Expiratory Positive Airway Pressure 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.

0617 Efficacy of Nasal Expiratory Positive Airway Pressure in Veterans with Obstructive Sleep Apnea

0617 Efficacy of Nasal Expiratory Positive Airway Pressure in Veterans with Obstructive Sleep Apnea

0609 Improved Sleep Quality with Expiratory Positive Airway Pressure Enhanced Mandibular Advancement Device in OSA

0609 Improved Sleep Quality with Expiratory Positive Airway Pressure Enhanced Mandibular Advancement Device in OSA

Virtual Learning Environment for Respiratory Support: A Simulation-Based Approach to Asynchronous Recognition and Correction of Ventilation Issues

The widespread utilization of medical ventilators, particularly during the COVID-19 pandemic, underscores the critical need for effective training in respiratory care. This paper introduces a web-based e-learning platform designed to simulate the complexities of mechanical ventilation systems, focusing on pressure mode control. The platform incorporates models representing various ventilation types, allowing users to manipulate crucial parameters such as IPAP (Inspiratory Positive Airway Pressure), EPAP (Expiratory Positive Airway Pressure), Ti (Inspiration Time), and BR (Breath Rate). By offering a realistic training environment, this system not only addresses the increasing demand for healthcare professional education but also facilitates effective monitoring and assessment of students’ progress by educators.

How important is the Expiratory Resistance Level in the Expiratory Positive Airway Pressure (EPAP) Mask?

How important is the Expiratory Resistance Level in the Expiratory Positive Airway Pressure (EPAP) Mask?

Efficacy of the ExVent Accessory for the O2Vent Optima Oral Appliance in the Treatment of Obstructive Sleep Apnea

Study Objectives: An optional accessory for the O2Vent Optima mandibular advancement device, the ExVent, provides oral expiratory positive airway pressure (EPAP). Similar to nasal EPAP, oral EPAP results in passive airway dilatation, reducing flow limitation. The present study was conducted to evaluate the safety and efficacy of the ExVent accessory for the treatment of mild to moderate obstructive sleep apnea (OSA). Methods: This prospective, multicenter, open-label, single-arm study enrolled participants diagnosed with mild to moderate OSA (defined as apnea–hypopnea index [AHI] 5–29). During the Home Use Phase, study participants logged their hours of O2Vent Optima + ExVent usage at home over 3 months. Participants were then evaluated by in-laboratory polysomnogram while using the O2Vent Optima + ExVent. The primary effectiveness measure was a change in AHI relative to baseline while using the O2Vent Optima + ExVent. Results: Treatment with the O2Vent Optima + ExVent improved AHI by 62% on average, from 15.3 (interquartile range [IQR]: 11.5–19.5) to 5.8 (IQR: 3.9–6.8; p&lt;0.001). Mean oxygen saturation improved from 93.5%±1.2% to 94.6%±1.34% (p=0.006). The lowest oxygen saturation increased from 85% (IQR: 83%–87%) to 90% (IQR: 89%–95; p&lt;0.001). The overall treatment success rate (AHI&lt;5) was 66%, and the treatment response rate (&gt;50% reduction in AHI) was 77%. No excessive adverse events or device malfunction events were reported. Conclusions: Use of the O2Vent Optima with the ExVent oral EPAP accessory successfully reduced AHI in mild to moderate OSA with no significant adverse effects.

Treatments for obstructive sleep apnea: CPAP and beyond.

Treatment options for obstructive sleep apnea include positive airway pressure and alternatives such as behavioral interventions, oral appliances, nasal expiratory positive airway pressure, negative pressure interventions, and surgical procedures. Certain drugs are also promising. An important aspect of the treatment includes troubleshooting the reasons for poor adherence to positive airway pressure treatment, discussing alternatives based either on individual preference or on phenotypic characterization of the sleep apnea, and managing expectations.

P070 Efficacy of the ExVent Accessory with the O2Vent Optima Oral Appliance in the Treatment of Obstructive Sleep Apnea – A Clinical Trial

Abstract Introduction The study assessed the efficacy of oral appliance device O2Vent Optima and ExVent, an oral Expiratory Positive Airway Pressure (EPAP) accessory in the treatment of OSA. Methods A prospective, open-label study conducted at 3 sites in mild to moderate OSA (AHI ≥ 5 and ≤ 30). Screening Phase A diagnostic in-lab PSG study confirmed a diagnosis of mild to moderate OSA. Treatment I Subjects used O2Vent Optima for 6 weeks and underwent a PSG sleep night while using the O2Vent Optima. Treatment II Subjects used O2Vent Optima + ExVent for 6 weeks and underwent a PSG sleep night while using the O2Vent Optima + ExVent Primary Effectiveness Measure: Change in AHI between baseline vs. O2Vent Optima MAD vs. O2Vent Optima + ExVent Results Treatment with Optima, Optima + ExVent reduced AHI from 22.5±6.4/hr to 12.6±4.5/hr to 5.9±2.7 (p&amp;lt; 0.005 baseline vs. Optima and Optima + ExVent; p&amp;lt;0.05 Optima MAD vs. Optima + ExVent). Average reduction in AHI with Optima was 43% and with Optima + ExVent was 72%. The lowest oxygen during sleep increased from 84.6±2.7% to 88.6±2.9% to 91.6±3.2% (p&amp;lt; 0.005 baseline vs. Optima and Optima + ExVent; p&amp;lt;0.05 Optima vs. Optima + ExVent). During the trial patients on treatment with Optima and Optima + ExVent demonstrated no excessive adverse events or device malfunction. Conclusion Treatment with O2Vent Optima and O2Vent Optima + ExVent significantly improved OSA compared to the baseline. Even greater benefit was observed with addition of ExVent to the Optima in mild to moderate OSA.

Noninvasive Ventilation or CPAP for Postextubation Support in Small Infants.

Infants with a high risk of extubation failure are often treated with noninvasive ventilation (NIV) or CPAP, but data on the role of these support modalities following extubation are sparse. This report describes our experience using NIV or CPAP to support infants following extubation in our pediatric ICUs (PICUs). We performed a retrospective study of children < 10 kg receiving postextubation NIV or CPAP in our PICUs. Data on demographics, medical history, type of support, vital signs, pulse oximetry, near-infrared spectroscopy (NIRS), gas exchange, support settings, and re-intubation were extracted from the electronic medical record. Support was classified as prophylactic if planned before extubation and rescue if initiated within 24 h of extubation. We compared successfully extubated and re-intubated subjects using chi-square test for categorical variables and Mann-Whitney test for continuous variables. We studied 51 subjects, median age 44 (interquartile range 0.5-242) d and weight 3.7 (3-4.9) kg. There were no demographic differences between groups, except those re-intubated were more likely to have had cardiac surgery prior to admission (0% vs 14%, P = .040). NIV was used in 31 (61%) and CPAP in 20 (39%) subjects. Prophylactic support was initiated in 25 subjects (49%), whereas rescue support was needed in 26 subjects (51%). Twenty-two subjects (43%) required re-intubation. Re-intubation rate was higher for rescue support (58% vs 28%, P = .032). Subjects with a pH < 7.35 (4.3% vs 42.0%, P = .003) and lower somatic NIRS (39 [24-56] vs 62 [46-72], P = .02) were more likely to be re-intubated. The inspiratory positive airway pressure, expiratory positive airway pressure, and FIO2 were higher in subjects who required re-intubation. NIV or CPAP use was associated with a re-intubation rate of 43% in a heterogeneous sample of high-risk infants. Acidosis, cardiac surgery, higher FIO2 , lower somatic NIRS, higher support settings, and application of rescue support were associated with the need for re-intubation.

Profiles of Elderly Patients with Obesity Hypoventilation Syndrome in Martinique: A Single-Center Study.

Obesity hypoventilation syndrome (OHS) is a form of chronic respiratory insufficiency related to obesity that affects young and old people. Age appears to be associated with poorer response to treatment by nighttime ventilation. This study aimed to describe the characteristics of elderly subjects (>65 years) with OHS compared to younger patients, with a view to adapting therapy in older individuals. We conducted a retrospective study comparing socio-demographic, clinical, functional characteristics as well as treatment and outcomes between young (<65 years) and older (65 years and older) individuals with OHS at the University Hospital of Martinique. We included 143 patients (114 women), of whom 82 were 65 years or older (57%). Charlson index was higher in the older group. Patients in ≥65 years group were less frequently obese, but more frequently had diabetes mellitus, cardiac arrythmia and arterial hypertension compared to younger patients. There was no difference in the circumstances of diagnosis or arterial blood gas at diagnosis. At follow up, partial pressure of carbon dioxide (pCO2) was higher in ≥65 years group. Despite comparable NIV settings, apart from lower expiratory positive airway pressure (EPAP) with higher apnea-hypopnea index (AHI), patients in the ≥65-year-old group remained more frequently hypercapnic. In conclusion, over half (57%) of patients with OHS in our cohort were aged over 65 years. Older patients developed OHS at lower BMI levels than their younger counterparts, and more frequently, had comorbidities such as diabetes, hypertension and cardiac arrhythmia. Increased Charlson index, lower BMI and female sex were independent factors associated with OHS in the elderly.

0570 Use of the ExVent Accessory with the O2Vent Optima Oral Appliance for the Treatment of Obstructive Sleep Apnea – A Clinical Trial

Abstract Introduction The ExVent is an optional accessory to the O2Vent Optima mandibular advancement device (MAD) and provides oral Expiratory Positive Airway Pressure (EPAP). Oral EPAP with the ExVent is designed to provide upper airway support via similar mechanisms of action of nasal EPAP devices in commercial distribution, e.g., passive dilatation of the airway, which reduces flow limitation. Nasal EPAP devices are in commercial distribution as stand-alone therapies for the treatment of OSA. The oral EPAP provided by the ExVent accessory is designed to augment the OSA therapy provided by the O2Vent Optima. Methods This is a prospective, open-label, single-arm study conducted at 3 sites. Subjects who have been diagnosed with mild to moderate OSA (i.e., AHI ≥ 5 and ≤ 30) were included. Screening Phase The subjects completed a PSG study to obtain the baseline AHI and confirm a diagnosis of mild to moderate OSA Home Use Phase Subjects used the O2Vent Optima + ExVent for up to 3 months and logged usage hours. Subsequent to the Home Use Phase subjects underwent an in-lab PSG sleep night while using the O2Vent Optima + ExVent. Primary Effectiveness Outcome Measure: Change in AHI between baseline and the AHI measured during the in-lab PSG sleep night using O2Vent Optima + ExVent. Safety Outcome Measure: Adverse events will be summarized descriptively in terms of type and frequency Results Patients with mild to moderate OSA were treated with Optima MAD and ExVent for 3 months at 3 different sites in North America. Preliminary data analysis demonstrated that treatment with Optima MAD and ExVent reduced AHI from 13.5±6.4/hr to 6.6±4.5/hr (p&amp;lt; 0.05), average 58% reduction in AHI. The lowest oxygen during sleep increased from 84.6±2.7% to 88.6±2.9% (p&amp;lt; 0.05). Overall success rate (&amp;gt;50% reduction in AHI) with treatment was 80%. During the trial patients on treatment with Optima MAD and ExVent demonstrated no excessive adverse events or device malfunction. Conclusion The clinical trial confirmed successful treatment with combined use of O2Vent Optima MAD and oral Expiratory Positive Airway Pressure accessory - ExVent in patients with mild to moderate OSA. Treatment was well tolerated with no excessive adverse effects. Support (if any)

0953 A Novel Active Humidifier for Non-Invasive Ventilated Patients

Abstract Introduction The RespirAq® humidifier is a novel, active heated humidifier that humidifies without the need for additional water. Within milliseconds, the humidifier switches between a super-hydrophilic state to capture moisture during expiration, and a super-hydrophobic state, returning moisture during inspiration. The device delivers gases at 37°C/100% relative humidity to individuals requiring humidification, including those with tracheostomies. We demonstrated the device meets EN ISO 80601 2 74:2020 during bench testing. This study aimed to compare the performance of the novel humidifier with a heated humidifier - HH (MR850™ Fisher &amp; Paykel Healthcare) and a heat and moisture exchanger - HME (DAR™ Covidien) in healthy volunteers during non-invasive ventilation (NIV) using a non-vented full face mask. Methods Ten healthy volunteers were recruited. NIV was performed at different settings (inspiratory positive airway pressure (IPAP) range 5-20cmH20, expiratory positive airway pressure (EPAP) = 5cmH20) over a one-hour period. Humidity and temperature were collected continuously during the study. Results Sixty per cent of participants were female. Mean age of 35.6 ± 5.89 years (M±SD, n=10). Absolute humidity inside the face mask increased from 22.55 ± 2.41 mg/L without humidification to 30.18 ± 2.07 mg/L with an HME, and 39.09 ± 1.05 mg/L and 38.23 ± 1.78 mg/L when using a water-based heated humidifier and the novel humidifier, respectively. When comparing the performance of the humidification devices head-to-head, the two heated humidifiers significantly outperformed the HME (HME vs Novel = P &amp;lt; 0.0001, HME vs HH = p &amp;lt; 0.0001) and there was no significant difference seen between the two active humidifiers (p =0.2047). Conclusion Results show that the device meets the 12 mg/L absolute humidity established by the EN ISO 80601-2-74:2020 standards and that there is no significant difference in performance compared to traditional heated humidification. This suggests that the novel device can deliver the performance of a heater humidifier at the size, reliability and ease of use of a heat and moisture exchanger. Due to the mechanism of action, droplet/aerosol transmission of COVID-19 may also be mitigated. Further studies are warranted to confirm these findings. Support (if any) This research was supported by Tier 2 KiwiNet funding.

Stepwise Add-on and Endotype-informed Targeted Combination Therapy to Treat Obstructive Sleep Apnea: A Proof-of-Concept Study.

Oral appliance therapy (OAT) is an effective treatment for many people with obstructive sleep apnea (OSA). However, OSA pathogenesis is heterogenous and in ~50% of cases, OAT does not fully control OSA. This study aimed to control OSA in individuals with an incomplete response to OAT alone by using additional targeted therapies informed by OSA endotype characterization. Twenty-three people with OSA (apnea-hypopnea index (AHI): 41+19 events/h) not fully resolved (AHI>10 events/h) with oral appliance therapy alone were prospectively recruited. OSA endotypes were characterized pre-therapy during a detailed physiology study night. Initially, an expiratory positive airway pressure valve (EPAP) and supine-avoidance device therapy were added to target the impaired anatomical endotype. Those with residual OSA (AHI>10 events/h) then received one or more non-anatomical interventions based on endotype characterization. This included O2 (4L/min) to reduce high loop gain (unstable respiratory control) and 80/5mg atomoxetine-oxybutynin to increase pharyngeal muscle activity. Finally, if required, OAT was combined with EPAP and CPAP therapy. Twenty participants completed the study. OSA was successfully controlled (AHI<10 events/h) with combination therapy in all but one participant (17/20 without CPAP). OAT plus EPAP and supine-avoidance therapy treated OSA in 10 (50%) participants. OSA was controlled in five (25%) participants with the addition of O2 therapy, one with atomoxetine-oxybutynin and one required O2 plus atomoxetine-oxybutynin. Two participants required CPAP for their OSA, another was CPAP intolerant. These novel prospective findings highlight the potential of precision medicine to inform targeted combination therapy to treat OSA. Clinical trial registered with Australian New Zealand Clinical Trials Registry (ACTRN12618001995268).

Decannulation in congenital central hypoventilation syndrome.

Patients with congenital central hypoventilation syndrome (CCHS) require long-term ventilation to ensure gas exchange and to prevent deleterious consequences for neurocognitive development. Two ventilation modes may be used for these patients depending on their tolerance, one invasive by tracheostomy and the other noninvasive (NIV). For patients who have undergone a tracheostomy, transition to NIV is possible when they meet predefined criteria. Identifying the conditions favorable for weaning from a tracheostomy is critical for the success of the process. The aim of the study was to share our experience of decannulation in a reference center; we hereby describe the modality of ventilation and its effect on nocturnal gas exchange before and after tracheostomy removal. Retrospective observational study at Robert Debré Hospital over the past 10 years. The modalities of decannulation and transcutaneous carbon dioxide recordings or polysomnographies before and after decannulation were collected. Sixteen patients underwent decannulation following a specific procedure for transition from invasive to NIV. All decannulations were successful. The median age at decannulation was 12.6 [9.4; 14.1] years. Nocturnal gas exchange was not significantly different before and after decannulation, while expiratory positive airway pressure and inspiratory time increased significantly. An oronasal interface was chosen in two out of three patients. The median duration of hospital stay for decannulation was 4.0 [3.8; 6.0] days. Our study underlines that decannulation and transition to NIV are achievable in CCHS children using a well-defined procedure. Patient preparation is crucial to the success of the process.

Effect of switching from continuous to bilevel positive airway pressure on sleep quality in patients with obstructive sleep apnea: the prospective POP IN VAuto study.

Issues with tolerability and side effects can decrease continuous positive airway pressure (CPAP) device usage and the benefits of therapy. Different positive airway pressure (PAP) therapy modes providing expiratory pressure relief or using a different pressure during inspiration vs. expiration (bilevel PAP) may alleviate some of these issues. This multicenter, prospective study evaluated the effects of switching from CPAP to bilevel PAP (VAuto mode) on respiratory parameters, device usage, side effects and patient-reported outcomes in patients with obstructive sleep apnea (OSA). Eligible OSA patients had started CPAP ≥3 months previously, had good compliance (mean 6.1±2.0 h/night) and well-controlled OSA [residual apnea-hypopnea index (AHI) 4.9±3.1/h] but had pressure tolerance issues or persistent side effects/discomfort. All were switched from CPAP to bilevel PAP (AirCurve 10 VAuto; ResMed). Effectiveness (residual AHI), sleep quality, daytime sleepiness, fatigue, therapy-related side effects, and patient satisfaction/preference were assessed after 3 months and 1 year. Forty patients were analyzed (68% male, age 64±11 years, body mass index 30.7±5.8 kg/m2). At 3 months and 1 year after switching to bilevel PAP, median [interquartile range] residual AHI was 4/h [2-5.3] and 3.7/h [1.8-5], respectively, and device usage was 7.0 [4.9-7.5] and 6.4 [4.4-7.3] h/night, respectively. Device switch was associated with significant reductions from baseline in expiratory PAP {from 12 [11-13] to 8 [7-9] cmH2O at 3 months (P<0.001) and 9 [8-12] cmH2O at 1 year (P=0.005)}, 95th percentile pressure {from 14 [12-14] to 10 [9-11] and 10 [8-11] cmH2O; P<0.001 and P=0.001, respectively} and leak {from 1 [0-6] to 0 [0-1] and 0 [0-2] L/min; P=0.049 and P=0.033, respectively}. The Pittsburgh Sleep Quality Index score decreased significantly from baseline to 3 and 6 months [7.2±4.0 to 5.0±3.2 (P=0.005) and 4.5±2.7 (P<0.001), respectively]. CPAP-related mouth dryness, choking sensation and aerophagia were significantly improved one year after switching to bilevel PAP. Bilevel PAP was preferred over CPAP by 90% of patients. Switching to bilevel PAP had several benefits in patients struggling with CPAP, facilitating therapy acceptance and ongoing device usage.

I-EPAP Device in COPD With Dynamic Hyperinflation: Effects on Maximal Exercise Tolerance and Physiological Adjustments

Dynamic lung hyperinflation is an important cause of morbidity and mortality in patients with COPD.[1][1] Indeed, the use of expiratory positive airway pressure (EPAP) at rest causes acute lung deflation in COPD.[2][2] However, its application has led to a progressive reduction in exercise tolerance

P004 Addition of an oral expiratory positive pressure valve (EPAP) to an oral appliance therapy device can resolve obstructive sleep aponea (OSA)

Abstract Background Mandibular advancement splints (MAS) provide effective therapy for many people with OSA. However, in ~50% of cases, MAS alone does not fully resolve OSA. A single-night study showed that ~45% of people with incompletely treated OSA with MAS alone had resolution (apnoea-hypopnea index [AHI]&amp;lt;10 events/h) with the addition of an oral expiratory positive airway pressure (EPAP) valve. This study aimed to determine the safety, tolerability, and longer-term efficacy of oral EPAP valve plus MAS in incomplete responders to MAS alone. Methods Seven people with OSA (AHI=26±13events/h) not fully resolved with MAS alone (AHI&amp;gt;10events/h) were recruited. In-laboratory polysomnography with MAS plus oral EPAP was performed on night 1. Participants then used MAS+EPAP at home for 30-days and completed weekly questionnaires to assess safety, tolerability, and next-morning sleepiness (Karolinska sleepiness scale, KSS). Impact on daytime sleepiness (Epworth sleepiness scale, ESS) was assessed at night 1 and 30. A final at-home WatchPAT study was performed at night 30. Results OSA was successfully treated (AHI&amp;lt;10events/h) in 4/7 participants during the night 1 in-laboratory study (MAS alone vs. MAS+ EPAP 13±2 vs. 7±2events/h). Five had treatment success by night 30 (6±3events/h). Daytime sleepiness (ESS) did not change after 30 days of MAS+EPAP although next-morning sleepiness tended to reduce ( KSS 4.4±1.9 vs. 3.3±1.5, p=0.047 n=7). Oral EPAP was generally well-tolerated with no major side effects reported. Discussion Oral EPAP may be an effective treatment addition for some people with OSA who have an incomplete therapeutic response to MAS alone.

Prediction of Noninvasive Ventilation Failure in COVID-19 Patients: When Shall We Stop?

In coronavirus disease 2019 (COVID-19), there are no tools available for the difficult task of recognizing which patients do not benefit from maintaining respiratory support, such as noninvasive ventilation (NIV). Identifying treatment failure is crucial to provide the best possible care and optimizing resources. Therefore, this study aimed to build a model that predicts NIV failure in patients who did not progress to invasive mechanical ventilation (IMV). This retrospective observational study included critical COVID-19 patients treated with NIV who did not progress to IMV. Patients were admitted to a Portuguese tertiary hospital between October 1, 2020, and March 31, 2021. The outcome of interest was NIV failure, defined as COVID-19-related in-hospital death. A binary logistic regression was performed, where the outcome (mortality) was the dependent variable. Using the independent variables of the logistic regression a decision-tree classification model was implemented. The study sample, composed of 103 patients, had a mean age of 66.3 years (SD=14.9), of which 38.8% (40 patients) were female. Most patients (82.5%) were autonomous for basic activities of daily living. The prediction model was statistically significant with an area under the curve of 0.994 and a precision of 0.950. Higher age, a higher number of days with increases in the fraction of inspired oxygen (FiO2), a higher number of days of maximum expiratory positive airway pressure, a lower number of days on NIV, and a lower number of days from disease onset to hospital admission were, with statistical significance, associated with increased odds of death. A decision-tree classification model was then obtained to achieve the best combination of variables to predict the outcome of interest. This study presents a model to predict death in COVID-19 patients treated with NIV in patients who did not progress to IMV, based on easily applicable variables that mainly reflect patients' evolution during hospitalization. Along with the decision-tree classification model, these original findings may help clinicians define the best therapeutical approach to each patient, prioritizing life-comforting measures when adequate, and optimizing resources, which is crucial within limited or overloaded healthcare systems. Further research is needed on this subject of treatment failure, not only to understand if these results are reproducible but also, in a broader sense, helping to fill this gap in modern medicine guidelines.

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.

Comparison of High Intensity Non-Invasive Ventilation With Low Intensity Non-Invasive Ventilation In Patients With Acute Copd Exacerbation

Objective: To determine the outcome of high intensity non-invasive positive pressure ventilation (HI-NPPV) as compared to low intensity non-invasive positive pressure ventilation (LI-NPPV) in patients with acute COPD exacerbations. Methodology: This Randomized controlled trial Department of PulmonologyFauji Foundation Hospital Rawalpindi from  31st December 2016 to 30thJune 2017. Arterial blood gases will be taken at admission. If values of pH and paCO2 meet the criteria for non-invasive ventilation then patients will be enrolled in the study. Patients will be randomly divided into two groups by lottery method. GROUP A and GROUP B. GROUP A will receive high intensity NIV (HI-NPPV) and GROUP B will receive low intensity NIV (LI-NPPV) by TRIOLOGY machine. Expiratory positive airway pressure (EPAP) will remain between 4 to 6 cmH2O. Arterial blood gases (ABGs) will be done at baseline and then 72 hours after admission. Improvement in PaCO2, HCO3, and FEV1 will be recorded 72 hours from baseline and collected on proforma (attached). Results: Mean age (years) in the study was 55.54+3.81. There were 08 male patients included the study meeting the inclusion criteria. Of these, 05 and 03 male patients among both the groups respectively. Similarly, there were 92 female patients included the study meeting the inclusion criteria, of these, 45 and 47 female patients among both the groups respectively. Outcome of the study was assessed in terms of mean PaCO2 (mmHg), HCO3 (mmol/L) and FEV1 at baseline and after 72 hours. Mean PaCO2, HCO3 and FEV1 at baseline was 64.87+5.22, 33.75+4.17 and 0.66+0.04 respectively. After 72 hours, mean PaCO2 (mmHg) , HCO3(mmol/L), and FEV1 among both the groups was 63.98+6.58 vs 41.46+2.40, 33.10+4.81 vs 23.12+2.01, 0.66+0.05 vs 0.72+0.04 with following P value of (0,000, 0.000, 0.000) respectively. Conclusion: High intensity non-invasive positive pressure ventilation (HI-NPPV) has no different outcome as compared to low intensity non-invasive positive pressure ventilation (LI-NPPV) in patients with acute COPD exacerbations.