EXECUTIVE SUMMARY
Laminar flow ventilation is used in modern orthopaedic operating theatres to reduce the number of infective organisms present in the air, which may lead to post-operative wound infection. This is of particular significance in jointprosthesis surgery, where delayed and deep-seated post-operative infection
may result in poor patient outcomes and substantial costs, both to patients and health care providers. To be most effective, key operating theatre staff should wear body exhaust suits whilst working in the ultraclean environment.

Laminar flow ventilation was first pioneered by Charnley in the 1960s and 1970s and resulted in a marked reduction in post-operative wound infection. As it was introduced in conjunction with other strategies to reduce sepsis, itwas not until the results of trials conducted in the 1980s by Lidwell became available, that laminar flow ventilation became widely adopted in orthopaedic operating theatres. Studies were confined to total hip or knee surgery and results demonstrated that the lower the count of airborne bacteria, the lower the sepsis rate.

Much of the more recent literature is predicated on Lidwell’s findings, examining the different types of laminar flow ventilation available, the role of prophylactic antibiotics and the effectiveness of body exhaust suits. A relatively small amount of work has been published on the relationship between the number of airborne bacteria and the post-operative wound infection rate. Two recent studies, involving the move from existing older conventional theatres to modern ultraclean facilities have indicated that the role of laminar flow ventilation in the context of the use of modern prophylactic antibiotics may be marginal.

In Australia, no current standards or guidelines indicate that laminar flow ventilation must be adopted in any operating theatres, however in instances where laminar flow ventilation is installed, standards prescribe the operation and testing of such ventilation.

INTRODUCTION
Laminar flow or ultraclean ventilation is used in modern orthopaedic operating theatres to reduce the number of infective organisms present in the air, which may lead to post-operative wound infection. A continuous flow of highly filtered ‘bacteria-free’ air is recirculated under positive pressure into the
operating field and air contaminants generated during surgery are removedfrom the site. This is of particular significance in joint prosthesis surgery,where delayed and deep-seated post-operative infection may result in poor patient outcomes and substantial costs, both to patients and health care providers.