Confusion in application of clean air systems to operating rooms
Confusion exists over the need to install air handling devices and systems in the operating rooms to supplement basic air filtering and distributing systems in surgical suites.
Surgeons, architects, and planners are being subjected to heavy pressure by surgical colleagues and by manufacturers to install so-called laminar flow enclosures in both newly planned and existing operating rooms, particularly for hip replacement surgery.
Difficulties in accumulating unbiased evidence on the possible clinical value of such installations are increased by emotional or defensive views, both pro and con. Neither the enthusiastic testimonial statements by some orthopaedic surgeons on the lower incidence of wound infection rates with such enclosures, nor the reaction against their use are the result of completely acceptable evidence at this time. Moreover, there is no known conclusive evidence to support the superiority of vertical over horizontal flow, or vice versa, nor that of unidirectional over turbulent flow, or vice versa, insofar as these parameters affect infection rates.
One fairly obvious point which seems to have escaped many proponents of special air chambers is the difference between operating rooms containing obviously dirty air and those with good ventilation, insofar as their need for a new system is concerned. Many operating rooms built 20 or more years ago, before current codes of federal. agencies guided the mechanical engineering installations, contain fairly dirty air and have poor ventilation. Other more recently built installations are poorly maintained, or function poorly. Visits to several British and European hospitals revealed that operating rooms in old. . .