Titration Of Noninvasive Ventilation Research Articles

P005 A two-night randomised controlled cross-over trial of AVAPS AE auto-titrating bi-level ventilation vs standard in-lab titration in patients with motor neurone disease commencing overnight ventilatory support

Abstract Introduction Sleep disordered breathing in motor neurone disease (MND) is heterogeneous. Auto-adjusting AVAPS-AE mode of non-invasive ventilation (NIV) could simplify NIV setup and use in MND. This pilot study assessed NIV titration and longer-term outcomes with AVAPS AE auto-pressure support versus standard S/T mode NIV titration in patients with MND. Methods 10 MND patients commencing NIV consented to a 2 consecutive night randomised controlled cross-over trial of auto-titrating AVAPS-AE versus standard S/T mode NIV titrated according to current clinical practice. Patients underwent in-laboratory polysomnography (PSG) on both nights before continuing on the second allocated mode of NIV. Results 8 patients completed both cross-over nights and 9 subsequently continued on home NIV (4 on S/T and 5 on AVAPS-AE mode). Compared to baseline, both S/T and AVAPS-AE modes significantly reduced apnea hypopnea index (AHI; mean [95%CI] 14.8 [6.8-22.8] to 1.2 [0-2.7] and 3.6 [0-7.1] /h respectively), with no significant differences between modes on other PSG outcomes. Maximum EPAP (15.4 [13.4-17.4] vs 8.3 [4.9-11.6] cmH2O, p=0.003) and pressure support levels (16.3 [11.2-21.3] vs 6.6 [5.9-7.4] cmH2O, p=0.003) were higher with AVAPS-AE versus S/T mode respectively, although average pressure support levels were not different. Over 6 months of follow-up, average daily use was similar in both treatment groups (AVAPS-AE 7.3 [3.2-11.3]; S/T mode 7.8 [3.5-12] h/day). Conclusion Automated AVAPS-AE mode of BiPAP support appears to achieve similar control of sleep disordered breathing when compared to standard S/T mode, and to be well tolerated and used in patients with MND.

P020 Polysomnographic titration of non-invasive ventilation in motor neurone disease (3TLA): Study protocol for a randomised controlled trial

Abstract Introduction The benefits of using non-invasive ventilation (NIV) on survival in motor neurone disease (MND) are well-established. Recent MND cohort studies have extended this finding to suggest that adherence with NIV of >4 hours/day improves survival more than <4 hours/day, and that any use increases survival more than no use at all. Despite these data, only approximately 19% of Australians with MND start NIV. Our team has recently demonstrated that specific and individualised NIV titration using polysomnography (PSG) leads to better NIV usage in MND. However, for this clinical practice model to result in sustained benefits, evidence of effectiveness across multiple sites, as well as culture and practice change must occur. The primary aim of this randomised controlled trial (RCT) is to determine if the proportion of participants using NIV for >4 hours/day during the 7-week post-randomisation period is higher in the PSG (Intervention) than the Control group. Methods A two-arm, individual participant, assessor-blinded RCT in 7 MND care centres across Australia. Eligible participants will be randomised (1:1) to either the Intervention (PSG assisted optimization of NIV) or a Control group (sham PSG). Respiratory, sleep and patient-reported outcome measures will be collected at baseline and follow-up 7 weeks after the PSG. An implementation science program, health economic evaluation and 12-month cohort follow-up will be undertaken. Data collection is underway. Trial Registration ClinicalTrials.gov (#CT05136222).

Transcutaneous CO2 monitoring as indication for inpatient non-invasive ventilation initiation in patients with amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is characterized by profound muscle weakness, including diaphragmatic weakness resulting in hypercapnic respiratory failure. While non-invasive ventilation (NIV) is usually initiated in the home, patients presenting with hypercapnic respiratory failure may be at high risk of adverse outcomes with delays in treatment. We aim to describe the clinical utility of transcutaneous CO2 (TCO2 ) to assess the need for inpatient initiation of NIV. Eight patients from the University of Michigan Pranger ALS clinic were directly admitted to the hospital for urgent initiation of NIV between May 2020-May 2021. A retrospective review of electronic medical records, including pre-hospital pulmonary function assessments, hospitalization blood gases, and NIV use metrics was performed. All eight patients had symptoms of respiratory insufficiency at time of admission, although not all patients had forced vital capacity (FVC) measurements that would identify need for NIV. All patients had measured TCO2 > 45 mmHg. Seven of eight patients had worsening hypercapnia after admission, indicating advanced respiratory failure. All patients were titrated to tolerance of continuous nocturnal NIV while in the hospital, with an average length of stay of 6.5 days (range, 3-8). All patients demonstrated compliance with NIV, >4h, at post-hospital follow-up. Many current ambulatory measurements underestimate, or incompletely evaluate, respiratory dysfunction, and arterial blood gases are not typically readily available. Outpatient TCO2 measurements can serve as a useful screening tool to identify ALS patients who would benefit from inpatient initiation and titration of NIV.

Average volume-assured pressure support vs conventional bilevel pressure support in pediatric nocturnal hypoventilation: a case series.

Average volume-assured pressure support (AVAPS) is a modality of noninvasive ventilation that provides a targeted tidal volume by automatically adjusting the inspiratory pressure support within a set range. Pediatric studies evaluating the efficacy of AVAPS in treating nocturnal hypoventilation are confined to case reports. The aim of this study was to compare AVAPS to conventional bilevel positive airway pressure (BPAP) support in improving hypercarbia in a cohort of pediatric patients with nocturnal hypoventilation. Retrospective review of patient records at an established tertiary pediatric sleep laboratory over a 6-year period. Ventilatory and sleep study parameters from AVAPS and conventional BPAP titration studies were compared. AVAPS was used only if hypoventilation was not controlled using conventional BPAP. Inspiratory pressures, tidal volumes, and adherence were downloaded on final titrated ventilatory settings. Comparisons were made using paired t test. A total of 19 patients (11 boys, 8 girls; median age 10.5 years, range 1 to 20 years) were identified. Diagnoses included neuromuscular disease (n = 9), obstructive hypoventilation (n = 5), parenchymal lung disease (n = 4), and congenital central hypoventilation syndrome (n = 2). AVAPS demonstrated significant improvement in peak (P = .009) and mean (P = .001). Transcutaneous CO₂ parameters compared to conventional bilevel. Oxygenation on AVAPS showed positive trend but did not reach statistical significance. AVAPS delivered higher tidal volumes (P = .04) using similar pressures. There was no statistically significant difference in obstructive apnea-hypopnea index, respiratory arousal index, sleep efficiency, and adherence between AVAPS and conventional BPAP. AVAPS was an effective alternative to conventional BPAP in improving hypercarbia in our selective cohort of pediatric patients. Prospective, longitudinal studies are needed to evaluate the benefits of AVAPS feature in the pediatric population.

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.

Automatic EPAP intelligent volume-assured pressure support is effective in patients with chronic respiratory failure: A randomized trial.

Patients with chronic respiratory failure are increasingly managed with domiciliary non-invasive ventilation (NIV). There may be limited ability to provide NIV titration for these complex patients, and ventilatory requirements and upper airway support needs may change over time. Therefore, an automatically adjusting expiratory positive airway pressure (AutoEPAP) algorithm may offer advantages over manually adjusted EPAP for treating these patients. This study compared 4% oxygen desaturation index (ODI4%) values during the use of an AutoEPAP algorithm versus manual EPAP titration with the intelligent volume-assured pressure support (iVAPS) algorithm. This prospective, single-blind, randomized, crossover study was conducted at six US sites. Patients with chronic respiratory failure (neuromuscular disease, chronic obstructive pulmonary disease, obesity hypoventilation and other aetiologies) and an apnoea-hypopnoea index of >5/h who were already established NIV users underwent a single night of NIV with the iVAPS manual EPAP and iVAPS AutoEPAP in the sleep laboratory in random order. A total of 38 patients constituted the study population. Mean ODI4% was statistically non-inferior with AutoEPAP versus manual EPAP (P < 0.0001). There was no difference in the effect on ODI4% across respiratory failure subgroups. Ventilation parameters and gas exchange were similar with either NIV mode, indicating equally effective treatment of respiratory failure. Sleep parameters were improved during AutoEPAP versus manual EPAP. A single night of NIV using the iVAPS with AutoEPAP algorithm was non-inferior to a single night of iVAPS with manual EPAP titration in patients with respiratory failure. NCT02683772 at clinicaltrials.gov.

Randomized cross-over trial of ventilator modes during non-invasive ventilation titration in amyotrophic lateral sclerosis.

Non-invasive ventilation (NIV) improves survival, quality of life and sleep in patients with amyotrophic lateral sclerosis (ALS). Nevertheless, NIV titration is conducted in different ways. We aim to provide more insight into NIV titration by comparing the effects of a spontaneous (S) and spontaneous-timed (ST) modes on gas exchange, sleep architecture and patient-ventilator asynchronies (PVAs). After an initial night of NIV titration, patients were randomized to S or ST mode in a cross-over design. NIV was titrated using polysomnography, oximetry (oxygen saturation, SpO2 %) and transcutaneous carbon dioxide (PtcCO2 ) measurement. PVAs were analysed breath-by-breath. Thirteen patients were analysed after inclusion. ST mode showed better results in gas exchange (minimal SpO2 %: 83 (80-89)% vs 87 (84-89)%; oxygen desaturation index: 15 (5-28)/h sleep vs 7 (3-9)/h sleep; PtcCO2 >55 mm Hg: 20 (0-59)% vs 0 (0-27)% total sleep time for S and ST mode, respectively, all P < 0.05) and respiratory events (obstructive: 8.9 (1.2-18.3)/h sleep vs 1.8 (0.3-4.9)/h sleep and central: 2.6 (0.4-14.1)/h sleep vs 0.2 (0.0-1.1)/h sleep for S and ST mode, respectively, both P < 0.01). No differences in sleep architecture were found. Ineffective efforts and respiratory events were more frequently present in S mode. Nevertheless, four patients were discharged on S mode as these patients showed clinically better results for sleep architecture and PVA during the night on S mode. ST mode shows better results in gas exchange, respiratory events and PVA. Nevertheless, accurate NIV titration remains necessary as some patients show equal or better results when using the S mode.

Patient-ventilator asynchrony, leaks and sleep in patients with amyotrophic lateral sclerosis

Sleeping with non-invasive ventilation (NIV) in amyotrophic lateral sclerosis appears to be accompanied by a high patient-ventilator asynchrony (PVA) index. This prospective observational cohort study quantifies PVA and leaks, and searches for effects of these events on sleep after polysomnographic NIV titration. Full-video polysomnography, with incorporation of transcutaneous carbon dioxide and ventilator software, was used to analyse sleep epoch-by-epoch and respiratory events and PVA breath-by-breath in 35 patients (17 non-bulbar). After diagnostic polysomnography, NIV was titrated during three consecutive nights. Sleep, PVA and leaks were evaluated at discharge and after one month. Results showed that non-bulbar patients improved in sleep architecture and oxygen and carbon dioxide levels while bulbar patients only improved oxygen saturation. PVA remained present at discharge (non-bulbar 54 (21–101) and bulbar 31 (9–39)/h sleep) and one month (non-bulbar 31 (9–39) and bulbar 32 (17–55)/h sleep), with ineffective effort as most prominent asynchrony. Leaks also persisted after titration (non-bulbar 16.6 (3.1–44.6) and bulbar 5.1 (0.0–19.5)% of total sleep time (TST)) and one month (non-bulbar 7.7 (1.4–29.3) and bulbar 12.7 (0.0–35.2)% TST). PVA and leaks have none to minor effect on sleep architecture. In conclusion, although PVA and leaks remain present after meticulous NIV titration, these events seem not to interfere with sleep.

Noninvasive Ventilation Improves Sleep in Amyotrophic Lateral Sclerosis: A Prospective Polysomnographic Study

To evaluate the effects of noninvasive ventilation (NIV) on sleep in patients with amyotrophic lateral sclerosis (ALS) after meticulous titration with polysomnography (PSG). In this prospective observational study, 24 ALS patients were admitted to the sleep laboratory during 4 nights for in-hospital NIV titration with PSG and nocturnal capnography. Questionnaires were used to assess subjective sleep quality and quality of life (QoL). Patients were readmitted after one month. In the total group, slow wave sleep and REM sleep increased and the arousal-awakening index improved. The group without bulbar involvement (non-bulbar) showed the same improvements, together with an increase in sleep efficiency. Nocturnal oxygen and carbon dioxide levels improved in the total and non-bulbar group. Except for oxygen saturation during REM sleep, no improvement in respiratory function or sleep structure was found in bulbar patients. However, these patients showed less room for improvement. Patient-reported outcomes showed improvement in sleep quality and QoL for the total and non-bulbar group, while bulbar patients only reported improvements in very few subscores. This study shows an improvement of sleep architecture, carbon dioxide, and nocturnal oxygen saturation at the end of NIV titration and after one month of NIV in ALS patients. More studies are needed to identify the appropriate time to start NIV in bulbar patients. Our results suggest that accurate titration of NIV by PSG improves sleep quality. A commentary on this article appears in this issue on page 511.

Noninvasive ventilation: Are we overdoing it?

Background:Use of noninvasive ventilation (NIV) outside guideline recommendations is common. We audited use of NIV in our tertiary care critical care unit (CCU) to evaluate appropriateness of use and patient outcomes when used outside level I recommendations.Materials and Methods:Prospective observational study of all patients requiring NIV. Clinical parameters and arterial blood gases were recorded at initiation of NIV and 2 h later (or earlier if clinically warranted). NIV titration and decision to intubate were left to the discretion of treating intensivist. Patients were categorized into two groups: Group 1: Those with level I indications for use of NIV and group 2: All other levels of indications. Patients were followed until hospital discharge.Results:From January 2010 to June 2010, 1120 patients were admitted to the CCU. Of these 106 patients required NIV support with 40.6% (n = 43/106) being in group 1 and 59.4% (n = 63/106) in group 2. Of these 35.8% patients (38/106) failed NIV and required endotracheal intubation. NIV failure rates (41.27% vs. 27.91%; P = 0.02) and mortality (30.6% vs. 18.6%; P = 0.03) were significantly higher in group 2 patients. In a logistic regression analysis Acute Physiology and Chronic Health Evaluation (APACHE) II score (P = 0.02), time on NIV before intubation (P = 0.001) and baseline PaCO2 levels (P = 0.01) were strongly associated with mortality.Conclusion:Noninvasive ventilation failure and mortality rates were significantly higher when used outside level I recommendations. APACHE II score, baseline PaCO2 and duration on NIV prior to intubation were predictors of increased mortality.