Surgical sites must be as clean as possible. And hospitals are doing everything they can to ensure that the possibility of infection is low. However, healthcare-associated infection is still a thing and cannot be fully prevented. Scientists from Oregon State University and the University of California now created a computer model, which revealed that some actual surgical equipment may be helping to spread harmful bacteria.
As you may imagine, the environment in the surgical room is strictly controlled. Ventilation systems are designed to remove bacteria and not to let them back in. However, sometimes warm-air blowers are used at the same time, to keep the patient at the same temperature. This results in disturbed air, which interferes with ventilation system. This new computer model revealed that squames are tiny, disc-shaped flakes of skin, can easily reach the surgical site and cause an infection, which is a huge problem. It is because ventilation system delivers a steady clean downdraft of wind, but it can be disturbed by other forced air devices. And, at the same time, even wearing gloves and masks cannot prevent some skin shedding.
Squames are perfect for some microbial skin colonizers such as Staphylococcus aureus. The environment in surgical rooms is clean, but about 2 % of patients will develop surgical site infections. 3 % of those are deadly. These deaths can even occur after surgeries that are completely not life threatening, making the situation even more tragic. Scientists created a model, in which a patient is getting a knee surgery. There were 3 million squames included in the simulation and at the beginning all of them were on the floor. It was revealed that without forced-air surgical equipment the ventilation system was capable of absorbing most of the squames without causing much of a disturbance. However, with the warm-air blower on, causing rising thermal plumes, squames were floating over the surgical table.
Scientists modelled 3 million squames – that was enough work for 1,600 processors. That is a lot of work – it took 2 million central processing unit hours. The part with the warm-air blower on took about 200 hours of dedicated parallel computing alone. Sourabh Apte, corresponding author of the study, said: “The numerical approach lacks any limitations from a theoretical point of view, but there is a lack of detailed experimental measurements of the 3D velocity ﬁeld in an operating room during a clinical trial”.
Real life experiments are difficult and that is where computer simulations excel. However, it remains to be seen what will be done with this knowledge. Hopefully, some other temperature control methods will be used instead of warm-air blowers.
Source: Oregon State University