key: cord-0814450-6keofkrn authors: Vahabzadeh‐Hagh, Andrew M.; Patel, Shiv H.; Stramiello, Joshua A.; Weissbrod, Philip A. title: Patient‐worn endoscopy mask to protect against viral transmission date: 2021-12-09 journal: Laryngoscope Investig Otolaryngol DOI: 10.1002/lio2.708 sha: 9a636af85526014505cef189439799edb745e3a4 doc_id: 814450 cord_uid: 6keofkrn OBJECTIVES: To design and evaluate patient‐worn personal protective equipment (PPE) that allows providers to perform endoscopy while protecting against droplet and airborne disease transmission. STUDY DESIGN: Single subject study. METHODS: Mask efficacy was evaluated using a cough simulator that sprays dye visible under ultra‐violet light. User‐testing was performed on an airway trainer mannequin where each subject performed the endoscopy with and without the mask in random orders. Their time to completion and number of attempts before successful completion were recorded, and each subject was asked to fill out a NASA Task Load Index (TLX) form with respect to their experience. RESULTS: The mask has a filtration efficiency of 97.31% and eliminated any expelled particles with the cough simulator. Without the mask, a simulated cough is visualized as it progresses away from the cough origin. Subjects who performed trans‐nasal endoscopy spent 27.8 ± 8.0 s to visualize the vocal cords for the no mask condition and 28.7 ± 13.6 s for the mask condition (mean ± SD, p > .05). There was no statistically significant difference found in the mental demand, physical demand, temporal demand, performance, effort, and frustration of endoscopy under the no mask and mask conditions (all p > .05). CONCLUSION: The designed PPE provides an effective barrier for viral droplet and airborne transmission while allowing the ability to perform endoscopy with ease. LEVEL OF EVIDENCE: 3 Laryngoscope, 2021. masks by infected patients. 3 Otolaryngology has proven to be one of the highest risk medical specialties in the present SARS-CoV-2 pandemic due to the high viral burden located in the nasal and upper aerodigestive tract with a risk ratio of 2.13, compared to other healthcare workers. [3] [4] [5] [6] The earliest reports of physician deaths during this pandemic were related to surgical exposure from otolaryngology procedures. 7 In the practice of otolaryngology, flexible trans-nasal endoscopy and rigid nasal endoscopy are essential diagnostic and therapeutic procedures. In 2014, Medicare patients alone underwent office based diagnostic laryngoscopy nearly 600,000 times. These endoscopic procedures, and others like it, have potential to become aerosolizing events which increase transmission of viral particles. Aerosolization can occur with a cough, sneeze, gag, or vocalization. Additionally, with more advanced office-based procedures such as nasal debridement, vocal fold injection augmentation, trans-nasal esophagoscopy, or laser ablation in the larynx, aerosolization events are not only inherent to the procedure itself, but also required as part of the laryngotracheal anesthesia preparation. Physicians were discouraged from performing elective endoscopic procedures due to COVID-19 exposure risk. 8 While the impact of this recommendation on clinical practice is unknown, it is feasible that it may have created delays in diagnosis and timely treatment. Endoscopists typically wear PPE appropriate to the clinical risk, but there is still concern of significant viral transmission due to close proximity to the patient during an aerosolizing event. 9 Similarly, higher room cleaning burden following aerosolizing events increases room turnover times, which further stresses the medical system by reducing service opportunities. 10 To date, there are only a few good options to limit the extent of spread of aerosolization by the patient in the outpatient setting during these types of procedures. One possible approach is reducing the extent of aerosolization of a cough or sneeze by limiting spread, thereby reducing potential for viral transmission. [11] [12] [13] [14] [15] A number of recent studies have begun to study patient worn PPE to assist with transmission reduction during procedures, however to date it is not clear that these devices are applicable to the outpatient setting and have not been tested with flexible endoscopic procedures. 16 Several PPE devices have been displayed in the literature that all create a barrier between the nose and mouth of the patient and the physician, usually in the form of a mask. [16] [17] [18] [19] [20] However, most of these solutions lack user-testing to suggest clinical applicability. Here, we present a simple PPE design that can be used for trans-nasal or trans-oral endoscopies, and provide data showing the effectiveness of the PPE and user experience. Such a device must be both clinically effective and not burdensome for successful adoption. Czech Republic), the nose cone components and a mold for the silicone valve were printed. The valve and components of the nose cone were then press fit into the hole at the center of the mask ( Figure 1C ). Filtration efficiency of the polypropylene sheet was done using a PortaCount Plus Model 8020 particle counter (TSI, Shoreview, MN). The material is inserted in a chamber that allows room air to pass through the material and enter the PortaCount to read out the number of particles/cc in the air sample. The protocol was modeled after filtration efficiency tests conducted in prior studies found in the literature. [21] [22] [23] [24] [25] A HEPA filter that comes with the machine was used as a control. The measured filtration efficiency was then compared to the measured filtration efficiency of 3M 1860 N95 found in literature using the same protocol for measuring filtration efficiency. 24 We deployed a single-subject study design to compare the trans-nasal endoscopy with and without the mask. For comparison, the time to completion, number of attempts before successful endoscopy, and completion of the NASA Task Load Index (TLX) Form were required from each study participant. Participant inclusion criteria included head and neck surgery residents who have been trained in trans-nasal endoscopy. A total of 10 residents were used in the study and served as their own control. Each resident was asked to perform trans-nasal endoscopy on an airway mannequin (7-Sigma, Minneapolis, MN) using a disposable Karl (Table 1) . 24 At the start of the COVID-19 global pandemic, routine procedures that exposed physicians to aerosolization became challenging and less safe to perform. Otolaryngologists have an increased risk of contracting a virus, such as SARS-CoV-2, due to the higher viral load in the nasal and upper respiratory tract. This is especially true for the delta strain which can achieve a 1000-fold higher viral load in the nasopharynx compared to the alpha strain of the first and second waves of the pandemic. Specifically, trans-nasal endoscopy is a procedure that puts endoscopists at risk of contracting COVID-19 because the patient's mouth and nose are exposed during the procedure and events such as coughing and sneezing commonly occur. It is important to note that such risk is also present outside the context of COVID-19 such as during the influenza season and therefore applicability of patient worn PPE extends beyond COVID-19. Here, we present a potential solution that creates a feasible barrier between the patient and endoscopist while providing a means of safely and easily doing the procedure. The endoscopy mask presented here effectively prevents the spread of aerosolized materials as shown by the cough simulation experiment. The overall material cost of the silicone, poly-lactic acid 3D printer filament, aluminum alloy, and polypropylene sheets is $0.45, indicating the mask does not pose expense barriers for clinical utilization. Furthermore, user-testing done on a high-fidelity mannequin shows that there is no statistically significant difference in task load and time of procedure between the masked and no mask condition. More advanced techniques to assess the protective capability of the endoscopic mask are required. Computational fluid dynamic models of masked and unmasked conditions could provide insight into spread of aerosol in 3D space. 36, 37 The spread of aerosol and droplets should also be assessed in in real time during a trans-nasal endoscopy using multiple optical particle counters at various locations in the procedure room. 38 by this mask. However, as they note as study limitations, the study design did not allow for identification of particle size below 30 μm and did not measure the presence of airborne particles. 16 This mask is a relatively inexpensive, one-time use design, reducing the risk of patient-to-patient transmission, but there is concern as to whether it can effectively block aerosolization events without a tight facial seal or fluid barrier. The COVID-19 pandemic is ongoing and has altered the efficiency and safety of office-based aerodigestive endoscopies by adding time between room use, reducing assisting personnel, and requiring negative pressure operating rooms. 41, 42 Thus, a feasible solution as demonstrated by the endoscopy mask should be further evaluated and implemented clinically to improve efficiency and safety for both the current pandemic, as well as future viral endemics. The results of our study show promise that the endoscopic mask can be used clinically in a disposable manner however, further testing is necessary to prove this. The next steps would include testing the endoscopy mask clinically and assess differences in the task load, time of procedure, and patient comfort between the masked and unmasked conditions. The endoscopy mask poses very little risk to patient safety; however, trials to assess the efficacy of its clinical implementation should be done expeditiously as the benefits far outweigh the risks from a safety, logistics, and financial perspective. The use of the patient worn endoscopy mask presented here provides a protective barrier between endoscopist and patient while maintain a similar user task load as compared to the no mask condition. While more work is required for validation clinically, study thus far is promising, and we propose that this device holds potential given its ease of use, low production cost, and reduced aerosol exposure during procedures. Effectiveness of precautions against droplets and contact in prevention of nosocomial transmission of severe acute respiratory syndrome (SARS) Medical masks vs N95 respirators for preventing COVID-19 in healthcare workers: a systematic review and meta-analysis of randomized trials. Influenza Other Respir Virus Respiratory virus shedding in exhaled breath and efficacy of face masks SARS-CoV-2 viral load in upper respiratory specimens of infected patients COVID-19 and the otolaryngologist: preliminary evidence-based review COVID-19 pandemic: effects and evidence-based recommendations for otolaryngology and head and neck surgery practice Letter: precautions for endoscopic Transnasal Skull Base surgery during the COVID-19 pandemic Flexible laryngoscopy and COVID-19 Impact of coronavirus (COVID-19) on otolaryngologic surgery: brief commentary Aerosol and surface stability of SARS-CoV-2 as compared with SARS-CoV-1 Aerosol emission and superemission during human speech increase with voice loudness Aerosol transmission of infectious disease Characterizations of particle size distribution of the droplets exhaled by sneeze Violent expiratory events: on coughing and sneezing Barrier enclosure during endotracheal intubation Endonasal instrumentation and aerosolization risk in the era of COVID-19: simulation, literature review, and proposed mitigation strategies Nasal endoscopy during the COVID-19 pandemic: mitigating risk with 3D printed masks The nose lid for the endoscopic endonasal procedures during COVID-19 era: technical note Negative pressure face shield for flexible laryngoscopy in the COVID-19 era Application of a modified endoscopy face mask for flexible laryngoscopy during the COVID-19 pandemic Correlation of respirator fit measured on human subjects and a static advanced headform Assessing real-time performances of N95 respirators for health care workers by simulated workplace protection factors Institution of a novel process for N95 respirator disinfection with vaporized hydrogen peroxide in the setting of the COVID-19 pandemic at a large academic medical center Can N95 respirators be reused after disinfection? How many times? Effects of ultraviolet germicidal irradiation (UVGI) on N95 respirator filtration performance and structural integrity Assessing the physiological relevance of cough simulators for respiratory droplet dispersion Assessment of respiratory droplet transmission during the ophthalmic slit lamp exam: a particle tracking analysis Assessment of healthcare worker protocol deviations and self-contamination during personal protective equipment donning and doffing Closed" supraglottic airway-guided intubation during the COVID-19 pandemic: a Glo germ follow-up Efficacy of slit lamp breath shields Break scrub to take that phone call? Exposure to a surrogate measure of contamination from simulated patients by emergency department personnel wearing personal protective equipment Simulation as a tool for assessing and evolving your current personal protective equipment: lessons learned during the coronavirus disease (COVID-19) pandemic Filtration efficiency, effectiveness, and availability of N95 face masks for COVID-19 prevention Filtration efficiency of hospital face mask alternatives available for use during the COVID-19 pandemic Flow dynamics and characterization of a >cough Computational fluid dynamics study on the influence of an alternate ventilation configuration on the possible flow path of infectious cough aerosols in a mock airborne infection isolation room Efficacy of slit lamp breath shields Innovations in otorhinolaryngology in the age of COVID-19: a systematic literature review Aerosolized particle reduction: a novel cadaveric model and a negative airway pressure respirator (NAPR) system to protect health care workers from COVID-19 Nasal endoscopy protocols in the era of COVID-19 Transnasal endoscopic skull base surgery during COVID-19 pandemic: algorithm of management in an Italian reference COVID center Patient-worn endoscopy mask to protect against viral transmission The authors would like to acknowledge Alex Grant from the UCSD Prototyping Lab for his help in laser cutting. The authors also like to acknowledge Dr Preetham Suresh for use of the UCSD Simulation Training Center.