Impact of surgical lamp design on the risk of surgical site infections in operating rooms with mixing and unidirectional airflow ventilation: A numerical study

Abstract

Operating room (OR) ventilation plays an important role in mitigating the spread of bacteria-carrying particles (BCPs) and preventing the incidence of surgical site infections (SSIs). The use of surgical lamps in ORs is critical for patient safety and staff comfort. However, the surgical lamp serves as an obstruction in the ventilation airflow and also as a source of heat generation, which often creates a stagnant area under the lamp. Such a stagnant area is normally poorly ventilated, where a significant amount of BCPs can accumulate. As the lamp is usually positioned above the patient to illuminate the wound, the accumulation of airborne BCPs under the lamp leads to a high risk of infections and constitutes a threat to patient safety. Therefore, we proposed an innovative design of the surgical lamp, that is, the fan-mounted surgical lamp. The performance of this new design of lamp was compared with the conventional closed-shape lamp under two ventilation strategies: mixing and unidirectional airflow (UDF) ventilation. To account for different working conditions, both the horizontal and 45° orientations were applied to the lamps. We employed numerical simulations to predict the BCPs contamination in the proximity of the surgical site, as it is directly related to the risk of SSIs. The results showed that the fan-mounted lamp considerably reduced the level of contamination under both ventilation strategies. Results also suggested that the contamination level cannot be effectively reduced by only adjusting the orientation of the closed-shape lamp under unidirectional airflow ventilation.