Laser plume containment during flexible transnasal laryngoscopy

Evaluation of face shields used during aerosol generating procedures

Transnasal flexible laryngoscopy is considered an aerosol generating procedure. A negative pressure face shield (NPFS) was developed to control aerosol from the patient during laryngoscopy. The purpose of this study was to determine the effectiveness of the NPFS at controlling virus aerosol compared to a standard disposable plastic face shield. The face shields were placed on a simulated patient coughing machine. MS2 bacteriophage was used as a surrogate for SARS-CoV-2 and was aerosolized using the coughing machine. The aerosolized virus was sampled on the inside and outside of the face shields. The virus aerosol concentration was not significantly different between the inside and outside of the traditional plastic face shield (p = 0.12). However, the particle concentrations across all particle sizes measured were significantly decreased outside the face shield. The virus and particle concentrations were significantly decreased (p < 0.01) outside the NPFS operating at a flow rate of 38.6 L per minute (LPM). When the NPFS was operated at 10 LPM, virus concentrations were not significantly different (p = 0.09) across the face shield. However, the number particle concentrations across all particle sizes measured were significantly different (p < 0.05).

Diagnostic and surgical innovations in otolaryngology for adult and paediatric patients during the COVID-19 era

During the Coronavirus Disease 2019 (COVID-19) pandemic, otolaryngology has been shown to be a high-risk specialty due to the exposure to aerosol-generating physical examinations, procedures and surgical interventions on the head and neck area, both in adult and paediatric patients. This has prompted the issue of updating the guidelines by International Health Authorities in the Ear Nose and Throat (ENT) field and, at the same time, has stimulated engineers and healthcare professionals to develop new devices and technologies with the aim of reducing the risk of contamination for physicians, nurses and patients.

Methods

A review of the literature published on PubMed, Ovid/Medline and Scopus databases was performed from January 01, 2020 to December 31, 2021.

Results

73 articles were eligible to be included, which were subdivided into 4 categories: ("Artificial Intelligence (AI)"; "Personal Protective Equipment (PPE)"; "Diagnostic tools"; "Surgical tools").

Conclusions

All of the innovations that have been developed during the COVID-19 pandemic have laid the foundation for a radical technological change of society, not only in medicine but also from a social, political and economical points of view that will leave its mark in the coming decades.

Laser plume containment during flexible transnasal laryngoscopy

Objective

To evaluate a negative pressure microenvironment designed to contain laser plume during flexible transnasal laryngoscopy.

Methods

The Negative Pressure Face Shield (NPFS) was previously reported as well tolerated with initial use on 30 patients. Diagnostic transnasal laryngoscopy was performed on an additional 108 consecutive patients who were evaluated by questionnaires and sequential pulse oximetry. Further study addressed operative transnasal potassium‐titanyl‐phosphate (KTP) laser laryngoscopy with biopsy done on four patients employing the NPFS.

Results

The previously described NPFS version 3 (v.3), a transparent acrylic barrier with two anterior instrumentation ports, was modified by repositioning the side suction port closer to the level of the nose and deepening the lateral sides, squaring off the lower projection. A post‐procedure questionnaire employing a 5‐point Likert scale ranging from no symptoms (rating of 1) to intolerable (rating of 5) identified excellent patient tolerance of the new design (v.4), among 22 patients evaluated and similar in the comparison to the 116 patients using version 3. Among the 138 patients analyzed, only one patient rated the experience as greater than “mild claustrophobia.” 100% of patients answered either “none” or “mild” to the pain and shortness of breath questions. The NPFS (v.4) was then successfully used in four patients for laser laryngoscopy with biopsy of laryngeal papilloma (3/4) and hemorrhagic polyp (1/4). Post‐procedure questionnaire identified no shortness of breath (4/4), no claustrophobia (4/4), no pain (4/4) and no significant changes in pulse oximetry during use.

Conclusion

Extensive experience in performing diagnostic laryngoscopy with the NPFS directed design changes leading to successful use for transnasal flexible laser laryngoscopy with biopsy in a negative pressure microenvironment.

Level of Evidence

Level 2b (Cohort Study).