scholarly journals Quantification of aerosol dispersal from suspected aerosol generating procedures

2021 ◽  
pp. 00206-2021
Author(s):  
Runar Strand-Amundsen ◽  
Christian Tronstad ◽  
Ole Elvebakk ◽  
Tormod Martinsen ◽  
Marius Dybwad ◽  
...  

BackgroundOxygen delivering modalities like humidified high-flow nasal cannula (HFNC) and non-invasive positive-pressure ventilation (NIV) are suspected of generating aerosols that may contribute to transmission of disease such as COVID-19. We sought to assess if these modalities lead to increased aerosol dispersal compared to the use of non-humidified low-flow nasal cannula oxygen treatment (LFNC).MethodsAerosol dispersal from 20 healthy volunteers using HFNC, LFNC and NIV oxygen treatment was measured in a controlled chamber. We investigated effects related to coughing and using a surgical facemask in combination with the oxygen delivering modalities. An aerodynamic particle sizer measured aerosol particles (APS3321, 0.3–20 µm) directly in front of the subjects, while a mesh of smaller particle sensors (SPS30, 0.3–10 µm) was distributed in the test chamber.ResultsNon-productive coughing led to significant increases in particle dispersal close to the face when using LFNC and HFNC but not when using NIV. HFNC or NIV did not lead to a statistically significant increase in aerosol dispersal compared to LFNC. With non-productive cough in a room without air changes, there was a significant drop in particle levels between 100 cm and 180 cm from the subjects.ConclusionsOur results indicate that using HFNC and NIV does not lead to increased aerosol dispersal compared to low-flow oxygen treatment, except in rare cases. For a subject with non-productive cough, NIV with double-limb circuit and non-vented mask may be a favourable choice to reduce the risk for aerosol spread.

JMS SKIMS ◽  
2020 ◽  
Vol 23 (3) ◽  
Author(s):  
Tajamul Hussain Shah ◽  
Suhail Mantoo ◽  
Rafi Ahmad Jan

High Flow Nasal Cannula Oxygenation The current pandemic of COVID-19 caused by novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) tested the healthcare infrastructure throughout the globe at all possible levels. Early reports suggest about 20% of patients infected with SARS-CoV-2 require hospitalization and 5-8% require admission to intensive care unit (ICU) due to severe disease.Supplementation of oxygen provided by various conventional oxygen therapy (COT) devices (like nasal prongs, face mask, venture mask or non-rebreather mask) may not be sufficient in cases of worsening respiratory failure. One form of escalating respiratory support in such patients is a high flow nasal oxygenation device. High flow nasal cannula oxygenation (HFNC) is a form of non invasive respiratory support. It acts as a bridge between low flow devices and non invasive ventilation and may reduce the need for intubation.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Alaa Masry ◽  
Nuha A. M. A. Nimeri ◽  
Olfa Koobar ◽  
Samer Hammoudeh ◽  
Prem Chandra ◽  
...  

Abstract Introduction Respiratory Distress Syndrome (RDS) is a common cause of neonatal morbidity and mortality in premature newborns. In this study, we aim to compare the reintubation rate in preterm babies with RDS who were extubated to Nasal Continuous Positive Airway Pressure (NCPAP) versus those extubated to Nasal Intermittent Positive Pressure Ventilation (NIPPV). Methods This is a retrospective study conducted in the Neonatal Intensive Care Unit (NICU) of Women’s Wellness and Research Center (WWRC), Doha, Qatar. The medical files (n = 220) of ventilated preterm infants with gestational age ranging between 28 weeks 0 days and 36 weeks + 6 days gestation and extubated to non-invasive respiratory support (whether NCPAP, NIPPV, or Nasal Cannula) during the period from January 2016 to December 2017 were reviewed. Results From the study group of 220 babies, n = 97 (44%) babies were extubated to CPAP, n = 77 (35%) were extubated to NIPPV, and n = 46 (21%) babies were extubated to Nasal Cannula (NC). Out of the n = 220 babies, 18 (8.2%) were reintubated within 1 week after extubation. 14 of the 18 (77.8%) were reintubated within 48 h of extubation. Eleven babies needed reintubation after being extubated to NCPAP (11.2%) and seven were reintubated after extubation to NIPPV (9.2%), none of those who were extubated to NC required reintubation (P = 0.203). The reintubation rate was not affected by extubation to any form of non-invasive ventilation (P = 0.625). The mode of ventilation before extubation does not affect the reintubation rate (P = 0.877). The presence of PDA and NEC was strongly associated with reintubation which increased by two and four-folds respectively in those morbidities. There is an increased risk of reintubation with babies suffering from NEC and BPD and this was associated with an increased risk of hospital stay with a P-value ranging (from 0.02–0.003). Using multivariate logistic regression, NEC the NEC (OR = 5.52, 95% CI 1.26, 24.11, P = 0.023) and the vaginal delivery (OR = 0.23, 95% CI 0.07, 0.78, P = 0.018) remained significantly associated with reintubation. Conclusion Reintubation rates were less with NIPPV when compared with NCPAP, however, this difference was not statistically significant. This study highlights the need for further research studies with a larger number of neonates in different gestational ages birth weight categories. Ascertaining this information will provide valuable data for the factors that contribute to re-intubation rates and influence the decision-making and management of RDS patients in the future.


Author(s):  
Grenville Fox ◽  
Nicholas Hoque ◽  
Timothy Watts

This chapter includes sections on various modes of both invasive (i.e. via an endotracheal tube) and non-invasive respiratory support in neonates, including conventional ventilation, volume-targeted ventilation, high-frequency oscillatory ventilation (HFOV), extracorporeal membrane oxygenation (ECMO), nasal continuous positive airways pressure (nCPAP), nasal intermittent positive pressure ventilation (nIPPV), and high and low-flow nasal cannula oxygen. There is also a brief section on the care of babies with a tracheostomy as well as management of babies requiring home oxygen. Reference is made to the most recent European Consensus Guidelines. A separate chapter on neonatal respiratory problems (Chapter 7) gives further detail on common lung pathologies requiring respiratory support in neonates.


Author(s):  
Joshua Gonzales ◽  
Kevin Collins ◽  
Christopher Russian

Purpose: The aim of this narrative review is to outline the mechanism of action of HFNC therapy, the clinical benefits of its use, cautions of its clinical application and limitations of previous research. Methods: A literature review was conducted using the following databases as sources: Medline, PubMed, and Google Scholar. Only publications written in English were used in this clinical review. Keywords used in the search included the following: high-flow nasal cannula, heated humidified oxygen, oxygen therapy, non-invasive ventilation, and respiratory failure. Results: The literature reveals HFNC therapy significantly decreased the use of mechanical ventilation (invasive or non-invasive) in patients experiencing respiratory failure. HFNC therapy was better tolerated by patients and decreased the patient’s work of breathing when compared to a conventional oxygen therapy (i.e., non-rebreather oxygen mask). Other clinical benefits of using HFNC when changing a patient from conventional facemask oxygen therapy to a HFNC device are significant improvements in PaO2, respiratory rate and overall comfort. Conclusions: High flow nasal cannula (HFNC) therapy serves as an alternative to conventional oxygen therapy to deliver elevated concentrations of oxygen to patients experiencing acute respiratory failure. Information detailed in this article suggests HFNC therapy is an effective therapy for improving a patient’s oxygenation status when experiencing acute respiratory failure in adults. The literature reveals, it is reasonable to initiate HFNC in adults with acute hypoxemic respiratory failure without hypercapnia, as an alternative to standard oxygen therapy or noninvasive positive pressure ventilation.


Author(s):  
Dany E Weisz ◽  
Eugene Yoon ◽  
Michael Dunn ◽  
Julie Emberley ◽  
Amit Mukerji ◽  
...  

ObjectiveTo evaluate annual trends in the administration and duration of respiratory support among preterm infants.DesignRetrospective cohort study.SettingTertiary neonatal intensive care units in the Canadian Neonatal Network.Patients8881 extremely preterm infants born from 2010 to 2017 treated with endotracheal and/or non-invasive positive pressure support (PPS).Main outcome measuresCompeting risks methods were used to investigate the outcomes of mortality and time to first successful extubation, definitive extubation, weaning off PPS, and weaning PPS and/or low-flow oxygen, according to gestational age (GA). Cox proportional hazards and regression models were fitted to evaluate the trend in duration of respiratory support, survival and surfactant treatment over the study period.ResultsThe percentages of infants who died or were weaned from respiratory support were presented graphically over time by GA. Advancing GA was associated with ordinally earlier weaning from respiratory support. Year over year, infants born at 23 weeks were initially and definitively weaned from endotracheal and all PPS earlier (HR 1.06, 95% CI 1.01 to 1.11, for all outcomes), while survival simultaneously increased (OR 1.11, 95% CI 1.03 to 1.18). Infants born at 26 and 27 weeks remained on non-invasive PPS longer (HR 0.97, 95% CI 0.95 to 0.98 and HR 0.97, 95% CI 0.95 to 0.99, respectively). Early surfactant treatment declined among infants born at 24–27 weeks GA.ConclusionsInfants at the borderline of viability have experienced improved survival and earlier weaning from all forms of PPS, while those born at 26 and 27 weeks are spending more time on PPS in recent years. GA-based estimates of the duration of respiratory support and survival may assist in counselling, benchmarking, quality improvement and resource planning.


Sign in / Sign up

Export Citation Format

Share Document