Diagnosis of asthma and chronic obstructive pulmonary disease in general practice

There may be an overlap between the clinical pictures of asthma and chronic obstructive pulmonary disease which hampers a clear distinction between the two diseases. Most symptoms presented by patients do not clearly belong exclusively to either asthma or chronic obstructive pulmonary disease. By the nature of their discipline and training, general practitioners focus mainly on symptoms presented, which do not give a decisive answer in the differential diagnosis between the two diseases. Therefore, general practitioners must rely on objective parameters, such as determining the presence and degree of reversibility of airway obstruction, diurnal peak flow variability, bronchial hyper-responsiveness and allergy. This paper puts forward a pragmatic, primary care definition of asthma and chronic obstructive pulmonary disease.     

Occlusion pressure responses in asthma and chronic obstructive pulmonary disease

During CO2 rebreathing we measured ventilation and the pressure generated during the first 0.1 sec of inspiratory effort against a closed airway (P 0.1) in 12 asthmatics during acute exacerbation, 10 normal subjects, and 10 patients with chronic obstructive pulmonary disease. In normal subjects, the ventilatory responst to CO2 correlated with the P 0.1 response measured as delta In P 0.1. Patients with chronic obstructive pulmonary disease showed depressed responses to CO2 in terms of both ventilation and deltaIn P0.1. However, P 0.1 values in the patients with chronic obstructive pulmonary disease were greater than those of the normal subjects when they were compared at an alveolar PCO2 of 60 mm Hg. Asthmatics' responses to CO2 were similar to those of patients with chronic obstructive pulmonary disease. When measured at an alveolar PCO2 of 60 mm Hg, asthmatics' P 0.1 values were greater than those of both normal subjects and patients with chronic obstructive pulmonary disease. As the asthmatics' airway obstruction decreased so did their P 0.1. The asthmatics, and to a lesser extent the patients with chronic obstructive pulmonary disease, demonstrated increased inspiratory muscle activity that could not be explained on the basis of chemical drive or alterations in functional residual capacity. In the case of the asthmatics it was possible that the increased inspiratory muscle activity was a response to airway obstruction.     

Late pulmonary impairment following allogeneic bone marrow transplantation

The pulmonary function of 88 consecutive leukemic patients who had undergone allogeneic bone marrow transplantation (BMT) was studied beforehand, at 3 months, at 6 months, and annually thereafter until 5 years after grafting. The parameters for function which are indicative for obstructive and restrictive lung disease deteriorated in all patient groups during the first 3 to 6 months after BMT but partially recovered within one year. Long-term decline in lung function was similar in all patient groups, and neither the onset nor the magnitude of pulmonary dysfunction was related to the occurrence of pulmonary impairment within 6 months after grafting. Multivariate analysis was then employed to assess predictors for long-term pulmonary disease. Despite the obvious effect of chronic graft versus host disease on the course of lung function, it was in itself not a significant predictor of long-term pulmonary outcome. Rather, the conditioning regimen turned out to be indicative; compared with busulfan, fractionated total body irradiation was demonstrated to be clearly superior with a lower incidence of both restrictive and obstructive long-term lung impairment. Our data indicate a previously unknown long-term side effect of busulfan conditioning.     

Cellular mechanisms of adrenaline-stimulated anion secretion by the mouse endometrial epithelium

As freon is limited in its use as a generator for aerosol inhalation, powder particles are used as an alternative for inhalation therapy. The pulmonary deposition and clearance of inhaled powder particles was studied by positron emission tomography (PET) in ten patients with chronic obstructive pulmonary disease (COPD) and in five normal controls. The powder, 5 microm in mean diameter, was water soluble and labelled with 2-deoxy-2-[18F]-fluoro-D-glucose (18FDG). Powder inhalation was done with single deep inspiration from residual volume to total lung capacity. The initial deposition ratio in the right or left lung field to total inhaled dose, measured by an anteroposterior rectilinear scan, did not differ between normals and COPD patients. Ratios of radioactivity detected within the central and peripheral regions (the central to peripheral ratio) measured by the PET scan was not significantly different between COPD patients (4.8+/-2.6, mean+/-SD) and normals (2.6+/-0.8, mean+/-SD). However, the regional powder deposition in peripheral lung fields measured by the PET scan was significantly more uneven in COPD patients than in normal patients. The clearance rate of 18FDG, defined as the retention ratio of 18FDG activity to the initially deposited 18FDG at 60 and 120 min after inhalation, in the trachea, large bronchi or peripheral lung fields measured by tomographic scan showed a wider variation in COPD patients than in normals. To conclude, inhaled powder tended to be deposited more centrally and was distributed more unevenly in the peripheral lung in chronic obstructive pulmonary disease patients than in normals. This could be a limitation of powder inhalation used for therapy in chronic obstructive pulmonary disease patients.     

Diagnosis and treatment of obstructive lung diseases

Obstructive pulmonary disease can be divided into bronchial asthma and chronic obstructive pulmonary disease. Using a questionnaire, we carried out a survey among doctors in Hordaland county in order to discover how they diagnosed and treated obstructive pulmonary disease. The response rate was 60%; 119 general practitioners and 48 hospital doctors. In spite of recommended guidelines, 20% of the doctors did not perform any kind of spirometry when diagnosing obstructive pulmonary disease. Spirometry after inhalation of bronchodilators or corticosteroids was performed by 29% of the doctors when diagnosing chronic obstructive pulmonary disease and by 43% when diagnosing asthma. 88% of the doctors who participated in our survey preferred to treat asthma with inhalation of beta-agonist or inhalation of corticosteroids, or both. This was in accordance with recommended guidelines. There was greater uncertainty amongst the doctors concerning the treating of chronic obstructive pulmonary disease, and the guidelines were followed to a lesser extent.     

Post-transplant obstructive lung disease ("bronchiolitis obliterans"): a clinical comparative study of bone marrow and lung transplant patients

Patients at a single pulmonary centre who developed obstructive lung disease after bone marrow transplantation (BMT) and lung transplantation (LT) were studied, in order to compare the clinical expression of post-transplant obstructive lung disease (PTOLD) (bronchiolitis obliterans) in these two conditions, which have so far been studied separately. Nine out of 179 patients surviving more than 100 days after BMT (5%) and 9 out of 44 patients surviving more than 100 days after LT (20%) developed post-transplant obstructive lung disease. This was defined by an irreversible airflow obstruction, as characterized by a forced expiratory volume in one second divided by forced vital capacity (FEV1/FVC) of less than 70%, and a FEV1 of less than 70% of predicted value. The mean interval between transplantation and the diagnosis of post-transplant obstructive lung disease was 262 days and 217 days for BMT and LT patients, respectively. In all cases, pulmonary symptoms consisted of dyspnoea and progressively productive cough. Bronchial dilatation on high-resolution computed tomography scans was the main imaging feature present in both groups of patients at the onset of post-transplant obstructive lung disease. The mean FEV1/FVC ratio was 51 and 54% for BMT and LT patients, respectively. All BMT and LT patients had normal transfer coefficient. Clinical chronic graft-versus-host disease was present in all BMT patients before or concurrent with the onset of post-transplant obstructive lung disease, and all LT patients had presented at least one episode of acute lung rejection.(ABSTRACT TRUNCATED AT 250 WORDS)     

Pulmonary thromboembolism

Pulmonary embolism (PE) is a serious complication of chronic obstructive pulmonary disease (COPD). Retrospective studies on patients with COPD treated in the intensive care unit (ICU) were performed to determine: 1) the frequency of PE; 2) the clinical course of PE in cases of COPD in the ICU; and 3) the frequency of PE as a cause of death in the studied group. The frequency of PE was 10.9% in COPD patients. In the group analysed, clinical presentation of PE was characterized by acute severe, life-threatening complications leading to death in 86.7% of cases. PE was the most frequent cause of death (40.6%) in COPD patients in the ICU. The results of treatment of pulmonary embolism in chronic obstructive pulmonary disease are poor and mortality in this group of patients is very high. We believe that improvement of management can be achieved by antithromboembolic prophylaxis, which should be instituted as soon as possible in all patients with chronic obstructive pulmonary disease in the intensive care unit.     

Two-dimensional echocardiographic assessment of right cardiac pressure overload in patients with chronic obstructive airway disease

Two-dimensional echocardiography was used to estimate right cardiac pressure overload in patients with chronic obstructive airway disease. Area measurements of the four heart chambers were carried out from the apical four-chamber view. Additionally, the respiratory behaviour of the inferior vena cava was examined from the subcostal view. A good apical imaging of the four-chamber view for area measurement was obtained in 44 out of 48 patients with chronic obstructive airway disease. The respiratory behaviour of the inferior vena cava was investigated from the subcostal view in 38 patients. Within 8 days after echocardiography, right cardiac catheterization was carried out in order to measure pulmonary artery and right atrial mean pressures and to determine pulmonary vascular resistance. A good correlation was found between pulmonary artery mean pressure and the following echocardiographic parameters: area index (area/body surface) of the two right heart cavities (r = 0.83), right-to-left ventricular area ratio (r = 0.82) and right-to-left cardiac area ratio (ratio between the added areas of both right heart cavities on the one side and the added areas of both left heart cavities on the other; r = 0.82). Correlation between these parameters and pulmonary vascular resistance (r = 0.71, 0.66 and 0.71, respectively) and between the right atrial mean pressure and the right atrial area index was less close (r = 0.64). On the other hand, the respiratory behaviour of the inferior vena cava proved to be highly specific but not very sensitive in predicting a pathological right atrial pressure.(ABSTRACT TRUNCATED AT 250 WORDS)     

The effect of alpha-tocopherol and beta-carotene supplementation on COPD symptoms

The effects of alpha-tocopherol (50 mg/d) and beta-carotene (20 mg/d) supplementation on symptoms of chronic obstructive pulmonary disease were studied among the 29,133 participants of the Alpha-Tocopherol Beta-Carotene Cancer Prevention Study undertaken to investigate the effects of these two substances in the prevention of lung and other cancers. During the follow-up the supplementations did not affect the recurrence or incidence of chronic cough, phlegm, or dyspnea. The prevalence of chronic bronchitis and dyspnea at baseline was lower among those with high dietary intake of beta-carotene (OR = 0.78 and 0.67, respectively) or vitamin E (OR = 0.87 and 0.77) and high serum beta-carotene (OR = 0.59 and 0.62) and alpha-tocopherol (OR = 0.76 and 0.82). High intake and serum levels of retinol were associated with low prevalence of dyspnea (OR = 0.84 and 0.80, respectively) but not with chronic bronchitis. The results indicate no benefit from supplementation with alpha-tocopherol or beta-carotene on the symptoms of chronic obstructive pulmonary disorders but support the beneficial effect of dietary intake of fruits and vegetables rich in these compounds.     

Chronic obstructive pulmonary disease stage and health-related quality of life. The Quality of Life of Chronic Obstructive Pulmonary Disease Study Group

BACKGROUND: The American Thoracic Society recently recommended that chronic obstructive pulmonary disease be staged on the basis of the percentage of predicted FEV1. OBJECTIVE: To examine 1) the relation between the american Thoracic Society system for staging chronic obstructive pulmonary disease and health-related quality of life and 2) the effect of self-reported comorbid conditions on health-related quality of life. DESIGN: Cross-sectional study. SETTING: Outpatient clinics of respiratory departments of four hospitals and one primary health care center in spain. PATIENTS: 321 consecutive male patients with chronic obstructive pulmonary disease. MEASUREMENTS: Functional respiratory impairment, FEV1, respiratory symptoms, and health-related quality of life. Respiratory symptoms and health-related quality of life were measured by using the Spanish version of the St. George's Respiratory Questionnaire and the Nottingham Health Profile. RESULTS: Patient scores on the St. George's Respiratory Questionnaire were moderately to strongly associated with disease staging (r = 0.27 to 0.51). Compared with reference values, values for health-related quality of life for patients with stage I disease were substantially higher on the St. George's Respiratory Questionnaire (6 and 34; p < 0.001) and values for impairment were significantly greater in stage 1 patients with comorbid conditions (19 and 36; P = 0.001). At least one concomitant chronic condition was found in 84% of study patients. Comorbid conditions only partly influenced the observed pattern of deterioration of health-related quality of life with worsening stages of disease. CONCLUSION: Staging criteria for chronic obstructive pulmonary disease based on percentage of predicted FEV1 separated groups of patients with varying degrees of impairment in health-related quality of life. Contrary to expectations, even patients with mild disease showed substantially compromised health-related quality of life. Comorbid conditions influenced the relation between chronic obstructive pulmonary disease and health-related quality of life.     

Left ventricular function during respiratory failure

Indirect measures of left ventricular function were studied in seven patients with respiratory failure secondary to chronic obstructive pulmonary disease to determine if there were a relationship between left ventricular function and treatment of the pulmonary disease. All patients were studied during acute episodes while in respiratory failure having arterial Pco2 (Paco2) values greater than 49 torr with no clinical evidence of left ventricular failure. Indirect methods to evaluate left ventricular function included the use of the Swan-Ganz catheter for pulmonary capillary wedge pressure measurement, systolic time intervals, and cardiac output. There was improvement in left ventricular function with treatment of the respiratory failure manifested by decreases in the wedge pressure and pre-ejection period/left ventricular ejection time ratio, and an increase in the dp/dt/pulmonary capillary wedge pressure with treatment of the chronic obstructive pulmonary disease. The improvement in left ventricular function suggests that there is a depression of left ventricular function in respiratory failure. The depressed function improved with therapy of the lung disease without additional medication directed at cardiac function.     

Hypercapnic respiratory acidosis precipitated by hypercaloric carbohydrate infusion in resolving septic acute respiratory distress syndrome: a case report

Complications may occur when nutritional support is administered either parenterally or enterally. Inappropriate nutritional formulas with high carbohydrate loads can precipitate respiratory failure in patients with compromised lung function, induce respiratory distress which manifests as dyspnea and tachypnea in an originally normal lung condition, produce hypercapnic acidosis in mechanically ventilated patients with chronic obstructive pulmonary disease (COPD) as well as patients recovering from acute respiratory distress syndrome (ARDS) without chronic lung disease, or result in difficult weaning. Hypercaloric mixed substrates administered either parenterally or enterally can also have profound impacts on gas exchange and energy expenditure. This report describes a patient who experienced exacerbation of respiratory distress and hypercapnic acidosis during recovery from septic ARDS as the result of a nutritionally-related increase in CO2 production. As carbohydrate calories were decreased, CO2 production diminished and the hypercapnia was resolved. The importance of indirect calorimetry cannot be overemphasized during tailoring of nutritional support for the critically ill patients.     

Pathophysiology of the respiratory system related to anesthesia

The pathophysiology of the respiratory system can be viewed by simply evaluating the status of a functional residual capacity (FRC). More specifically, patients with airways that are characterized as extremely compliant or "floppy" will have an increased FRC, which is the hallmark of chronic obstructive pulmonary disease. Patients with noncompliant, "stiff" lungs suffer from a form of restrictive disease with a resultant reduction in the FRC. Hence, the implications for anesthesia care focus on the FRC; that is, raising the FRC in the restrictive disease patient and normalizing or preventing further increase in the FRC in the patient with chronic obstructive pulmonary disease.     

Liver transplantation for primary and metastatic liver cancers

Halotherapy was used for sanatorium rehabilitation in 29 patients with chronic obstructive pulmonary diseases (chronic bronchitis and asthma). Significant positive effects of this method resulted in the improvement of the flow-volume parameters curve of lung function and in hypotensive effects on blood pressure. Halotherapy is recommended for use in patients suffering from chronic obstructive pulmonary diseases with hypertension or coronary heart disease.     

Multidisciplinary treatment of chronic pulmonary insufficiency. 4. The influence of intrathoracic pressure variations on increases in pulmonary vascular pressure during exercise in patients with chronic obstructive pulmonary disease

In the present era of direct monitoring of pressure in patients with chronic obstructive pulmonary disease (COPD), an appreciation of all factors that may influence the observed pulmonary vascular pressures is essential. Our study examines the impact of respiratory variations in intrathoracic pressure on the recorded pulmonary vascular pressures in 28 patients with COPD. Althouth pulmonary hypertension was present in only nine subjects at rest, all had an abnormal increase in the mean pulmonary arterial pressure during supine exercise. In 15 subjects, this abnormal response was, in part, related to an increase in pulmonary arterial wedge pressure to 15 mm Hg or more. The increase in pulmonary arterial wedge pressure was directly related to the amplitude of the peak-to-peak respiratory variation of such wedge pressure. This variation correlated with the specific airway resistance but was not related to the arterial oxygen pressure or pulmonary vascular resistance. These findings indicate the important influence of exaggerated respiratory effort on the measurement of pulmonary arterial wedge pressure and mean pulmonary arterial pressure in patients with chronic obstructive pulmonary disease.     

A mentor-based laboratory management elective for residents

BACKGROUND: A combination metered-dose inhaler aerosol containing ipratropium bromide and albuterol sulfate has been reported to be more effective than either of its components in patients with chronic obstructive pulmonary disease. The dose of albuterol sulfate is equal in moles per liter to the dose of albuterol base used in the commercially available metered-dose inhalers. OBJECTIVE: To compare the safety and efficacy of the combination of ipratropium bromide and albuterol sulfate with a commonly prescribed albuterol metered-dose inhaler containing albuterol base alone. METHODS: Investigators at different sites performed a double-blind, 29-day trial involving 357 patients with chronic obstructive pulmonary disease. Efficacy measurements were taken at 15, 30, and 60 minutes after treatment with study medication and then hourly up to 6 hours on days 1 and 29 of the trial. The primary end point was improvement in forced expiratory volume in 1 second. Clinical status was followed up and safety monitoring was also performed. RESULTS: The combination produced a significantly greater peak and mean improvement in forced expiratory volume in 1 second over albuterol base alone on both test days. Similar changes were seen with forced vital capacity. Evaluations of clinical status were better for patients receiving combination therapy, and some improvements were statistically significant. The overall incidence of adverse effects was similar in the 2 treatment groups. CONCLUSION: We conclude that a combination of ipratropium bromide and albuterol sulfate is more effective at improving pulmonary function than albuterol base alone, with no potentiation of adverse effects.     

Psychological factors associated with use of home nebulized therapy for COPD

This study examined the relationship between adherence to domiciliary nebulized therapy and psychological factors; patient attitudes, anxiety, depression, and quality of life. Ninety three patients aged 45-77 yrs with chronic obstructive pulmonary disease (COPD) and using domiciliary nebulizers were recruited from a hospital database. They completed the St George's respiratory questionnaire (SGRQ)-1 and the hospital anxiety and depression scale (HADS) and attended a semistructured interview. Their usual nebulizers were replaced by Dataloggers, which record the date, time and duration of each treatment, to use for 4 weeks. The SGRQ was then repeated (SGRQ-2). Eighty two patients completed the study. Fifty six percent were poorly adherent; taking less than 70% of the dose prescribed (or less than 60% on regimens of > or = 5 times daily). The total scores on the SGRQ-2 were negatively correlated with percentage adherence. Multiple regression analysis showed that the SGRQ-2 total score was associated with percentage adherence, depression score, feeling supported by clinic staff, and patients feeling that they tried to ignore their chest disease. Patients who report poor quality of life are more likely to be depressed, feel unsupported by clinic staff and be poorly adherent to treatment. Increased levels of clinic support, with the addition of psychological treatments, may be of benefit to some patients with chronic obstructive pulmonary disease.     

Sleep-related O2 desaturation and daytime pulmonary haemodynamics in COPD patients with mild hypoxaemia

It has been hypothesized but not firmly established that sleep-related hypoxaemia could favour the development of pulmonary hypertension in chronic obstructive pulmonary disease (COPD) patients without marked daytime hypoxaemia. We have investigated the relationships between pulmonary function data, sleep-related desaturation and daytime pulmonary haemodynamics in a group of 94 COPD patients not qualifying for conventional O2 therapy (daytime arterial oxygen tension (Pa,O2) in the range 7.4-9.2 kPa (56-69 mmHg)). Nocturnal desaturation was defined by spending > or = 30% of the recording time with a transcutaneous O2 saturation < 90%. An obstructive sleep apnoea syndrome was excluded by polysomnography. Sixty six patients were desaturators (Group 1) and 28 were nondesaturators (Group 2). There was no significant difference between Groups 1 and 2 with regard to pulmonary volumes and Pa,O2 (8.4+/-0.6 vs 8.4+/-0.4 kPa (63+/-4 vs 63+/-3 mmHg)) but arterial carbon dioxide tension (Pa,CO2) was higher in Group 1 (6.0+/-0.7 vs 53+/-0.5 kPa (45+/-5 vs 40+/-4 mmHg); p<0.0001). Mean pulmonary artery pressure (Ppa) was very similar in the two groups (2.6+/-0.7 vs 2.5+/-0.6 kPa (19+/-5 vs 19+/-4 mmHg)). No individual variable or combination of variables could predict the presence of pulmonary hypertension. It is concluded that in these patients with chronic obstructive pulmonary disease with modest daytime hypoxaemia, functional and gasometric variables (with the noticeable exception of arterial carbon dioxide tension) cannot predict the presence of nocturnal desaturation; and that mean pulmonary artery pressure is not correlated with the degree and duration of nocturnal hypoxaemia. These results do not support the hypothesis that sleep-related hypoxaemia favours the development of pulmonary hypertension.     

Antibodies to prothrombin crossreact with plasminogen in patients developing myocardial infarction

This study aimed to determine the differences in haemodynamic responses to a standard incremental exercise test between outpatients with chronic obstructive pulmonary disease (COPD) and age-matched controls and to discover the relationship between severity of airflow obstruction and exercise haemodynamics in COPD. Twenty-two male patients with COPD (forced expiratory volume in one second (FEV1)/vital capacity (VC))<80% predicted) and 20 age-matched male controls performed an incremental exercise test (10 W x min(-1)) with ventilatory function and changes in stroke volume (deltaSV) and cardiac output (deltaCO) measured by means of electrical impedance cardiography (EIC). Submaximal deltaSV and deltaCO were lower in COPD patients. Peak exercise deltaSV were equal in patients and controls (128+/-33 versus 129+/-29%, p=0.98), whereas peak deltaCO was lower in patients (COPD versus controls: 232+/-71 versus 289+/-54%, p<0.005). In COPD patients, FEV1 (% pred) was significantly correlated to deltaSV at all submaximal exercise intensities, to peak exercise deltaSV and to peak exercise deltaCO. FEV1/VC (% pred) was significantly correlated to deltaSV at 30 and 60 W. In conclusion, in chronic obstructive pulmonary disease an aberrant haemodynamic response to exercise was found, especially in patients with severe airflow obstruction. This aberrant response is related to the degree of airflow obstruction and may limit exercise performance in patients with severe chronic obstructive pulmonary disease.