Reducing the risks of endoscopic sinonasal surgery in the Covid-19 era.

OBJECTIVES: Many routine sinonasal procedures utilising powered instruments are regarded as aerosol-generating. This study aimed to assess how different instrument settings affect detectable droplet spread and patterns of aerosolised droplet spread during simulated sinonasal surgery in order to identify mitigation strategies. DESIGN: Simulation series using three-dimensional (3-D) printed sinonasal model. Fluorescein droplet spread was assessed following microdebriding and drilling of fluorescein-soaked grapes and bones, respectively. SETTING: University dry lab. PARTICIPANTS: 3-D printed sinonasal model. MAIN OUTCOME MEASURES: Patterns of aerosolised droplet spread. RESULTS AND CONCLUSION: There were no observed fluorescein droplets or splatter in the measured surgical field after microdebridement of nasal polyps at aspecific irrigation rate and suction pressure. Activation of the microdebrider in the presence of excess fluid in the nasal cavity (reduced or blocked suction pressure, excessive irrigation fluid or bleeding) resulted in detectable droplet spread. Drilling with either coarse diamond or cutting burs resulted in detectable droplets and greater spread was observed when drilling within the anterior nasal cavity. High-speed drilling is a high-risk AGP but the addition of suction using a third hand technique reduces detectable droplet spread outside the nasal cavity. Using the instrument outside the nasal cavity inadvertently, or when unblocking, produces greater droplet spread and requires more caution.

Impact of COVID-19 Pandemic on Ambulatory and Operating Room Rhinology Practice in the US.

INTRODUCTION: The pandemic caused by the novel coronavirus virus has altered all facets of clinical practice in the United States. The goal of this study is to better understand the impact of COVID-19 on rhinologic ambulatory and operative practice. METHODS: A 27-item survey to assess these objectives was created and approved by the Division of Rhinology faculty at Rush University Medical Center in April 2020. The survey was then distributed to rhinologists in a web based format via www.surveymonkey.com from April 10 through April 23, 2020. RESULTS: A total of 277 U.S based rhinologists responded to the survey (23.04%). The most common practice types were single specialty private (44.9%) and academic (24.6%). 90.2% practice in a state under a shelter in place order. Comparing pre-COVID baseline to during-COVID, there was statistically significant reduction in the number of patients of seen daily in clinic (p < 0.001). The number of nasal endoscopies in the office and surgical procedures fell dramatically. Overall, 5 respondent rhinologists have been infected with COVID-19 and 27 have been furloughed. CONCLUSION: COVID-19 has drastically affected rhinologic practice. There is a dramatic reduction of in person care in the office setting and surgical management of sinonasal and skull base disease. Enhanced PPE is being used in only half of potentially aerosolizing procedures which represents an area of further education. Novel approaches such as use of virtual encounters and point of care testing should be considered as options to facilitate care.

Quantification of Aerosol Particle Concentrations During Endoscopic Sinonasal Surgery in the Operating Room.

BACKGROUND: Recent indirect evidence of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) transmission during endoscopic endonasal procedures has highlighted the dearth of knowledge surrounding aerosol generation with these procedures. As we adapt to function in the era of Coronavirus Disease 2019 (COVID-19) a better understanding of how surgical techniques generate potentially infectious aerosolized particles will enhance the safety of operating room (OR) staff and learners. OBJECTIVE: To provide greater understanding of possible SARS-CoV-2 exposure risk during endonasal surgeries by quantifying increases in airborne particle concentrations during endoscopic sinonasal surgery. METHODS: Aerosol concentrations were measured during live-patient endoscopic endonasal surgeries in ORs with an optical particle sizer. Measurements were taken throughout the procedure at six time points: 1) before patient entered the OR, 2) before pre-incision timeout during OR setup, 3) during cold instrumentation with suction, 4) during microdebrider use, 5) during drill use and, 6) at the end of the case prior to extubation. Measurements were taken at three different OR position: surgeon, circulating nurse, and anesthesia provider. RESULTS: Significant increases in airborne particle concentration were measured at the surgeon position with both the microdebrider (p = 0.001) and drill (p = 0.001), but not for cold instrumentation with suction (p = 0.340). Particle concentration did not significantly increase at the anesthesia position or the circulator position with any form of instrumentation. Overall, the surgeon position had a mean increase in particle concentration of 2445 particles/ft3 (95% CI 881 to 3955; p = 0.001) during drill use and 1825 particles/ft3 (95% CI 641 to 3009; p = 0.001) during microdebrider use. CONCLUSION: Drilling and microdebrider use during endonasal surgery in a standard operating room is associated with a significant increase in airborne particle concentrations. Fortunately, this increase in aerosol concentration is localized to the area of the operating surgeon, with no detectable increase in aerosol particles at other OR positions.

Suction mitigation of airborne particulate generated during sinonasal drilling and cautery.

BACKGROUND: Coronavirus disease 2019 (COVID-19) has significantly impacted endonasal surgery, and recent experimentation has demonstrated that sinonasal drilling and cautery have significant propensity for airborne particulate generation immediately adjacent to the surgical field. In the present investigation, we assessed nasopharyngeal suctioning as a mitigation strategy to decrease particulate spread during simulated endonasal surgical activity. METHODS: Airborne particulate generation in the 1-µm to 10-µm range was quantified with an optical particle sizer in real-time during cadaveric-simulated anterior and posterior endonasal drilling and cautery conditions. To test suction mitigation, experiments were performed both with and without a rigid suction placed in the contralateral nostril, terminating in the nasopharynx. RESULTS: Both anterior (medial maxillary wall and nasal septum) and posterior (sphenoid rostrum) drilling produced significant particulate generation in the 1-µm to 10-µm range throughout the duration of drilling (p < 0.001) without the use of suction, whereas nasopharyngeal suction use eliminated the detection of generated airborne particulate. A similar effect was seen with nasal cautery, with significant particle generation (p < 0.001) that was reduced to undetectable levels with the use of nasopharyngeal suction. CONCLUSION: The use of nasopharyngeal suctioning via the contralateral nostril minimizes airborne particulate spread during simulated sinonasal drilling and cautery. In the era of COVID-19, this technique offers an immediately available measure that may increase surgical safety.