Noninvasive Ventilation Settings Research Articles

A comparison of two weaning strategies for non-invasive ventilation in chronic obstructive pulmonary disease patients with acute respiratory failure.

Non-Invasive Ventilation (NIV) is a crucial therapy for managing acute exacerbations of Chronic Obstructive Pulmonary Disease (COPD) with hypercapnic respiratory failure. Research has shown that NIV can decrease the rate of endotracheal intubation, length of hospital and Intensive Care Unit stays, and mortality. There are three main strategies for weaning patients off NIV: gradual reduction of NIV duration, gradual reduction of NIV pressure support, and immediate cessation of NIV. To compare the rate of successful withdrawal of COPD patients with acute hypercapnic respiratory failure, one group will use a stepwise reduction of duration of NIV, while the other group will use a stepwise reduction of pressure support. This study was a prospective observational study conducted at the Department of Pulmonary Medicine, Institute of Chest Diseases, Government Medical College, Kozhikode, over a period of 15months. The study population consisted of all COPD patients admitted to the Pulmonary Medicine ward or ICU with acute hypercapnic respiratory failure who were managed with non-invasive ventilation (NIV) without the need for invasive mechanical ventilation. Exclusions included patients requiring NIV for respiratory diseases other than COPD, those with significant comorbiditieslike acute left ventricular failure or fluid overload states as in chronic kidney disease, COVID-19 positive patients, patients on home NIV, patients who needed intubation early in treatment, and patients unwilling to participate in the study. The sample size was 140. Initial NIV settings and other management decisions prior to enrolment in the study were made by the treating physician according to standard protocols. Once weaning criteria were met (i.e., arterial pH > 7.35, SpO2 ≥ 90% at an FiO2 ≤ 50%, respiratory rate ≤ 25 breaths per minute, heart rate ≤ 120 beats per minute, systolic BP > 90mm Hg, and no signs of respiratory distress), patients were assigned to either group 1 or group 2 by purposive sampling. Group 1: stepwise reduction of duration of NIV use, with a reduction to 16h per day on day 1 of enrolment, 12h on day 2 (including 6-8h of nocturnal NIV), 6-8h on day 3, and NIV withdrawal on day 4. Group 2: stepwise reduction of pressure support, with pressure support reduced by 2-4cm every 4-6h until Inspiratory Positive Airway Pressure is < 8cm H2O and Expiratory Positive Airway Pressure is < 4cm H2O, followed by NIV withdrawal. The clinical outcome was classified as either improved or weaning failure. Improved was defined as an objective or subjective sense of improvement. Weaning failure was defined as the presence of any of the following: respiratory rate ≥ 25/minute or increase of ≥ 50% from baseline, heart rate ≥ 140/minute or increase of ≥ 20% from baseline, SpO2 ≤ 90% on FiO2 ≥ 50%, arterial pH ≤ 7.35, or respiratory distress. Data was collected using a pro forma that included demographic details, smoking status, GOLD COPD category, comorbidities, and vital signs. ABG parameters, NIV settings at the time of hospital admission, at the time of study enrolment, and 48h after weaning were also recorded. Independent sample t-test was used to test the statistical significance of the difference between means of variables between the two groups. Pearson Chi square test and Fisher's exact test were used to compare categorical variables between the groups. A p-value of < 0.05 was considered statistically significant. NIV was successfully withdrawn in 56/70 (80%) and 50/70 (71.4%) patients in Groups 1 and 2, respectively. This difference was not statistically significant. The length of hospital stay was longer in the stepwise reduction of duration group (Group 1), but this was not statistically significant. On comparison of two methods of NIV withdrawal, it was found that neither method is superior to the other in terms of weaning failure, intubation rates, and average length of hospital stay.

Factors Associated With Change in S3-NIV Score Over Time in People With Chronic Respiratory Failure Treated With Long-Term Home Noninvasive Ventilation

IntroductionMonitoring changes in symptoms over time during long-term nocturnal home non-invasive ventilation (NIV) using patient-reported outcome measures is crucial. This study aimed to identify factors associated with changes in the S3-NIV total score, its two domains (“respiratory symptoms” and “sleep and NIV-related side effects”) and individual item responses. MethodsWe conducted a retrospective, longitudinal data analysis of a cohort of adults with chronic respiratory failure treated with NIV. Data were obtained from a French homecare provider. Multivariate linear and multinomial ordinal mixed effect models were used to identify factors associated with changes in S3-NIV scores over time. ResultsMedian follow-up was 2 years for 2135 participants. Each participant completed a median of five S3-NIV questionnaires; totaling 11,359 analyzed questionnaires. Type of respiratory condition, sex, age and time since NIV initiation were associated with change in S3-NIV score over time. NIV adherence was not associated with total S3-NIV score but high adherence was associated with more severe respiratory symptoms and an improvement in sleep and NIV-related side effects during the follow-up. Intensity of pressure support was associated with a lower total S3-NIV score and more side effects. Face masks and supplemental oxygen were associated with a lower S3-NIV total score. ConclusionChanges in S3-NIV scores over time are associated with the individual's characteristics and NIV settings. Analysis of the two domains and individual items of the S3-NIV could increase understanding of the difficulties experienced by people on NIV.

Noninvasive Home Mechanical Ventilation for Stable Hypercapnic COPD: A Clinical Respiratory Review from Canadian Perspectives.

Acute short-term noninvasive ventilation (NIV) for hypercapnic respiratory failure in chronic obstructive pulmonary disease (COPD) has well-established benefits; however, the role of long-term home NIV remains controversial. In the past decade, studies utilizing aggressive NIV settings to maximally reduce carbon dioxide levels (PaCO2) have resulted in several positive clinical trials and led to updated guidelines on home NIV for stable hypercapnic COPD patients. This clinical respiratory review discusses the high-intensity NIV approach, summarizes recent key trials and guidelines pertaining to home NIV in COPD, and considers key clinical questions for future research and application in the Canadian context. With recent evidence and Canadian Thoracic Society (CTS) guidelines supporting the use of NIV in carefully selected COPD patients with persistent daytime hypercapnia, we believe it is time to reconsider our approach.

Procedure videos to support rare clinical procedures in acute cardiac nursing, an implementation evaluation

Abstract Funding Acknowledgements Type of funding sources: Public hospital(s). Main funding source(s): Central Coast Local Health District Research Grant. Background Cardiology procedures are often lifesaving and time-critical, but some are so infrequent that nurses may have rarely encountered them in practice. Videos demonstrating rare procedures can potentially support clinicians performing rare clinical procedures. We evaluated using locally created nursing clinical procedure videos as an adjunct to traditional written procedures. Purposes This study evaluated the implementation of 7 newly created clinical procedure videos on temporary cardiac pacing (n=3), non-invasive ventilation (NIV) (n=2) and pericardiocentesis (n=2). Methods A pre/ post -implementation Survey based on the Theoretical Domains Framework (TDF), Clinical Reasoning Cycle and the Spielberger State-Trait Anxiety Inventory (STAI) was distributed via email and Facebook groups to over 500 eligible nurses in the implementation sites. In addition, data from the hosting platform Vimeo for the implementation period and procedure numbers (15 October 2020 to 15 March 2021) were analysed. Results 122 respondents, 86% female, viewed the videos, mean age of 40.75 years (20 to 71 years). The most common procedure during the implementation period was NIV (n=170), followed by Pericardiocentesis (n=7) and Temporary Cardiac Pacing (n=5). The total number of video views over the 6 months was 598, temporary pacing-preparation (n=152), NIV Mask why and when (n=137), NIV Set up and Patient Care (n=89), Pacing: Procedure (n=62), Cardiac Tamponade (n=52), Pacing: Threshold testing and Pericardiocentesis Procedure (n=51 each). Participants agreed /strongly agreed that video procedures increased their recall (93.8%), made learning a better experience (98.3%), and was time-saving (88.0%) (Figure 2). Participants preferred videos to be an adjunct to existing written procedures and not a replacement (78%). Major themes from qualitative feedback included participants describing them as "clear and easy to understand" and the benefits of videos for rare procedures "Rarely seen in ED easy to follow and fast refresher when the procedure is time critical". Prior to implementation, the mean score for state anxiety before a rare procedure was 41.43 (SD= 9.307) with scores over 40 indicating clinically significant levels of anxiety. Older age and a higher number of years in the role were significantly correlated with lower anxiety levels (r = -0.144 p = .037; and r = 0.532 p = .000) perceived anxiety related to rare procedures did not significantly change from pre- to post-implementation. Conclusion Clinical procedure videos at the point of care are acceptable and valued. Findings suggest videos are a useful adjunct to written procedures for time-critical or rare procedures.Figure 2:Experience with video.

Introducing helmet non-invasive ventilation during COVID-19 pandemic: Early experience of two centres.

The helmet is a novel interface for delivering non-invasive ventilation (NIV). We conducted a case series to characterize introduction of the helmet interface in both COVID and non-COVID patients at two-centres. We enrolled all patients with respiratory failure admitted to the Juravinski Hospital (Hamilton, Canada) and St. Joseph's Health Center (Syracuse, New York) between November 1, 2020 and June 30, 2021 who used the helmet interface (Intersurgical StarMed) as part of this introduction into clinical practice. We collected patient demographics, reason for respiratory failure, NIV settings, device-related complications and outcomes. We report respiratory therapist's initial experiences with the helmet using descriptive results. We included 16 patients with a mean age of 64.3 ± 10.9 years. The most common etiology for respiratory failure was pneumonia (81.3%). The median duration of NIV during the ICU admission was 67.5 (15.3, 80.8) hours, with a mean maximum PS of 13.9 ± 6.6 cm H2O and a mean maximum PEEP of 10.4 ± 5.1 cm H20. Three patients (18.7%) did not tolerate the helmet. Ten (62.5%) patients ultimately required intubation, and 7 (43.4%) patients died while in the ICU. The most common reason for intubation was worsening hypoxia (70%). No adverse events related to the helmet were recorded. Over the 8-month period of this study, we found that the helmet was well tolerated in over 80% of patients, although, more than half ultimately required intubation. Randomized controlled trials with this device are required to fully assess the efficacy of this interface.

Noninvasive Ventilation Automated Technologies: A Bench Evaluation of Device Responses to Sleep-Related Respiratory Events.

Noninvasive ventilation (NIV) is the reference standard treatment for most situations of chronic respiratory failure. NIV settings must be titrated to both preserve upper-airway patency and control hypoventilation. Automatic adjustment of pressure support (PS) and expiratory positive airway pressure (EPAP) may facilitate the initiation and follow-up of domiciliary NIV. However, whether the automatic-adjustment algorithms embedded into current devices accurately detect, respond to, and score common sleep-related respiratory events remains unclear. A bench was set up to simulate central hypopnea (CH), central apnea (CA), obstructive hypopnea (OH), and obstructive apnea (OA). Four home ventilators were evaluated, with their dedicated modes for automatic PS and EPAP adjustment. All 4 devices increased PS during CH, CA, and OH. However, PS adjustment varied widely in magnitude, with tidal volumes within 100 ± 20% of the target being provided by only 3 devices for CH, one for CA, and one for OH. Two devices increased EPAP for OH and 3 for OA, including one that also increased EPAP for CA. Only 2 devices scored residual hypopnea after simulated CA, and only one scored a residual event after OH. One device scored no event. Current NIV devices differed markedly in their responses to, and reporting of, standardized sleep-related respiratory events. Further improvements in embedded NIV algorithms are needed to allow more widespread out-of-laboratory initiation and follow-up of NIV.

Potential rebreathing of carbon dioxide during noninvasive ventilation provided by critical care ventilator

BackgroundCritical care ventilators are frequently used to provide noninvasive ventilation (NIV) support to critically ill patients. Questions remain regarding carbon dioxide (CO2) clearance while using a critical care ventilator and dual limb circuit with various patient interfaces. The purpose of this study is to determine the positive end expiratory pressure (PEEP) level required to effectively washout CO2 for full-face and oronasal masks when using a dual limb circuit.MethodThis randomized crossover trial was conducted at an academic medical center in the Midwest United States. After obtaining informed consent, eight healthy volunteers were placed on a 980 Puritan Bennett (Medtronic, Minneapolis, MN) ventilator operating in the NIV mode. All subjects performed 20 min of breathing on four levels of PEEP (0, 2, 4, and 5 cm H2O) and pressure support of 5 cm H2O. NIV settings were applied to four masks (two oronasal and two full-face masks) that were randomly selected with a 5-min washout period between each mask. The fraction of inspired carbon dioxide (FICO2) was sampled/monitored with a nasal cannula using a Capnostream 20p monitor (Medtronic, Minneapolis, MN) and reported as percentages. A Kruskal–Wallis test was used to reveal significant differences across PEEP levels. Pairwise comparisons of the groups were made using Mann–Whitney tests with a family-wise error correction.ResultsMedian (IQR) FICO2 was significantly lower 0.0% (0%–0.92%) at PEEP of 5 compared to 1.83% (0.66%–4.0%; p < 0.001) at PEEP of 0 or 1.0% (0.33%–2.66%; p = 0.002) at PEEP of 2. FICO2 was significantly lower 0.5% (0%–1.92%) at PEEP of 4 compared to PEEP of 0 (p = 0.001).ConclusionA PEEP level of at least 5 cm H2O associated with the reported leak was required to minimize the likelihood of CO2 rebreathing while using a critical care ventilator to provide NIV with a double limb circuit and full-face or oronasal masks.

Non-invasive ventilation in neuromuscular diseases: should we use higher levels of ventilatory support?

In patients with COPD, one of the leading indications for domiciliary non-invasive ventilation (NIV), a major paradigm shift has been observed over the past decade in the method for adjusting NIV settings, with the use of sufficient ventilatory support to achieve a significant reduction in PaCO2. Whether this approach may be relevant to other populations, especially slowly progressive neuromuscular diseases (NMD), is unknown. This study was conducted as a post hoc analysis from a previously published randomized controlled trial (NCT03458507). Patients with NMD treated with domiciliary NIV were stratified according to the level of ventilatory support: high-level tidal volume (HLVT; mL/kg of predicted body weight [PBW]) or high-level pressure support (HLPS), defined as a value above median value of the whole population (> 6.8mL/kgPBW or 9.0 cmH2O, respectively). Primary outcome was mean nocturnal transcutaneous CO2 pressure (PtcCO2). Secondary outcomes included adherence to NIV, leaks, and side effects. Of a total of26 patients, 13 were exposed to HLVT, with significantly lower nocturnal PtcCO2 (respectively 40.5 ± 4.2 vs. 46.3 ± 3.9mmHg, p = 0.002). A linear correlation between VT (mL/kgPBW) and mean nocturnal PtcCO2 was evidenced (r = - 0.59, 95%CI [- 0.80; - 0.25], p = 0.002). No significant impact of HLVT was found on secondary outcomes. Despite the lack of power of this post hoc analysis, our results suggest that higher levels of ventilatory support are correlated with lower PtcCO2 in patients with NMD. Further studies are desirable to assess the extent to which the level of assistance influences PaCO2 evolution in patients with slowly progressive NMD, as well as in restrictive thoracic disorders.

Delirium incidence and risk factors in patients undergoing non-invasive ventilation for acute respiratory failure: a multicenter observational trial.

Noninvasive ventilation (NIV) still has high failure rate when used for de novo acute respiratory failure (ARF). Delirium may impact the outcome, however data regarding its incidence, timing of occurrence and clinical predictors in this subset of patients are scarce. Consecutive patients with de novo ARF subjected to NIV were recruited in 10 Italian Respiratory Intensive Care Units (RICUs) and Intensive Care Units (ICUs). Demographics and clinical features, including tolerance to interface and NIV setting were recorded on admission and during stay, whereas delirium onset and type was assessed by the Confusion Assessment Method for ICU (CAM-ICU)-7 scale and Richmond Agitation Sedation Scale (RASS) twice/per day up to a week. The association between clinical variables and the occurrence of delirium and its influence on NIV failure and other clinical outcomes were analyzed. Thirty-two out of 90 enrolled patients (36%) developed delirium over seven days upon admission; median time to onset was 48 hours (24-60). Older age (OR=2.7 [1.9-9], P=0.01), the presence of cancer OR=3.7 [2-5.4], P=0.002), sepsis (OR=1.7 [1.1-3.4], P=0.01), SOFA Score (OR=1.8 [1.1-3.1], P=0.01), low tolerance to interface (OR=3.2 [2.1-5], P=0.002), use of helmet (OR=1.9 [1.2-4.3] P=0.04), and higher PRE-DELIRIC (OR=3.5 [1.3-15], P=0.03) and BORG (OR=1.7 [1.1-4.6], P=0.02] scores were significantly associated with delirium. Delirium had high risk for NIV failure (HR=3.5 95% CI: [1.4-8.6], P=0.0002) and it significantly associated with longer RICU/ICU stay and higher mortality. Delirium onset in acute hypoxic patients undergoing NIV is frequent and negatively affects the outcome. Multiple related clinical factors should be addressed early on admission to prevent the delirium-related risk of NIV failure in these patients.

Effect of Mask Selection on the Leak Test in Ventilators Designed for Noninvasive Ventilation.

The mask leak test used for modern noninvasive ventilators can detect the leak characteristics of masks that are not recommended by the manufacturer, but it has not yet been determined whether this method is acceptable. A noninvasive ventilator equipped with a single-limb circuit and an oronasal mask was connected to a lung simulator. The ventilator was set to S/T mode, and inspiratory positive airway pressure/expiratory positive airway pressure was set to 10/5, 15/5, and 20/5 cm H2O, respectively. Eight nonmanufacturer-recommended oronasal masks were connected to the ventilator. The lung simulator was used to simulate COPD, restrictive disease, and normal lung, respectively. When switching between masks, the mask leak test was set to "Cancel" or "Start Test" in the noninvasive ventilator. The parameters displayed on the lung simulator and ventilator were recorded before and after the mask leak test. There were no significant difference before versus after the mask leak test for any lung simulator parameter, including trigger performance (ie, time from the beginning of the simulated inspiratory effort to the lowest value of airway pressure needed to trigger the ventilator, the magnitude of airway pressure drop needed to trigger, and time to trigger), inspiratory pressure delivery, PEEP, tidal volume, and displayed peak inspiratory pressure (all differences < 10%). At different noninvasive ventilation settings, tidal volumes displayed on the ventilator of the 3 masks were significantly different before and after mask leak test (all P < .05, and difference rate > 10%). The mask leak test had no effect on the ventilator performance when masks not recommended by the manufacturer were used, but tidal volume monitoring may be more accurate when some masks were used.

Duration of noninvasive ventilation is not a predictor of clinical outcomes in patients with acute exacerbation of COPD and respiratory failure.

PurposeAcute exacerbation of chronic obstructive pulmonary disease (COPD) is a major cause of mortality and morbidity. Noninvasive ventilation (NIV) is proven to be effective in the majority of patients with acute exacerbation COPD (AECOPD) complicated with respiratory failure. NIV could be lifesaving but also can delay mechanical ventilation if its efficacy is not assessed in a timely manner. In this study, we analyzed potential predictors of NIV failure in AECOPD in a tertiary medical intensive care unit (MICU). In particular, we wondered whether duration of NIV among those who eventually failed was associated with poor outcomes.MethodsA retrospective review of consecutive patients with a primary diagnosis of AECOPD requiring NIV admitted to the MICU was conducted for the period between 2012 and 2017. Baseline data included demographics, APACHE III score, albumin level, blood lactate, and blood gas elements. Additional chart review was performed to collect NIV setting parameters on presentation to the MICU. Clinical outcome variables collected included outcome and duration of NIV, duration of invasive mechanical ventilation, MICU length of stay, hospital length of stay, and in-hospital mortality. Multivariate regression analysis was performed to determine independent variables associated with clinical outcomes.ResultsThere were 370 patients who met the inclusion criteria; 53.2% were male. Mean age was 64.7 ± 11.2 years old. Mean baseline FEV1 was 34 ±17% of predicted. Patients had mean pH of 7.20 ± 0.54 and PaCO2 of 70.3 ± 28.7 on presentation; 323 patients (87.3%) were successfully weaned off NIV; 47 patients (12.7%) failed NIV and required invasive mechanical ventilation. APACHE III score was higher among patients who failed NIV (68.3±18.9 versus 48.8± 15.2, P < 0.001). In the subset of 47 patients who failed NIV requiring intubation, duration of NIV was 25.0 ± 58.8 h. Multivariate regression analysis yielded a model consisting of APACHE III score and body mass index as predictive variables for NIV failure (C-statistic = 0.809). Duration of NIV was not associated with worse clinical outcomes among patients who failed NIV.ConclusionsNIV is successful in preventing invasive mechanical ventilation in majority of patients with acute respiratory failure due to COPD. Patients with worse clinical status at presentation are more likely to fail NIV and require mechanical ventilation. In the subgroup of patients who failed NIV, duration of NIV prior to intubation was not associated with poor clinical outcomes.

Determinants of usage and nonadherence to noninvasive ventilation in children and adults with Duchenne muscular dystrophy.

Duchenne muscular dystrophy (DMD) is a neuromuscular disorder that leads to chronic respiratory insufficiency and failure. Use of home noninvasive ventilation (NIV) has been linked to improved outcomes including reduced mortality. Despite the importance of NIV, factors promoting optimal NIV usage and determinants of nonadherence have not been rigorously examined. Moreover, given that respiratory issues in DMD span between childhood and adulthood, examination across a broad age group is needed. The objectives of this study were to (1) evaluate NIV usage across a broad spectrum of patients with DMD, including both children and adults, and (2) identify biological and socioeconomic determinants of NIV usage and NIV nonadherence. We performed a retrospective review of all patients with DMD from February 2016 to February 2020 who underwent evaluation at associated pediatric and adult neuromuscular disease clinics. NIV use was determined objectively from device downloads. A priori, we defined nonadherence as < 4 hours use per night, quantified as the percentage of nights below this threshold across a 30-day period within 6 months of a clinic visit. We also assessed the average hours of NIV usage over this time period. Predictors examined included demographics, social determinants, and pulmonary function. 33 patients with DMD were identified, 29 (87%) of whom were using NIV (13 age < 21 years). Mean age was 22.9 ± 6.6 years (range 13-39 years), body mass index was 23.4 ± 10.4 kg/m2, and seated forced vital capacity was 23% ± 18% predicted. Mean nightly NIV usage was 7.4 ± 3.8 hours and mean percentage of nonadherent nights was 13% ± 30%. In univariable analysis, age did not predict use. Those with lower forced vital capacity had higher NIV usage hours (P = .01) and a trend toward less nonadherence (P = .06). Higher estimated household income demonstrated a trend toward increased usage hours and less nonadherence (both P = .08). Multivariable analysis found increased usage hours were predicted best by higher income, higher inspiratory positive airway pressure, and higher bicarbonate. Nonadherence was higher in those with lower income or higher forced vital capacity. In this cohort of adult and pediatric patients with DMD, most individuals were using NIV. While usage hours were higher with lower lung function, substantial variability remains unexplained by examined factors. Nonadherence was observed in some individuals, including those with advanced disease. Further investigations should focus on evaluating patient-oriented outcomes to define optimal NIV usage across the spectrum of disease and determine strategies to counteract issues with nonadherence. Hurvitz MS, Bhattacharjee R, Lesser DJ, Skalsky AJ, Orr JE. Determinants of usage and nonadherence to noninvasive ventilation in children and adults with Duchenne muscular dystrophy. J Clin Sleep Med. 2021;17(10):1973-1980.

Home Noninvasive Ventilation in Pediatric Subjects With Neuromuscular Diseases: One Size Fits All.

Home noninvasive ventilation (NIV) improves disease courses of patients with respiratory insufficiency due to neuromuscular diseases. Data about appropriate ventilator settings for pediatric patients are missing. In this retrospective study, ventilator settings of 128 subjects with neuromuscular disease aged 0-17 y with NIV were compared between 4 age groups (< 1 y, 0-5 y, 6-11 y, and 12-17 y). Additionally, correlations of ventilator settings with age and vital capacity were investigated in an ungrouped approach. Ventilator backup rate decreased significantly with age, leading to significant backup rate differences between all groups except the oldest two. Median (interquartile range) backup rates were 36 (11.5), 24 (4), 20 (4), and 20 (3) breaths/min in groups 1-4, respectively. Median [IQR] expiratory positive airway pressures (4 [0.5], 4 [0], 4 [0], 4 [1] cm H2O, respectively) and median [IQR] inspiratory positive airway pressures (12 [1.5], 12 [5], 12 [2.3], and 14 [4] cm H2O, respectively) showed no significant differences. However, correlation analyses indicated an increase of inspiratory positive airway pressure with age and decreasing FVC, as well as an increase of backup rates with decreasing FVC. Similar NIV settings fit all age groups of pediatric subjects with neuromuscular disease. Thus, we propose an expiratory positive airway pressure of 4-5 cm H2O, an inspiratory pressure delta of 8-10 cm H2O, and an age-oriented backup rate as a starting point for NIV titration. Patients with advanced disease stages might require slightly higher inspiratory positive airway pressures and backup rates.

Noninvasive Ventilation Downloads and Monitoring.

"Home noninvasive ventilation (NIV) is indicated for numerous conditions including neuromuscular disease, thoracic cage disorders, chronic obstructive pulmonary disease, and hypoventilation syndromes. Effective management of patients on home NIV requires clinicians to interpret data downloads from NIV devices. Clinicians must first look at adherence and factors that may impact this including mask comfort and fit. Next, leak assessment is undertaken. Once these are addressed, such information as apnea-hypopnea index, exhaled tidal volume, and percent triggered breaths help clinicians troubleshoot setting changes. Finally, overnight oximetry and transcutaneous CO2 monitoring are useful adjuncts to the data download to optimize NIV settings."

National survey of feasibility of NIV trials for management of children with bronchiolitis

BackgroundBronchiolitis is a major cause of admission to hospital in children. Non-invasive ventilation (NIV) support with continuous positive airway pressure (CPAP) or high-flow nasal cannula (HFNC) oxygen is routinely used...

Risk factors for non-invasive ventilation failure in influenza infection with acute respiratory failure in emergency department.

Non-invasive ventilation (NIV) has been widely used in hypoxemic acute respiratory failure (ARF) due to influenza pneumonia in the emergency department (ED). However, NIV used in influenza-associated acute respiratory failure had a variable rate of failure. Previous studies have reported that prolonged use of NIV was associated with increased mortality. Our study aimed to identify risk factors for NIV failure in influenza infection with acute respiratory failure in ED. We performed a retrospective cohort observational study. Enrolled patients were older than 18years who used NIV due to influenza infection with ARF between 1 January 2017 to 31 December 2018 in Ramathibodi Emergency Department. Patients characteristics, comorbidity, clinical, laboratory outcome, chest imaging, initial NIV setting, and parameters were collected in ED setting. Sequential organ failure assessment (SOFA) score and PaO2/FiO2 (PF) ratio were calculated from the first arterial blood gas in ED. We followed the outcome success or failure of the NIV used. A total of 162 patients were enrolled and 72 (44%) suffered NIV failure in influenza infection with ARF. We used univariate and multivariate logistic analyses to assess risk factors for NIV failure. The ability of risk factor to predict NIV failure was analyzed using the area under the receiver operating characteristic (AUROC). Risk factors of NIV failure included SOFA score (P=0.001), PF ratio (P=0.001) and quadrant infiltrations in chest x-rays (CXR) (P=0.001). SOFA score, PF ratio, and number quadrant infiltrations in chest radiography have good ability to predict NIV failure, AUROC 0.894 (95%CI 0.839-0.948), 0.828 (95%CI 0.764-0.892), and 0.792 (95%CI 0.721-0.863), respectively and no significant difference in the ability to predict NIV failure among three parameters. The use of PF ratio plus number quadrant infiltrations in chest radiography demonstrated a higher predictive ability for NIV failure in influenza infection with ARF. SOFA score, PF ratio, and quadrant infiltrations in chest radiography were good predictors of NIV failure in influenza infection with ARF.

External heated humidification during non-invasive ventilation set up: results from a pilot cross-over clinical trial

Short-term heated humidification has limited effect on physiological and clinical outcomes during non-invasive ventilation set uphttp://bit.ly/31cFfGt

Double-Triggering During Noninvasive Ventilation in a Simulated Lung Model.

Double-triggering is a well-recognized form of patient-ventilator asynchrony in noninvasive ventilation (NIV). This benchtop simulated lung study aimed to determine under which patient and device-specific conditions double-triggering is more prevalent, and how this influences the delivery of NIV. Two commonly used proprietary NIV devices were tested using a benchtop lung model. Lung compliance, airway resistance, respiratory effort, and breathing frequency were manipulated, and the frequency of double-triggering was assessed. A lung model of very low lung compliance (15 mL/cm H2O) was then used to assess the frequency of double-triggering when breathing frequency and respiratory effort were varied, along with basic NIV settings, including inspiratory pressure and expiratory pressure. Minute ventilation and total inspiratory work (as calculated by the simulated lung model) were also correlated with frequency of double-triggering. In both devices, double-triggering was observed with reduced lung compliance (P = .02 and P < .001 for the two devices, respectively). Reduced airway resistance was associated with double-triggering with the one device only (P = .02). Respiratory effort and breathing frequency were not independent predictors of double-triggering across all lung models. In the lung model of very low lung compliance, both devices showed increased double-triggering at a lower breathing frequency (P < .001 and P < .001), higher respiratory effort (P = .03 and P < .001), and greater pressure support (P = .044, P < .001). Importantly, double-triggering was associated with reduced minute ventilation (P = .007) with one device and increased inspiratory work (P < .001) with the other device. Both simulated-patient and device characteristics influenced the frequency of double-triggering in NIV, resulting in meaningful consequences in a simulated lung model.

Noninvasive Ventilation Influenced the Survival of Extreme Super-Super Obese with Obesity Hypoventilation Syndrome

Recent studies conclude noninvasive ventilation (NIV) as a standard first-line therapy for any respiratory failure. The efficacy of NIV in obesity is well defined. In this context, the effectiveness of NIV in extreme super-super obese patients with obesity hypoventilation syndrome is not well studied, and the usage of NIV is controversial because of rare incidence. However, identifying the right patient, right timing, right clinical expertise, correct positions, and right appropriate NIV settings can produce positive results. Therefore, we present a unique case of a 32-year-old male weighing 283 kg, with body mass index >92 kg/m2 and carbon dioxide retention, whose symptoms were worsening despite adequate conventional treatment. He received continuous NIV for 70 h using a standard protocol with close monitoring. There was improvement in the patient vitals and medical condition with significant reduction in arterial carbon dioxide tension, leading to reduction in the length of intensive care unit stay and prevention of further complications. Long-term research is encouraged to validate NIV effectiveness in this group of patients.

Effects of Non-Invasive Ventilation Combined with Oxygen Supplementation on Exercise Performance in COPD Patients with Static Lung Hyperinflation and Exercise-Induced Oxygen Desaturation: A Single Blind, Randomized Cross-Over Trial.

The effects of non-invasive ventilation (NIV) in addition to supplemental oxygen on exercise performance in patients with chronic obstructive pulmonary disease (COPD) with hyperinflation and exercise-induced desaturation (EID) remain unclear. We hypothesized that these patients would benefit from NIV and that this effect would be an add-on to oxygen therapy. Thirteen COPD patients with a residual volume >150% of predicted, normal resting arterial oxygen pressure (PaO2) and carbon-dioxide pressure (PaCO2) and EID during a six-minute walk test were included. Patients performed four constant work-rate treadmill tests, each consisting of two exercise bouts with a recovery period in between, wearing an oronasal mask connected to a ventilator and oxygen supply. The ventilator was set to the following settings in fixed order with clockwise rotation: Sham (continuous positive airway pressure (CPAP) 2 cm H2O, FiO2 21%), oxygen (CPAP 2 cm H2O, FiO2 35%), NIV and oxygen (inspiratory positive airway pressure (IPAP) 14 cm H2O/expiratory positive airway pressure (EPAP) 6 cm H2O, inspired oxygen fraction (FiO2) 35%), intermittent (walking: Sham setting, recovery: NIV and oxygen setting). During the first exercise, bout patients walked further with the oxygen setting compared to the sham setting (225 ± 107 vs 120 ± 50 meters, p < 0.05), but even further with the oxygen/NIV setting (283 ± 128 meters; p < 0.05). Recovery time between two exercise bouts was shortest with NIV and oxygen. COPD patients with severe static hyperinflation and EID benefit significantly from NIV in addition to oxygen during exercise and recovery.