Surgical Helmet System hoods in joint arthroplasty may not completely sterile after it has been applied: study

The incidence of prosthetic joint infection (PJI) is increasing, coincident with the rising volume of joint arthroplasty being performed. With recent controversy regarding the efficacy of surgical helmet systems (SHS) in pre venting infection, the focus has turned to the correct donning techniques and usage of surgical hoods. McAleese et al conducted a study to compare the bacterial contamination of the operating surgeon’s gloves after two common donning techniques of SHS hoods.

The study was conducted at ‘Tallaght University Hospital, Dublin, Ireland’. It has been published in ‘Arthroplasty’ journal.

The bacterial contamination rate was quantified using colony-forming units (CFUs), with 50 trials per formed per donning technique. Samples were cultured on 5% Columbia blood agar in ambient air at 37 °C for 48 h and all subsequent bacterial growth was identified using a MALDI-TOF mass spectrometer. In Group 1, the operating surgeon donned their colleague’s hood. In Group 2, the operating surgeon had their hood applied by a non-scrubbed colleague. After each trial, the operating surgeon immediately inoculated their gloves onto an agar plate. The immediate sterility of 50 SHS hoods was assessed at two separate zones—the screen (Zone 1) and the neckline (Zone 2).

Key findings of the study were:

• There was no significant difference in contamination rates between the two techniques (3% vs. 2%, P=0.99) or between right and left glove contamination rates.

• Immediately after donning, 6/50 (12%) of SHS hoods cultured an organism.

• Contamination rates at both the face shield and neckline zones were equivalent.

• The majority of bacteria cultured were Bacillus species.

The authors concluded that – “We found no statistically significant difference between the bacterial contamination rates of the operating surgeon’s gloves using two common techniques of SHS hood application. These trials were performed under laminar airflow with late fan activation. We advise that extreme care should be exercised when the operating surgeon assists donning a surgical colleague to negate the risk of inadvertent contamination. Importantly, based on our results, the SHS hood should not be presumed to be completely sterile after it has been applied and we recommend against adjusting it intraoperatively. Further studies examining the clinical significance of these results are warranted. Research comparing different donning techniques using different brands of gloves and sterile hoods may further enlighten this area.”

Further reading:

Surgical helmet systems in total joint arthroplasty: assessment of hood sterility and donning technique

McAleese et al

Arthroplasty (2023) 5:53

https://doi.org/10.1186/s42836-023-00212-4