Hyperventilation During Manual Ventilation Can Be Reduced Using a Novel Ventilator but Not With Education Interventions.

INTRODUCTION: Traumatic brain injury (TBI) is the leading cause of combat casualties in modern war with an estimated 20% of casualties experiencing head injury. Since the release of the Brain Trauma Foundation's Guidelines for the Management of Severe Traumatic Brain Injury in 1995, recommendations for management of TBI have included the avoidance of routine hyperventilation. However, both published and anecdotal data suggest that many patients with TBI are inappropriately ventilated during transport, thereby increasing the risk of morbidity and mortality from secondary brain injury. MATERIALS AND METHODS: Enlisted Air Force personnel with prior emergency medical technician training completing a 3-week trauma course were evaluated on their ability to provide manual ventilation. Participants provided manual ventilation using either an in-situ endotracheal tube (ETT) or standard face mask on a standardized simulated patient manikin with TBI on the first and last days of the course. Manual ventilation was provided via a standard manual ventilator and a novel manual ventilator designed to limit tidal volume (VT) and respiratory rate (RR). Participants were given didactic and hands-on training on the third day of the course. Half of the participants were given simulator feedback during the hands-on training. All students provided 2 minutes of manual ventilation with each respirator. Data were collected on the breath-to-breath RR, VT, and peak airway pressures generated by the participant for each trial and were averaged for each trial. A minute ventilation (MV) was then derived from the calculated RR and VT. RESULTS: One hundred fifty-six personnel in the trauma course were evaluated in this study. Significant differences were found in the participant's performance with manual ventilation with the novel compared to the traditional ventilator. Before training, MV with the novel ventilator was less than with the traditional ventilator by 2.1 ± 0.4 L/min (P = .0003) and 1.6 ± 0.5 L/min (P = .0489) via ETT and face mask, respectively. This effect persisted after training with a difference between the devices of 1.8 ± 0.4 L/min (P = .0069) via ETT. Both traditional education interventions (didactics with hands-on training) and simulator-based feedback did not make a significant difference in participant's performance in delivering MV. CONCLUSIONS: The use of a novel ventilator that limits RR and VT may be useful in preventing hyperventilation in TBI patients. Didactic education and simulator-based feedback training may not have significant impact on improving ventilation practices in prehospital providers.

Construção e validação da escala de verificação da adesão às recomendações das Diretrizes Brasileiras de Ventilação Mecânica / Construction and validation of the scale for verifying adherence to the recom-mendations of The Brazilian Guidelines For Mechanical Ventilation / Construcción y validación de la escala para verificar la adherencia a las recomenda-ciones de Las Directrices Brasileñas Sobre Ventilación Mecánica

Objetivo: construir e validar uma escala de verificação da adesão às recomendações das Diretrizes Brasileiras de Ventilação Mecânica por profissionais da saúde. Método: estudo metodológico, conduzido no período entre setembro e dezembro de 2019 em um hospital público com 87 pacientes. Para a validação de conteúdo, adotou-se o Índice de Validação de Conteúdo; para a validade de critério, o Coeficiente de Correlação de Pearson; para a consistência interna, o alfa de Cronbach; e, para a confiabilidade interobservador, o Coeficiente Kappa e o Coeficiente de Correlação Intraclasse. Resultados: a escala identificou uma validade de conteúdo e consistência interna aceitável. A correlação de Pearson indicou uma correlação do escore de adesão com a saturação (r = 0,31; p≤0,005), o escore médio para o observador A e B resultou, respectivamente, em 88,89(±5,23) e 88,86(±5,34), e o intervalo de confiança foi de 0,96. Conclusão: a escala apresentou validade e confiabilidade para verificar a adesão às Diretrizes Brasileiras de Ventilação Mecânica dos profissionais.(AU)

Objective: to construct and validate a scale for verifying adherence to the recommendations of the Brazilian Guidelines for Mechanical Ventilation by healthcare professionals. Method: methodological study, conducted between September and December 2019 in a public hospital with 87 patients. For content validation, the Content Validation Index was adopted; for criterion validity, Pearson's Correlation Coefficient; for internal consistency, Cronbach's alpha; and, for interobserver reliability, the Kappa Coefficient, and the Intraclass Correlation Coefficient. Results: the scale identified acceptable content validity and internal consistency. Pearson's correlation indicated a correlation between adherence score and saturation (r = 0.31; p≤0.005), the average score for observer A and B resulted, respectively, in 88.89(±5.23) and 88.86(±5.34), and the confidence interval was 0.96. Conclusion: the scale showed validity and reliability to verify adherence to the Brazilian Guidelines for Mechanical Ventilation by professionals.(AU)

Objetivo: construir y validar una escala para verificar la adherencia a las recomendaciones de las directrices brasileñas sobre ventilación mecánica por parte de los profesionales de la salud. Método: estudio metodológico, realizado entre septiembre y diciembre de 2019 en un hospital público con 87 pacientes. Se adoptó el Índice de Validación de Contenido para la validación de contenido, para la validez de criterio, el Coeficiente de Correlación de Pearson, para la consistencia interna, el alfa de Cronbach y, para la fiabilidad interobservador, el Coeficiente Kappa y el Coeficiente de Correlación Intraclase. Resultados: la escala presentó una validez de contenido y una consistencia interna aceptables. La correlación de Pearson indicó una correlación de la puntuación de adherencia con la saturación (r = 0,31; p≤0,005), la puntuación media para el observador A y B resultó de 88,89(±5,23) y 88,86(±5,34), respectivamente, y el intervalo de confianza fue de 0,96. Conclusión: la escala presentó validez y confiabilidad para verificar la adherencia a las Directrices Brasileñas de Ventilación Mecánica de los profesionales.(AU)

Elastomeric Respirators for COVID-19 and the Next Respiratory Virus Pandemic: Essential Design Elements.

Respiratory viruses are transmitted via respiratory particles that are emitted when people breath, speak, cough, or sneeze. These particles span the size spectrum from visible droplets to airborne particles of hundreds of nanometers. Barrier face coverings ("cloth masks") and surgical masks are loose-fitting and provide limited protection from airborne particles since air passes around the edges of the mask as well as through the filtering material. Respirators, which fit tightly to the face, provide more effective respiratory protection. Although healthcare workers have relied primarily on disposable filtering facepiece respirators (such as N95) during the COVID-19 pandemic, reusable elastomeric respirators have significant potential advantages for the COVID-19 and future respiratory virus pandemics. However, currently available elastomeric respirators were not designed primarily for healthcare or pandemic use and require further development to improve their suitability for this application. The authors believe that the development, implementation, and stockpiling of improved elastomeric respirators should be an international public health priority.

The FDA Revokes Authorizations for Certain Respirators and Decontamination Systems.

Changes reflect replenished stockpiles of approved equipment.

Review of Anesthesia Versus Intensive Care Unit Ventilators and Ventilatory Strategies: COVID-19 Patient Management Implications.

The coronavirus disease 2019 (COVID-19) respiratory illness has increased the amount of people needing airway rescue and the support of mechanical ventilators. In doing so, the pandemic has increased the demand of healthcare professionals to manage these critically ill individuals. Certified Registered Nurse Anesthetists (CRNAs), who are trained experts in airway management and mechanical ventilation with experience in intensive care units (ICUs), rise to this challenge. However, many CRNAs may be unfamiliar with advancements in critical care ventilators. The purpose of this review is to provide a resource for CRNAs returning to the ICU to manage patients requiring invasive mechanical ventilation. The most common ventilator modes found in anesthesia machine ventilators and ICU ventilators are reviewed, as are the lung-protective ventilation strategies, including positive end-expiratory pressure, used to manage patients with COVID-19-induced acute respiratory distress syndrome. Adjuncts to mechanical ventilation, recruitment maneuvers, prone positioning, and extracorporeal membrane oxygenation are also reviewed. More research is needed concerning the management of COVID-19-infected patients, and CRNAs must become familiar with their ICU units' individual ventilator machine, but this brief review provides a good place to start for those returning to the ICU.

Performance and impact of disposable and reusable respirators for healthcare workers during pandemic respiratory disease: a rapid evidence review.

OBJECTIVES: To synthesise evidence concerning the range of filtering respirators suitable for patient care and guide the selection and use of different respirator types. DESIGN: Comparative analysis of international standards for respirators and rapid review of their performance and impact in healthcare. DATA SOURCES: Websites of international standards organisations, Medline and Embase, hand-searching of references and citations. STUDY SELECTION: Studies of healthcare workers (including students) using disposable or reusable respirators with a range of designs. We examined respirator performance, clinician adherence and performance, comfort and impact, and perceptions of use. RESULTS: We included standards from eight authorities across Europe, North and South America, Asia and Australasia and 39 research studies. There were four main findings. First, international standards for respirators apply across workplace settings and are broadly comparable across jurisdictions. Second, effective and safe respirator use depends on proper fitting and fit testing. Third, all respirator types carry a burden to the user of discomfort and interference with communication which may limit their safe use over long periods; studies suggest that they have little impact on specific clinical skills in the short term but there is limited evidence on the impact of prolonged wearing. Finally, some clinical activities, particularly chest compressions, reduce the performance of filtering facepiece respirators. CONCLUSION: A wide range of respirator types and models is available for use in patient care during respiratory pandemics. Careful consideration of performance and impact of respirators is needed to maximise protection of healthcare workers and minimise disruption to care.

Simultaneous ventilation in the Covid-19 pandemic. A bench study.

COVID-19 pandemic sets the healthcare system to a shortage of ventilators. We aimed at assessing tidal volume (VT) delivery and air recirculation during expiration when one ventilator is divided into 2 test-lungs. The study was performed in a research laboratory in a medical ICU of a University hospital. An ICU (V500) and a lower-level ventilator (Elisée 350) were attached to two test-lungs (QuickLung) through a dedicated flow-splitter. A 50 mL/cmH2O Compliance (C) and 5 cmH2O/L/s Resistance (R) were set in both A and B test-lungs (A C50R5 / B C50R5, step1), A C50-R20 / B C20-R20 (step 2), A C20-R20 / B C10-R20 (step 3), and A C50-R20 / B C20-R5 (step 4). Each ventilator was set in volume and pressure control mode to deliver 800mL VT. We assessed VT from a pneumotachograph placed immediately before each lung, pendelluft air, and expiratory resistance (circuit and valve). Values are median (1st-3rd quartiles) and compared between ventilators by non-parametric tests. Between Elisée 350 and V500 in volume control VT in A/B test- lungs were 381/387 vs. 412/433 mL in step 1, 501/270 vs. 492/370 mL in step 2, 509/237 vs. 496/332 mL in step 3, and 496/281 vs. 480/329 mL in step 4. In pressure control the corresponding values were 373/336 vs. 430/414 mL, 416/185 vs. 322/234 mL, 193/108 vs. 176/ 92 mL and 422/201 vs. 481/329mL, respectively (P<0.001 between ventilators at each step for each volume). Pendelluft air volume ranged between 0.7 to 37.8 ml and negatively correlated with expiratory resistance in steps 2 and 3. The lower-level ventilator performed closely to the ICU ventilator. In the clinical setting, these findings suggest that, due to dependence of VT to C, pressure control should be preferred to maintain adequate VT at least in one patient when C and/or R changes abruptly and monitoring of VT should be done carefully. Increasing expiratory resistance should reduce pendelluft volume.

Heterogeneous approach to nebulization of antimicrobial agents in mechanically ventilated adults in a German tertiary care hospital: a cross-sectional survey.

There is lack of standardization of practices and limited evidence on efficacy and safety of nebulization of antimicrobials. We sought to determine inhalation practices in one tertiary care hospital by performing a cross-sectional survey. Eleven adult ICUs were included in the analysis. Three units followed established protocols. Ventilation circuit filters were exchanged at least daily in all but one units. Dosages of aminoglycosides and CMS depended on indication and unit. Nebulization of antimicrobials was generally regarded as safe and efficacious. Our data indicate that approach to nebulization of antimicrobials may be heterogeneous even in a single center.

Human factors/ergonomics to support the design and testing of rapidly manufactured ventilators in the UK during the COVID-19 pandemic.

BACKGROUND: This paper describes a rapid response project from the Chartered Institute of Ergonomics & Human Factors (CIEHF) to support the design, development, usability testing and operation of new ventilators as part of the UK response during the COVID-19 pandemic. METHOD: A five-step approach was taken to (1) assess the COVID-19 situation and decide to formulate a response; (2) mobilise and coordinate Human Factors/Ergonomics (HFE) specialists; (3) ideate, with HFE specialists collaborating to identify, analyse the issues and opportunities, and develop strategies, plans and processes; (4) generate outputs and solutions; and (5) respond to the COVID-19 situation via targeted support and guidance. RESULTS: The response for the rapidly manufactured ventilator systems (RMVS) has been used to influence both strategy and practice to address concerns about changing safety standards and the detailed design procedure with RMVS manufacturers. CONCLUSION: The documents are part of a wider collection of HFE advice which is available on the CIEHF COVID-19 website (https://covid19.ergonomics.org.uk/).

The US Strategic National Stockpile Ventilators in Coronavirus Disease 2019: A Comparison of Functionality and Analysis Regarding the Emergency Purchase of 200,000 Devices.

BACKGROUND: Early in the coronavirus disease 2019 (COVID-19) pandemic, there was serious concern that the United States would encounter a shortfall of mechanical ventilators. In response, the US government, using the Defense Production Act, ordered the development of 200,000 ventilators from 11 different manufacturers. These ventilators have different capabilities, and whether all are able to support COVID-19 patients is not evident. RESEARCH QUESTION: Evaluate ventilator requirements for affected COVID-19 patients, assess the clinical performance of current US Strategic National Stockpile (SNS) ventilators employed during the pandemic, and finally, compare ordered ventilators' functionality based on COVID-19 patient needs. STUDY DESIGN AND METHODS: Current published literature, publicly available documents, and lay press articles were reviewed by a diverse team of disaster experts. Data were assembled into tabular format, which formed the basis for analysis and future recommendations. RESULTS: COVID-19 patients often develop severe hypoxemic acute respiratory failure and adult respiratory defense syndrome (ARDS), requiring high levels of ventilator support. Current SNS ventilators were unable to fully support all COVID-19 patients, and only approximately half of newly ordered ventilators have the capacity to support the most severely affected patients; ventilators with less capacity for providing high-level support are still of significant value in caring for many patients. INTERPRETATION: Current SNS ventilators and those on order are capable of supporting most but not all COVID-19 patients. Technologic, logistic, and educational challenges encountered from current SNS ventilators are summarized, with potential next-generation SNS ventilator updates offered.

COVID-19: smoke testing of surgical mask and respirators.

BACKGROUND: Fluid Resistant Surgical Masks have been implemented in UK personal protective equipment (PPE) guidelines for COVID-19 for all care sites that do not include aerosol-generating procedures (AGPs). FFP3 masks are used in AGP areas. Concerns from the ENT and plastic surgery communities out with intensive care units have questioned this policy. Emerging evidence on cough clouds and health care worker deaths has suggested that a review is required. AIMS: To test the efficacy of Fluid Resistant Surgical Mask with and without adaptions for respiratory protection. To test the efficacy of FFP and FFP3 regarding fit testing and usage. METHODS: A smoke chamber test of 5 min to model an 8-h working shift of exposure while wearing UK guideline PPE using an inspiratory breathing mouthpiece under the mask. Photographic data were used for comparison. RESULTS: The Fluid Resistant Surgical Mask gave no protection to inhaled smoke particles. Modifications with tape and three mask layers gave slight benefit but were not considered practical. FFP3 gave complete protection to inhaled smoke but strap tension needs to be 'just right' to prevent facial trauma. Facial barrier creams are an infection risk. CONCLUSIONS: Surgical masks give no protection to respirable particles. Emerging evidence on cough clouds and health care worker deaths suggests the implementation of a precautionary policy of FFP3 for all locations exposed to symptomatic or diagnosed COVID-19 patients. PPE fit testing and usage policy need to improve to include daily buddy checks for FFP3 users.

Risks of emergency use authorizations for medical products during outbreak situations: a COVID-19 case study.

BACKGROUND: The world is facing an unprecedented outbreak affecting all aspects of human lives which is caused by the COVID-19 pandemic. Due to the virus novelty, healthcare systems are challenged by a high rate of patients and the shortage of medical products. To address an increased need for essential medical products, national authorities, worldwide, made various legislative concessions. This has led to essential medical products being produced by automotive, textile and other companies from various industries and approved under the emergency use authorizations or legal concessions of national regulatory bodies. This paper presents a narrative commentary of the available documentation on emergency use authorizations and legal concessions for medical products during COVID-19 pandemic. METHODOLOGY: The basis for narrative commentary includes scientific articles published in Web of Science, Scopus, PubMed and Embase databases, official publications of international organizations: Food and Drug Agency (FDA), World Health Organisation (WHO), World Bank and United Nations (UN), and national regulatory agency reports in native languages (English, German, Bosnian, and Croatian) published from November 1, 2019 to May 1, 2020. This paper focuses on three types of essential medical products: mechanical ventilators, personal protective equipment (PPE) and diagnostic tests. Evidence-informed commentary of available data and potential identified risks of emergency use authorizations and legal concessions is presented. DISCUSSION: It is recognized that now more than ever, raising global awareness and knowledge about the importance of respecting the essential requirements is needed to guarantee the appropriate quality, performance and safety of medical products, especially during outbreak situation, such as the COVID-19 pandemic. Emergency use authorizations for production, import and approval of medical products should be strictly specified and clearly targeted from case to case and should not be general or universal for all medical products, because all of them are associated with different risk level. CONCLUSION: Presented considerations and experiences should be taken as a guide for all possible future outbreak situations to prevent improvised reactions of national regulatory bodies.

N95 mask reuse in a major urban hospital: COVID-19 response process and procedure.

BACKGROUND: The shortage of single-use N95 respirator masks (NRMs) during the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has prompted consideration of NRM recycling to extend limited stocks by healthcare providers and facilities. AIM: To assess potential reuse via autoclaving of NRMs worn daily in a major urban Canadian hospital. METHODS: NRM reusability was assessed following collection from volunteer staff after 2-8 h use, sterilization by autoclaving and PortaCount fit testing. A workflow was developed for reprocessing hundreds of NRMs daily. FINDINGS: Used NRMs passed fit testing after autoclaving once, with 86% passing a second reuse/autoclave cycle. A separate cohort of used masks pre-warmed before autoclaving passed fit testing. To recycle 200-1000 NRMs daily, procedures for collection, sterilization and re-distribution were developed to minimize particle aerosolization risk during NRM handling, to reject NRM showing obvious wear, and to promote adoption by staff. NRM recovery ranged from 49% to 80% across 12 collection cycles. CONCLUSION: Reuse of NRMs is feasible in major hospitals and other healthcare facilities. In sharp contrast to studies of unused NRMs passing fit testing after 10 autoclave cycles, we show that daily wear substantially reduces NRM fit, limiting reuse to a single cycle, but still increasing NRM stocks by ∼66%. Such reuse requires development of a comprehensive plan that includes communication across staffing levels, from front-line workers to hospital administration, to increase the collection, acceptance of and adherence to sterilization processes for NRM recovery.

Stockpiled N95 respirator/surgical mask release beyond manufacturer-designated shelf-life: a French experience.

BACKGROUND: To reduce the shortage of N95 respirators and surgical masks during the COVID-19 pandemic, stockpiled equipment beyond its expiry date could be released. AIM: Centralized testing of batches of expired surgical masks and N95 for safe distribution to hospital departments saving users time. METHODS: Tests of compliance with health authority directives were developed and carried out on 175 batches of N95 masks and 31 batches of surgical masks from 12th March 2020 to 16 April 2020. Five quality-control tests were performed on batch samples to check: packaging integrity, mask appearance, breaking strength of elastic ties and strength of nose clip test, and face-fit. FINDINGS: Forty-nine per cent of FFP2 mask batches were compliant with directives, 32% of batches were compliant but with some concerns and 19% of batches were non-compliant. For surgical masks, 58% of batches were compliant, 39% of batches compliant but with concerns and 3% of batches were non-compliant. CONCLUSION: The main areas of non-compliance were the breaking strength of the elastic ties and the nose clip but these alone were not considered to make the masks unacceptable. Only mask appearance and face-fit results were decisive non-compliance criteria.

Governo de São Paulo vai receber mais 3 mil respiradores

Saiba mais em: www.saopaulo.sp.gov.br/coronavirus/planosp

Autoclave sterilization and ethanol treatment of re-used surgical masks and N95 respirators during COVID-19: impact on their performance and integrity.

BACKGROUND: An exceptionally high demand for surgical masks and N95 filtering facepiece respirators (FFRs) during the COVID-19 pandemic has considerably exceeded their supply. These disposable devices are generally not approved for routine decontamination and re-use as a standard of care, while this practice has widely occurred in hospitals. The US Centers for Disease Control and Prevention allowed it "as a crisis capacity strategy". However, limited testing was conducted on the impact of specific decontamination methods on the performance of N95 FFRs and no data was presented for surgical masks. AIM: We evaluated common surgical masks and N95 respirators with respect to the changes in their performance and integrity resulting from autoclave sterilization and a 70% ethanol treatment; these methods are frequently utilized for re-used filtering facepieces in hospitals. METHODS: The filter collection efficiency and pressure drop were determined for unused masks and N95 FFRs, and for those subjected to the treatments in a variety of ways. The collection efficiency was measured for particles of approximately 0.037-3.2 µm to represent aerosolized single viruses, their agglomerates, bacteria and larger particle carriers. FINDINGS: The initial collection efficiency and the filter breathability may be compromised by sterilization in an autoclave and ethanol treatment. The effect depends on a protective device, particle size, breathing flow rate, type of treatment and other factors. Additionally, physical damages were observed in N95 respirators after autoclaving. CONCLUSION: Strategies advocating decontamination and re-use of filtering facepieces in hospitals should be re-assessed considering the data obtained in this study.

Challenges in Preparing and Managing the Critical Care Services for a Large Urban Area During COVID-19 Outbreak: Perspective From Delhi.

The coronavirus disease-2019 (COVID-19) pandemic has put healthcare services all over the world into a challenging situation. The contagious nature of the disease and the respiratory failure necessitating ventilatory care of these patients have put extra burden on intensive care unit (ICU) services. India has been no exception; by March 2020, the number of COVID-19 patients started increasing in India. This article describes the measures taken and challenges faced in creating ample ICU bed capacity to cater to the anticipated load of patients in the state of Delhi, India, as a result of the COVID-19 pandemic. The main challenges faced, among others, were estimating the number of ICU beds to be created; deciding on dedicated hospitals to treat COVID-19 patients; procuring ventilators, personal protective equipment, and other related material; mobilizing human resources and providing their training; and providing isolated in-house accommodations to the staff on duty. The authors acknowledge and agree that the methodology proposed in this article is but one way of approaching this difficult scenario and that there could be other, perhaps better, methods of dealing with such a problem.