Tracheal tube cuff pressure during anesthesia for robotic-assisted laparoscopic prostatectomy and the efficacy of an automatic cuff pressure controller (SmartCuff): observational studies of 1-sample paired data.

PURPOSE: The cuff pressure of a tracheal tube may increase during robot-assisted laparoscopic surgery for prostatectomy (RALP), which requires pneumoperitoneum in a steep head-down position, but there have been no studies which confirmed this. METHODS: In study 1, we studied how frequently the cuff pressure significantly increased during anesthesia for the RALP. In study 2, we studied if the SmartCuff (Smiths Medical Japan, Tokyo) automatic cuff pressure controller would minimize the changes in the intracuff pressure. With approval of the study by the research ethics committee (approved number: 20115), we measured the cuff pressures in anesthetized patients undergoing RALP and in those undergoing gynecological laparotomy (as a reference cohort), with and without the use of the SmartCuff. RESULTS: In 21 patients undergoing RALP, a clinically meaningful increase (5 cmH2O or greater) was observed in all the 21 patients (P = 0.00; 95% CI for difference: 86-100%), whereas in 23 patients undergoing gynecological laparotomy, a clinically meaningful decrease (5 cmH2O or greater) was observed in 21 of 23 patients (91%, P < 0.0001; 95% CI for difference: 72-99%). With the use of the SmartCuff, there was no significant increase in the incidence of a clinically meaningful change in the intracuff pressure in either cohort. CONCLUSION: The cuff pressure of a tracheal tube would frequently increase markedly in patients undergoing RALP, whereas it would frequently decrease markedly in patients undergoing gynecological laparotomy. The SmartCuff may inhibit the changes in the cuff pressure during anesthesia.

The Role of Traffic Volume on Sound Pressure Level Reduction before and during COVID-19 Lockdown Measures-A Case Study in Bochum, Germany.

During the SARS-CoV-2 pandemic, sound pressure levels (SPL) decreased because of lockdown measures all over the world. This study aims to describe SPL changes over varying lockdown measure timeframes and estimate the role of traffic on SPL variations. To account for different COVID-19 lockdown measures, the timeframe during the pandemic was segmented into four phases. To analyze the association between a-weighted decibels (dB(A)) and lockdown phases relative to the pre-lockdown timeframe, we calculated a linear mixed model, using 36,710 h of recording time. Regression coefficients depicting SPL changes were compared, while the model was subsequently adjusted for wind speed, rainfall, and traffic volume. The relative adjusted reduction of during pandemic phases to pre-pandemic levels ranged from -0.99 dB(A) (CI: -1.45; -0.53) to -0.25 dB(A) (CI: -0.96; 0.46). After controlling for traffic volume, we observed little to no reduction (-0.16 dB(A) (CI: -0.77; 0.45)) and even an increase of 0.75 dB(A) (CI: 0.18; 1.31) during the different lockdown phases. These results showcase the major role of traffic regarding the observed reduction. The findings can be useful in assessing measures to decrease noise pollution for necessary future population-based prevention.

Impact of wearing a surgical and cloth mask during cycle exercise.

We sought to determine the impact of wearing cloth or surgical masks on the cardiopulmonary responses to moderate-intensity exercise. Twelve subjects (n = 5 females) completed three, 8-min cycling trials while breathing through a non-rebreathing valve (laboratory control), cloth, or surgical mask. Heart rate (HR), oxyhemoglobin saturation (SpO2), breathing frequency, mouth pressure, partial pressure of end-tidal carbon dioxide (PetCO2) and oxygen (PetO2), dyspnea were measured throughout exercise. A subset of n = 6 subjects completed an additional exercise bout without a mask (ecological control). There were no differences in breathing frequency, HR or SpO2 across conditions (all p > 0.05). Compared with the laboratory control (4.7 ± 0.9 cmH2O [mean ± SD]), mouth pressure swings were smaller with the surgical mask (0.9 ± 0.7; p < 0.0001), but similar with the cloth mask (3.6 ± 4.8 cmH2O; p = 0.66). Wearing a cloth mask decreased PetO2 (-3.5 ± 3.7 mm Hg) and increased PetCO2 (+2.0 ± 1.3 mm Hg) relative to the ecological control (both p < 0.05). There were no differences in end-tidal gases between mask conditions and laboratory control (both p > 0.05). Dyspnea was similar between the control conditions and the surgical mask (p > 0.05) but was greater with the cloth mask compared with laboratory (+0.9 ± 1.2) and ecological (+1.5 ± 1.3) control conditions (both p < 0.05). Wearing a mask during short-term moderate-intensity exercise may increase dyspnea but has minimal impact on the cardiopulmonary response. Novelty: Wearing surgical or cloth masks during exercise has no impact on breathing frequency, tidal volume, oxygenation, and heart rate However, there are some changes in inspired and expired gas fractions that are physiologically irrelevant. In young healthy individuals, wearing surgical or cloth masks during submaximal exercise has few physiological consequences.

Effect of Oral Health Education Using a Mobile App (OHEMA) on the Oral Health and Swallowing-Related Quality of Life in Community-Based Integrated Care of the Elderly: A Randomized Clinical Trial.

This study investigated the effect of oral health education using a mobile app (OHEMA) on the oral health and swallowing-related quality of life (SWAL-QoL) of the elderly population in a community-based integrated care project (CICP). Forty elderly individuals in the CICP were randomized into intervention and control groups. OHEMA provided information on customized oral health care management, oral exercises, and intraoral and extraoral massage methods for 50 min/session, once a week, for 6 weeks. Pre- and post-intervention surveys assessed the unstimulated salivary flow rate, subjective oral dryness, tongue pressure, and SWAL-QoL, which were analyzed using ANCOVA and repeated measures ANOVA. In the intervention group, tongue pressure increased significantly from pre- (17.75) to post-intervention (27.24) (p < 0.001), and subjective oral dryness decreased from pre- (30.75) to post-intervention (18.50). The unstimulated salivary flow rate had a higher mean score in the intervention group (7.19) than in the control group (5.04) (p < 0.001). The SWAL-QoL significantly improved from pre- (152.10) to post-intervention (171.50) in the intervention group (p < 0.001) but did not change significantly in the control group (p > 0.05). OHEMA appears to be a useful tool for oral health education for the elderly as it improved the SWAL-QoL, with increased tongue pressure and reduced oral dryness.

Improving lung compliance by external compression of the chest wall.

As exemplified by prone positioning, regional variations of lung and chest wall properties provide possibilities for modifying transpulmonary pressures and suggest that clinical interventions related to the judicious application of external pressure may yield benefit. Recent observations made in late-phase patients with severe ARDS caused by COVID-19 (C-ARDS) have revealed unexpected mechanical responses to local chest wall compressions over the sternum and abdomen in the supine position that challenge the clinician's assumptions and conventional bedside approaches to lung protection. These findings appear to open avenues for mechanism-defining research investigation with possible therapeutic implications for all forms and stages of ARDS.

Pressure Injuries Due to Personal Protective Equipment in COVID-19 Critical Care Units.

BACKGROUND: Caring for patients with COVID-19 requires wearing a full set of personal protective equipment (PPE) to avoid contamination. Personal discomfort has been associated with use of PPE, and anecdotal reports describe pressure injuries related to wearing PPE. OBJECTIVES: To investigate the occurrence of device-related pressure injuries due to wearing PPE among Italian nurses caring for patients with COVID-19 in critical care settings. METHODS: This descriptive study used an online survey investigating both the demographic characteristics of respondents and complications related to wearing PPE, including the development of pressure injuries. RESULTS: A total of 266 nurses throughout Italy completed the survey; 32% of respondents were men. Nurses' median age was 36 years (range 22-59 years), and the median time spent working in their current clinical setting (an intensive care or high-dependency unit) was 3 years (range 0-32 years). Personal protective equipment was worn for a median duration of 5 hours (range 2-12 hours). While wearing PPE, 92.8% of nurses experienced pain and 77.1% developed device-related pressure injuries, mainly on the nose, ears, and forehead. Pain was more frequent among nurses with such injuries. Transparent dressings, emollient cream, and no dressing were associated with development of device-related pressure injury. CONCLUSIONS: Pressure injuries related to PPE represent an important adverse effect for nurses caring for patients with COVID-19. This topic deserves study to determine adequate solutions for preventing and treating such injuries and their potential influence on nurses' work tolerance.

[Peripheral facial paralysis in patients with SARS-CoV-2 in prono position]. / Parálisis facial periférica en pacientes con SARS-CoV-2 en decúbito prono.

TITLE: Parálisis facial periférica en pacientes con SARS-CoV-2 en decúbito prono.

Airflow dispersion during common neonatal resuscitation procedures: A simulation study.

BACKGROUND: Aerosol generating medical procedures (AGMPs) are common during newborn resuscitation. Neonates with respiratory viruses such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection may pose a risk to healthcare workers. International guidelines differ on methods to minimize the risk due to limited data. OBJECTIVE: We examined the expiratory airflow dispersion during common neonatal resuscitation AGMPs using infant simulators. METHODS: Expiratory airflow dispersion in term and preterm manikins was simulated (n = 288) using fine particle smoke at tidal volumes of 5 ml/kg. Using ImageJ, we quantified dispersion during common airway procedures including endotracheal tube (ETT) and T-piece ventilation. RESULTS: Maximal expiratory dispersion distances for the unsupported airway and disconnected uncuffed ETT scenarios were 30.2 and 22.7 cm (term); 22.1 and 17.2 cm (preterm), respectively. Applying T-piece positive end expiratory pressure (PEEP) via an ETT (ETTPEEP ) generated no expiratory dispersion but increased tube leak during term simulation, while ventilation breaths (ETTVENT ) caused significant expiratory dispersion and leak. There was no measurable dispersion during face mask ventilation. For term uncuffed ETT ventilation, the particle filter eliminated expiratory dispersion but increased leak. No expiratory dispersion and negligible leak were observed when combining a cuffed ETT and filter. Angulated T-pieces generated the greatest median dispersion distances of 35.8 cm (ETTPEEP ) and 23.3 cm (ETTVENT ). CONCLUSIONS: Airflow dispersion during neonatal AGMPs is greater than previously postulated and potentially could contaminate healthcare providers during resuscitation of infants infected with contagious viruses such as SARS-CoV-2. It is possible to mitigate this risk using particle filters and cuffed ETTs. Applicability in the clinical setting requires further evaluation.

Ca2+-dependent mechanism of membrane insertion and destabilization by the SARS-CoV-2 fusion peptide.

Cell penetration after recognition of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus by the ACE2 receptor and the fusion of its viral envelope membrane with cellular membranes are the early steps of infectivity. A region of the Spike protein of the virus, identified as the "fusion peptide" (FP), is liberated at its N-terminal site by a specific cleavage occurring in concert with the interaction of the receptor-binding domain of the Spike. Studies have shown that penetration is enhanced by the required binding of Ca2+ ions to the FPs of coronaviruses, but the mechanisms of membrane insertion and destabilization remain unclear. We have predicted the preferred positions of Ca2+ binding to the SARS-CoV-2-FP, the role of Ca2+ ions in mediating peptide-membrane interactions, the preferred mode of insertion of the Ca2+-bound SARS-CoV-2-FP, and consequent effects on the lipid bilayer from extensive atomistic molecular dynamics simulations and trajectory analyses. In a systematic sampling of the interactions of the Ca2+-bound peptide models with lipid membranes, SARS-CoV-2-FP penetrated the bilayer and disrupted its organization only in two modes involving different structural domains. In one, the hydrophobic residues F833/I834 from the middle region of the peptide are inserted. In the other, more prevalent mode, the penetration involves residues L822/F823 from the LLF motif, which is conserved in CoV-2-like viruses, and is achieved by the binding of Ca2+ ions to the D830/D839 and E819/D820 residue pairs. FP penetration is shown to modify the molecular organization in specific areas of the bilayer, and the extent of membrane binding of the SARS-CoV-2 FP is significantly reduced in the absence of Ca2+ ions. These findings provide novel mechanistic insights regarding the role of Ca2+ in mediating SARS-CoV-2 fusion and provide a detailed structural platform to aid the ongoing efforts in rational design of compounds to inhibit SARS-CoV-2 cell entry.

Proposal of selective wedge instillation of pulmonary surfactant for COVID-19 pneumonia based on computational fluid dynamics simulation.

BACKGROUND: The most important target cell of SARS-CoV-2 is Type II pneumocyte which produces and secretes pulmonary surfactant (PS) that prevents alveolar collapse. PS instillation therapy is dramatically effective for infant respiratory distress syndrome but has been clinically ineffective for ARDS. Nowadays, ARDS is regarded as non-cardiogenic pulmonary edema with vascular hyper-permeability regardless of direct relation to PS dysfunction. However, there is a possibility that this ineffectiveness of PS instillation for ARDS is caused by insufficient delivery. Then, we performed PS instillation simulation with realistic human airway models by the use of computational fluid dynamics, and investigated how instilled PS would move in the liquid layer covering the airway wall and reach to alveolar regions. METHODS: Two types of 3D human airway models were prepared: one was from the trachea to the lobular bronchi and the other was from a subsegmental bronchus to respiratory bronchioles. The thickness of the liquid layer covering the airway was assigned as 14 % of the inner radius of the airway segment. The liquid layer was assumed to be replaced by an instilled PS. The flow rate of the instilled PS was assigned a constant value, which was determined by the total amount and instillation time in clinical use. The PS concentration of the liquid layer during instillation was computed by solving the advective-diffusion equation. RESULTS: The driving pressure from the trachea to respiratory bronchioles was calculated at 317 cmH2O, which is about 20 times of a standard value in conventional PS instillation method where the driving pressure was given by difference between inspiratory and end-expiratory pressures of a ventilator. It means that almost all PS does not reach the alveolar regions but moves to and fro within the airway according to the change in ventilator pressure. The driving pressure from subsegmental bronchus was calculated at 273 cm H2O, that is clinically possible by wedge instillation under bronchoscopic observation. CONCLUSIONS: The simulation study has revealed that selective wedge instillation under bronchoscopic observation should be tried for COVID-19 pneumonia before the onset of ARDS. It will be also useful for preventing secondary lung fibrosis.

Association between N95 respirator wearing and device-related pressure injury in the fight against COVID-19: a multicentre cross-sectional survey in China.

OBJECTIVES: To explore the association between N95 respirator wearing and device-related pressure injury (DRPI) and to provide a basis for protecting medical staff from skin injuries. DESIGN: A cross-sectional, multicentre study. SETTING AND PARTICIPANTS: Medical staff of 60 hospitals were selected from 145 designated medical institutions located in the epidemic area where the patients with COVID-19 were treated in China. RESULTS: In total, 1761 respondents wore N95 respirators (use alone 20.8%; combination use 79.2%), and the prevalence of DRPI was 59.2% (95% CI 56.93 to 61.53). A daily wearing time of >4 hours (OR 1.62, 95% CI 1.11 to 2.35), wearing a N95 respirator in combination with goggles both with the presence of sweating (OR 13.40, 95% CI 7.34 to 23.16) and without the presence of sweating (OR 0.80, 95% CI 0.56 to 1.14) and wearing only a N95 respirator with the presence of sweating (OR 9.60, 95% CI 7.00 to 13.16) were associated with DRPI. A correspondence analysis indicated that if there was no sweating, regardless of whether the N95 respirator was worn by itself or in combination with goggles, single-site DRPI mainly occurred on the nose bridge, cheek and auricle. If there was sweating present, regardless of whether the N95 was worn by itself or in combination with goggles, multiple DRPI sites occurred more often on the face. CONCLUSIONS: The prevalence of DRPI among medical staff caused by N95 respirators was very high, which was mainly associated with a longer daily wearing time and interaction with sweating. The nasal bridge, cheeks and auricles were the primary protection locations found.

Delivery system can vary ventilatory parameters across multiple patients from a single source of mechanical ventilation.

BACKGROUND: Current limitations in the supply of ventilators during the Covid19 pandemic have limited respiratory support for patients with respiratory failure. Split ventilation allows a single ventilator to be used for more than one patient but is not practicable due to requirements for matched patient settings, risks of cross-contamination, harmful interference between patients and the inability to individualize ventilator support parameters. We hypothesized that a system could be developed to circumvent these limitations. METHODS AND FINDINGS: A novel delivery system was developed to allow individualized peak inspiratory pressure settings and PEEP using a pressure regulatory valve, developed de novo, and an inline PEEP 'booster'. One-way valves, filters, monitoring ports and wye splitters were assembled in-line to complete the system and achieve the design targets. This system was then tested to see if previously described limitations could be addressed. The system was investigated in mechanical and animal trials (ultimately with a pig and sheep concurrently ventilated from the same ventilator). The system demonstrated the ability to provide ventilation across clinically relevant scenarios including circuit occlusion, unmatched physiology, and a surgical procedure, while allowing significantly different pressures to be safely delivered to each animal for individualized support. CONCLUSIONS: In settings of limited ventilator availability, systems can be developed to allow increased delivery of ventilator support to patients. This enables more rapid deployment of ventilator capacity under constraints of time, space and financial cost. These systems can be smaller, lighter, more readily stored and more rapidly deployable than ventilators. However, optimizing ventilator support for patients with individualized ventilation parameters will still be dependent upon ease of use and the availability of medical personnel.

Airflows inside passenger cars and implications for airborne disease transmission.

Transmission of highly infectious respiratory diseases, including SARS-CoV-2, is facilitated by the transport of exhaled droplets and aerosols that can remain suspended in air for extended periods of time. A passenger car cabin represents one such situation with an elevated risk of pathogen transmission. Here, we present results from numerical simulations to assess how the in-cabin microclimate of a car can potentially spread pathogenic species between occupants for a variety of open and closed window configurations. We estimate relative concentrations and residence times of a noninteracting, passive scalar-a proxy for infectious particles-being advected and diffused by turbulent airflows inside the cabin. An airflow pattern that travels across the cabin, farthest from the occupants, can potentially reduce the transmission risk. Our findings reveal the complex fluid dynamics during everyday commutes and nonintuitive ways in which open windows can either increase or suppress airborne transmission.