Cadaveric Simulation of Endoscopic Endonasal Procedures: Analysis of Droplet Splatter Patterns During the COVID-19 Pandemic

Fluorescence guidance in skull base surgery: Applications and limitations - A systematic review

Introduction

Intraoperative fluorescence guidance is a well-established surgical adjunct in high-grade glioma surgery. In contrast, the clinical use of such dyes and technology has been scarcely reported in skull base surgery.

Research question

We aimed to systematically review the clinical applications of different fluorophores in both open and endonasal skull base surgery.

Material and methods

We performed a systematic review and discussed the current literature on fluorescence guidance in skull base surgery.

Results

After a comprehensive literature search, 77 articles on skull base fluorescence guidance were evaluated. A qualitative analysis of the articles is presented, discussing clinical indications and current controversies. The use of intrathecal fluorescein was the most frequently reported in the literature. Beyond that, 5-ALA and ICG were two other fluorescent dyes most extensively discussed, with some experimental fluorophore applications in skull base surgery.

Discussion and conclusion

Intraoperative fluorescence imaging can serve as an adjunct technology in skull base surgery. The scope of initial indications of these fluorophores has expanded beyond malignant glioma resection alone. We discuss current use and controversies and present an extensive overview of additional indications for fluorescence imaging in skull base pathologies. Further quantitative studies will be needed in the future, focusing on tissue selectivity and time-dependency of the different fluorophores currently commercially available, as well as the development of new compounds to expand applications and facilitate skull base surgeries.

Aerosol and Droplet Generation from Open Rhinoplasty: Surgical Risk in the Pandemic Era

Introduction: The coronavirus disease 2019 pandemic has led to concerns over transmission risk from head and neck operations including facial cosmetic surgeries. Objectives: To quantify droplet and aerosol generation from rhinoplasty techniques in a human anatomic specimen model using fluorescein staining and an optical particle sizer. Methods: Noses of human anatomic specimens were infiltrated using 0.1% fluorescein. Droplets and aerosols were measured during rhinoplasty techniques including opening the skin-soft tissue envelope, monopolar electrocautery, endonasal rasping, endonasal osteotomy, and percutaneous osteotomy. Results: No visible droplet contamination was observed for any rhinoplasty techniques investigated. Compared with the negative control of anterior rhinoscopy, total 0.300-10.000 μm aerosols were increased after monopolar electrocautery (p < 0.001) and endonasal rasp (p = 0.003). Opening the skin-soft tissue envelope, endonasal osteotomies, and percutaneous osteotomies did not generate a detectable increase in aerosols (p > 0.15). Discussion and Conclusions: In this investigation, droplets were not observed under ultraviolet light, and aerosol generation was noted only with cautery and endonasal rasping.

Adapting management strategies for sellar-suprasellar lesions during the COVID-19 pandemic: a pragmatic approach from the frontline

PURPOSE

During the ongoing COVID-19 pandemic, endonasal surgeries for sellar-suprasellar lesions were discouraged due to the risk of transmission of the disease. We reviewed the changes in our management protocol for these lesions as our disease understanding and preparedness evolved.

MATERIALS AND METHODS

This was a retrospective observational study including patients with sellar-suprasellar and clival lesions presenting to us between March and October 2020. Management protocols were divided into three phases based on the prevalence of the disease and the number of mandatory preoperative COVID-19 tests being conducted. The surgical approach used was analyzed in relation to the preferred approach during pre-COVID times, and surgical outcomes and complications were noted.

RESULTS

A total of 31 cases were operated during this period. During Phase I (low prevalence; no preoperative COVID testing) endonasal surgeries were largely abandoned in favor of transcranial approaches. In Phase II (medium prevalence; one preoperative COVID test) we gradually resumed endonasal surgeries for 'emergent' and 'essential' cases, and subsequently in Phase III (high prevalence; two preoperative COVID tests), we had no hesitation in performing 'elective' endonasal surgeries with additional barriers for prevention of aerosol transmission. No patient developed COVID-19 infection postoperatively. Eight HCWs in our department acquired the disease during this period, none of whom were directly involved in the surgeries for the above cohort of patients.

CONCLUSIONS

With a strict preoperative COVID testing protocol, adherence to proper drilling techniques and using additional barriers to prevent droplet and aerosol spread, endonasal surgeries for sellar-suprasellar lesions are safe during this COVID-19 pandemic.

Health Care Simulation as a Training Tool for Epidemic Management: A Systematic Review

SUMMARY STATEMENT

The objective of this research was to identify and review studies that have evaluated the impact of simulation-based training on health care professionals during epidemics.All studies in health care simulation-based training published during the last 5 epidemics with a global impact (SARS-CoV, H1N1, MERS, Ebola, SARS-CoV-2; through July 2021) were selected from a systematic search of PUBMED, EMBASE, and key journals.The search strategy identified 274 studies; 148 met the inclusion criteria and were included. Most of the studies were developed in response to SARS-CoV-2 infection (n = 117, 79.1%), used a descriptive approach (n = 54, 36.5%), and were used to train technical skills (n = 82, 55.4%).This review demonstrates a growing interest in publications related to health care simulation and epidemics. Most of the literature is marked by limited study designs and outcome measurements, although there is a trend toward the use of more refined methodologies in the most recent publications. Further research should seek the best evidence-based instructional strategies to design training programs in preparation for future outbreaks.

Instrumental in Surgery: A Narrative Review on Energy-based Surgical Cutting Devices and Surgical Smoke

OBJECTIVE

To provide an informed understanding of existing energy-based surgical cutting technologies and aerosol-generating surgical procedures. We provide a perspective on the future innovation and research potential in this space for the benefit of surgeons, physicians, engineers, and researchers alike.

BACKGROUND

Surgery is a treatment for many medical conditions, the success of which depends on surgical cutting instruments that enable surgeons to conduct surgical procedures for tissue cutting and manipulation. Energy-based surgical cutting tools improve accuracy and limit unnecessary destruction of healthy tissues and cells, but can generate surgical smoke and aerosols, which can be handled using surgical smoke evacuation technology.

METHODS

A narrative review was conducted to explore existing literature describing the history and development of energy-based surgical instruments, their mechanisms of action, aerosol-generating medical procedures, surgical smoke and aerosols from aerosol-generating medical procedures, and the recommended mitigation strategies, as well as research on rapid biological tissue analyzing devices to date.

CONCLUSIONS

Smoke evacuation technology may provide diagnostic information regarding tissue pathology, which could eliminate health concerns and revolutionize surgical accuracy. However, further research into surgical smoke is required to quantify the measurable risk to health it poses, the cutting conditions, under which it is generated and to develop advanced diagnostic approaches using this information.

International consensus statement on allergy and rhinology: Allergic rhinitis - 2023

BACKGROUND

In the 5 years that have passed since the publication of the 2018 International Consensus Statement on Allergy and Rhinology: Allergic Rhinitis (ICAR-Allergic Rhinitis 2018), the literature has expanded substantially. The ICAR-Allergic Rhinitis 2023 update presents 144 individual topics on allergic rhinitis (AR), expanded by over 40 topics from the 2018 document. Originally presented topics from 2018 have also been reviewed and updated. The executive summary highlights key evidence-based findings and recommendation from the full document.

METHODS

ICAR-Allergic Rhinitis 2023 employed established evidence-based review with recommendation (EBRR) methodology to individually evaluate each topic. Stepwise iterative peer review and consensus was performed for each topic. The final document was then collated and includes the results of this work.

RESULTS

ICAR-Allergic Rhinitis 2023 includes 10 major content areas and 144 individual topics related to AR. For a substantial proportion of topics included, an aggregate grade of evidence is presented, which is determined by collating the levels of evidence for each available study identified in the literature. For topics in which a diagnostic or therapeutic intervention is considered, a recommendation summary is presented, which considers the aggregate grade of evidence, benefit, harm, and cost.

CONCLUSION

The ICAR-Allergic Rhinitis 2023 update provides a comprehensive evaluation of AR and the currently available evidence. It is this evidence that contributes to our current knowledge base and recommendations for patient evaluation and treatment.

Surgical Management of Inferior Turbinate Hypertrophy in the Era of Widespread Communicable Disease

Inferior turbinate reduction procedures have been performed for decades. After significant evolution, turbinoplasty and other mucosal-sparing techniques have become the main method to successfully reduce turbinate hypertrophy. The debate of which technique produces the most effective and durable outcomes is ongoing. During this critical era of widespread communicable diseases, including but not limited to COVID-19, HIV, and hepatitis, additional attention is necessary to balance outcomes with a degree of generation of airborne particles when selecting a technique. This review article aims to identify the optimal method for inferior turbinate reduction that weighs both outcomes and aerosol production. The MEDLINE database was searched to discover relevant publications through August 2022. Key search terms included inferior turbinate hypertrophy, turbinate reduction surgery, turbinoplasty methods, surgical management of turbinate hypertrophy, surgical aerosol generation, COVID-19 surgery, surgery smoke plume, SARS-CoV-2 transmission during surgery, and nasal procedures COVID-19 aerosols. Surgical management of the inferior turbinates includes radiofrequency ablation (RFA), microdebrider-assisted turbinoplasty (MAIT), electrocautery, laser, and ultrasound. Piezo-assisted turbinoplasty and a turbinate-specific coblation wand are new additions to the literature. All techniques appear to improve patient symptoms of nasal obstruction. MAIT and RFA are comparable, although MAIT demonstrated better long-term outcomes in some studies and appears to generate fewer airborne particles. Studies evaluating the production of aerosols due to RFA are lacking. Ultrasound outcomes are also excellent and generate no aerosols, but the technique has not been compared against the microdebrider. Electrocautery can result in increased pain and crusting for patients and causes the highest amount of aerosols. Deficiencies of current studies, including a lack of comparison of aerosol generation, duration of follow-up, omission of outfracture, and inadequate randomized controlled trials among existing and new techniques, have limited the identification of the best inferior turbinate reduction method. Given the durability of MAIT and its minimal aerosol production, it can be reinforced as the most sensible technique until further evidence is available.

In-office Eustachian tube balloon dilation under local anesthesia as a response to operating room restrictions associated with the COVID-19 pandemic

Objective

To evaluate the feasibility of local anesthesia for Eustachian tube balloon dilation as an in-office procedure for the treatment of Eustachian tube dilatory dysfunction as a response to the restriction measures of the coronavirus disease 2019 pandemic.

Method

Patients with Eustachian tube dilatory dysfunction refractory to nasal steroids undergoing Eustachian tube balloon dilation in local anesthesia were enrolled in a prospective observational cohort between May 2020 and April 2022. The patients were assessed by using the Eustachian tube dysfunction questionnaire (ETDQ-7) score and Eustachian tube mucosal inflammation scale. They underwent clinical examination, tympanometry, and pure tone audiometry. Eustachian tube balloon dilation was performed in-office under local anesthesia. The perioperative experience of the patients was recorded using a 1-10 visual analog scale (VAS).

Results

Thirty patients (47 Eustachian tubes) underwent the operation successfully. One attempted dilation was aborded because the patient displayed anxiety. Local anesthesia was performed by using topical lidocaine and nasal packing for all patients. Three patients required an infiltration of the nasal septum and/or tubal nasopharyngeal orifice. The mean time of the operation was 5.7 min per Eustachian tube dilation. The mean level of discomfort during the intervention was 4.7 (on a 1-10 VAS scale). All patients returned home immediately after the intervention. The only reported complication was a self-limiting subcutaneous emphysema.

Conclusion

Eustachian tube balloon dilation can be performed under local anesthesia and is well tolerated by most patients. In the patients reported in this study, no major complications occurred. In order to free operation room capacities, the intervention can be performed in an in-office setting with satisfactory patient feedback.

Exploring health service preparation for the COVID-19 crisis utilizing simulation-based activities in a Norwegian hospital: a qualitative case study

Introduction

The first wave of the COVID-19 pandemic caused stress in healthcare organizations worldwide. Hospitals and healthcare institutions had to reorganize their services to meet the demands of the crisis. In this case study, we focus on the role of simulation as part of the pandemic preparations in a large hospital in Norway. The aim of this study is to explore hospital leaders' and simulation facilitators' expectations of, and experiences of utilizing simulation-based activities in the preparations for the COVID-19 pandemic.

Methods

This is a qualitative case study utilizing semi-structured in-depth interviews with hospital leaders and simulation facilitators in one large hospital in Norway. The data were sorted under three predefined research topics and further analyzed by inductive, thematic analysis according to Braun and Clarke within these pre-defined topics.

Results

Eleven members of the hospital leadership and simulation facilitators were included in the study. We identified four themes explaining why COVID-19 related simulation-based activities were initiated, and perceived consequences of the activities; 1) a multifaceted method like simulation fitted a multifaceted crisis, 2) a well-established culture for simulation in the hospital was crucial for scaling up simulation-based activities during the crisis, 3) potential risks were outweighed by the advantages of utilizing simulation-based activities, and finally 4) hospital leaders and simulation facilitators retrospectively assessed the use of simulation-based activities as appropriate to prepare for a pandemic crisis.

Conclusions

The hospital leadership’s decision to utilize simulation-based activities in preparing for the COVID-19 crisis may be explained by many factors. First, it seems that many years of experience with systematic use of simulation-based activities within the hospital can explain the trust in simulation as a valuable tool that were easy to reach. Second, both hospital leaders and simulation facilitators saw simulation as a unique tool for the optimization of the COVID-19 response due to the wide applicability of the method. According to hospital leaders and simulation facilitators, simulation-based activities revealed critical gaps in training and competence levels, treatment protocols, patient logistics, and environmental shortcomings that were acted upon, suggesting that institutional learning took place.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12913-022-07826-5.

A negative-pressure face-mounted system reduces aerosol spread during endonasal endoscopic surgery

Purpose: As there is a potential risk of Covid-19 transmission during endonasal surgery we studied methods to reduce droplet and aerosol generation during these procedures. Methods: Droplet spread was assessed using ultraviolet light and a camera that detected fluorescence in the operative field and surgeon’s personal protective equipment. Density of aerosols sized <10µ was measured using a photometric particle counter. We designed a face-mounted negative-pressure mask placed on the patients face during endoscopic endonasal surgery. Sixteen patients were recruited between October 2020 to March 2021 and randomly assigned to the mask and no-mask groups. We compared droplet spread and aerosols generated in both groups, with copious irrigation and continuous suction during drilling forming the mainstay of surgical technique in all cases. Results: Droplet contamination due to direct spillage of fluorescein from the syringe was noted in two patients. Aerosol density rose during sphenoid drilling in both groups, with no significant difference when continuous suction and irrigation were employed (1.27 times vs. 1.07 times the baseline, p=0.248). Aerosol density rose significantly when suction and irrigation were interrupted in the no-mask group (44.9 times vs. 1.2 times, p=0.028), which was not seen when the mask was used. Conclusions: Aerosol generation increases during drilling in endonasal procedures and is a concern during this pandemic. The use of a rigid suction close to the drill along with copious irrigation is effective in reducing aerosol spread. The use of a negative pressure mask provides additional safety when inadvertent blockage of suction and inadequate irrigation occur.

Safety for the Rhinologist in the Age of COVID-19: Mask Use, Nasal Corticosteroids, Saline Irrigation, and Endoscopic Procedures – Literature Review

Introduction  Coronavirus disease 2019 (COVID-19) has claimed millions of lives. Adequate protection of the professionals involved in patient care is essential in the battle against this disease. However, there is much uncertainty involving safety-relarted topics that are of particular interest to the rhinologist in the context of COVID-19.

Objective  To evaluate the current evidence regarding three safety-related topics: mask and respirator use, performance of nasal endoscopic procedures, and use of topical nasal and intranasal medications (saline irrigation and nasal corticosteroids).

Methods  A literature review was performed on the PubMed, Scopus, and Cochrane databases, with standardized search queries for each of the three topics of interest.

Results  In total, 13 articles on mask use, 6 articles on the safety of nasal corticosteroids, 6 articles on the safety of nasal endoscopic procedures, and 1 article on nasal irrigation with saline solution were included in the final analysis.

Conclusion  N95 respirators are essential for the adequate protection of otolaryngologists. If reuse is necessary, physical methods of sterilization must be employed. No evidence was found to contraindicate the use of nasal corticosteroids, whether acute (in the management of sinonasal inflammatory conditions) or continued (in patients who use them chronically). Nasal irrigation with saline solution apparently does not increase the risk in the context of COVID-19. Nasal endoscopic procedures should only be performed after testing the patient for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and the surgical team must wear full personal protective equipment to prevent aerosol exposure.

Objective Assessment of Aerosolization During Transnasal Endoscopy: A Systematic Review

OBJECTIVE

The goal of this systematic review is to assimilate the literature on objective assessment of particulate aerosolization during transnasal endoscopic procedures.

DATA SOURCES

PubMed and hand-searched articles.

REVIEW METHODS

The PubMed electronic database was searched using Medical Subject Headings and free-text search terms relating to aerosolization and transnasal endoscopic procedures from inception to November 16, 2020. References were hand-searched to identify additional publications for consideration. Inclusion in the systematic review required quantification of aerosol generation during clinic transnasal endoscopic procedures. Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and flowchart were followed during the systematic review.

RESULTS

Eight of 900 studies met criteria for inclusion in the systematic review. Five studies tested nasal endoscopy with mixed findings on the risk of aerosol generation during this procedure. Two studies assessed flexible fiberoptic laryngoscopy and also reported mixed findings. Breathing, sneezing, speech, and spray anesthetic/decongestants were found to consistently increase aerosol generation above baseline. A number of studies tested new and general mitigation strategies and were found to be effective in decreasing aerosol generation.

CONCLUSIONS

The coronavirus disease 2019 pandemic has informed many considerations regarding patient and provider safety. It is valuable to understand the risk during outpatient otolaryngology procedures through the quantification of aerosolization. There are several effective methods to control aerosolization during these procedures. The findings of this systematic review will inform appropriate precautions to protect against spread of infectious agents by aerosolization.

Are medical procedures that induce coughing or involve respiratory suctioning associated with increased generation of aerosols and risk of SARS-CoV-2 infection? A rapid systematic review

BACKGROUND

The risk of transmission of SARS-CoV-2 from aerosols generated by medical procedures is a cause for concern.

AIM

To evaluate the evidence for aerosol production and transmission of respiratory infection associated with procedures that involve airway suctioning or induce coughing/sneezing.

METHODS

The review was informed by PRISMA guidelines. Searches were conducted in PubMed for studies published between January 1st, 2003 and October 6th, 2020. Included studies examined whether nasogastric tube insertion, lung function tests, nasendoscopy, dysphagia assessment, or suctioning for airway clearance result in aerosol generation or transmission of SARS-CoV-2, SARS-CoV, MERS, or influenza. Risk of bias assessment focused on robustness of measurement, control for confounding, and applicability to clinical practice.

FINDINGS

Eighteen primary studies and two systematic reviews were included. Three epidemiological studies found no association between nasogastric tube insertion and acquisition of respiratory infections. One simulation study found low/very low production of aerosols associated with pulmonary lung function tests. Seven simulation studies of endoscopic sinus surgery suggested significant increases in aerosols but findings were inconsistent; two clinical studies found airborne particles associated with the use of microdebriders/drills. Some simulation studies did not use robust measures to detect particles and are difficult to equate to clinical conditions.

CONCLUSION

There was an absence of evidence to suggest that the procedures included in the review were associated with an increased risk of transmission of respiratory infection. In order to better target precautions to mitigate risk, more research is required to determine the characteristics of medical procedures and patients that increase the risk of transmission of SARS-CoV-2.

Aerosolization risk during endoscopic transnasal surgery: a prospective qualitative and quantitative microscopic analysis of particles spreading in the operating room

OBJECTIVE

The coronavirus disease 2019 (COVID-19) pandemic represents the greatest public health emergency of this century. The primary mode of viral transmission is droplet transmission through direct contact with large droplets generated during breathing, talking, coughing, and sneezing. However, the virus can also demonstrate airborne transmission through smaller droplets (< 5 μm in diameter) generated during various medical procedures, collectively termed aerosol-generating procedures. The aim of this study was to analyze droplet contamination of healthcare workers and splatter patterns in the operating theater that resulted from endoscopic transnasal procedures in noninfected patients.

METHODS

A prospective nonrandomized microscopic evaluation of contaminants generated during 10 endoscopic transnasal procedures performed from May 14 to June 11, 2020, in the same operating theater was carried out. A dilution of monosodium fluorescein, repeatedly instilled through nasal irrigation, was used as a marker of contaminants generated during surgical procedures. Contaminants were collected on detectors worn by healthcare workers and placed in standard points in the operating theater. Analysis of number, dimensions, and characteristics of contaminants was carried out with fluorescence microscopy.

RESULTS

A total of 70 samples collected from 10 surgical procedures were analyzed. Liquid droplets and solid-tissue fragments were identified as contaminants on all detectors analyzed. All healthcare workers appeared to have been exposed to a significant number of contaminants. A significant degree of contamination was observed in every site of the operating room. The mean (range) diameter of liquid droplets was 4.1 (1.0-26.6) μm and that of solid fragments was 23.6 (3.5-263.3) μm.

CONCLUSIONS

Endoscopic endonasal surgery is associated with the generation of large amounts of contaminants, some of which measure less than 5 μm. All healthcare workers in the surgical room are exposed to a significant and similar risk of contamination; therefore, adequate personal protective equipment should be employed when performing endoscopic endonasal surgical procedures.

One year into the COVID-19 pandemic: What do we know so far from studies assessing risk and mitigation of droplet aerosolisation during endonasal surgery? A systematic review

Objectives

As we pass the anniversary of the declaration of a global pandemic by the World Health Organisation, it invites us to reflect upon the inescapable changes that coronavirus has wrought upon ENT and, in particular, rhinological practice. As it remains unclear when we will emerge from the shadow of COVID‐19, a critical analysis of the evidence base on both the assessment and mitigation of risk is vital for ENT departments worldwide. This article presents a systematic review of the literature examining articles which consider either the quantification of risk or strategies to mitigate risk specifically in the setting of rhinological surgery.

Design

Systematic literature review.

Results

The literature search yielded a total of 3406 returns with 24 articles meeting eligibility criteria. A narrative synthesis stratified results into two broad themes: (1) those which made an assessment as to the aerosolisation of droplets during sinus surgery, further sub‐divided into work which considered macroscopically visible droplets and that which considered smaller particles; (2) and those studies which examined the mitigation of this risk.

Conclusion

Studies considering the aerosolisation of both droplets and smaller particles suggest endonasal surgery carries significant risk. While results both highlight a range of innovative adjunctive strategies and support suction as an important intervention to reduce aerosolisation, appropriate use of personal protective equipment (PPE) should be considered mandatory for all healthcare professionals involved in rhinological surgery. Studies have demonstrated that close adherence to PPE use is effective in preventing COVID‐19 infection.

Body Donation, Teaching, and Research in Dissection Rooms in Spain in Times of Covid-19

The state of alarm due to Covid-19 pandemic in Spain stopped all educational and most university research activities. The Spanish Anatomical Society (SAE) Consensus Expert Group on Body Donations piloted a study based on a questionnaire to know the status of body donations and dissection activities during the lockdown, as well as the future implications of Covid-19 pandemic for body donation programs and anatomy teaching. The questionnaire results show that Spanish Universities refused body donations and stopped all dissection research and teaching. The Covid-19 expected influence on anatomy teaching was referred to the increase in teaching workforce and resources required to apply the new safety measures to future practical activities, as well as to prepare and adapt teaching material for online-only programs. The application of reinforced safety measures was expected to be perceived by the respondent's students as a gain in teaching quality, while the transformation of the anatomy courses in online-only programs will be perceived as a quality decrease. The respondent's concerns about future institutional implications of the pandemic were related to increased costs of the adaptation of the facilities and the reinforced preventive measures, as well as the eventual decrease in donations. The complete lockdown applied to dissection rooms was not justified by scientific evidence and represented a break of the confidence deposed in the institutions by the donors. A consensus is required for the adoption of a renewed, comprehensive protocol for present and future body donations including the evidence Covid-19 pandemic has contributed to create.

Nasal endoscopy, room filtration, and aerosol concentrations during live outpatient encounters: a prospective, case-control study

Background

The coronavirus disease 2019 (COVID‐19) pandemic has highlighted safety concerns surrounding possible aerosol‐generating procedures, but comparative data on the smallest particles capable of transmitting this virus remain limited. We evaluated the effect of nasal endoscopy on aerosol concentration and the role of a high‐efficiency particulate air (HEPA) filter in reducing aerosol concentration.

Methods

Otolaryngology patients were prospectively enrolled in an outpatient, cross‐sectional study. Demographic information and clinic room characteristics were recorded. A scanning mobility particle sizer and GRIMM aerosol monitor measured aerosols 14.3 nm to 34 μm in diameter (i.e., particles smaller than those currently examined in the literature) during (1) nasal endoscopy (± debridement) and (2) no nasal endoscopy encounters. One‐way analysis of variance (ANOVA) and Student's t test were performed to compare aerosol concentrations and impact of HEPA filtration.

Results

Sixty‐two patients met inclusion criteria (25 nasal endoscopy without debridement; 18 nasal endoscopy with debridement; 19 no nasal endoscopy). There was no significant difference in age or gender across cohorts. Aerosol concentration in the nasal endoscopy cohort (± debridement) was not greater than the no nasal endoscopy cohort (p = 0.36; confidence interval [95% CI], −1.76 to 0.17 μg/m³; and p = 0.12; 95% CI, −0.11 to 2.14 μg/m³, respectively). Aerosol concentrations returned to baseline after 8.76 min without a HEPA filter versus 4.75 min with a HEPA filter (p = 0.001; 95% CI, 1.73–6.3 min).

Conclusion

Using advanced instrumentation and a comparative study design, aerosol concentration was shown to be no greater during nasal endoscopy versus no endoscopy encounters. HEPA filter utilization reduced aerosol concentrations significantly faster than no HEPA filter.

Aerosolisation in endonasal endoscopic pituitary surgery

PURPOSE

To determine the particle size, concentration, airborne duration and spread during endoscopic endonasal pituitary surgery in actual patients in a theatre setting.

METHODS

This observational study recruited a convenience sample of three patients. Procedures were performed in a positive pressure operating room. Particle image velocimetry and spectrometry with air sampling were used for aerosol detection.

RESULTS

Intubation and extubation generated small particles (< 5 µm) in mean concentrations 12 times greater than background noise (p < 0.001). The mean particle concentrations during endonasal access were 4.5 times greater than background (p = 0.01). Particles were typically large (> 75 µm), remained airborne for up to 10 s and travelled up to 1.1 m. Use of a microdebrider generated mean aerosol concentrations 18 times above baseline (p = 0.005). High-speed drilling did not produce aerosols greater than baseline. Pituitary tumour resection generated mean aerosol concentrations less than background (p = 0.18). Surgical drape removal generated small and large particles in mean concentrations 6.4 times greater than background (p < 0.001).

CONCLUSION

Intubation and extubation generate large amounts of small particles that remain suspended in air for long durations and disperse through theatre. Endonasal access and pituitary tumour resection generate smaller concentrations of larger particles which are airborne for shorter periods and travel shorter distances.

Diagnosis of Anosmia and Hyposmia: A Systematic Review

Background

Anosmia and hyposmia have many etiologies, including trauma, chronic sinusitis, neoplasms, and respiratory viral infections such as rhinovirus and SARS-CoV-2. We aimed to systematically review the literature on the diagnostic evaluation of anosmia/hyposmia.

Methods

PubMed, EMBASE, and Cochrane databases were searched for articles published since January 1990 using terms combined with Medical Subject Headings (MeSH). We included articles evaluating diagnostic modalities for anosmia, written in the English language, used original data, and had two or more patients.

Results

A total of 2065 unique titles were returned upon the initial search. Of these, 226 abstracts were examined, yielding 27 full-text articles meeting inclusion criteria (Level of evidence ranging from 1 to 4; most level 2). The studies included a total of 13,577 patients. The most utilized diagnostic tools were orthonasal smell tests (such as the Sniffin’ Sticks and the UPSIT, along with validated abridged smell tests). Though various imaging modalities (including MRI and CT) were frequently mentioned in the workup of olfactory dysfunction, routine imaging was not used to primarily diagnose smell loss.

Conclusion

The literature includes several studies on validity and reliability for various smell tests in diagnosing anosmia. Along with a thorough history and physical, validated orthonasal smell tests should be part of the workup of the patient with suspected olfactory dysfunction. The most widely studied modality was MRI, but criteria for the timing and sequence of imaging modalities was heterogenous.

Aerosol and droplet generation from orbital repair: Surgical risk in the pandemic era

INTRODUCTION

The highly contagious COVID-19 has resulted in millions of deaths worldwide. Physicians performing orbital procedures may be at increased risk of occupational exposure to the virus due to exposure to secretions. The goal of this study is to measure the droplet and aerosol production during repair of the inferior orbital rim and trial a smoke-evacuating electrocautery handpiece as a mitigation device.

MATERIAL AND METHODS

The inferior rim of 6 cadaveric orbits was approached transconjunctivally using either standard or smoke-evacuator electrocautery and plated using a high-speed drill. Following fluorescein inoculation, droplet generation was measured by counting under ultraviolet-A (UV-A) light against a blue background. Aerosol generation from 0.300-10.000 μm was measured using an optical particle sizer. Droplet and aerosol generation was compared against retraction of the orbital soft tissue as a negative control.

RESULTS

No droplets were observed following the orbital approach using electrocautery. Visible droplets were observed after plating with a high-speed drill for 3 of 6 orbits. Total aerosol generation was significantly higher than negative control following the use of standard electrocautery. Use of smoke-evacuator electrocautery was associated with significantly lower aerosol generation in 2 of 3 size groups and in total. There was no significant increase in total aerosols associated with high-speed drilling.

DISCUSSION AND CONCLUSIONS

Droplet generation for orbital repair was present only following plating with high-speed drill. Aerosol generation during standard electrocautery was significantly reduced using a smoke-evacuating electrocautery handpiece. Aerosols were not significantly increased by high-speed drilling.

COVID-19 Testing in the Era of Modern Neurosurgery: Mitigating Risk in Our Vulnerable Patient Populations

Background

The respiratory illness identified as coronavirus disease 2019 (COVID-19) has resulted in a pandemic illness that has changed the face of healthcare. As the COVID-19 pandemic continues, patients have continued to require neurosurgical interventions, and the endoscopic endonasal approach for surgery has continued to be a mainstay treatment of pituitary tumors and anterior skull base lesions.

Methods

We sought to highlight the current lack of recommendations regarding testing protocols for neurosurgical patients.

Results

We implemented a novel testing protocol for our patient populations at increased risk and have proposed a model that can be used at other institutions to mitigate the risk of complications associated with some forms of COVID-19 testing.

Conclusion

Patients with anterior skull base defects may be at risk with current COVID-19 testing protocols, and may benefit from alternative specimen collection strategies.

Aerosol and Droplet Risk of Common Otolaryngology Clinic Procedures

OBJECTIVES

Define aerosol and droplet risks associated with routine otolaryngology clinic procedures during the COVID-19 era.

METHODS

Clinical procedures were simulated in cadaveric heads whose oral and nasal cavities were coated with fluorescent tracer (vitamin B2) and breathing was manually simulated through retrograde intubation. A cascade impactor placed adjacent to the nares collected generated particles with aerodynamic diameters ≤14.1 µm. The 3D printed models and syringes were used to simulate middle and external ear suctioning as well as open suctioning, respectively. Provider's personal protective equipment (PPE) and procedural field contamination were also recorded for all trials using vitamin B2 fluorescent tracer.

RESULTS

The positive controls of nebulized vitamin B2 produced aerosol particles ≤3.30 µm and endonasal drilling of a 3D model generated particles ≤14.1 µm. As compared with positive controls, aerosols and small droplets with aerodynamic diameter ≤14.1 µm were not detected during rigid nasal endoscopy, flexible fiberoptic laryngoscopy, and rigid nasal suction of cadavers with simulated breathing. There was minimal to no field contamination in all 3 scenarios. Middle and external ear suctioning and open container suctioning did not result in any detectable droplet contamination. The clinic suction unit contained all fluorescent material without surrounding environmental contamination.

CONCLUSION

While patients' coughing and sneezing may create a baseline risk for providers, this study demonstrates that nasal endoscopy, flexible laryngoscopy, and suctioning inherently do not pose an additional risk in terms of aerosol and small droplet generation. An overarching generalization cannot be made about endoscopy or suctioning being an aerosol generating procedure.

LEVEL OF EVIDENCE

3.

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.

Novel Use of Vitamin B2 as a Fluorescent Tracer in Aerosol and Droplet Contamination Models in Otolaryngology

OBJECTIVE

During the COVID-19 era, a reliable method for tracing aerosols and droplets generated during otolaryngology procedures is needed to accurately assess contamination risk and to develop mitigation measures. Prior studies have not investigated the reliability of different fluorescent tracers for the purpose of studying aerosols and small droplets. Objectives include (1) comparing vitamin B2, fluorescein, and a commercial fluorescent green dye in terms of particle dispersion pattern, suspension into aerosols and small droplets, and fluorescence in aerosolized form and (2) determining the utility of vitamin B2 as a fluorescent tracer coating the aerodigestive tract mucosa in otolaryngology contamination models.

METHODS

Vitamin B2, fluorescein, and a commercial fluorescent dye were aerosolized using a nebulizer and passed through the nasal cavity from the trachea in a retrograde-intubated cadaveric head. In another scenario, vitamin B2 was irrigated to coat the nasal cavity and nasopharyngeal mucosa of a cadaveric head for assessment of aerosol and droplet generation from endonasal drilling. A cascade impactor was used to collect aerosols and small droplets ≤14.1 µm based on average aerodynamic diameter, and the collection chambers were visualized under UV light.

RESULTS

When vitamin B2 was nebulized, aerosols ≤5.4 µm were generated and the collected particles were fluorescent. When fluorescein and the commercial water tracer dye were nebulized, aerosols ≤8.61 µm and ≤2.08 µm respectively were generated, but the collected aerosols did not appear visibly fluorescent. Endonasal drilling in the nasopharynx coated with vitamin B2 irrigation yielded aerosols ≤3.30 µm that were fluorescent under UV light.

CONCLUSION

Vitamin B2's reliability as a fluorescent tracer when suspended in aerosols and small droplets ≤14.1 µm and known mucosal safety profile make it an ideal compound compared to fluorescein and commercial water-based fluorescent dyes for use as a safe fluorescent tracer in healthcare contamination models especially with human subjects.

Aerosol generation during cadaveric simulation of otologic surgery and live cochlear implantation

OBJECTIVE

The risk of SARS-CoV-2 transmission to healthcare workers through airborne aerosolization during otologic surgery has not been characterized. The objective of this study was to describe and quantify the aerosol generation during common otologic procedures in both cadaveric surgical simulation and live patient surgery.

METHODS

The number concentrations of generated aerosols in the particle size range of 0.30 to 10.0 μm were quantified using an optical particle sizer during both a cadaveric simulation of routine otologic procedures as well as cochlear implant surgery on live patients in the operating room.

RESULTS

In the cadaveric simulation, temporalis fascia graft harvest using cold techniques (without electrocautery) (n = 4) did not generate aerosols above baseline concentrations. Tympanoplasty (n = 3) and mastoidectomy (n = 3) both produced statistically significant increases in concentrations of aerosols (P < 0.05), predominantly submicron particles (< 1.0 μm). High-speed, powered drilling of the temporal bone during mastoidectomy with a Multi Flute cutting burr resulted in higher peak concentrations and greater number of spikes in aerosols than with a diamond burr. In the operating room, spikes in aerosols occurred during both cochlear implant surgeries.

CONCLUSION

In the cadaveric simulation, temporalis fascia graft harvest without electrocautery did not generate aerosol levels above baseline, while significant aerosol levels were generated during mastoidectomy and to a much less degree during tympanoplasty. Aerosol spikes were appreciated during cochlear implantation surgery in live patients.

LEVEL OF EVIDENCE

2.

Aerosol generation during routine rhinologic surgeries and in-office procedures

OBJECTIVE

Cadaveric simulations have shown endonasal drilling and cautery generate aerosols, which is a significant concern for otolaryngologists during the COVID-19 era. This study quantifies aerosol generation during routine rhinologic surgeries and in-office procedures in live patients.

METHODS

Aerosols ranging from 0.30 to 10.0 μm were measured in real-time using an optical particle sizer during surgeries and in-office procedures. Various mask conditions were tested during rigid nasal endoscopy (RNE) and postoperative debridement (POD).

RESULTS

Higher aerosol concentrations (AC) ranging from 2.69 to 10.0 μm were measured during RNE (n = 9) with no mask vs two mask conditions (P = .002 and P = .017). Mean AC (0.30-10.0 μm) were significantly higher during POD (n = 9) for no mask vs a mask covering the patient's mouth condition (mean difference = 0.16 ± 0.03 particles/cm3, 95% CI 0.10-0.22, P < .001). There were no discernible spikes in aerosol levels during endoscopic septoplasty (n = 3). Aerosol spikes were measured in two of three functional endoscopic sinus surgeries (FESS) with microdebrider. Using suction mitigation, there were no discernible spikes during powered drilling in two anterior skull base surgeries (ASBS).

CONCLUSION

Use of a surgical mask over the patient's mouth during in-office procedures or a mask with a slit for an endoscope during RNE significantly diminished aerosol generation. However, whether this reduction in aerosol generation is sufficient to prevent transmission of communicable diseases via aerosols was beyond the scope of this study. There were several spikes in aerosols during FESS and ASBS, though none were associated with endonasal drilling with the use of suction mitigation.

LEVEL OF EVIDENCE

4.

Aerosol and droplet generation from mandible and midface fixation: Surgical risk in the pandemic era

PURPOSE

The COVID-19 pandemic has led to concerns over transmission risk from healthcare procedures, especially when operating in the head and neck such as during surgical repair of facial fractures. This study aims to quantify aerosol and droplet generation from mandibular and midface open fixation and measure mitigation of airborne particles by a smoke evacuating electrocautery hand piece.

MATERIALS AND METHODS

The soft tissue of the bilateral mandible and midface of two fresh frozen cadaveric specimens was infiltrated using a 0.1% fluorescein solution. Surgical fixation via oral vestibular approach was performed on each of these sites. Droplet splatter on the surgeon's chest, facemask, and up to 198.12 cm (6.5 ft) away from each surgical site was measured against a blue background under ultraviolet-A (UV-A) light. Aerosol generation was measured using an optical particle sizer.

RESULTS

No visible droplet contamination was observed for any trials of mandible or midface fixation. Total aerosolized particle counts from 0.300-10.000 μm were increased compared to baseline following each use of standard electrocautery (n = 4, p < 0.001) but not with use of a suction evacuating electrocautery hand piece (n = 4, p = 0.103). Total particle counts were also increased during use of the powered drill (n = 8, p < 0.001).

CONCLUSIONS

Risk from visible droplets during mandible and midface fixation is low. However, significant increases in aerosolized particles were measured after electrocautery use and during powered drilling. Aerosol dispersion is significantly decreased with the use of a smoke evacuating electrocautery hand piece.

Prevalence and cross states comparison of case fatality rate and recovery rate of COVID 19/SARS-COV-2 in India

BACKGROUND AND AIM

CFR and RR are important indicator of disease pandemic. As of now no data is available about cross-states analysis of these. We aimed to evaluate CFR and RR of COVID-19 across majorly affected States in India.

METHOD

We observed and compared data of confirmed COVID-19 cases, number of deaths, number of recovered/discharged cases and calculated CFR and RR across majorly affected States/UT in India from official database of Government of India, State Government official bulletin, accurate database worldometer.

RESULTS

The data showed that Gujarat, Madhya Pradesh, West Bengal reported highest CFR on 8th April, 22nd April, 6th May, 1st June 2020 (95% CI 4.91 - 6.99). Kerala showed encouraging recovery rates 24.32%, 70.31%, 93.24%, 45.81% on 8th and 22nd April, 6th May and 1st June 2020 respectively. India had an average estimated weekly Recovery rate of newly discharged/recovered cases was 32.68% from 19th March to 1st June 2020. (95% CI 20- 45.4%). (The Recovery rate across India was 80.83% as on 22nd September 2020.).

CONCLUSION

The CFR of a disease varies greatly in different regions of the same Country and is influenced by numerous factors such as health control policies, medical standards, and detection efficiency and protocols apart from number of screening tests done. This comparison discusses need of evaluating policies with optimal reporting of medical history of affected persons when comparing COVID-19 case and fatality rates in different regions of the Country.

Diagnostic and therapeutic endonasal rhinologic procedures generating aerosol during COVID-19 pandemic: a systematized review

Introduction

Most rhinologic procedures, particularly endoscopic sinonasal procedures, are liable to produce aerosols. The severe acute respiratory syndrome coronavirus 2 (SARS-Co V-2) transmits via respiratory droplets, but the degree of its spread through airborne routes by aerosol is unclear.

Objective

The aim of this article is to counsel rhinologists on how to modify their conventional practice during the COVID-19 pandemic by prioritising the need of procedures, identifying aerosol- generating procedures and using precise personal protection equipment for various endonasal procedures.

Methods

We did a review of articles indexed for MEDLINE on PubMed, ENT Cochrane, DOAJ and Web of Science databases using the keywords nasal endoscopy, SARS‐CoV‐2, COVID‐19, aerosol generating medical procedures and rhinology to formulate guidelines for the safety of healthcare workers.

Results

The review included evidence from 28 articles from the otorhinolaryngology, surgery, infectious disease, head and neck surgery and cancer biology literature. We have provided recommendations and relevant information for rhinologists during the COVID-19 pandemic, based on the available studies and data, to warrant high-quality patient care and requisite levels of infection prevention during rhinology procedures.

Conclusion

In rhinology, marked care is advised during nasal packing, electrocauterisation and use of high-speed rotating devices in potentially infected tissue as they are considerable aerosol- producing procedures. The choice of personal protective equipment is based on the risk of exposure and possible modes of aerosol generation.

CSO (Canadian Society of Otolaryngology - Head & Neck Surgery) position paper on rhinologic and skull base surgery during the COVID-19 pandemic

Healthcare services in many countries have been partially or completely disrupted by the Coronavirus (COVID-19) pandemic since its onset in the end of 2019. Amongst the most impacted are the elective medical and surgical services in order to conserve resources to care for COVID-19 patients. As the number of infected patients decrease across Canada, elective surgeries are being restarted in a staged manner. Since Otolaryngologists - Head & Neck Surgeons manage surgical diseases of the upper aerodigestive tract where the highest viral load reside, it is imperative that these surgeries resume in a safe manner. The aim of this document is to compile the current best evidence available and provide expert consensus on the safe restart of rhinologic and skull base surgeries while discussing the pre-operative, intra-operative, and post-operative care and tips. Risk assessment, patient selection, case triage, and pre-operative COVID-19 testing will be analyzed and discussed. These guidelines will also consider the optimal use of personal protective equipment for specific cases, general and specific operative room precautions, and practical tips of intra-operative maneuvers to optimize patient and provider safety. Given that the literature surrounding COVID-19 is rapidly evolving, these recommendations will serve to start our specialty back into elective rhinologic surgeries over the next months and they may change as we learn more about this disease.

Coronavirus Disease-19 and Rhinology/Facial Plastics

This review summarizes the challenges and adaptations that have taken place in rhinology and facial plastics in response to the ongoing coronavirus disease-19 pandemic. In particular, the prolonged exposure and manipulation of the nasal and oral cavities portend a high risk of viral transmission. We discuss evidence-based recommendations to mitigate the risk of viral transmission through novel techniques and device implementation as well as increasing conservative management of certain pathologies.

A novel aerosolisation mitigation device for endoscopic sinus and skull base surgery in the COVID-19 era

Purpose

To provide a novel solution to reduce aerosol exposure in the operating room during endoscopic sinus and skull base procedures in the COVID-19 era.

Methods

We have designed a 3D printable midfacial mask that partially seals the nose, while allowing instrumentation during endoscopic transnasal surgery. The mask when connected to a vacuum system creates a constant negative pressure inside it, sucking out aerosols and gases generated during surgical procedures. Its effectiveness was tested using vapour exhalations by a human volunteer and drilling bone in a head model. The physical barrier effect was measured using fluorescein atomization in a head model.

Results

The pressure and airflow measured remained negative inside it in all the different situations tested. The mask was capable of completely evacuating human adult exhalation, and was more effective than the hand suction instrument. However, it was as effective as hand suction instrument at preventing aerosol spread from bone drilling. The physical barrier effect achieved a 72% reduction in the splatter created from the fluorescein atomization.

Conclusions

The mask effectively prevented the spread of aerosols and reduced droplet spread during simulated transnasal endoscopic skull base surgery in laboratory conditions. This device has potential benefits in protecting surgical personnel against airborne transmission of COVID-19 and could be useful in reducing chronic exposure to the hazard of surgical smoke.

Electronic supplementary material

The online version of this article (10.1007/s00405-020-06462-1) contains supplementary material, which is available to authorized users.

Aerosolisation during tracheal intubation and extubation in an operating theatre setting

Aerosol‐generating procedures such as tracheal intubation and extubation pose a potential risk to healthcare workers because of the possibility of airborne transmission of infection. Detailed characterisation of aerosol quantities, particle size and generating activities has been undertaken in a number of simulations but not in actual clinical practice. The aim of this study was to determine whether the processes of facemask ventilation, tracheal intubation and extubation generate aerosols in clinical practice, and to characterise any aerosols produced. In this observational study, patients scheduled to undergo elective endonasal pituitary surgery without symptoms of COVID‐19 were recruited. Airway management including tracheal intubation and extubation was performed in a standard positive pressure operating room with aerosols detected using laser‐based particle image velocimetry to detect larger particles, and spectrometry with continuous air sampling to detect smaller particles. A total of 482,960 data points were assessed for complete procedures in three patients. Facemask ventilation, tracheal tube insertion and cuff inflation generated small particles 30–300 times above background noise that remained suspended in airflows and spread from the patient’s facial region throughout the confines of the operating theatre. Safe clinical practice of these procedures should reflect these particle profiles. This adds to data that inform decisions regarding the appropriate precautions to take in a real‐world setting.

Reducing Aerosolized Particles and Droplet Spread in Endoscopic Sinus Surgery during COVID-19

Objectives

The presence of high SARS‐Cov‐2 viral loads in the upper airway, including the potential for aerosolized transmission of viral particles, has generated significant concern amongst otolaryngologists worldwide, particularly those performing endoscopic sinus surgery (ESS). We evaluated a simple negative‐pressure mask technique to reduce viral exposure.

Methods

Two models simulating respiratory droplets >5–10 μm and fine respiratory nuclei <5 μm using fluorescein dye and wood smoke, respectively, were utilized in a fixed cadaveric study in a controlled environment. Using ultraviolet light, fluorescein droplet spread was assessed during simulated ESS with powered microdebrider and powered drilling. Wood smoke ejection was used to evaluate fine particulate escape from a negative‐pressure mask using digital subtraction image processing.

Results

The use of a negative‐pressure mask technique resulted in 98% reduction in the fine particulate aerosol simulation and eliminated larger respiratory droplet spread during simulated ESS, including during external drill activation.

Conclusions

As global ear, nose & throat (ENT) services resume routine elective operating, we demonstrate the potential use of a simple negative‐pressure mask technique to reduce the risk of viral exposure for the operator and theatre staff during ESS.

Level of Evidence

5 Laryngoscope, 131:956–960, 2021

Minimising aerosol spread during endoscopic sinus and skull base surgery. Experimental model evaluation of the efficacy of the microscope drape method

BACKGROUND

Endoscopic sinus and anterior skull base surgery is considered particularly high risk for severe acute respiratory syndrome coronavirus-2 transmission in the operating theatre setting. In this context, the use of a microscope drape method is proposed, to minimise aerosol spread in the wider operating theatre environment.

METHODS

The efficacy of the method is assessed with a simulation model, using a CMI Concept Air Trace MK2 smoke generator for aerosol generation and a Fluke 985 air particle counter to measure air particles sized 0.3-10 μm in the operating theatre environment.

RESULTS

Aerosol spread was contained almost to baseline levels with the application of the drape barrier and the negative pressure created using suction within the drape.

CONCLUSION

The method is an efficient adjunct that could reduce the risk of aerosol shedding and viral transmission to the operating theatre team. It potentially allows faster operating theatre turnover and more liberal use of powered instruments during endonasal surgery.

In vitro comparison of surgical techniques in times of the SARS-CoV-2 pandemic: electrocautery generates more droplets and aerosol than laser surgery or drilling

Introduction

Based on current knowledge, the SARS-CoV-2 is transmitted via droplet, aerosols and smear infection. Due to a confirmed high virus load in the upper respiratory tract of COVID-19 patients, there is a potential risk of infection for health care professionals when performing surgical procedures in this area. The aim of this study was the semi-quantitative comparison of ENT-typical interventions in the head and neck area with regard to particle and aerosol generation. These data can potentially contribute to a better risk assessment of aerogenic SARS-CoV-2-transmission caused by medical procedures.

Materials and methods

As a model, a test chamber was created to examine various typical surgical interventions on porcine soft and hard tissues. Simultaneously, particle and aerosol release were recorded and semi-quantitatively evaluated time-dependently. Five typical surgical intervention techniques (mechanical stress with a passive instrument with and without suction, CO₂ laser treatment, drilling and bipolar electrocoagulation) were examined and compared regarding resulting particle release.

Results

Neither aerosols nor particles could be detected during mechanical manipulation with and without suction. The use of laser technique showed considerable formation of aerosol. During drilling, mainly solid tissue particles were scattered into the environment (18.2 ± 15.7 particles/cm²/min). The strongest particle release was determined during electrocoagulation (77.2 ± 30.4 particles/cm²/min). The difference in particle release between electrocoagulation and drilling was significant (p < 0.05), while particle diameter was comparable. In addition, relevant amounts of aerosol were released during electrocoagulation (79.6% of the maximum flue gas emission during laser treatment).

Discussion

Our results demonstrated clear differences comparing surgical model interventions. In contrast to sole mechanical stress with passive instruments, all active instruments (laser, drilling and electrocoagulation) released particles and aerosols. Assuming that particle and aerosol exposure is clinically correlated to the risk of SARS-CoV-2-transmission from the patient to the physician, a potential risk for health care professionals for infection cannot be excluded. Especially electrocautery is frequently used for emergency treatment, e.g., nose bleeding. The use of this technique may, therefore, be considered particularly critical in potentially infectious patients. Alternative methods may be given preference and personal protective equipment should be used consequently.

Management of FDG avid Benign Sinonasal Schneiderian Papilloma: A Case Report and Review of the Literature

BACKGROUND

The inverted and oncocytic subtypes of sinonasal Schneiderian papillomas are benign tumors with possible rare malignant transformation and are typically managed with complete surgical resection and close follow-up. While computed tomography (CT) and magnetic resonance imaging (MRI) are mainstays in preoperative evaluation of bony invasion and soft tissue extension of the lesion, their imaging characteristics by 18F-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) is less well characterized.

OBJECTIVE

To describe the clinical presentation and management of a PET positive sinonasal lesion. To conduct a literature review of FDG uptake in benign sinonasal papillomas.

METHODS

Case report (n = 1) and literature review of similar cases (n = 32).

RESULTS

We report the case of a 69-year-old man presenting with an isolated left maxillary sinus mass with avid FDG uptake, discovered on PET/CT imaging. An endoscopic left maxillary mega-antrostomy provided successful definitive treatment for final pathologic diagnosis of oncocytic papilloma. Literature review of cases of sinonasal papillomas with avid FDG uptake found that oncocytic papillomas, on average, exhibit greater uptake than inverted papillomas and both may be mistaken as malignancies on PET.

CONCLUSION

While PET imaging demonstrating avid FDG uptake is associated with an increased risk of malignancy, it does not rule out the possibility of a benign sinonasal papilloma nor other benign inflammatory lesions. Particularly, oncocytic papillomas may have very high FDG uptake and mimic malignant lesions.

Droplet Exposure Risk to Providers From In-Office Flexible Laryngoscopy: A COVID-19 Simulation

To provide data on risk of respiratory droplets from common otolaryngologic procedures during the COVID-19 pandemic, a novel simulation of droplet exposure from flexible laryngoscopy was performed. After completion of a nasal symptom questionnaire, topical fluorescein spray was administered into the nasal and oropharynx of 10 healthy volunteers, who then underwent flexible laryngoscopy under 2 conditions: routine without provoked response and with prompted sneeze/cough. After each, droplets on the proceduralist and participant were counted under ultraviolet A light. Droplets were observed on 1 of 10 volunteers after routine laryngoscopy and 4 of 10 during laryngoscopy with sneeze/cough. A nasal symptom score based on congestion and rhinorrhea was significantly elevated among droplet producers after sneeze/cough (P = .0164). No droplets were observed on the provider. Overall, with adequate personal protective equipment, flexible laryngoscopy poses minimal droplet risk to providers. Nasal symptoms can identify patients more likely to produce droplets after sneeze/cough.

Droplet and Aerosol Generation With Endonasal Surgery: Methods to Mitigate Risk During the COVID-19 Pandemic

Objective

To define the aerosol and droplet risks associated with endonasal drilling and to identify mitigation strategies.

Study Design

Simulation series with fluorescent 3-dimensional (3D) printed sinonasal models and deidentified cadaveric heads.

Settings

Dedicated surgical laboratory.

Subjects and Methods

Cadaveric specimens irrigated with fluorescent tracer and fluorescent 3D-printed models were drilled. A cascade impactor was used to collect aerosols and small droplets of various aerodynamic diameters under 15 µm. Large droplet generation was measured by evaluating the field for fluorescent debris. Aerosol plumes through the nares were generated via nebulizer, and mitigation measures, including suction and SPIWay devices, nasal sheaths, were evaluated regarding reduction of aerosol escape from the nose.

Results

The drilling of cadaveric specimens without flexible suction generated aerosols ≤3.30 µm, and drilling of 3D sinonasal models consistently produced aerosols ≤14.1 µm. Mitigation with SPIWay or diameter-restricted SPIWay produced same results. There was minimal field contamination in the cadaveric models, 0% to 2.77% field tarp area, regardless of drill burr type or drilling location; cutting burr drilling without suction in the 3D model yielded the worst contamination field (36.1%), followed by coarse diamond drilling without suction (19.4%). The simple placement of a flexible suction instrument in the nasal cavity or nasopharynx led to complete elimination of all aerosols ≤14.1 µm, as evaluated by a cascade impactor positioned immediately at the nares.

Conclusion

Given the findings regarding aerosol risk reduction, we strongly recommend that physicians use a suction instrument in the nasal cavity or nasopharynx during endonasal surgery in the COVID-19 era.

Mitigation of Aerosols Generated During Rhinologic Surgery: A Pandemic-Era Cadaveric Simulation

OBJECTIVE

After significant restrictions initially due to the COVID-19 pandemic, otolaryngologists have begun resuming normal clinical practice. However, the risk of SARS-CoV-2 transmission to health care workers through aerosolization and airborne transmission during rhinologic surgery remains incompletely characterized. The objective of this study was to quantify the number concentrations of aerosols generated during rhinologic surgery with and without interventions involving 3 passive suction devices.

STUDY DESIGN

Cadaver simulation.

SETTING

Dedicated surgical laboratory.

SUBJECTS AND METHODS

In a simulation of rhinologic procedures with and without different passive suction interventions, the concentrations of generated aerosols in the particle size range of 0.30 to 10.0 µm were quantified with an optical particle sizer.

RESULTS

Functional endoscopic sinus surgery with and without microdebrider, high-speed powered drilling, use of an ultrasonic aspirator, and electrocautery all produced statistically significant increases in concentrations of aerosols of various sizes (P < .05). Powered drilling, ultrasonic aspirator, and electrocautery generated the highest concentration of aerosols, predominantly submicroparticles <1 µm. All interventions with a suction device were effective in reducing aerosols, though the surgical smoke evacuation system was the most effective passive suction method in 2 of the 5 surgical conditions with statistical significance (P < .05).

CONCLUSION

Significant aerosol concentrations were produced in the range of 0.30 to 10.0 µm during all rhinologic procedures in this cadaver simulation. Rhinologic surgery with a passive suction device results in significant mitigation of generated aerosols.