant differences between LASEC-positive and LASEC-negative patients with respect to age, gender, fibrinogen levels, prothrombin time, mitral valve area, mean mitral gradient, pulmonary artery pressure (in all p > 0.05). Regional (left atrial) PF1+2 levels of both LASEC-positive and LASEC-negative patients were significantly elevated when compared to control subjects (p < 0.01). Statistically significant elevated systemic level of PF1+2 was observed only in LASEC-positive patients when compared to control subjects (p < 0.01, p > 0.05, respectively). In conclusion patients with severe mitral stenosis and SR have increased regional coagulation activity in both LASEC-negative and LASEC-positive groups. Although this increased regional coagulation activity has been reflected in peripheral blood of LASEC-positive patients, it has not been reflected in peripheral blood of LASEC-negative patients.

Identification of viable myocardium in patients with chronic coronary artery disease and myocardial dysfunction: comparison of low-dose dobutamine stress echocardiography and echocardiography during glucose-insulin-potassium infusion.

Low-dose dobutamine stress echocardiography (LDDSE) is one of the methods most used to assess myocardial viability. Glucose-insulin-potassium (GIK) has been shown to increase contraction of the ischemic zone. The aim of this study was to compare LDDSE and echocardiography during GIK infusion for detection of myocardial viability in patients with chronic coronary artery disease (CAD) and myocardial dysfunction. Twenty-one patients who had chronic CAD and myocardial dysfunction were included in the study. Glucose-insulin-potassium protocol consisted of a fixed dose of insulin (100 microU/kg/hour IV) and a variable glucose/potassium infusion rate. GIK echocardiography was made at baseline and after 60 minutes of GIK infusion. During continuous electrocardiographic, blood pressure, and echocardiographic monitoring, an intravenous infusion of dobutamine (3 microg/kg body weight/min) was started with an infusion pump and continued for 5 minutes and then increased to 5 microg/kg/min and 10 microg/kg/min for another 5 minutes. The detected viable myocardium was defined as 1 or 2 scores decreasing in at least 2 adjacent abnormal segments during LDDSE and GIK echocardiography. Viability was detected in 19% (52 segments) of the asynergic segments at baseline with GIK echocardiography and 16% (44 segments) of those segments with LDDSE (p>0.05). Left ventricular wall motion score index at baseline was 2.24+/-0.35 and it decreased significantly during both LDDSE (p=0.004 vs 2.11+/-0.36) and GIK echocardiography (p=0.001 vs 2.09+/-0.32). The agreement between LDDSE and GIK echocardiography for detection of myocardial viability was 95%. This study shows that GIK echocardiography is similar to LDDSE for detection of myocardial viability. With the support of further clinical studies GIK echocardiography can be used to detect myocardial viability in patients with chronic CAD.

[Evaluation of spirometric and pulmonary haemodynamic parameters in patients with COPD]. / KOAH'li olgularda pulmoner hemodinamik ve spirometrik parametrelerin degerlendirilmesi.

In this study we aimed to asses the association between the spirometric test which is known to be an indicator of severity of the disease and pulmonary artery pressure, in patient chronic obstructive pulmonary disease (COPD). Study population consisted of 51 patients with COPD. Severity of the disease was graded by the criteria of European Respiratory Society; mildly obstructive 5 patients (FEV1 > 70%), moderately obstructive 10 (FEV1= 50-69%), severely obstructive 36 patients (FEV1 < 50%). Measurement of pulmonary artery pressure was performed bt microcatheterisation method. Statistical analysis was performed between two groups; group I consisted of mildly and moderately obstructive patients, and group II severely obstructive patients. Pulmonary artery pressure of the group II patients was significantly higher than that of group I patients (27 +/- 4 mmHg vs 22 +/- 1.6 mmHg, respectively p< 0.001). There were also statistically significant difference between group I and group II in respect to FEV1% (63 +/- 7 vs 28 +/- 9 respectively p< 0.001), FEV1 L (1.84 +/- 0.46 vs 0.89 +/- 0.36 respectively p< 0.001), FEV1/FVC (71 +/- 10 vs 53 +/- 11 respectively p< 0.001), FVC% (73 +/- 8 vs 47 +/- 10 respectively p< 0.001), and MMF% (38 +/- 13 vs 15 +/- 6 respectively p< 0.001). Pulmonary artery pressure and diameter of right descending pulmonary artery on chest X-ray of the patients were negatively correlated with FEV1%, FEV1 L, FVC and MMF (p< 0.001 for all). We have shown pulmonary artery pressure of the patients with COPD was negatively correlated with the spirometric parameters such as FEV1%, FEV1 L, FVC and MMF. So FEV1 < 50% can be used as an indicator of increased pulmonary artery pressure in patients with COPD.

Inspiratory capacity and forced expiratory volume in the first second in exacerbation of chronic obstructive pulmonary disease.

OBJECT: Periodic exacerbations of symptoms are the major cause of morbidity, mortality and health care costs in patients with chronic obstructive pulmonary disease (COPD). Dyspnea is the major factor affecting the comfort of patients in the exacerbation of COPD. In this study, we aimed to compare the value of forced expiratory volume in the first second (FEV(1)) and inspiratory capacity (IC) measured before and after treatment in exacerbations and in the improvement in dyspnea. METHODS: Eighty-seven patients (male/female, 80/7; mean age, 63 +/- 7) with COPD exacerbation were included in this study. All subjects underwent spirometric tests on the first day and at the end of treatment. The subjects were asked to quantify the sensation of dyspnea that was described to them as a nonspecific discomfort associated with the act of breathing. The patients quantified dyspnea by pointing to a score on a large Borg scale from 0 to 10 arbitrary units. In the beginning and at the end of treatment, forced vital capacity (FVC), FEV(1), forced expiratory flow rate between 25% and 75% of FVC (FEF25-75), peak expiratory flow rate (PEF), IC and Borg score (BS) values were compared. RESULTS: After treatment of COPD exacerbations, FEV(1), FEF25-75, PEF and IC significantly increased, and the BS significantly decreased compared to the initial values. The increase in IC was more significantly correlated with the improvement in BS compared with FEV(1). Admission and discharge day BS was negatively correlated with FEV(1), FEF25-75 and IC. CONCLUSION: We have shown a more dramatic improvement in IC compared with FEV(1) in patients treated as a result of acute exacerbation of COPD. These data suggest that IC may be more useful than FEV(1) during acute exacerbation of COPD. Moreover, IC better reflects the severity of dyspnea in these patients.

CPAP compliance in patients with obstructive sleep apnea syndrome.

Obstructive sleep apnea syndrome (OSAS) is characterized by repeated cessations of breathing during sleep. Major symptoms of this disease are excessive daytime sleepiness, snoring, and witnessed apnea. Most of the patients are treated with CPAP. In this study, we aimed to evaluate the factors affecting adherence to the CPAP treatment. Seventy-one patients were enrolled to this study. Patients were divided into three groups according to CPAP usage. Group I consisted of patients who had never used CPAP, group II consisted of patients who had used CPAP occasionally, and group-III patients had used CPAP treatment regularly. Group-III patients had higher apnea-hypopnea index (AHI) than groups I and II (respectively, 56.6 +/- 27.7, 26.3 +/- 7.5, and 32.3 +/- 7.06; p < 0.000 for both). Oxygen desaturation index was significantly higher in group-III patients comparing to groups I and II (44.6 +/- 22.3, 15.9 +/- 8.3, and 25.6 +/- 9.5; p < 0.000 for all). Our findings have shown that only very severe patients use the CPAP device regularly (mean AHI 56.6 +/- 27.7). Compliance to CPAP treatment seemed to be poor in patients with moderate to severe, AHI about 30, OSAS. Considering the well-established benefits of CPAP treatment in patients with true indications, patients should be encouraged to use CPAP regularly, and complications of OSAS should be keynoted.

Prevalence of COPD: first epidemiological study of a large region in Turkey.

BACKGROUND: Although chronic obstructive pulmonary disease (COPD) is one of the leading causes of mortality and morbidity worldwide, epidemiological data on COPD is very limited. This study was designed to obtain some baseline data on COPD in the Malatya region of Turkey. METHODS: Sixty clusters from urban and rural regions were randomly selected. Ten and seven consecutive households were included in the study from each urban and rural cluster, respectively. A validated questionnaire on the epidemiology of COPD was completed for each participant over 18 by a pulmonary physician. Each subject underwent standard spirometric measurement and early bronchodilation testing. RESULTS: A total of 1160 participants completed the study (93%). Some 6.9% of the participants were found to have COPD (F/M=1/4). While the prevalence of COPD was 18.1% in current smokers over 40 years of age, the prevalence was 4.5% among younger smokers. Some 25.5% of the women and 57.2% of the men were current smokers. Biomass exposure, as a sole reason for COPD, was significantly common among female patients living in rural areas (54.5%). In the development of COPD, the relative risk ratio of cigarette smoke was found to be 3.4 and 3.3 times higher than biomass exposure and occupational exposure, respectively. CONCLUSIONS: Smoking rate and COPD prevalence were found to be unexpectedly high in the region, and biomass exposure is still an important cause of COPD, particularly among females living in rural areas. We think that national policies against smoking and biomass exposure should be implemented immediately.

Role of pleural viscosity in the differential diagnosis of exudative pleural effusion.

OBJECTIVE AND BACKGROUND: Determining the aetiology of an effusion involves assessing if it is an exudate or a transudate. However, a reliable test for determining the aetiology of a pleural effusion is lacking. Pleural viscosity has a high sensitivity and specificity and a high positive and negative predictive value for discriminating exudative and transudative pleural effusions. The aim of this study was to use pleural fluid viscosity to discriminate between various aetiologies of exudative effusions, namely malignant, parapneumonic and tuberculous. METHODS: Seventy consecutive patients (24 women, 46 men, mean age = 67 years) with exudative pleural effusion due to pneumoniae in 24 patients, tuberculous pleurisy in 21 and lung cancer in 25 were studied prospectively. Measurements of pleural fluid and plasma viscosity were performed using Brookfield DV-II viscometer. RESULTS: Pleural viscosity and pleural LDH were highest in the tuberculous pleurisy patients and lowest in the lung cancer patients. Pleural viscosity > or = 1.57 was found to be indicative of tuberculous pleurisy with a sensitivity of 100% and specificity of 95%. Pleural viscosity < 1.39 was found to be indicative of lung cancer with a sensitivity of 100% and specificity of 94%. Pleural viscosity was significantly correlated with pleural albumin (r = 0.34, P = 0.004), protein (r = 0.40, P = 0.001), LDH (r = 0.70, P < 0.001) and plasma viscosity (r = 0.44, P < 0.001), having the most significant value with pleural LDH. CONCLUSION: The pleural fluid viscosity of patients with parapneumonic, tuberculous and malignant effusions are significantly different from each other. Among these groups, tuberculous effusions had the highest viscosity, and malignant effusions from lung cancer the lowest.

Beneficial effect of deep breathing on premature ventricular complexes: can it be related to the decrease in QT dispersion?

It has been reported that deep breathing at 6 breaths/min is associated with reduction of premature ventricular complexes. The beneficial effect of deep breathing is supposed to be due to vagal modulation of sinoatrial and atrioventricular node. Beside the modulating effects of deep breathing, we believe that deep breathing, which is also used in yoga training, might have additional effects via decreasing QT dispersion.