Dataset Information

The effect of an air purifier on aerosol generation measurements during clinical motility testing.

ABSTRACT:

Background

Aerosol spread is key to interpret the risk of viral contamination during clinical procedures such as esophageal high-resolution manometry (HRM). Installing an air purifier seems a legitimate strategy, but this has recently been questioned.

Methods

Patients undergoing an HRM procedure at the Leuven University Hospital were included in this clinical study. All subjects had to wear a surgical mask which was only lowered beneath the nose during the placement and removal of the nasogastric catheter. The number of aerosol particles was measured by a Lasair^® II Particle Counter to obtain data about different particles sizes: 0.3; 0.5; 1.0; 3.0; 5.0; and 10.0 µm. Measurements were done immediately before the placement and the removal of the HRM catheter, and one and 5 min after. A portable air purifier with high-efficiency particle air filters was installed in the hospital room.

Key results

Thirteen patients underwent a manometry examination. The amount of 0.3 µm-sized particles was unaffected during the whole procedure. The larger particle sizes (1.0; 3.0; 5.0; and 10.0 µm) decreased when the catheter was positioned, but not 0.5 µm. During the HRM measurements itself, these numbers decreased further. Yet, 1 min after catheter removal a significant elevation of particles was seen, which did not recover within 5 min.

Conclusions & interferences

Based on this study, there is no evidence that filtration systems reduce aerosol particles properly during a clinical investigation.

SUBMITTER: Verbeure W

PROVIDER: S-EPMC8420584 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

The effect of an air purifier on aerosol generation measurements during clinical motility testing.

Verbeure Wout W Geeraerts Annelies A Huang I-Hsuan IH Timmermans Lien L Tóth Joran J Geysen Hannelore H Cools Louise L Carbone Florencia F Schol Jolien J Devriese Herman H Haesaerts Rico R Mori Hideki H Vanuytsel Tim T Tack Jan J

Neurogastroenterology and motility 20210802 4

<h4>Background</h4>Aerosol spread is key to interpret the risk of viral contamination during clinical procedures such as esophageal high-resolution manometry (HRM). Installing an air purifier seems a legitimate strategy, but this has recently been questioned.<h4>Methods</h4>Patients undergoing an HRM procedure at the Leuven University Hospital were included in this clinical study. All subjects had to wear a surgical mask which was only lowered beneath the nose during the placement and removal of ...[more]

PMID: 34342092

Similar Datasets

Project description:BackgroundDuring medical procedures with the potential to produce aerosols such as bronchoscopy, intubation, or CPR, health-care workers (HCWs) may be exposed to infectious bioaerosols. This scenario is of particular concern when high consequence pathogens such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are circulating. Thousands of HCWs have been infected with SARS-CoV-2. However, the determinants of aerosol generation during medical procedures and their relative risk to HCWs remain poorly characterized.Research questionThe goal of this study was to characterize aerosols produced during airway intubation by using an uninfected translational animal model and in human subjects undergoing elective aerosol-generating procedures. The study also determined the particle size distribution of generated particles.Study design and methodsAerosol generation was measured during highly controlled experimental (pig) intubations (N = 16) and elective bronchoscopies in uninfected patients (N = 49) using an optical particle counter. Recovery of normal respiratory flora was used as a surrogate for pathogen dispersion.ResultsThere was a small but significant (P = .03) decrease in 0.3 μm size particles during highly controlled pig intubations compared with baseline. The concentration of 1.0 μm and 5.0 μm aerosol particles did not significantly change, although oral bacteria were collected from the air. For elective patient bronchoscopies, there was a significant decrease in the generation of larger particles (1.0 μm and 5.0 μm) compared with baseline (P < .01); however, 18 of 39 (46%) patients showed increased aerosol production in 0.3 μm size particles, four of whom exhibited measurable increases.InterpretationAlthough the total amount of aerosols produced during intubation and bronchoscopy did not increase significantly relative to preprocedural levels, a small number of participants exhibited a measurable increase in submicron particle emission, meriting further research to delineate determinants of fine particle production during aerosol-generating procedures.

Project description:BackgroundIntubation, laryngoscopy, and extubation are considered highly aerosol-generating procedures, and additional safety protocols are used during COVID-19 pandemic in these procedures. However, previous studies are mainly experimental and have neither analyzed staff exposure to aerosol generation in the real-life operating room environment nor compared the exposure to aerosol concentrations generated during normal patient care. To assess operational staff exposure to potentially infectious particle generation during general anesthesia, we measured particle concentration and size distribution with patients undergoing surgery with Optical Particle Sizer.MethodsA single-center observative multidisciplinary clinical study in Helsinki University Hospital with 39 adult patients who underwent general anesthesia with tracheal intubation. Mean particle concentrations during different anesthesia procedures were statistically compared with cough control data collected from 37 volunteers to assess the differences in particle generation.ResultsThis study measured 25 preoxygenations, 30 mask ventilations, 28 intubations, and 24 extubations. The highest total aerosol concentration of 1153 particles (p)/cm³ was observed during mask ventilation. Preoxygenations, mask ventilations, and extubations as well as uncomplicated intubations generated mean aerosol concentrations statistically comparable to coughing. It is noteworthy that difficult intubation generated significantly fewer aerosols than either uncomplicated intubation (p = .007) or coughing (p = 0.006).ConclusionsAnesthesia induction generates mainly small (<1 µm) aerosol particles. Based on our results, general anesthesia procedures are not highly aerosol-generating compared with coughing. Thus, their definition as high-risk aerosol-generating procedures should be re-evaluated due to comparable exposures during normal patient care.Implication statementThe list of aerosol-generating procedures guides the use of protective equipments in hospitals. Intubation is listed as a high-risk aerosol-generating procedure, however, aerosol generation has not been measured thoroughly. We measured aerosol generation during general anesthesia. None of the general anesthesia procedures generated statistically more aerosols than coughing and thus should not be considered as higher risk compared to normal respiratory activities.

Project description:BackgroundsDental procedures involving drilling and grinding can produce a significant amount of suspended aerosol particles (PM) and bioaerosols. This study aims to analyze the size and concentration of aerosol particles generated during drilling and to investigate the effectiveness of two air exchange systems, namely forceful suction (FS) and air disinfection machines (DM), in removing PM.MethodsFor this study, 100 extracted permanent teeth were collected and divided into three groups: without suction (n = 50), suction with forceful suction (n = 25), and suction with air disinfection machines (n = 25). The removal rate of suspended aerosol particles was analyzed using particle counters and air data multimeter.ResultsWhen drilling and grinding were performed without vacuum, 0.75% of the aerosol particles generated were PM2.5-10, 78.25% of total suspended aerosol particles (TSP) were PM2.5, and 98.68% of TSP were PM1. The nanoanalyzer measurements revealed that the aerodynamic diameter of most aerosol particles was below 60 nm, with an average particle diameter of 52.61 nm and an average concentration of 2.6*1011 ultrafine aerosol particles. The air change per hour (ACH) was significantly lower in the air disinfection machines group compared to the forceful suction group. Additionally, the number of aerosol particles and mass concentration was significantly lower in the air disinfection machines group compared to the forceful suction group in terms of PM2.5 levels. However, the forceful suction group also reduced the mass concentration in PM10 level than the air disinfection machines group.ConclusionIn conclusion, the air exchange system can reduce the aerosol particles generated during drilling and grinding. Comparing the two air exchange systems, it was found that the air disinfection machines group reduces the number of aerosol particles and mass concentration in PM2.5 levels, while the forceful suction group reduces the mass concentration in PM10 level.

Project description:It is unclear if cardiopulmonary resuscitation is an aerosol-generating procedure and whether this poses a risk of airborne disease transmission to healthcare workers and bystanders. Use of airborne transmission precautions during cardiopulmonary resuscitation may confer rescuer protection but risks patient harm due to delays in commencing treatment. To quantify the risk of respiratory aerosol generation during cardiopulmonary resuscitation in humans, we conducted an aerosol monitoring study during out-of-hospital cardiac arrests. Exhaled aerosol was recorded using an optical particle sizer spectrometer connected to the breathing system. Aerosol produced during resuscitation was compared with that produced by control participants under general anaesthesia ventilated with an equivalent respiratory pattern to cardiopulmonary resuscitation. A porcine cardiac arrest model was used to determine the independent contributions of ventilatory breaths, chest compressions and external cardiac defibrillation to aerosol generation. Time-series analysis of participants with cardiac arrest (n = 18) demonstrated a repeating waveform of respiratory aerosol that mapped to specific components of resuscitation. Very high peak aerosol concentrations were generated during ventilation of participants with cardiac arrest with median (IQR [range]) 17,926 (5546-59,209 [1523-242,648]) particles.l-1 , which were 24-fold greater than in control participants under general anaesthesia (744 (309-2106 [23-9099]) particles.l-1 , p < 0.001, n = 16). A substantial rise in aerosol also occurred with cardiac defibrillation and chest compressions. In a complimentary porcine model of cardiac arrest, aerosol recordings showed a strikingly similar profile to the human data. Time-averaged aerosol concentrations during ventilation were approximately 270-fold higher than before cardiac arrest (19,410 (2307-41,017 [104-136,025]) vs. 72 (41-136 [23-268]) particles.l-1 , p = 0.008). The porcine model also confirmed that both defibrillation and chest compressions generate high concentrations of aerosol independent of, but synergistic with, ventilation. In conclusion, multiple components of cardiopulmonary resuscitation generate high concentrations of respiratory aerosol. We recommend that airborne transmission precautions are warranted in the setting of high-risk pathogens, until the airway is secured with an airway device and breathing system with a filter.

Project description:ImportanceDespite growing scientific knowledge and research, it is still unknown if office flexible laryngoscopy (FL) is aerosol generating and thereby potentially increases the risk of SARS-CoV-2 transmission. The limited literature that exists is conflicting, precluding formal conclusions.ObjectiveTo determine whether FL is aerosol generating.Design, setting, and participantsThis prospective cohort study included 134 patients seen in the otolaryngology clinic at a single tertiary care academic institution between February and May 2021. Two optical particle sizer instruments were used, quantifying particles ranging from 0.02 μm to 5 μm. Measurements were taken every 30 seconds, with sample periods of 15 seconds throughout the patient encounter. Instruments were located 12 inches from the patient's nares. Timing of events was recorded, including the start and end of physical examination, topical spray administration, start and end of laryngoscopy, and other potential aerosol-generating events (eg, coughing, sneezing). Data analysis was performed from February to May 2021.ExposuresOffice examination and office FL.Main outcomes and measuresBayesian online change point detection (OCPD) algorithm was used to detect significant change points (CPs) in this time-series data. The primary outcome was significant CP after FL compared with baseline physiologic variations, such as breathing and phonation.ResultsData were collected from 134 patients between February and May 2021. Ninety-one encounters involved FL. Of this group, 51 patients (56%) wore no mask over their mouth during FL. There was no statistically significant CP in either visits involving FL or visits where FL was not performed. Use of nasal spray did not result in CP in aerosol levels. Overall, neither the number of people present in the examination room, masks over patients' mouth, the duration of the visit, nor the duration of FL were associated with mean aerosol counts, regardless of the exposure. For larger aerosol sizes (≥1 μm), however, rooms with higher air exchange rates had significantly higher reductions in mean aerosol counts for visits involving FL.Conclusions and relevanceThe findings of this cohort study support that FL, including topical spray administration, is not a significant aerosol-generating procedure. The Bayesian OCPD model has a promising application for future aerosol studies in otolaryngology.

Dataset Information

The effect of an air purifier on aerosol generation measurements during clinical motility testing.

Background

Methods

Key results

Conclusions & interferences

Publications

The effect of an air purifier on aerosol generation measurements during clinical motility testing.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets