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Biomedical subjects

L C Laursen

Publications and source records attributed to L C Laursen.

At least 19 recordsLinked to original sources
PubMed2004

Volume adjustment of lung density by computed tomography scans in patients with emphysema.

PURPOSE: To determine how to adjust lung density measurements for the volume of the lung calculated from computed tomography (CT) scans in patients with emphysema. MATERIAL AND METHODS: Fifty patients with emphysema underwent 3 CT scans at 2-week intervals. The scans were analyzed with a software package that detected the lung in contiguous images and subsequently generated a histogram of the pixel attenuation values. The total lung volume (TLV), lung weight, percentile density (PD), and relative area of emphysema (RA) were calculated from this histogram. RA and PD are commonly applied measures of pulmonary emphysema derived from CT scans. These parameters are markedly influenced by changes in the level of inspiration. The variability of lung density due to within-subject variation in TLV was explored by plotting TLV against PD and RA. RESULTS: The coefficients for volume adjustment for PD were relatively stable over a wide range from the 10th to the 80th percentile, whereas for RA the coefficients showed large variability especially in the lower range, which is the most relevant for quantitation of pulmonary emphysema. CONCLUSION: Volume adjustment is mandatory in repeated CT densitometry and is more robust for PD than for RA. Therefore, PD seems more suitable for monitoring the progression of emphysema.

Absorptiometry, Photon↗
PubMed2004

Short-term reproducibility of computed tomography-based lung density measurements in alpha-1 antitrypsin deficiency and smokers with emphysema.

PURPOSE: To study the short-term reproducibility of lung density measurements by multi-slice computed tomography (CT) using three different radiation doses and three reconstruction algorithms. MATERIAL AND METHODS: Twenty-five patients with smoker's emphysema and 25 patients with alpha1-antitrypsin deficiency underwent 3 scans at 2-week intervals. Low-dose protocol was applied, and images were reconstructed with bone, detail, and soft algorithms. Total lung volume (TLV), 15th percentile density (PD-15), and relative area at -910 Hounsfield units (RA-910) were obtained from the images using Pulmo-CMS software. Reproducibility of PD-15 and RA-910 and the influence of radiation dose, reconstruction algorithm, and type of emphysema were then analysed. RESULTS: The overall coefficient of variation of volume adjusted PD-15 for all combinations of radiation dose and reconstruction algorithm was 3.7%. The overall standard deviation of volume-adjusted RA-910 was 1.7% (corresponding to a coefficient of variation of 6.8%). Radiation dose, reconstruction algorithm, and type of emphysema had no significant influence on the reproducibility of PD-15 and RA-910. However, bone algorithm and very low radiation dose result in overestimation of the extent of emphysema. CONCLUSION: Lung density measurement by CT is a sensitive marker for quantitating both subtypes of emphysema. A CT-protocol with radiation dose down to 16 mAs and soft or detail reconstruction algorithm is recommended.

Absorptiometry, Photon↗
PubMed2003

The role of the novel D2/beta2-agonist, Viozan (sibenadet HCl), in the treatment of symptoms of chronic obstructive pulmonary disease: results of a large-scale clinical investigation.

Viozan (sibenadet HCl, AR-C68397AA) is a novel dual D2 dopamine receptor, beta2-adrenoceptor agonist, developed specifically to treat the key symptoms of chronic obstructive pulmonary disease (COPD), breathlessness, cough and sputum. The dual sensory nerve modulation and bronchodilator effects of sibenadet have been demonstrated in initial dose-ranging studies of patients with COPD and large-scale clinical evaluation has now been completed. Sibenadet efficacy was determined by assessing symptomatic changes, as defined by the novel assessment tool, the Breathlessness, Cough and Sputum Scale (BCSS). The findings of two placebo-controlled studies are reported. These multicentre, double-blind, placebo-controlled studies recruited over 2000 patients with stable COPD, randomized to receive sibenadet (500 microg) or placebo, pressurized metered-dose inhaler (pMDI) (three times daily) for a period of 12 or 26 weeks. Diary cards were completed daily by patients throughout the study to record BCSS scores, peak expiratory flow (PEF), study drug and rescue bronchodilator usage, changes in concomitant medication and adverse events. The primary endpoints were defined as change from baseline to the final 4 weeks of the treatment period in mean BCSS total score, and forced expiratory volume in one second (FEV1) measured 1 hour after administration of the final dose of study drug and expressed as a percentage of the predicted FEV1. In addition, clinic assessments were made to determine changes in pulmonary function, health-related quality of life, perception of treatment efficacy and adverse events. Despite initial improvements in mean daily BCSS total scores in patients receiving sibenadet, the difference in the change from baseline to the final 4 weeks of the treatment period between the two treatment groups was neither statistically significant, nor considered to be of clinical importance. Although marked bronchodilator activity was seen early on with sibenadet treatment, the duration of effect diminished as the studies progressed. Sibenadet use was not associated with any safety concerns. These studies, utilizing the novel BCSS, have clearly illustrated that, despite initial symptomatic improvement with sibenadet therapy, this clinical benefit was not sustained over the course of the study.

Administration, Inhalation↗
PubMed2002

Treatment of acute severe asthma and chronic obstructive pulmonary disease in Danish hospitals. Do national recommendations improve on the quality of the treatment?

Studies have demonstrated suboptimal treatment of acute severe asthma and chronic obstructive pulmonary disease (COPD). We examined the quality of treatment in Denmark and the effect of intervention, by publication of recommendations for standardised treatment. All 70 hospitals in Denmark with emergency facilities participated in a telephone questionnaire, examining treatment behaviours among house officers. The survey was repeated 3 years later, after publication of national recommendations for treatment of acute exacerbations of asthma and COPD. The response rate in both surveys was 100%. An insufficient handling of nebulisers, a huge variation in the delivered dose of bronchodilators and a suboptimal use of corticosteroids was found. A significant trend towards more liberate use of oxygen was seen in both asthma (3.2 l min(-1) versus 4.8 l min(-1), P<0.001) and COPD (1.5 l min(-1) versus 1.9 l min(-1), P = 0.047). Further, a huge difference in treatment behaviours was revealed from this survey The knowledge among house officers of basic principles of treatment was insufficient. Treatment behaviour was only moderately affected by national publication of detailed recommendations for treatment. This study indicates a need for implementing tools for quality control.

Acute Disease↗
PubMed2002

A proposal for a practical treatment guideline designed for the initial two-hours of the management of patients with acute severe asthma and COPD using the principles of evidence-based medicine.

We have proposed a clinical treatment guideline for the management of acute, severe asthma and chronic obstructive pulmonarydisease (COPD) using the principles of evidence-based medicine. The content is based upon practical clinical issues in need of consensus. A previous study has shown that this particular area is in serious need of quality control. Based on a strict 2 h time schedule with a unified treatment plan for both asthma and COPD, it is possible to secure for the patients a well-documented medical therapy promoting decision-making and clarification of the patient within this time limit. A summary of the statements is presented in a one-page, user-friendly format in order to cope with the clinician's need of having access to published evidence quickly and easily. A website (www.phanareth.dk or a website provided by Respiratory Medicine) has been established providing regular updates. A strategy for the implementation and the evaluation process has been planned after the publication of this paper. We believe this approach to be an important step towards an increase in the quality of guidelines and also a tool to make "guideline writers" aware of the responsibility of making their recommendations work.

Acute Disease↗
PubMed2000

[Utilization of anti-asthmatic drugs among Danish children in 1998].

INTRODUCTION: The aim of the study was to evaluate the use of anti-asthmatics among Danish children in 1998. METHODS: Patient specific data were collected on anti-asthmatics (ATC-group R03) prescribed for children aged 0-15 years in 1998. Data included a total of 381,557 prescriptions for 139,727 individuals. RESULTS: Anti-asthmatics were prescribed for 13.9% of all Danish children on one or several occasions in 1998. The highest one-year prevalence and incidence rate of drug use was found for children aged 0-2 years. Most children were exclusively treated with either a short acting beta 2-agonist (66.7%) or an inhaled steroid (6.5%). Only 26.2% received both types of anti-asthmatics. CONCLUSION: In conclusion, anti-asthmatics were predominantly prescribed for the youngest children. Most children were exclusively treated with a short acting beta 2-agonist in 1998, which is only recommended in the case of mild intermittent asthma.

Administration, Inhalation↗
PubMed1999

[Arterial puncture or pulse oximetry?].

Arterial puncture is the general accepted standard method for monitoring oxygen therapy in critically ill patients, but this technique is painful for the patient, has the potential of complications, and does not provide immediate continuous data. Pulse oximetry is a non-invasive method used to measure arterial oxygen saturation with a clinically acceptable accuracy of +/- 2%. Despite some limitations, pulse oximetry is considered to be reliable in most cases in detecting hypoxaemia and monitoring oxygen therapy in stationary units. The pulse oximeter can reduce the number of arterial punctures, personnel's time consumption, and limit oxygen abuse. Furthermore the new transportable and hand-held pulse oximeters offer new possibilities for continuous 24 hour monitoring of oxygen saturation also out of hospitals. The pulse oximeter can optimize monitoring patients' oxygen saturation in the stationary units, however, arterial puncture will remain the most reliable method in the assessment of hypoxaemia and hypercapnia, especially in acute situations.

Arteries↗
PubMed1999

Reversible and irreversible airflow obstruction as predictor of overall mortality in asthma and chronic obstructive pulmonary disease.

The importance of reversible airflow obstruction to the prognosis of asthma and chronic obstructive pulmonary disease (COPD) is not clear. We tested the hypothesis that reversibility to corticosteroid and bronchodilator is not an independent predictor of prognosis, but merely reflects a component of the maximal attainable lung function, which is the best spirometric predictor of survival. During a 6-yr period (1983-1988), 1,586 subjects with asthma or COPD underwent standardized bronchodilator and corticosteroid reversibility tests at a chest clinic in Copenhagen. The vital status was obtained by September 1997. The relationship between mortality and age, gender, smoking, FEV1, and reversibilities was examined by Cox proportional hazards analyses. Of 1,586 subjects, 850 had died before September 1997. Age, smoking, and FEV1 were significant predictors of mortality. After controlling for baseline FEV1, bronchodilator and corticosteroid reversibility were significantly associated with better survival. However, after controlling for best FEV1 all reversibilities became nonsignificant and nonpredictive. The combined use of corticosteroid and bronchodilator reversibility in survival analyses is a novel approach, and we have shown that both contribute to survival prediction to the extent that they modify FEV1. However, reversibility per se does not influence survival in subjects with moderate to severe asthma or COPD.

Asthma↗
PubMed1998

[Allergic rhinoconjunctivitis treated with intramuscular injection of glucocorticoid].

Effects and side effects of injectable depot steroid in the treatment of allergic rhinoconjunctivitis (hay fever) are described. A few controlled studies have shown injectable steroids to be superior to the effect of placebo and locally applied steroid. Over a period of 10 years from 1984-95 only 26 registered side effects were reported to the central Danish register for side effects of drugs (Laegemiddelstyrelsens Bivirkningsregister). Only eight concerned subcutaneous atrophy and in two cases the cutaneous changes persisted. Based on registration of number of treatments in the county of Funen 1996, it is estimated that the use of injectable depot steroids for treatment of hay fever accounts for about 535,000 DDD (defined daily doses corresponding to about 33,000 treatments per year). We conclude that the use of injectable corticosteroids in the treatment of hay fever is common and effective and side effects are very rare. However, injectable corticosteroids should only be used when conventional treatment is not sufficient to control symptoms.

Betamethasone↗
PubMed1997

[Treatment of severe acute exacerbation of asthma and chronic obstructive lung disease. An interview study].

UNLABELLED: A telephone survey was conducted of all the 71 Danish hospitals with the capacity to receive acutely ill medical patients. The purpose was to register treatment regimes used in acute asthma and exacerbations in chronic obstructive pulmonary disease (COPD). The house officer on duty was interviewed and questioned about the use of nebulizers, oxygen therapy, bronchodilators, steroids, theophyllins and monitoring of the patient's condition. The physician survey was supplemented by a smaller survey among emergency room nurses about nebulizing systems. The answers showed inadequate knowledge of nebulizing systems. There was a noticeable variation in the dosing of oxygen and in the dosing of bronchodilators and steroids. beta 2-agonist treatment by nebulizer differed with a factor 14 in dose. The majority of the physicians had no specific parameters for monitoring severity of disease. CONCLUSION: There is a need for improvement of the knowledge of nebulizing systems, including specific knowledge of the appropriate use of propellant gasflow and time of nebulizing for optimum performance of the used nebulizer. Divergent answers from the nurses and the physicians show the need for interdisciplinary instruction. The noticeable variation in treatment in this Danish survey displays a need for quality control in terms of concise guidelines for medical therapy in acute exacerbations of asthma and COPD and guidelines for monitoring of the response to the treatment. A suggestion for a treatment regime is proposed.

Acute Disease↗
PubMed1996

[Self-administration of adrenaline aerosol in anaphylactic reactions after insect stings].

A serious allergic reaction after an insect sting is wellknown source for concern and anxiety. Patients with known hypersensitivity to insect stings are usually equipped with an adrenaline self-injection kit by an allergologist. In Denmark a new device for self-medication of adrenaline was approved in 1994, the adrenaline aerosol spray, Adrenalin Medihaler. The article is based on former studies and experiences, related to the usage of an adrenaline aerosol spray for the treatment of anaphylactic reactions after an insect sting. We conclude that adrenaline aerosol treatment should play an important role as emergency treatment for anaphylactic reactions after insect stings, and in most cases can replace the use of adrenalin self-injection kits. Adrenaline aerosol self-treatment could have an important beneficial effect helping to avoid exacerbation of the initial symptoms after insect venom exposition, such as bronchial obstruction and laryngeal oedema.

Aerosols↗
PubMed1994

[Theophylline treatment of irreversible, chronic obstructive pulmonary disease].

Even though the clinical efficacy is not well established, theophylline is commonly prescribed as a second or third line drug after inhaled beta 2-agonists and corticosteroids for patients with chronic obstructive pulmonary disease (COPD). The therapeutic index is narrow, and therefore theophylline is often given in a "safe standard dose", e.g. 300 mg b.i.d. We studied the long-term effect of sustained-release theophylline 300 mg b.i.d. over four weeks in 48 patients with severe irreversible COPD (FEV1: 0.99 +/- 0.45 l, FVC: 2.21 +/- 0.68 l) in a randomized, double-blind crossover study. During theophylline treatment there was significant improvements in dyspnoea score (p < 0.001) and morning peak-flow (p < 0.05). In spite of this, there was no significant change in the patients' "sense of well-being" or their daily use of inhaled beta-agonist. Spirometric tests or arterial blood gas values did not change significantly either. It is concluded that addition of theophylline in a "safe standard dose" (i.e. 300 mg b.i.d.) has only limited value in these patients.

Adult↗
PubMed1994

Clinical efficacy and safety of Turbuhaler as compared to pressurized MDIs-beta 2-agonists.

Beta 2-agonists are one of the cornerstones in the management of patients with obstructive lung diseases. The Turbuhaler containing terbutaline has been available in several countries for a few years only but has proven to have effects comparable to those of the conventional metered dose inhaler (MDI) and other powder inhalers in the treatment of obstructive lung diseases. Even in acute severe asthma, treatment with terbutaline via the Turbuhaler has proven as effective as treatment with the conventional MDI in combination with the 750ml spacer. These results indicate that the conventional MDI containing terbutaline can be exchanged by the Turbuhaler for most clinical purposes. Thereby this new method of treatment can contribute to the reduction of chlorofluorocarbon (CFC) pollution of the atmosphere. Furthermore, CFC-provoked bronchoconstriction can be avoided.

Aged↗
PubMed1994

Bronchodilating effect of terbutaline powder in acute severe bronchial obstruction.

The bronchodilating effect of terbutaline dry powder inhaled via Turbuhaler was compared with terbutaline inhaled via a conventional, chlorofluorocarbon (CFC) inhaler and Nebuhaler (750 ml spacer) in 68 consecutive patients attending the emergency department with acute severe bronchial obstruction. The study was of an open, randomized, parallel group design with one study day. Patients were treated with 2.5 mg of terbutaline 15 min apart, either as dry powder via Turbuhaler or with a CFC inhaler in conjunction with Nebuhaler. Data from 62 patients were analyzed. The mean baseline FEV1 values were 0.81 L (SD, 0.64; range, 0.14 to 2.74 L) in the Turbuhaler group (n = 33), and 0.90 L (SD, 0.90; range, 0.27 to 2.60 L) in the Nebuhaler group (n = 29). The mean increases in FEV1 from baseline were 0.40 L (SD, 0.40; range, 0.06 to 2.36 L) and 0.21 L (SD, 0.25; range, -0.05 to 0.95 L) 10 min after the last inhalation via Turbuhaler and Nebuhaler, respectively. The difference between mean values of the increase in FEV1 after terbutaline treatment with Turbuhaler and the CFC inhaler and Nebuhaler was statistically significant (p = 0.0004, ANOVA). This study showed that inhalation of terbutaline via Turbuhaler produced a significantly greater increase in FEV1 compared with the same dose of terbutaline administered via the CFC inhaler and Nebuhaler in patients attending the emergency department with acute severe bronchial obstruction.

Acute Disease↗