Reduction of germs in the nose before surgeries using dye (methylene blue) and activation by light.

Zusammenfassung der Studie

The "antimicrobial photodynamic therapy" (aPDT) is a method to inactivate pathogens using light and a dye (in our study, methylene blue and the germ-reducing agent chlorhexidine added for the dye's durability). In our research project, we aim to find out whether antimicrobial photodynamic therapy (aPDT) can reduce the microbial load in the nose prior to surgical procedures, in addition to standard disinfectants. This is with the aim of reducing the risk of wound infections. The treatment is carried out as part of a planned operation at the clinic for oral, maxillofacial, and head and neck surgery under general anesthesia (full anesthesia) before the actual surgery. The participants are already asleep and do not notice the treatment. To investigate the additional benefit of antimicrobial photodynamic therapy (aPDT), participants will be randomly assigned (according to a coin toss) to a control group and a study group. Both groups receive the same treatment with the difference that in the control group the light source is not turned on. Thus, the dye is not activated, but the germ-reducing agent chlorhexidine still works. To investigate the microbial load of the nasal cavity, a nasal swab will be taken before and after the treatment using a cotton swab (nasal swab). A further nasal swab will be taken after 2 weeks to investigate the long-term effect of the treatment (which germs have regrown, which have not). Additionally, participants will be questioned on the first day after surgery and as a control after 2 weeks using a questionnaire by one of our doctors regarding possible side effects. The duration of the study is 2 weeks. Participants do not have any additional appointments besides the regular follow-up appointments after the planned surgery.

(BASEC)

Untersuchte Intervention

The nasal cavity is colonized by many microorganisms. Most are harmless. However, pathogenic germs can also enter through the nasal cavity, which can later lead to respiratory infections or, in the post-operative phase, to wound infections. The "antimicrobial photodynamic therapy" (aPDT) is a method to inactivate pathogens using light and a dye (in our study, methylene blue and the germ-reducing agent chlorhexidine added for the dye's durability).

In our research project, we aim to find out whether antimicrobial photodynamic therapy (aPDT) can reduce the microbial load in the nose in addition to the germ-reducing agent chlorhexidine. This is with the aim of reducing the risk of wound infections.

In the study, the approved medical device "Steriwave" from Ondine Biomedicals is used. "Steriwave" is a device for treating the nose with red light and a dye (methylene blue). The device has been approved by the competent authority in Switzerland for treating the nose against pathogens. Methylene blue is the dye used by Steriwave and is an approved medical product in Switzerland that is used according to the authorization.

The Steriwave device is already routinely used in other countries (e.g., Canada). The University Hospital Zurich will test the device in the study for the reduction of nasal germs before surgical procedures and may subsequently incorporate it into routine practice.

To examine the difference between treatment with "antimicrobial photodynamic therapy" (dye including chlorhexidine and light) compared to chlorhexidine and the dye not activated by light, participants will be divided into two groups. The difference in treatment is that in the control group, the red light produced by the "Steriwave" device is not activated. Thus, the results of the study group with light activation can be compared with those of the control group without light activation (controlled study).

Participants will be randomly assigned to the two groups (randomized).

This randomized controlled study (random allocation of participants) will be conducted at the University Hospital Zurich in the clinic for oral, maxillofacial, and head and neck surgery. A total of 208 people will participate.

In addition to the study information and explanation, a total of three appointments will take place, with the first two occurring during the hospital stay.

The first appointment takes place at the University Hospital during the preparations for the planned surgery at the clinic for oral, maxillofacial, and head and neck surgery. The participants are already under general anesthesia (full anesthesia) and therefore do not notice anything about the treatment.

Three minutes before the treatment with the "Steriwave" device, a swab from the front of the nose (both nostrils) is taken. Then, the inside of the nose is coated with the dye and the light guides are inserted into the nose. In the study group, the light activation lasts for two minutes, before the process is repeated (re-coating the inside of the nose and activating the light for 2 minutes). In the control group, there is no light activation (2 minutes wait followed by re-coating the inside of the nose with the dye). After five minutes, a nasal swab is taken again from all participants.

Both swabs (three minutes before and five minutes after) will be analyzed in the laboratory for the presence of germs and their number. The results can then be compared between the control group (no light activation) and the study group (light activation) to investigate the additional germ-reducing effect of the light treatment.

The second appointment takes place while still in the hospital and includes a questionnaire regarding possible side effects by one of our investigational doctors.

The third appointment takes place 14 days after the treatment as part of the regular follow-up after the planned surgical procedure. In this appointment, in addition to a new questionnaire on side effects (same questions as in the second appointment), a third nasal swab will be taken. This will examine whether there is still a reduction in germs or a change in the microbial composition in the nose as a result of the treatment after 14 days.

For all participants, the study lasts 14 days. No additional appointments are necessary for study participation. The study appointments are scheduled to be conducted together with the follow-up appointments after the surgery at the clinic for oral, maxillofacial, and head and neck surgery.

(BASEC)

Untersuchte Krankheit(en)

The nasal cavity is colonized by many microorganisms. Most are harmless. However, pathogenic germs can also enter through the nasal cavity, which can later lead to respiratory infections or, in the post-operative phase, to wound infections.

(BASEC)

Sponsor

Klinik für Mund- Kiefer- und Gesichtschirurgie Universitätsspital Zürich

(BASEC)

Name der bewilligenden Ethikkommission (bei multizentrischen Studien nur die Leitkommission)

Ethikkommission Zürich

(BASEC)

Datum der Bewilligung durch die Ethikkommission

26.01.2024

(BASEC)

Ergebnisse der Studie