An expansible cannula: a new technique for chest drain insertion.

The insertion of a chest drain into the pleural space is a common procedure used by many specialties. The commonly used device is a prepacked, sterile plastic tube with its own central metal trocar. Complications may arise during its insertion, with the occasional penetration of intrathoracic and upper abdominal organs. As most chest drains are inserted by junior and relatively inexperienced doctors, it is therefore imperative that a simple, safe, and effective technique of insertion is found. A device has been developed that consists of a 5 cm conical length of an expansible cannula, made from rolled metal foil, which when inserted into the chest reaches only a few millimetres within the pleura. When an expander tube, 10 mm in diameter, is passed through the device from its proximal end the conical tube is distended into a hollow cylindrical one, through which a standard Portex chest catheter is passed. The whole appliance is then removed over the end of the tube, leaving the drain in situ. The efficacy of this unique device has been tested in a pilot study in 22 patients. There have been no complications.