Stormwater retention performance of tree integrated infiltration trenches designed for suburban streetscapes.

The volume of stormwater generated by streetscapes in cities is a primary driver of urban stream degradation. Large infiltration trenches can be integrated into streetscapes to potentially retain large volumes of runoff and increase growth rates of nearby trees. To test this, a field study was conducted where three structural soil infiltration trenches receiving runoff (12 m long, 0.6 m wide and 0.6 deep) were installed alongside a carpark in Melbourne, Australia, with sizing determined by space constraints in a typical streetscape. The three structural soil trenches had raised outflow drainage, which created internal water storage for runoff received from a carpark. To separate the effects on tree growth of i) the presence of structural soil from ii) passive irrigation into the structural soil, three structural soil trenches (6 m long, 0.6 m wide and 0.6 deep) not receiving runoff and without outflow drainage were also installed. Runoff capture, exfiltration, outflow and tree growth was monitored over 19 months. Only one system performed close to the design intent and retained 18 % of runoff, due to slow soil exfiltration rates (<0.1 mm h-1). Compacted soil generated pervious-area runoff that filled the structural soil trenches not receiving impervious-area runoff from the carpark. Tree growth near these structural soil trenches was poor (59 % relative growth) compared with trees receiving runoff from the carpark (112 % relative growth), due to a lack of drainage, emphasising the need for drainage of stormwater systems in heavy textured soils to promote tree growth. This study highlights that options for creating storage for stormwater in streetscapes have the potential to meet local runoff infiltration targets. However, meeting local runoff volume reduction targets will require alternative ways to reduce surface runoff.

Interactions between vegetation, sedimentation and flood inundation levels in wetlands.

Wetlands produce key ecosystem services to mitigate the impacts of peak flows caused by pluvial or fluvial floods or storm surges. Sediment floods were characterized by a peak flow flowing over a simulated wetland, populated with two natural species. Floods have been drawn as flows of height H, into waters of height h, where H > h. Peak flow along the flume passed through: peak flow adjustment; peak flow; drag-dominated peak flow; and gravity current regimes. For high inundation wetland levels, settling rates of coarse and fine sediment were similar during the peak flow regime. At larger distances, sedimentation decreased monotonically, with higher sedimentation of fine particles. For low inundation levels, the sedimentation rate during the drag-dominated peak flow regime was higher for coarse particles. Vegetation decreased the inundation level needed for enhancing sedimentation. Our study then adds practical knowledge at considering that the synergies between the vegetation and the inundation level may enhance wetland services such as the mitigation of pluvial, fluvial or coastal floodings.

A novel positive end-expiratory pressure titration using electrical impedance tomography in spontaneously breathing acute respiratory distress syndrome patients on mechanical ventilation: an observational study from the MaastrICCht cohort.

There is no universally accepted method for positive end expiratory pressure (PEEP) titration approach for patients on spontaneous mechanical ventilation (SMV). Electrical impedance tomography (EIT) guided PEEP-titration has shown promising results in controlled mechanical ventilation (CMV), current implemented algorithm for PEEP titration (based on regional compliance measurements) is not applicable in SMV. Regional peak flow (RPF, defined as the highest inspiratory flow rate based on EIT at a certain PEEP level) is a new method for quantifying regional lung mechanics designed for SMV. The objective is to study whether RPF by EIT is a feasible method for PEEP titration during SMV. Single EIT measurements were performed in COVID-19 ARDS patients on SMV. Clinical (i.e., tidal volume, airway occlusion pressure, end-tidal CO2) and mechanical (cyclic alveolar recruitment, recruitment, cumulative overdistension (OD), cumulative collapse (CL), pendelluft, and PEEP) outcomes were determined by EIT at several pre-defined PEEP thresholds (1-10% CL and the intersection of the OD and CL curves) and outcomes at all thresholds were compared to the outcomes at baseline PEEP. In total, 25 patients were included. No significant and clinically relevant differences were found between thresholds for tidal volume, end-tidal CO2, and P0.1 compared to baseline PEEP; cyclic alveolar recruitment rates changed by -3.9% to -37.9% across thresholds; recruitment rates ranged from - 49.4% to + 79.2%; cumulative overdistension changed from - 75.9% to + 373.4% across thresholds; cumulative collapse changed from 0% to -94.3%; PEEP levels from 10 up to 14 cmH2O were observed across thresholds compared to baseline PEEP of 10 cmH2O. A threshold of approximately 5% cumulative collapse yields the optimum compromise between all clinical and mechanical outcomes. EIT-guided PEEP titration by the RPF approach is feasible and is linked to improved overall lung mechanics) during SMV using a threshold of approximately 5% CL. However, the long-term clinical safety and effect of this approach remain to be determined.

Reliability and validity of cough peak flow measurements in myasthenia gravis.

Decreased cough strength in myasthenia gravis (MG) leads to aspiration and increases the risk of MG crisis. The aim of this study was to clarify the reliability and validity of cough peak flow (CPF) measurements in MG. A total of 26 patients with MG who underwent CPF measurements using the peak flow meter by themselves were included. MG symptoms were evaluated by pulmonary function tests and clinical MG assessment scales before and after immune-treatments. The relationship between CPF and pulmonary function tests and MG comprehensive were assessed. The cut-off value of CPF for aspiration risk was determined and the area under the curve (AUC) was calculated. The intraclass correlation coefficient was more than 0.95 for pre-and post-treatment. Positive correlations were found between CPF and almost all spirometric values as well as between the differences of pre-and post-treatment in CPF and quantitative myasthenia gravis score. The CPF for identifying the aspiration risk was used to calculate the CPF cut-off value of 205 L/min with a sensitivity of 0.77, specificity of 0.90, and AUC of 0.85. The CPF, a convenient measure by patients themselves, has a high reliability in patients with MG, and is a useful biomarker reflecting MG symptoms.

Effect of Inspiratory Muscle Training on Cough Strength in Older People With Frailty: A Single-Blind Randomized Controlled Trial.

OBJECTIVE: To investigate the effect of inspiratory muscle training (IMT) on cough strength in older people with frailty. DESIGN: Single-blind randomized controlled trial. SETTING: Day health care centers at 2 sites. PARTICIPANTS: Older people with frailty (N=60). INTERVENTIONS: Eligible people were randomly assigned to receive IMT program in addition to general exercise training (IMT group), or general exercise training alone (control group). The IMT group performed training using a threshold IMT device with the load set at 30% of maximum inspiratory mouth pressure in addition to the general exercise training program throughout the 8 weeks. The IMT took place twice a day and each session consisted of 30 breaths. MAIN OUTCOME MEASURES: Primary outcome was cough strength, measured as the cough peak flow (CPF), at the beginning and the end of the program. RESULTS: Data from 52 participants (26 in each group) were available for the analysis. The mean age was 82.6 years; 33% were men. The change in CPF at the end of the program was 28.7±44.4 L/min in the IMT group and -7.4±26.6 L/min in the control group. A linear regression model showed that the presence or absence of IMT was associated with changes in CPF (mean difference between groups, 36.3; 95% confidence interval, 16.7-55.9; effect size, 0.99). CONCLUSIONS: IMT may be a useful intervention to improve cough strength in frail older people.

Early-Life Exposure to War and Later-Life Physical Functional Health.

OBJECTIVES: A growing body of research shows that early-life exposure to war has adverse effects on later-life health. Research has emphasized the importance of exposure timing implicating domain-specific developmental processes and associated critical/sensitive periods. This study looks at the impacts of early childhood war exposure and the repercussions for later-life physical and functional health, with a focus on time of exposure as a source of variability. METHODS: We use residential histories from the Survey of Health Ageing, and Retirement in Europe linked to external data on the location and timing of hostilities to examine the impact of early-life exposure to World War II on later-life physical and functional health. RESULTS: Exposure to war increases the risk of objective (grip strength, chair rise, and peak expiratory flow) and self-reported (mobility limitations and activities of daily living) measures of functional health. Effects are especially pronounced for those born during the war and for those with more prolonged exposures. There is little evidence that the impact of war is mediated by war-related hardships, socioeconomic conditions, health behaviors, or adult chronic disease. DISCUSSION: Our results suggest early-life exposure to war has a lasting impact on physical functional health. Exposure appears to largely operate via direct effects, indicative of altered initial development of physical capacity in early life. Because exposure was so pervasive among some cohorts of older individuals, understanding the health of present older European populations requires wrestling with the residual consequences of wartime exposure at the start of their lives.

Cough flows as a criterion for decannulation of autonomously breathing patients with tracheostomy tubes.

BACKGROUND: Adequate cough or exsufflation flow can indicate an option for safe tracheostomy decannulation to noninvasive management. Cough peak flow via the upper airways with the tube capped is an outcome predictor for decannulation readiness in patients with neuromuscular impairment. However, this threshold value is typically measured with tracheotomy tube removed, which is not acceptable culturally in China. The aim of this study was to assess the feasibility and safety of using cough flow measured with tracheostomy tube and speaking valve (CFSV) > 100 L/min as a cutoff value for decannulation. STUDY DESIGN: Prospective observational study conducted between January 2019 and September 2022 in a tertiary rehabilitation hospital. METHODS: Patients with prolonged tracheostomy tube placement were referred for screening. Each patient was assessed using a standardized tracheostomy decannulation protocol, in which CFSV greater than 100 L/min indicated that the patients' cough ability was sufficient for decannulation. Patients whose CFSV matched the threshold value and other protocol criteria were decannulated, and the reintubation and mortality rates were followed-up for 6 months. RESULTS: A total of 218 patients were screened and 193 patients were included. A total of 105 patients underwent decannulation, 103 patients were decannulated successfully, and 2 patients decannulated failure, required reinsertion of the tracheostomy tube within 48 h (failure rate 1.9%). Three patients required reinsertion or translaryngeal intubation within 6 months. CONCLUSIONS: CFSV greater than 100 L/min could be a reliable threshold value for successful decannulation in patients with various primary diseases with a tracheostomy tube. TRIAL REGISTRATION: This observational study was not registered online.

The storm runoff management strategy based on agricultural ditch nutrient loss characteristics in Erhai Lake, China.

Initial flush management is an effective measure to control non-point source pollution (NPSP) in storm runoff. However, determining the parameter of the initial flush in different areas may pose challenges in storm runoff management strategies. To address this issue, Erhai Lake in China, Yunnan-Guizhou Plateau, was selected as an example for the study. Erhai Lake is a typical mesotrophic lake with the profound influence of NPSP. The NPSP control strategy in this area will provide a valuable reference for other lakes. In 2021, 289 storm events and 190 ditchwater samples were detected around Erhai Lake. The average flow in the ditches ranged from 0.004 to 0.147 m3/s, the instant total nitrogen (TN) concentration ranged from 0.28 to 91.43 mg/L, and the instant total phosphorus (TP) concentration ranged from 0.26 to 7.35 mg/L in the storm events. It was found that the concentration of pollutants was lower than expected in the initial flush period. Instead, the event mean concentrations of TN and TP were 9.3 and 2.1 times higher than in the wet seasons, showing high nutrient concentration levels throughout the entire rainfall period. To manage storm runoff effectively, a flow-processes-division method was proposed to analyze the inflow condition and pollutant removal rate in different runoff periods. The peak flow interception strategy was recommended as the optimal stormwater management plan, as it showed the highest inflow conditions and 50% pollutant removal rate. Considering the need to reduce the constant flush of stormwater runoff, it is essential to establish a healthy water cycle system to alleviate NPSP and raise the Erhai water level. The storm runoff management method can serve as a practical tool for lake areas that do not exhibit initial flush characteristics.

Interpretation of Spirometry, Peak Flow, and Provocation Testing for Asthma.

Spirometry plays a crucial role in the diagnosis of asthma. The hallmark spirometry finding of expiratory airflow variability can be demonstrated in several ways including peak airflow and bronchodilator and bronchoprovocation testing. Challenges of overdiagnosis and underdiagnosis underscore the need to consider clinical context while interpreting these tests. A meticulous and multifaceted approach prioritizing objective testing is imperative while diagnosing asthma.

Left atrial appendage peak flow velocity predicts improvement in mitral regurgitation after atrial fibrillation ablation.

BACKGROUND: Mitral regurgitation (MR) is associated with an increased risk of developing atrial fibrillation (AF) and high AF recurrence ratio after ablation. Left atrial appendage (LAA) is involved in left atrium (LA) pressure modulation and LAA peak flow velocity (LAAV) is validated as an indicator of LA contractile and reservoir function. LA function is related to the MR pathology, but the relationship between LAAV and improvement in MR after ablation remains unknown. METHODS: The present study included AF patients with moderate or severe MR from the Osaka Rosai Atrial Fibrillation ablation (ORAF) registry. We evaluated MR severity one-year post-ablation and assigned the patients based on MR improvement (at least a one-grade improvement in MR over one year) and investigated the impact of the relevant factors, including LAAV, on MR improvement. RESULTS: This study population included a total of 289 patients [paroxysmal AF (PAF), 112 patients; persistent AF (PerAF), 177 patients]. Kaplan-Meier analysis demonstrated that the patients with MR improvement had a significantly lower risk of late arrhythmia recurrence than those without (log-rank p < 0.001). MR improvement was observed in 56.3 % (63/112) of PAF patients and 55.4 % (98/177) of PerAF patients. Multiple regression analysis showed that LAAV was an independent and significant determinant of MR improvement post-ablation in both PAF and PerAF patients (p = 0.037 and p = 0.018, respectively), in addition to age and hemoglobin in PerAF patients (p = 0.045 and p = 0.048, respectively). CONCLUSION: LAAV can predict an improvement in MR after catheter ablation in both PAF and PerAF patients.

Using integrated GIS and hydrological analysis for sizing culverts of multiple channel crossings at the flooded section of the Daboya-Mankarigu Road (IR10) in Ghana.

A culvert is an important structure in Road construction to allow the conveyance of Channels crossing the road. Culverts are sized for a road to accommodate the volume of water crossing the road network to avoid flooding. Ghana Highways has a standard manual for culvert sizing at channel crossing. This manual serves as a guide for the proper sizing of culverts, however, lots of culverts have been found to have failed. Among the reasons for the failure of culverts could be under-sizing, urbanization, climate change, lack of maintenance, etc. The Daboya-Mankarigu Road is situated in the Savanah Region of Ghana in the North Gonja District. The section of the road from Chainage 9 + 075 to 10 + 200 has been experiencing flooding from 2020 to 2021 with a flood depth of 3.315 m in 2020 and 2.00 m in 2021. This study seeks to use integrated GIS and hydrological-based methods to propose new culverts to supplement the existing culverts to control flooding at section (9 + 075 to 10 + 200) of Daboya-Mankarigu Road (IR10). Geographic Information system (GIS) model (SWAT), Hydrological and hydraulic models were used to determine the peak flow at the catchment to Propose new culverts to supplement the existing culverts. Using a design period of 25 years for culverts, the modified rational method was used to determine the Peak flow of the catchment. A 25-year peak flow of 367.155 m3/s was determined and used for hydraulic analysis of the existing culverts. From the study, the existing culvert structures at the section had a hydraulic capacity of 78.732 m3/s which could not accommodate the remaining flow of 288.423 m3/s in the catchment. An observation was made that the changes in the rainfall can cause a change in rainfall intensity. An increase in built-up areas in the catchment can also increase the runoff coefficient which can result in higher peak flow in the catchment. Climate change, change in slope, and Land use in the catchment were also determined to have a huge influence on the adequacy of culverts since the peak flow is dependent on these parameters in the catchment as the years go by. A 4No. 4 m × 4 m box culvert, 3No. 3.5 m × 3.5 m box culvert, and 13 No. 1200 mm pipe culverts with 2 each at different chainages were proposed at suitable locations to supplement the existing culverts using the HDS-5 equations in AutoCAD Civil 3D. A recommendation is made to consider the installation of these new culverts at the flood section to control flooding and avoid overtopping of water on the IR10 road section (Daboya-Mankarigu) in the north Gonja District.

Pulmonary Function Assessment in Myasthenia Gravis Patients in a National Referral Hospital in Indonesia.

Purpose: Myasthenia gravis (MG) can cause respiratory muscle weakness and the need of ventilator support. Spirometry as the gold standard for pulmonary function examination has limited availability, especially in our hospital which is only available in outpatient clinic during work hours (not in emergency room or patient room). Furthermore, all primary healthcare in Indonesia do not have spirometry equipment, thus other alternatives are required. This study aimed to analyze the relationship between a single breath counting test (SBCT), peak flow meter (PFM), and spirometry to assess pulmonary function in MG patients in a national referral hospital in Indonesia. Patients and Methods: A single-center, cross-sectional study was conducted and SBCT, PFM, and spirometry examination were performed in MG patients and healthy controls. Results: Seventy patients, aged 47.7 ± 13.4 years old, participated in this study. SBCT, forced vital capacity first second (FVC1), and forced expiratory volume first second (FEV1) value between MG patients and healthy controls showed a significant difference, in which healthy controls have higher SBCT, FVC1, and FEV1 values (p = 0.000, p = 0.000 and p = 0.001 respectively). There was a significant difference between PFM with SBCT and FVC1 value in MG patients. Strong correlation was found between SBCT and FVC1 in MG patients. Conclusion: MG patients had worse pulmonary function compared to healthy controls. SBCT and PFM examination have a significant correlation with FVC1 in MG patients. Therefore, SBCT and PFM can be used as a bedside tool to detect respiratory impairment in MG patients.

Comparative Study on Chronic Obstructive Pulmonary Disease Screening Tools in Primary Healthcare Institutions in Beijing, China.

Background: Chronic obstructive pulmonary disease (COPD) has a high incidence rate in China, but the diagnosis rate remains insufficient. This study aimed to explore and compare COPD screening tools for primary healthcare institutions in China. Purpose: Exploring COPD Screening Tools and Their Combined Use for Primary Healthcare Institutions in China. Patients and Methods: From September 2022 to March 2023, a screening for COPD was conducted among residents aged 35 years and above in primary healthcare institutions in Beijing, China. The screening involved the use of the CAPTURE scale, COPD-SQ scale, and peak expiratory flow rate test. Any positive results from these screening tests were followed by further pulmonary function testing to confirm the diagnosis. Sensitivity, specificity, positive predictive value, negative predictive value, and receiver operating characteristic (ROC) curves were calculated for each screening tool alone and in combination. Results: A total of 986 individuals completed the screening tests. The positive rates for the CAPTURE scale, COPD-SQ scale, and peak flow meter screening were 41.78%, 29.11%, and 52.03%, respectively. Of the participants, 166 (24.09%) underwent pulmonary function tests, with an average age of 61.69±13.68 years. The peak flow meter screening showed the highest sensitivity (83.78%) when used alone, while the COPD-SQ scale exhibited the best specificity (59.69%), positive predictive value (31.58%), and negative predictive value (58.56%). Significant differences (P<0.05) were observed between any two of the three screening tools. Among the combinations, the peak flow meter screening + COPD-SQ scale showed the highest accuracy, with a Youden index of 0.277 and an AUC of 0.638. Conclusion: There is variation in the accuracy of existing screening tools for COPD when used alone. For primary healthcare institutions, the optimal COPD screening tool is the combination of peak flow meter screening and the COPD-SQ questionnaire. If limited by screening equipment conditions, the COPD-SQ questionnaire can be used alone for screening.

Correlation between Respiratory Dysfunction and Dysphagia in Individuals with Acute Traumatic Cervical Spinal Cord Injury.

Introduction: Aspiration pneumonia is one of the most frequent and fatal life-threatening complications among individuals with acute traumatic cervical spinal cord injury (CSCI). However, the mechanism of dysphagia among individuals with CSCI is not well understood. Morbidity and mortality associated with CSCI may result from the interplay between respiratory dysfunction and dysphagia. This study aimed to elucidate the effect of respiratory dysfunction on the swallowing function of individuals with acute traumatic CSCI. Methods: A prospective cohort study was conducted involving 54 individuals with acute traumatic CSCI who were admitted within 2 weeks following injury. Dysphagia was evaluated using the Dysphagia Severity Scale (DSS) and the Functional Oral Intake Scale (FOIS). Respiratory function was evaluated by measuring the cough peak flow (CPF), forced expiratory volume in 1 s (FEV1.0), FEV1.0/forced vital capacity (FEV1.0%), and percent vital capacity (%VC). We recorded these parameters at weeks 2, 4, 8, and 12 following injury and analyzed pertinent changes over time and significant correlations. Results: Among 54 individuals (46 men and 8 women) recruited in this study, 48 (88.9%) had restrictive ventilatory impairment and 17 (31.5%) had severe dysphagia (DSS level 1-4) 2 weeks following injury. However, respiratory function and swallowing function significantly improved thereafter. CPF, FEV1.0, and %VC were significantly correlated with the severity of dysphagia during each period. Conclusions: Restrictive ventilatory impairment, poor cough force, and dysphagia are closely related, and the evaluation of respiratory function plays an important role in evaluating dysphagia.

Comparison of electrical impedance tomography and spirometry-based measures of airflow in healthy adult horses.

Electrical impedance tomography (EIT) is a non-invasive diagnostic tool for evaluating lung function. The objective of this study was to compare respiratory flow variables calculated from thoracic EIT measurements with corresponding spirometry variables. Ten healthy research horses were sedated and instrumented with spirometry via facemask and a single-plane EIT electrode belt around the thorax. Horses were exposed to sequentially increasing volumes of apparatus dead space between 1,000 and 8,500 mL, in 5-7 steps, to induce carbon dioxide rebreathing, until clinical hyperpnea or a tidal volume of 150% baseline was reached. A 2-min stabilization period followed by 2 minutes of data collection occurred at each timepoint. Peak inspiratory and expiratory flow, inspiratory and expiratory time, and expiratory nadir flow, defined as the lowest expiratory flow between the deceleration of flow of the first passive phase of expiration and the acceleration of flow of the second active phase of expiration were evaluated with EIT and spirometry. Breathing pattern was assessed based on the total impedance curve. Bland-Altman analysis was used to evaluate the agreement where perfect agreement was indicated by a ratio of EIT:spirometry of 1.0. The mean ratio (bias; expressed as a percentage difference from perfect agreement) and the 95% confidence interval of the bias are reported. There was good agreement between EIT-derived and spirometry-derived peak inspiratory [-15% (-46-32)] and expiratory [10% (-32-20)] flows and inspiratory [-6% (-25-18)] and expiratory [5% (-9-20)] times. Agreement for nadir flows was poor [-22% (-87-369)]. Sedated horses intermittently exhibited Cheyne-Stokes variant respiration, and a breath pattern with incomplete expiration in between breaths (crown-like breaths). Electrical impedance tomography can quantify airflow changes over increasing tidal volumes and changing breathing pattern when compared with spirometry in standing sedated horses.

Chronic respiratory diseases: A rapidly emerging public health menace.

Chronic respiratory diseases, especially the common chronic obstructive pulmonary disease (COPD) and asthma, are increasing at a swift pace. Although smoking is the most typical risk factor globally, indoor and outdoor air pollution is more important in India. Deaths due to COPD have been next to coronary heart disease since 2014. It causes about 64 deaths per lakh population. It is a chronic and progressive disease having many exacerbations. Mostly senior males are affected. Often, the exacerbation needs intensive care, which may be taxing to the limited intensive care units and may deprive other more warranting patients. The diagnosis requires spirometry, which is available only in private or government tertiary care hospitals. The mainstay of treating both diseases is the inhalation of bronchodilators with or without steroids. The diagnosis and treatment are costly, and treatment is required lifelong. Reduction in risk factors is a challenging and long journey. It requires behavioral change communication. The government in the health sector has critical options. On the one hand, the disease is increasing for various reasons; on the other hand, resources are enormously required for prevention and management. The ASHA system and health and wellness centers, which have not been given due importance, can screen, diagnose, and manage majorly patients. Public health specialists should forcefully advocate for resources required for training and equipment.

Mechanical Insufflation-Exsufflation Implementation and Management, Aided by Graphics Analysis.

Mechanical insufflation-exsufflation (MIE) facilitates airway clearance to mitigate respiratory infection, decompensation, and ultimately the need for intubation and placement of a tracheostomy tube. Despite widespread adoption as a respiratory support intervention for motor neuron disease, muscular dystrophy, spinal cord injury, and other diseases associated with ventilatory pump failure and ineffective cough peak flow, there is debate in the clinical community about how to optimize settings when MIE is implemented. This article will demonstrate the clinical utility of MIE graphics in titrating the initial MIE settings, guiding upper airway and lung protective strategies and providing insight to clinicians for ongoing clinical management.

Mechanical Insufflation-Exsufflation: Considerations for Improving Clinical Practice.

The provision of mechanical insufflation-exsufflation (MI-E) devices to enhance cough efficacy is increasing. Typically, MI-E devices are used to augment cough in patients with neuromuscular disorders but also in patients who are weak in an acute care setting. Despite a growing evidence base for the use of these devices, there are barriers to the provision of MI-E, including clinician lack of knowledge and confidence. Enhancing clinician education and confidence is key. Individualized or protocolized approaches can be used to initiate MI-E. Evaluation of MI-E efficacy is critical. One method to evaluate effectiveness of MI-E is the MI-E-assisted cough peak flow (CPF). However, this should always be considered alongside other factors discussed in this review. The purpose of this review is to increase the theoretical understanding of the provision and evaluation of MI-E and provide insight into how this knowledge can be applied into clinical practice. Approaches to initiation and titration can be selected based on the clinical situation, patient diagnosis (including and beyond neuromuscular disorders), and clinician's confidence.

Regional peak flow as a novel approach to assess regional pulmonary mechanics by electrical impedance tomography: an observational validation study.

Background: Spontaneous breathing efforts during mechanical ventilation are a widely accepted weaning approach for acute respiratory distress syndrome (ARDS) patients. These efforts can be too vigorous, possibly inflicting lung and diaphragm damage. Higher positive end expiratory pressure (PEEP) levels can be used to lower the magnitude of vigorous breathing efforts. Nevertheless, PEEP titrating tools are lacking in spontaneous mechanical ventilation (SMV). Therefore, the aim is to develop an electrical impedance tomography (EIT) algorithm for quantifying regional lung mechanics independent from a stable plateau pressure phase based on regional peak flow (RPF) by EIT, which is hypothetically applicable in SMV and to validate this algorithm in patients on controlled mechanical ventilation (CMV). Methods: The RPF algorithm quantifies a cumulative overdistension (ODRPF) and collapse (CLRPF) rate and is validated in a prospective cohort of mechanically ventilated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) patients on CMV. ODRPF and CLRPF are compared with compliance-based cumulative overdistension (ODP500) and collapse (CLP500) rates from the Pulmovista 500 EIT device at multiple PEEP levels (PEEP 10 cmH2O to PEEP 24 cmH2O) in EIT measurements from CMV patients by linear mixed models, Bland-Altman analysis and intraclass correlation coefficient (ICC). Results: Seventy-eight patients were included. Linear mixed models revealed an association between ODRPF and ODP500 of 1.02 (0.98-1.07, P<0.001) and between CLRPF and CLP500 of 0.93 (0.80-1.05, P<0.001). ICC values ranged from 0.78 to 0.86 (P<0.001) for ODRPF and ODP500 and from 0.70 to 0.85 (P<0.001) for CLRPF and CLP500 (PEEP 10 to PEEP 24). The mean bias between ODRPF and ODP500 in these PEEP levels ranged from 0.80% to 4.19% and from -1.31% to 0.13% between CLRPF and CLP500. Conclusions: A RPF approach for quantifying regional lung mechanics showed a moderate to good agreement in coronavirus disease 2019 (COVID-19) related ARDS patients on CMV compared to the compliance-based approach. This, in addition to being independent of a plateau pressure phase, indicates that the RPF approach is a valid method to explore for quantifying regional lung mechanics in SMV.

Relationship between left atrial appendage peak flow velocity and nonvalvular atrial fibrillation recurrence after cryoablation.

Background: Previous studies revealed the connection between left atrial appendage peak flow velocity (LAA-PEV) and postoperative persistent atrial fibrillation (AF) recurrence. Yet, this association is not necessarily generalizable to persistent AF patients undergoing initial cryoballoon ablation due to current gaps in the literature. Methods: We prospectively studied 74 consecutive individuals with persistent atrial fibrillation undergoing a cryoballoon ablation for the first time between January 2018 and January 2020. Before ablation, LAA-PEV was documented by transesophageal echocardiography (TEE). Subsequently, demographic information and other clinical characteristics of these participants were collected. A 96-h continuous cardiac monitor was reviewed regularly for recurrence of atrial fibrillation. Cox proportional hazards regression was used to investigate LAA-PEV as well as other clinical characteristics as a predictor of AF recurrence. Results: Our study found that AF recurrences had lower LAA-PEV than those without AF recurrence. A nonlinear relationship between the LAA-PEV and AF recurrence was observed in this study, which had an inflection point of 34.9. Subgroup analysis of female participants showed that LAA-PEV had a positive correlation with AF recurrence [ß = 0.8, 95% CI (0.7, 0.9), p < 0.05]. Conclusion: A low LAA-PEV is related to recurrence of atrial fibrillation and may predict AF recurrence after initial cryoballoon ablation for persistent atrial fibrillation. This finding may help improve treatment and care strategies for patients with persistent atrial fibrillation.