A standardised comparison of chest and percutaneous drainage catheters to evaluate the applicability of the 'French' sizing units.

A variety of medical specialities undertake percutaneous drainage but understanding of device performance outside radiology is often limited. Furthermore, the current catheter sizing using the "French" measurement of outer diameter is unhelpful; it does not reflect the internal diameter and gives no information on flow rate. To illustrate this and to improve catheter selection, notably for chest drainage, we assessed the variation of drain performance under standardised conditions.