One of the problems with suicide prevention programmes is that suicide is a rare event, and it's impossible to know how successful such programmes are because absence of suicide generates no data. Writing in QJM (2004;97: 677-80), a psychiatrist from New York says that many suicidal individuals are recognised and successfully treated, but people who are really determined to kill themselves will do so, despite the best efforts of healthcare professionals.

Performing a lung biopsy, even guided by computed tomography, is fraught with anxiety because of the high risk of puncturing the lung or causing a bleed. A complex review of 660 lung biopsy procedures identified a high rate of pneumothorax (23%) and a haemoptysis rate of 4%. The incidence of pneumothorax was inversely related to the size of the lesion being biopsied and the experience of the radiologist. The risk of bleeding was inversely related to the size of the lesion and pleural effusion (Chest 2004;126: 748-54).

In an attempt to reduce clot formation inside artificial prosthetic blood vessels, scientists experimented with lining the inside of the polyurethane vessels with human vascular cells. They found that seeding with a mixture culture from smooth muscle cells and fibroblasts, and then perfusing the prostheses under a pulsatile flow for two hours, resulted in improved …