Obesity and the lung: 2. Obesity and sleep-disordered breathing.

As the prevalence of obesity increases in both the developed and the developing world, the respiratory consequences are often underappreciated. This review discusses the presentation, pathogenesis, diagnosis and management of the obstructive sleep apnoea, overlap and obesity hypoventilation syndromes. Patients with these conditions will commonly present to respiratory physicians, and recognition and effective treatment have important benefits in terms of patient quality of life and reduction in healthcare utilisation. Measures to curb the obesity epidemic are urgently required.

Prevalence of sleepiness in surviving drivers of motor vehicle collisions.

BACKGROUND: Although alcohol and recreational drugs are recognized as significant risk factors for motor vehicle collisions (MVC), the contribution of sleepiness alone is less clear. We therefore sought to identify the contribution of sleepiness to the risk of a MVC in injured drivers, independent of drugs and alcohol. METHODS: A prospective questionnaire and examination of sleep-related risk factors in drivers surviving MVC in a major hospital-based trauma centre was carried out. RESULTS: Forty of 112 injured drivers screened were interviewed, of whom approximately 50% had at least one sleep-related risk factor, 20% having two or more. Of the MVC deemed sleep-related by questionnaire, only 25% were identified by the Australian Transport Safety Bureau definitions. Shift work was the greatest sleep-related factor identified contributing to MVC. CONCLUSION: Sleepiness, particularly related to shift work, needs to be emphasized as a risk factor for MVC. Australian Transport Safety Bureau definitions of sleep-related MVC are too lenient.

Non-invasive positive pressure ventilation for acute respiratory failure: justified or just hot air?

Non-invasive positive pressure ventilation (NIV) is the provision of mechanical positive airway pressure ventilatory support through the patient's upper airway through mask interface. Conditions in which it has been shown to be effective are acute cardiogenic pulmonary oedema and acute hypercapnic exacerbations of chronic obstructive pulmonary disease. In such conditions, NIV is associated with reduced intensive care unit demands, a reduction in intubation rates, reduced health-care expenditure and improved survival. Other conditions, such as hypercapnia of other cause, hypoxaemic respiratory failure and acute asthma, have supportive, but less conclusive data. Indications, contraindications and guidelines for the use of NIV are discussed.

A possible case of pneumoconiosis in a limestone quarry worker.

BACKGROUND: A 43-year-old man presented with wheeze and shortness of breath. He had an occupational history of working in a limestone quarry. Pulmonary function testing revealed a mixed obstructive/restrictive defect. Chest X-ray revealed nodular shadowing throughout both lung fields. METHODS: Subsequent thoracoscopic lung biopsy was performed and histology of the nodules revealed a foreign body granulomatous reaction with numerous fluorescent particles seen under polarized light. There was no evidence of interstitial fibrosis. RESULTS: Energy dispersive X-ray analysis (EDXA) scanning confirmed that these particles contained calcium, aluminium and silicon and had a composition consistent with limestone. CONCLUSIONS: This case demonstrates a possible unusual reaction to inorganic dust particles without resultant fibrosis.