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The Cochrane Database of Systematic... Apr 2020In epidemics of highly infectious diseases, such as Ebola, severe acute respiratory syndrome (SARS), or coronavirus (COVID-19), healthcare workers (HCW) are at much... (Meta-Analysis)
Meta-Analysis
BACKGROUND
In epidemics of highly infectious diseases, such as Ebola, severe acute respiratory syndrome (SARS), or coronavirus (COVID-19), healthcare workers (HCW) are at much greater risk of infection than the general population, due to their contact with patients' contaminated body fluids. Personal protective equipment (PPE) can reduce the risk by covering exposed body parts. It is unclear which type of PPE protects best, what is the best way to put PPE on (i.e. donning) or to remove PPE (i.e. doffing), and how to train HCWs to use PPE as instructed.
OBJECTIVES
To evaluate which type of full-body PPE and which method of donning or doffing PPE have the least risk of contamination or infection for HCW, and which training methods increase compliance with PPE protocols.
SEARCH METHODS
We searched CENTRAL, MEDLINE, Embase and CINAHL to 20 March 2020.
SELECTION CRITERIA
We included all controlled studies that evaluated the effect of full-body PPE used by HCW exposed to highly infectious diseases, on the risk of infection, contamination, or noncompliance with protocols. We also included studies that compared the effect of various ways of donning or doffing PPE, and the effects of training on the same outcomes.
DATA COLLECTION AND ANALYSIS
Two review authors independently selected studies, extracted data and assessed the risk of bias in included trials. We conducted random-effects meta-analyses were appropriate.
MAIN RESULTS
Earlier versions of this review were published in 2016 and 2019. In this update, we included 24 studies with 2278 participants, of which 14 were randomised controlled trials (RCT), one was a quasi-RCT and nine had a non-randomised design. Eight studies compared types of PPE. Six studies evaluated adapted PPE. Eight studies compared donning and doffing processes and three studies evaluated types of training. Eighteen studies used simulated exposure with fluorescent markers or harmless microbes. In simulation studies, median contamination rates were 25% for the intervention and 67% for the control groups. Evidence for all outcomes is of very low certainty unless otherwise stated because it is based on one or two studies, the indirectness of the evidence in simulation studies and because of risk of bias. Types of PPE The use of a powered, air-purifying respirator with coverall may protect against the risk of contamination better than a N95 mask and gown (risk ratio (RR) 0.27, 95% confidence interval (CI) 0.17 to 0.43) but was more difficult to don (non-compliance: RR 7.5, 95% CI 1.81 to 31.1). In one RCT (59 participants), people with a long gown had less contamination than those with a coverall, and coveralls were more difficult to doff (low-certainty evidence). Gowns may protect better against contamination than aprons (small patches: mean difference (MD) -10.28, 95% CI -14.77 to -5.79). PPE made of more breathable material may lead to a similar number of spots on the trunk (MD 1.60, 95% CI -0.15 to 3.35) compared to more water-repellent material but may have greater user satisfaction (MD -0.46, 95% CI -0.84 to -0.08, scale of 1 to 5). Modified PPE versus standard PPE The following modifications to PPE design may lead to less contamination compared to standard PPE: sealed gown and glove combination (RR 0.27, 95% CI 0.09 to 0.78), a better fitting gown around the neck, wrists and hands (RR 0.08, 95% CI 0.01 to 0.55), a better cover of the gown-wrist interface (RR 0.45, 95% CI 0.26 to 0.78, low-certainty evidence), added tabs to grab to facilitate doffing of masks (RR 0.33, 95% CI 0.14 to 0.80) or gloves (RR 0.22, 95% CI 0.15 to 0.31). Donning and doffing Using Centers for Disease Control and Prevention (CDC) recommendations for doffing may lead to less contamination compared to no guidance (small patches: MD -5.44, 95% CI -7.43 to -3.45). One-step removal of gloves and gown may lead to less bacterial contamination (RR 0.20, 95% CI 0.05 to 0.77) but not to less fluorescent contamination (RR 0.98, 95% CI 0.75 to 1.28) than separate removal. Double-gloving may lead to less viral or bacterial contamination compared to single gloving (RR 0.34, 95% CI 0.17 to 0.66) but not to less fluorescent contamination (RR 0.98, 95% CI 0.75 to 1.28). Additional spoken instruction may lead to fewer errors in doffing (MD -0.9, 95% CI -1.4 to -0.4) and to fewer contamination spots (MD -5, 95% CI -8.08 to -1.92). Extra sanitation of gloves before doffing with quaternary ammonium or bleach may decrease contamination, but not alcohol-based hand rub. Training The use of additional computer simulation may lead to fewer errors in doffing (MD -1.2, 95% CI -1.6 to -0.7). A video lecture on donning PPE may lead to better skills scores (MD 30.70, 95% CI 20.14 to 41.26) than a traditional lecture. Face-to-face instruction may reduce noncompliance with doffing guidance more (odds ratio 0.45, 95% CI 0.21 to 0.98) than providing folders or videos only.
AUTHORS' CONCLUSIONS
We found low- to very low-certainty evidence that covering more parts of the body leads to better protection but usually comes at the cost of more difficult donning or doffing and less user comfort, and may therefore even lead to more contamination. More breathable types of PPE may lead to similar contamination but may have greater user satisfaction. Modifications to PPE design, such as tabs to grab, may decrease the risk of contamination. For donning and doffing procedures, following CDC doffing guidance, a one-step glove and gown removal, double-gloving, spoken instructions during doffing, and using glove disinfection may reduce contamination and increase compliance. Face-to-face training in PPE use may reduce errors more than folder-based training. We still need RCTs of training with long-term follow-up. We need simulation studies with more participants to find out which combinations of PPE and which doffing procedure protects best. Consensus on simulation of exposure and assessment of outcome is urgently needed. We also need more real-life evidence. Therefore, the use of PPE of HCW exposed to highly infectious diseases should be registered and the HCW should be prospectively followed for their risk of infection.
Topics: Betacoronavirus; Body Fluids; COVID-19; Computer Simulation; Coronavirus Infections; Health Personnel; Hemorrhagic Fever, Ebola; Humans; Infectious Disease Transmission, Patient-to-Professional; Pandemics; Personal Protective Equipment; Pneumonia, Viral; Randomized Controlled Trials as Topic; Respiratory Protective Devices; SARS-CoV-2; Severe Acute Respiratory Syndrome
PubMed: 32293717
DOI: 10.1002/14651858.CD011621.pub4 -
The Cochrane Database of Systematic... Mar 2021High-flow nasal cannulae (HFNC) deliver high flows of blended humidified air and oxygen via wide-bore nasal cannulae and may be useful in providing respiratory support... (Meta-Analysis)
Meta-Analysis
BACKGROUND
High-flow nasal cannulae (HFNC) deliver high flows of blended humidified air and oxygen via wide-bore nasal cannulae and may be useful in providing respiratory support for adults experiencing acute respiratory failure, or at risk of acute respiratory failure, in the intensive care unit (ICU). This is an update of an earlier version of the review.
OBJECTIVES
To assess the effectiveness of HFNC compared to standard oxygen therapy, or non-invasive ventilation (NIV) or non-invasive positive pressure ventilation (NIPPV), for respiratory support in adults in the ICU.
SEARCH METHODS
We searched CENTRAL, MEDLINE, Embase, CINAHL, Web of Science, and the Cochrane COVID-19 Register (17 April 2020), clinical trial registers (6 April 2020) and conducted forward and backward citation searches.
SELECTION CRITERIA
We included randomized controlled studies (RCTs) with a parallel-group or cross-over design comparing HFNC use versus other types of non-invasive respiratory support (standard oxygen therapy via nasal cannulae or mask; or NIV or NIPPV which included continuous positive airway pressure and bilevel positive airway pressure) in adults admitted to the ICU.
DATA COLLECTION AND ANALYSIS
We used standard methodological procedures as expected by Cochrane.
MAIN RESULTS
We included 31 studies (22 parallel-group and nine cross-over designs) with 5136 participants; this update included 20 new studies. Twenty-one studies compared HFNC with standard oxygen therapy, and 13 compared HFNC with NIV or NIPPV; three studies included both comparisons. We found 51 ongoing studies (estimated 12,807 participants), and 19 studies awaiting classification for which we could not ascertain study eligibility information. In 18 studies, treatment was initiated after extubation. In the remaining studies, participants were not previously mechanically ventilated. HFNC versus standard oxygen therapy HFNC may lead to less treatment failure as indicated by escalation to alternative types of oxygen therapy (risk ratio (RR) 0.62, 95% confidence interval (CI) 0.45 to 0.86; 15 studies, 3044 participants; low-certainty evidence). HFNC probably makes little or no difference in mortality when compared with standard oxygen therapy (RR 0.96, 95% CI 0.82 to 1.11; 11 studies, 2673 participants; moderate-certainty evidence). HFNC probably results in little or no difference to cases of pneumonia (RR 0.72, 95% CI 0.48 to 1.09; 4 studies, 1057 participants; moderate-certainty evidence), and we were uncertain of its effect on nasal mucosa or skin trauma (RR 3.66, 95% CI 0.43 to 31.48; 2 studies, 617 participants; very low-certainty evidence). We found low-certainty evidence that HFNC may make little or no difference to the length of ICU stay according to the type of respiratory support used (MD 0.12 days, 95% CI -0.03 to 0.27; 7 studies, 1014 participants). We are uncertain whether HFNC made any difference to the ratio of partial pressure of arterial oxygen to the fraction of inspired oxygen (PaO/FiO) within 24 hours of treatment (MD 10.34 mmHg, 95% CI -17.31 to 38; 5 studies, 600 participants; very low-certainty evidence). We are uncertain whether HFNC made any difference to short-term comfort (MD 0.31, 95% CI -0.60 to 1.22; 4 studies, 662 participants, very low-certainty evidence), or to long-term comfort (MD 0.59, 95% CI -2.29 to 3.47; 2 studies, 445 participants, very low-certainty evidence). HFNC versus NIV or NIPPV We found no evidence of a difference between groups in treatment failure when HFNC were used post-extubation or without prior use of mechanical ventilation (RR 0.98, 95% CI 0.78 to 1.22; 5 studies, 1758 participants; low-certainty evidence), or in-hospital mortality (RR 0.92, 95% CI 0.64 to 1.31; 5 studies, 1758 participants; low-certainty evidence). We are very uncertain about the effect of using HFNC on incidence of pneumonia (RR 0.51, 95% CI 0.17 to 1.52; 3 studies, 1750 participants; very low-certainty evidence), and HFNC may result in little or no difference to barotrauma (RR 1.15, 95% CI 0.42 to 3.14; 1 study, 830 participants; low-certainty evidence). HFNC may make little or no difference to the length of ICU stay (MD -0.72 days, 95% CI -2.85 to 1.42; 2 studies, 246 participants; low-certainty evidence). The ratio of PaO/FiO may be lower up to 24 hours with HFNC use (MD -58.10 mmHg, 95% CI -71.68 to -44.51; 3 studies, 1086 participants; low-certainty evidence). We are uncertain whether HFNC improved short-term comfort when measured using comfort scores (MD 1.33, 95% CI 0.74 to 1.92; 2 studies, 258 participants) and responses to questionnaires (RR 1.30, 95% CI 1.10 to 1.53; 1 study, 168 participants); evidence for short-term comfort was very low certainty. No studies reported on nasal mucosa or skin trauma.
AUTHORS' CONCLUSIONS
HFNC may lead to less treatment failure when compared to standard oxygen therapy, but probably makes little or no difference to treatment failure when compared to NIV or NIPPV. For most other review outcomes, we found no evidence of a difference in effect. However, the evidence was often of low or very low certainty. We found a large number of ongoing studies; including these in future updates could increase the certainty or may alter the direction of these effects.
Topics: Acute Disease; Adult; Barotrauma; Bias; Critical Care; Hospital Mortality; Humans; Intubation; Length of Stay; Masks; Nasal Mucosa; Noninvasive Ventilation; Oxygen Inhalation Therapy; Patient Reported Outcome Measures; Pneumonia; Randomized Controlled Trials as Topic; Respiration, Artificial; Respiratory Insufficiency; Treatment Failure
PubMed: 33661521
DOI: 10.1002/14651858.CD010172.pub3 -
Anaesthesia Oct 2014We systematically reviewed 31 adult randomised clinical trials of the i-gel(®) vs laryngeal mask airway. The mean (95% CI) leak pressure difference and relative risk... (Comparative Study)
Comparative Study Meta-Analysis Review
We systematically reviewed 31 adult randomised clinical trials of the i-gel(®) vs laryngeal mask airway. The mean (95% CI) leak pressure difference and relative risk (95% CI) of insertion on the first attempt were similar: 0.40 (-1.23 to 2.02) cmH2 O and 0.98 (0.95-1.01), respectively. The mean (95% CI) insertion time and the relative risk (95% CI) of sore throat were less with the i-gel: by 1.46 (0.33-2.60) s, p = 0.01, and 0.59 (0.38-0.90), p = 0.02, respectively. The relative risk of poor fibreoptic view through the i-gel was 0.29 (0.16-0.54), p < 0.0001. All outcomes displayed substantial heterogeneity, I(2) ≥ 75%. Subgroup analyses did not decrease heterogeneity, but suggested that insertion of the i-gel was faster than for first-generation laryngeal mask airways and that the i-gel leak pressure was higher than first generation, but lower than second-generation, laryngeal mask airways. A less frequent sore throat was the main clinical advantage of the i-gel.
Topics: Adult; Humans; Laryngeal Masks; Pharyngitis; Randomized Controlled Trials as Topic
PubMed: 25040063
DOI: 10.1111/anae.12772 -
International Journal of Environmental... Jan 2023Masks are essential and effective small protective devices used to protect the general public against infections such as COVID-19. However, available systematic reviews... (Review)
Review
Masks are essential and effective small protective devices used to protect the general public against infections such as COVID-19. However, available systematic reviews and summaries on the filtration performance of masks are lacking. Therefore, in order to investigate the filtration performance of masks, filtration mechanisms, mask characteristics, and the relationships between influencing factors and protective performance were first analyzed through mask evaluations. The summary of filtration mechanisms and mask characteristics provides readers with a clear and easy-to-understand theoretical cognition. Then, a detailed analysis of influencing factors and the relationships between the influencing factors and filtration performance is presented in. The influence of the aerosol size and type on filtration performance is nonlinear and nonconstant, and filtration efficiency decreases with an increase in the gas flow rate; moreover, fitness plays a decisive role in the protective effects of masks. It is recommended that the public should wear surgical masks to prevent COVID-19 infection in low-risk and non-densely populated areas. Future research should focus on fitness tests, and the formulation of standards should also be accelerated. This paper provides a systematic review that will be helpful for the design of masks and public health in the future.
Topics: Humans; COVID-19; Masks; SARS-CoV-2; Respiratory Aerosols and Droplets; Filtration; Respiratory Protective Devices; Personal Protective Equipment
PubMed: 36767714
DOI: 10.3390/ijerph20032346 -
Journal of the American College of... Feb 2023
Comments on Collins et al "N95 respirator and surgical mask effectiveness against respiratory viral illnesses in the healthcare setting: A systematic review and meta-analysis".
PubMed: 36776214
DOI: 10.1002/emp2.12893 -
Journal of Otolaryngology - Head & Neck... 2024Adenotonsillectomy is one of the most common surgical procedures worldwide. The current standard for securing the airway in patients undergoing adenotonsillectomy is... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Adenotonsillectomy is one of the most common surgical procedures worldwide. The current standard for securing the airway in patients undergoing adenotonsillectomy is endotracheal tube (ETT) intubation. Several studies have investigated the use of the laryngeal mask airway (LMA) in this procedure. We conducted a systematic review and meta-analysis to compare the safety and efficacy of the LMA versus ETT in adenotonsillectomy.
METHOD
Databases were searched from inception to 2022 for randomized controlled trials and comparative studies. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. The primary outcome is the rate of perioperative respiratory adverse events (PRAEs). Secondary outcomes included the rate of conversion to ETT, desaturations, nausea/vomiting, and surgical time. A subgroup analysis, risk of bias, publication bias, and Grading of Recommendations Assessment, Development, and Evaluation (GRADE) assessments were also performed.
RESULTS
Twelve studies were included in the analysis (4176 patients). The mean overall conversion to ETT was 8.36% [95% confidence interval (CI) = 8.17, 8.54], and for the pediatric group 8.27% (95% CI = 8.08, 8.47). The mean rate of conversion to ETT secondary to complications was 2.89% (95% CI = 2.76, 3.03) while the rest was from poor surgical access. Overall, there was no significant difference in PRAEs [odds ratio (OR) 1.16, 95% CI = 0.60, 2.22], desaturations (OR 0.79, 95% CI = 0.38, 1.64), or minor complications (OR 0.89, 95% CI = 0.50, 1.55). The use of LMA yielded significantly shorter operative time (mean difference -4.38 minutes, 95% CI = -8.28, -0.49) and emergence time (mean difference -4.15 minutes, 95% CI = -5.63, -2.67).
CONCLUSION
For adenotonsillectomy surgery, LMA is a safe alternative to ETT and requires less operative time. Careful patient selection and judgment of the surgeon and anesthesiologist are necessary, especially given the 8% conversion to ETT rate.
Topics: Humans; Tonsillectomy; Adenoidectomy; Laryngeal Masks; Intubation, Intratracheal; Postoperative Complications
PubMed: 38899617
DOI: 10.1177/19160216241263851 -
Preventive Medicine Reports Dec 2023Former -analyses concluded that there was not sufficient evidence to determine the effect of surgical masks and N95 respirators. We collected randomized controlled... (Review)
Review
Former -analyses concluded that there was not sufficient evidence to determine the effect of surgical masks and N95 respirators. We collected randomized controlled trials (RCTs) and conducted a systematic review and -analysis to evaluate the efficacy of N95 respirators and surgical masks for protection against COVID-19. We retrieved relevant RCTs published between January 2019 and January 2023 by searching the PubMed, EMBASE, and Cochrane CENTRAL. Study quality was evaluated using the Cochrane Risk of Bias tool with the RevMan 5.4 software. Meta-analyses were conducted to calculate pooled estimates using the RevMan 5.4 software. A total of six RCTs were finally included. The findings revealed that wearing a mark made little difference in preventing COVID-19 [odds ratio (OR) = 0.10; 95% confidence interval (CI): 0.01-0.93; = 0.04]. Subgroup analysis showed that the heterogeneity of data was I = 64% (OR = 0.32; 95% CI: 0.06-1.77; = 0.19) for surgical mask use and I = 0% (OR = 0.03; 95 %CI: 0.01-0.15; < 0.01) for N95 respirator use. The heterogeneity of data for medical staff was I = 0% (OR = 0.03; 95 %CI: 0.01-0.12; < 0.01). Meta-analysis indicated a protective effect of N95 respirators against COVID-19, particularly for medical staff. The use of surgical masks is not associated with a lower risk of COVID-19. However, the subgroup using N95 respirators, particularly medical staff, showed a significant protective. These findings suggest that N95 respirators should be reserved for high-risk medical staff in the absence of sufficient resources during an epidemic. But the number of included studies was small, more studies in future analyses is required to reduce the risk of distribution bias.
PubMed: 37736310
DOI: 10.1016/j.pmedr.2023.102414 -
Annals of Palliative Medicine Nov 2021Difficulty in mask ventilation is one of the more dangerous factors in general anesthesia. The traditional mask has some problems, such as air leakage and facial skin... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Difficulty in mask ventilation is one of the more dangerous factors in general anesthesia. The traditional mask has some problems, such as air leakage and facial skin compression injury. The head cover is a new interactive non-invasive ventilation (NIV) model. NIV studies comparing hoods and masks have all been single-center and small-sample randomized trials, and extensive clinical studies are lacking.
METHODS
We conducted a computerized search in the databases of PubMed, Embase, Medline, Chinese Biomedical Literature (CBM), and others for randomized controlled trials (RCTs) on the effect of hoods and masks on patients with respiratory failure published since their establishment to March 2021. The quality of the included literature was assessed using the Cochrane Systematic Review Manual, and the data was analyzed using Review Manager 5.3 to assess the risk of bias.
RESULTS
A total of 9 articles were included, involving 462 patients, with 233 patients in the hood group and 229 patients in the face mask group. The results of meta-analysis showed the comparative endotracheal intubation rate of the hood group and the mask group [odds ratio (OR) =0.26; 95% confidence interval (CI): 0.14 to 0.47; Z=4.48; P<0.00001], the complications rate (OR =0.54; 95% CI: 0.31 to 0.97; Z=2.08; P=0.04) was statistically considerable, although there was no considerable difference in in-hospital mortality (OR =0.56; 95% CI: 0.28 to 1.14; Z=1.59; P=0.11).
DISCUSSION
NIV with a hood can reduce the rate of endotracheal intubation and the incidence of related complications in patients with acute respiratory failure (ARF), which has considerable advantages in contrast to the traditional mask.
Topics: Anesthesia, General; Humans; Noninvasive Ventilation; Respiration, Artificial; Respiratory Distress Syndrome; Respiratory Insufficiency
PubMed: 34872284
DOI: 10.21037/apm-21-2709 -
Philosophical Transactions. Series A,... Oct 2023This rapid systematic review of evidence asks whether (i) wearing a face mask, (ii) one type of mask over another and (iii) mandatory mask policies can reduce the... (Review)
Review
This rapid systematic review of evidence asks whether (i) wearing a face mask, (ii) one type of mask over another and (iii) mandatory mask policies can reduce the transmission of SARS-CoV-2 infection, either in community-based or healthcare settings. A search of studies published 1 January 2020-27 January 2023 yielded 5185 unique records. Due to a paucity of randomized controlled trials (RCTs), observational studies were included in the analysis. We analysed 35 studies in community settings (three RCTs and 32 observational) and 40 in healthcare settings (one RCT and 39 observational). Ninety-five per cent of studies included were conducted before highly transmissible Omicron variants emerged. Ninety-one per cent of observational studies were at 'critical' risk of bias (ROB) in at least one domain, often failing to separate the effects of masks from concurrent interventions. More studies found that masks ( = 39/47; 83%) and mask mandates ( = 16/18; 89%) reduced infection than found no effect ( = 8/65; 12%) or favoured controls ( = 1/65; 2%). Seven observational studies found that respirators were more protective than surgical masks, while five found no statistically significant difference between the two mask types. Despite the ROB, and allowing for uncertain and variable efficacy, we conclude that wearing masks, wearing higher quality masks (respirators), and mask mandates generally reduced SARS-CoV-2 transmission in these study populations. This article is part of the theme issue 'The effectiveness of non-pharmaceutical interventions on the COVID-19 pandemic: the evidence'.
Topics: Humans; COVID-19; Masks; Policy; SARS-CoV-2
PubMed: 37611625
DOI: 10.1098/rsta.2023.0133 -
Anesthesiology Research and Practice 2020Use of laryngeal mask airway as an alternative to the endotracheal tube has attracted the attention of several workers with regard to intraocular pressure changes.... (Review)
Review
BACKGROUND
Use of laryngeal mask airway as an alternative to the endotracheal tube has attracted the attention of several workers with regard to intraocular pressure changes. However, the previous studies have reported different results while comparing intraocular pressure, following insertion of laryngeal mask airway or the endotracheal tube. Therefore, this systematic review and meta-analysis was aimed to generate the best possible evidence on the intraocular pressure response to endotracheal tube intubation and laryngeal mask airway insertion.
METHODS
Electronic databases like PubMed, CINAHL, EMBASE, Google Scholar, Cochrane library databases, and Mednar were used. All original peer-reviewed papers which reported the mean and standard deviation of IOP before and after airway instrumentation in both groups were included. Two reviewers independently extracted the data using a standardized data extraction format for eligibility and appraised their quality. Data were analyzed using the STATA version 14 software. The pooled standard mean difference was estimated with the random-effect model. Heterogeneity between studies was assessed by the statistics test. A subgroup analysis was done to assess the source of variation between the studies.
RESULT
A total of 47 research papers were reviewed, of which, six studies were finally included in this systematic review and meta-analysis. The overall pooled standard mean difference of intraocular pressure was 1.30 (95% CI, 0.70, 1.90), showing that LMA insertion is better than ETT intubation to maintain stable intraocular pressure. A random-effect model was employed to estimate the pooled standard mean differences due to severe heterogeneity ( 79.45, ≤ 0.001).
CONCLUSION
The available information suggests that the LMA provides lesser intraocular pressure response in comparison with the conventional tracheal tube.
PubMed: 32695160
DOI: 10.1155/2020/7858434