A breath of fresh air

Lung cancer remains the leading cancer in the developed world. It is usually inoperable at presentation but there is new optimism regarding chemotherapy in non-small-cell lung cancer after the publication of a meta-analysis suggesting that cisplatin-based chemotherapy, in combination with surgery, radical radiotherapy, or best supportive care, results in significant prolongation of survival (BMJ 1995; 311: 899). In chronic obstructive pulmonary disease (COPD) non-invasive ventilation is increasingly being used in patients with acute respiratory failure. The benefits have been shown in a recent randomised controlled trial, the outcome measures being needed for endotracheal intubation, duration of hospital stay, and mortality (N EnglJ Med 1995; 333: 817). Obstructive sleep apnoea, which affects up to 5% of the general population, is associated with an increased risk of road traffic accidents. The untreated condition impairs simulated driving performance to about the same extent as a blood alcohol of 95mg/dL (George). This risk is reduced by treatment with nasal continuous positive airways pressure (CPAP) (Chest 1996; 1096: 1470). A recent study has shown a reduction in fibrinogen levels on nasal CPAP (Am J Respir Crit Care Med 1996; 153: 1972). After the controversy surrounding the oral contraceptive pill, it has now been established that the risk of venous thromboembolism, including primary pulmonary embolism, is also increased with postmenopausal hormone-replacement (Grodstein). Diagnosis of pulmonary embolism may be aided by spiral computed tomography, (Thorax 1996; 51: 23). Concern regarding multidrug resistant tuberculosis has continued to increase (Lancet 1996; 348: 928). The understanding of the molecular basis of resistance, particularly to isoniazid, is improving and continuing advances in PCR technology are facilitating rapid and accurate diagnosis (Condos). In pulmonary sarcoidosis, a study has suggested that, in patients not requiring steroid treatment initially who do not show spontaneous radiographic improvement during 6 months of observation, prolonged steroid treatment thereafter, over at least 18 months, results in a better functional outcome than selective treatment (Gibson). There has been much interest in the adverse respiratory health effects of respirable particles (PM10: <10 gm diameter), ozone, sulphur dioxide, oxides of nitrogen, and acid aerosols. The main source of particulate pollution is diesel-vehicle exhausts. Both respiratory and cardiovascular mortality (and morbidity) are increased by acute exposure to PM~0 particles even at current ambient levels. Pollution, however, does not seem to be responsible for the doubling in incidence of asthma over the past 20 years. Although established asthma is made worse by