Open tracheostomy remains one of the most common performed procedures for oncologic head and neck patients. Surgical site infections (SSI) are a common cause of morbidity, impair cosmetic outcomes and prolonged hospitalization (Ogihara et al., 2009; Zirk et al., 2018). In particular, the frequency of SSI is increased when a breach with damage to the mucosal barrier is communicated into the upper aerodigestive tract (Cannon et al., 2017). Concerning SSI of the head and neck, between 10% and 38% of patients undergoing laryngotracheal surgery experience an SSI (Torre, Paraboschi et al. 2019). In accordance with the Center for Disease Control (CDC), tracheostomy represents a procedure with clean-contaminated wounds and SSIs occur within 30 days after surgery (Cannon et al., 2017). Tracheostoma may be contaminated by the regional bacterial flora of the upper aerodigestive tract (Sittitrai and Siriwittayakorn 2018, Torre, Paraboschi et al. 2019), as well as by the bacterial flora of the skin (Sittitrai and Siriwittayakorn 2018), but a more common cause of surgical site infections remains the normal colonizing flora of the mouth and oropharynx (Torre, Paraboschi et al. 2019). While advancements in head and neck surgery have continued to develop, there remain limited data for prevention of SSI in the head and neck (Veve et al., 2018).

In literature, patients with a tracheotomy, both prior to or concurrent with ablative head and neck surgery, have a threefold increased risk for bacterial wound infection (Vander Poorten et al., 2020). In general, bacteria harvested from head and neck SSIs are polymicrobial (Bartella et al., 2017; Zirk et al., 2019). The bacterial flora of the upper respiratory/salivary tracts commonly contains Gram-positive organisms and facultative anaerobes, however Gram-negative bacilli may be isolated as well (Veve et al., 2017; Zirk et al., 2019). Nevertheless, the upper aerodigestive tract (UAT) remains a transition zone with constant exposition to inhaled and ingested microorganisms (Le Bars et al., 2017).

In particular for tracheostomy, bacterial colonies with Haemophilus, Pseudomonas, Corynebacterium, and Acinetobacter species have been reported, still further data is required to distinguish between colonization of the tracheostomy and purulent infections (Pérez-Losada et al., 2017) in order to accelerate the treatment and avoid further complications. Studies have investigated the most common infection pathogens found in postoperative wounds of surgical head and neck cancer patients (Brook and Hirokawa 1989), but most of these patients are undergoing tracheotomy. Regarding the fact that tracheotomy represents an additional breach of the skin and thereby an additional possibility for wound infections, it is important to reveal if the dominating bacteria is originating from the aerodigestive tract or are led forwarded from the oncologic wound and thereupon consider an adjustment in relation to antibiotic treatment in order to accelerate treatment.

The aim of this study is to reveal relevant risk factors for SSI of the tracheotomy of oncologic head and neck patients and furthermore to investigate a correlation of the tracheostomy wound to further wounds in the head and neck area, especially regarding the bacterial flora.