Lidwell ultraclean air

Effect of ultraclean air in operating rooms on deep sepsis in the joint after total hip or knee replacement: a randomised study.

Lidwell OM, Lowbury EJ, Whyte W, et al. British medical journal (Clinical research ed.) 1982 · PMID 6805791 · doi:10.1136/bmj.285.6334.10

Question

Does operating in ultraclean (laminar flow) air reduce deep joint infection after hip and knee replacement?

Design

Multicentre MRC study in which each surgeon's operations were randomly allocated between ultraclean-air and conventional theatres.

Patients

Patients having total hip or knee replacement.

Intervention

Ultraclean air ventilation, with or without body-exhaust suits

Comparison

Conventional theatre ventilation

Primary outcome

Deep joint sepsis

Key result

Deep joint sepsis was roughly halved with ultraclean air and reduced further when whole-body exhaust suits were also worn; prophylactic antibiotic use was associated with lower sepsis, though this was not tested in a controlled way.

Limitations

Predates modern antibiotic protocols and implants; randomisation was by operation within surgeons rather than strictly at patient level, and the antibiotic effect was observational.

Impact on practice

It is the foundation for laminar flow theatres in UK arthroplasty and remains a frequently examined classic.