[Tilting at WIP windmills in the OR: laminar flow might be harmful]

The World Health Organization has published a new guideline for the prevention of surgical site infection (SSI), according to which laminar airflow systems should not be used to reduce the risk of SSI in the OR. The Dutch Health Care Inspectorate has, on the other hand, published a directive demanding laminar airflow in most operation rooms in Dutch hospitals. This directive is based on an evidence-based report from the Dutch Working Group on Infection Prevention (WIP). Since these guidelines are contradictory, the evidence presented in the WHO report as well as in the WIP report is evaluated in this article. The conclusion is that the WIP report used the available literature selectively, resulting in a favourable but false advantage for the laminar airflow system. The directive on laminar airflow should therefore be withdrawn and the WHO guideline should be implemented in Dutch hospitals.