Walter McNicholas

Sleep has well-recognized effects on breathing, which in normal individuals have no adverse impact. These effects include a mild degree of hypoventilation with consequent hypoxaemia and hypercapnia, and a diminished responsiveness to respiratory stimuli. However, in patients with chronic lung disease such as chronic obstructive pulmonary disease (COPD), these physiological changes during sleep may have a profound effect on gas exchange, and episodes of profound hypoxaemia may develop,...

Some diagnostic examples

Most books describe the typical features of each condition, and it is often difficult for the clinician to relate the rather dry descriptions to the particular individual in the consulting room. This section describes the diagnostic problems in five real patients as they presented to the author. They are by no means inclusive of all the situations that may arise, but are intended to illustrate the need for objective assessment in order to deliver appropriate therapy for conditions that will...

What is the role of antileukotriene drugs in COPD

There are no published studies on the effects of leukotriene receptor antagonists or 5'-lipoxygenase inhibitors in COPD. There is evidence for increased formation of leukotriene B4 (LTB4) in COPD patients 10 , suggesting that inhibition of LTB4 synthesis by a 5'-lipoxygenase inhibitor or blockage of LTB4-receptors on neutrophils by a receptor antagonist may be of potential benefit. Although a 5'-lipoxygenase inhibitor, zileuton, is available for the treatment of asthma in some countries, its...

Wisia Wedzicha

Exacerbations of chronic obstructive pulmonary disease COPD are an important cause of the considerable morbidity and mortality found in COPD and an important cause of hospital admission 1 . Some patients are prone to frequent exacerbations that have considerable impact on quality of life and activities of daily living 2 . COPD exacerbations are also associated with increased airway inflammatory changes 3 that are caused by a variety of factors such as viruses, bacteria and possibly common...

Drug delivery in COPD

By analogy with asthma, a disease that affects all airways, it has been presumed that the inhaled route of delivery is preferred for the treatment of patients with COPD. However, the disease process in COPD is predominantly in small airways and in the lung parenchyma, which may not be efficiently targeted by the inhalers designed to treat asthma. This may lead to the development of new inhaler devices with particles that have the optimal distribution for peripheral lung delivery. Furthermore,...

Wisia Wedzicha and Mike Pearson

Why is there a need for a variety of outcome measures in COPD Chronic obstructive pulmonary disease COPD is characterized by a progressive decline in lung function that leads to dyspnoea on exertion and eventually to death. However, there is considerable variability in the rate of decline of forced expiratory volume in 1 second FEVX in different patients. A number of guidelines have been produced for the management of COPD, including those from the European Thoracic Society 1 , American...

Should mucolytics be used routinely

Because mucus hypersecretion is a prominent feature of chronic bronchitis, various mucolytic therapies have been used to increase the ease of mucus expectoration, in the belief that this will improve lung function. Stopping smoking is the most effective way to reduce mucus hypersecretion. Anticholinergics may decrease mucus hypersecretion, although most studies have failed to show an effect of inhaled anticholinergics on mucociliary clearance. b2-agonists and theophylline may improve mucus...

Info

53 Coakley JH, Nagendran K, Ormerod IE, Ferguson CN, Hinds CJ. Prolonged neurogenic weakness in patients requiring mechanical ventilation for acute airflow limitation. Chest 1992 101 1413-16. 54 Bott J, Carroll MP, Conway JH etal. Randomised controlled trial of nasal ventilation in acute ventilatory failure due to chronic obstructive airways disease. Lancet 1993 341 1555-7. 55 Brochard L, Mancebo J, Wysocki M etal. Noninvasive ventilation for acute exacerbations of chronic obstructive pulmonary...

Protease inhibitors

Elastase Half Life Concentration

Emphysema may result from an imbalance between excessive protease activity and deficient endogenous antiproteases Fig. 11.5, Table 11.2 . A logical Fig. 11.5 Imbalance between proteases and antiproteases in chronic obstructive pulmonary disease COPD . Fig. 11.5 Imbalance between proteases and antiproteases in chronic obstructive pulmonary disease COPD . Neutrophil elastase inhibitors ICI 200355, ONO-5046 Cathepsin inhibitors suramin Matrix metalloproteinase inhibitors batimastat, marimastat,...

What are the essential components of pulmonary rehabilitation

A comprehensive rehabilitation programme consists of different components. The literature reports usually include the following elements exercise training, specific limb training, respiratory muscle training, education, nutritional therapy, and psychosocial intervention. While everybody has the feeling that a multidisciplinary treatment is needed in some patients, there is no evidence yet that all components of rehabilitation are equally effective in reducing the level of disability or...

PaO2 between 73 kPa and 8 kPa 55 mmHg and 60mmHg

The range of PaO2 between 7.3 and 8 kPa 55 mmHg and 60 mmHg remains a grey area. From the MRC and NOT Trial, it is not clear whether LTOT has a beneficial effect on prognosis for these patients. This question was addressed by a randomized controlled trial in 135 Polish patients with COPD 4 . These patients had a PaO2 between 7.4kPa 55.5 mmHg and 8.7kPa 65.3 mmHg , with mean PaO2 8 kPa 60 mmHg . LTOT, over at least 3 years, was not associated with a survival benefit, and there was no difference...

Arterial oxygen tension PaO2 less than 73 kPa 55 mmHg

A PaO2 of up to 8kPa 60mmHg was the entry criterion for PaO2 for the MRC study 1 . The main entry criterion for PaO2 for the NOT Trial was a PaO2 below 7.3 kPa 55 mmHg , although patients with a PaO2 of up to 8 kPa 60 mmHg were included if they also had oedema, secondary polycythaemia, or significant pulmonary hypertension 2 . The mean PaO2 of patients entering both studies was 6.8 kPa 51mmHg . The widely used cut-off PaO2 of 7.3 kPa 55 mmHg for the prescription of LTOT in guidelines therefore...