Noninvasive Ventilation In COPD Patients Research Articles

Home initiation of chronic non-invasive ventilation in COPD patients with chronic hypercapnic respiratory failure: a randomised controlled trial

IntroductionChronic non-invasive ventilation (NIV) has become evidence-based care for stable hypercapnic COPD patients. While the number of patients increases, home initiation of NIV would greatly alleviate the healthcare burden. We...

Nasal high-flow therapy compared with non-invasive ventilation in COPD patients with chronic respiratory failure: A randomized controlled cross-over trial.

Non-invasive ventilation (NIV) is part of the standard of care for hypercapnic respiratory failure secondary to COPD, but may be poorly tolerated. Preliminary evidence suggests nasal high-flow (NHF) therapy may improve hypercapnia in COPD and be well tolerated. We compared NHF and NIV in people with COPD and chronic hypercapnic respiratory failure. Single-blind randomized controlled two-way cross-over single-centre trial was conducted in New Zealand. Twenty-four participants with stable hypercapnic COPD received: NHF at 45 L/min and NIV at 15/4 cm H2 O, each for 60 min with a 15-min washout in between. The primary outcome was transcutaneous partial pressure of carbon dioxide (PtCO2 ) at 60 min, adjusted for baseline. NIV reduced the PtCO2 more than NHF (mean (SD) at 60 min by -5.3 (5.0) vs -2.5 (3.5) mm Hg; difference: -2.8 (-5.0 to -0.5) P = 0.021). Difference across all time points was -2.5 mm Hg (95% CI -4.5 to -0.5, P = 0.016). There was no significant difference in the proportion of participants with a reduction of PtCO2 ≥ 4 or ≥ 8 mm Hg. Participants rated NHF significantly better for ease of application, comfort and fit. In stable COPD patients with chronic hypercapnia, NIV resulted in a greater reduction in PtCO2 compared with NHF, which was of uncertain clinical significance. NHF was better tolerated than NIV and may be a therapeutic option for some people with hypercapnic respiratory failure. ACTRN12616001701415 at www.anzctr.org.au.

Interfaces and ventilator settings for long-term noninvasive ventilation in COPD patients.

IntroductionThe establishment of high-intensity (HI) noninvasive ventilation (NIV) that targets elevated PaCO2 has led to an increase in the use of long-term NIV to treat patients with chronic hypercapnic COPD. However, the role of the ventilation interface, especially in more aggressive ventilation strategies, has not been systematically assessed.MethodsVentilator settings and NIV compliance were assessed in this prospective cross-sectional monocentric cohort study of COPD patients with pre-existing NIV. Daytime arterialized blood gas analyses and lung function testing were also performed. The primary end point was the distribution among study patients of interfaces (full-face masks [FFMs] vs nasal masks [NMs]) in a real-life setting.ResultsThe majority of the 123 patients studied used an FFM (77%), while 23% used an NM. Ventilation settings were as follows: mean ± standard deviation (SD) inspiratory positive airway pressure (IPAP) was 23.2±4.6 mbar and mean ± SD breathing rate was 16.7±2.4/minute. Pressure support ventilation (PSV) mode was used in 52.8% of patients, while assisted pressure-controlled ventilation (aPCV) was used in 47.2% of patients. Higher IPAP levels were associated with an increased use of FFMs (IPAP <21 mbar: 73% vs IPAP >25 mbar: 84%). Mean compliance was 6.5 hours/day, with no differences between FFM (6.4 hours/day) and NM (6.7 hours/day) users. PaCO2 assessment of ventilation quality revealed comparable results among patients with FFMs or NMs.ConclusionThis real-life trial identified the FFM as the predominantly used interface in COPD patients undergoing long-term NIV. The increased application of FFMs is, therefore, likely to be influenced by higher IPAP levels, which form part of the basis for successful application of HI-NIV in clinical practice.

Delayed but successful response to noninvasive ventilation in COPD patients with acute hypercapnic respiratory failure.

BackgroundWe evaluated a new noninvasive ventilation (NIV) protocol that allows the pursuit of NIV in the case of persistent severe respiratory acidosis despite a first NIV challenge in COPD patients with acute hypercapnic respiratory failure (AHRF).Patients and methodsA prospective observational multicentric pilot study was conducted in three tertiary hospitals over a 12-month study period. A total of 155 consecutive COPD patients who were admitted for AHRF and treated by NIV were enrolled. Delayed response to NIV was defined as a significant clinical improvement in the first 48 h following NIV initiation despite a persistent severe respiratory acidosis (pH <7.30) after the first 2 h of NIV trial.ResultsNIV failed in only 10 patients (6.5%). Delayed responders to NIV (n=83, 53%) exhibited similar nutritional status, comorbidities, functional status, frailty score, dyspnea score, and severity score at admission, compared with early responders (n=62, 40%). Only age (66 vs 70 years in early responders; P=0.03) and encephalopathy score (3 [2–4] vs 3 [2–4] in early responders; P=0.015) were different among the responders. Inhospital mortality did not differ between responders to NIV (n=10, 12% for delayed responders vs n=10, 16% for early responders, P=0.49). A second episode of AHRF occurred in 20 responders (14%), equally distributed among early and delayed responders to NIV (n=9, 14.5% in early responders vs n=11, 13% in delayed responders; P=0.83), with a poor survival rate (n=1, 5%).ConclusionMost of the COPD patients with AHRF have a successful outcome when NIV is pursued despite a persistent severe respiratory acidosis after the first NIV trial. The outcome of delayed responders is similar to the one of the early responders. On the contrary, the second episode of AHRF during the hospital stay carries a poor prognosis.

Trends in use and impact on outcome of empiric antibiotic therapy and non-invasive ventilation in COPD patients with acute exacerbation.

BackgroundEmpiric antibiotic therapy is routinely prescribed in patients with acute COPD exacerbations (AECOPD) requiring ventilatory support on the basis of studies including patients conventionally ventilated. Whether this practice remains valid to current management with first-line non-invasive ventilation (NIV) is unclear.MethodsIn a cohort of ICU patients admitted between 2000 and 2012 for AECOPD, we analyzed the trends in empiric antibiotic therapy and in primary ventilatory support strategy, and their respective impact on patients’ outcome.Results440 patients admitted for 552 episodes were included; primary NIV use increased from 29 to 96.7 % (p < 0.001), whereas NIV failure rate decreased significantly (p = 0.004). In parallel, ventilator-associated pneumonia (VAP) rate, VAP density and empiric antibiotic therapy use decreased (p = 0.037, p = 0.002, and p < 0.001, respectively). These figures were associated with a trend toward lower ICU mortality rate (p = 0.058). Logistic regression showed that primary NIV use per se was protective against fatal outcome [odds ratios (OR) = 0.08, 95 %CI 0.03–0.22; p < 0.001], whereas NIV failure, VAP occurrence, and cardiovascular comorbidities were associated with increased ICU mortality [OR = 17.6 (95 %CI 5.29–58.93), 11.5 (95 %CI 5.17–25.45), and 3 (95 %CI 1.37–6.63), respectively]. Empiric antibiotic therapy was associated with decreased VAP rate (log rank; p < 0.001), but had no effect on mortality (log rank; p = 0.793).ConclusionsThe sustained increase in NIV use allowed a decrease in empiric antibiotic prescriptions in AECOPD requiring ventilatory support. Primary NIV use and its success, but not empiric antibiotic therapy, were associated with a favorable impact on patients’ outcome.

Nocturnal non-invasive ventilation in COPD patients with prolonged hypercapnia after ventilatory support for acute respiratory failure: a randomised, controlled, parallel-group study

IntroductionThe effectiveness of non-invasive positive pressure ventilation (NIV) in COPD patients with prolonged hypercapnia after ventilatory support for acute respiratory failure (ARF) remains unclear. We investigated if nocturnal NIV in...

Physical Training and Noninvasive Ventilation in COPD Patients: A Meta-Analysis

Exercise training improves both exercise tolerance and quality of life in patients with COPD. The intensity of exercise training is crucial to achieve a true physiologic effect. However, in COPD patients, exertional dyspnea and leg fatigue mean that the patient cannot maintain intensity of training for enough time to yield a physiologic training effect. The use of noninvasive ventilation (NIV) support has been proposed as an alternative strategy to improve exercise tolerance and respiratory and cardiovascular performances. The first aim of our meta-analysis was to evaluate exercise training with NIV in terms of physiologic effects after the completion of a pulmonary rehabilitation program. The second aim was to investigate the dose-response relationship between physical improvement and training intensity. Literature research was performed using MEDLINE, Embase, and CINAHL. Meta-analysis and meta-regressions were performed using random effects models. Eight studies provided a proper description of a training schedule in stable COPD patients. A similar effect between NIV and placebo was observed for the outcomes considered despite differences between studies. However, subjects experienced a relevant and statistically significant improvement after rehabilitation for almost all of the outcomes considered. Heart rate (6 beats/min [95% CI 0.94-11.01], P = .02), work load (9.73 W [95% CI 3.78-15.67], P < .001), and oxygen consumption (242.11 mL/min [95% CI 154.93-329.9], P < .001) significantly improved after training. Improvements in heart rate and work load were significantly correlated to training intensity. Given the small number of available studies, the small sample sizes, and the complete absence of power calculation, we think that this topic deserves a more in-depth investigation. Randomized clinical trials with larger sample sizes based on statistical power calculations and designed to investigate the effect of training duration and intensity on rehabilitation are needed to confirm results in this important field.

Does inspiratory behaviour affect the efficiency of non-invasive ventilation in COPD patients?

Non-invasive ventilation (NIV) is more and more used. Some failures of the technique have been reported, and efforts are needed to understand them. Collaboration (inspiratory behaviour) of the patient during NIV could play a role in the success of this technique. We have studied the influence of this one on the efficiency of NIV. While ventilating 10 stable chronic obstructive pulmonary disease patients with a nasal pressure support ventilation (PSV), we measured their flow and volume with a pneumotachograph and oesophageal and gastric pressures during three different respiratory voluntary behaviours: relaxed inspiration, active inspiratory effort and resisted inspiration. We showed that when compared with the relaxed inspiration: (a) Active inspiratory effort increases slightly minute ventilation from 14.8±4.7 to 15.41±4.19 during PSV 10/0 without change of breathing frequency but with an important increase of inspiratory work (W OB) from 14.47± 9.43 to 28.55±25.35 J/min ( P=0.008). PEEP i increases with active behaviour during PSV but not during BiPAP. (b) A′ resisted inspiration decreases inspiratory work (to 7.53±8.6 J/min) at the price of a decrease of the minute ventilation to 11.47±4.20 l/min( P=0.06). Results of ventilation, PEEP i and work parameters were identical during the bilevel pressure support (15/5 cm H 2O). The aims of NIV being to increase ventilation and unload the inspiratory muscles, our results suggest that during NIV, a relaxed spontaneous breathing is preferable. These differences between the inspiratory behaviours could affect the expected benefits of PSV in acutely ill patients.

Predicting the Result of Noninvasive Ventilation in Severe Acute Exacerbations of Patients With Chronic Airflow Limitation

To analyze prospectively the factors related to the success of noninvasive ventilation (NIV) in the treatment of acute exacerbations of chronic airflow limitation (CAFL) and to generate a multiple regression model in order to detect which patients can be successfully treated by this method. A respiratory medicine ward of a referral hospital. Initially, we examined 44 episodes of acute respiratory failure in 36 patients with CAFL in whom mechanical ventilation was advisable. In 34 of 44 episodes (77%), NIV was used successfully. Patients in whom NIV succeeded had a lower FEV(1) prior to admission, a higher level of consciousness (LC), and significant improvements in PaCO(2), pH, and LC after 1 h of NIV. A logistic regression model consisting of baseline FEV(1) and PaCO(2) values, initial PaCO(2), pH, and LC values on admission, and PaCO(2) values after 1 h of NIV allowed us to correctly classify > 95% of the 44 episodes in which the outcome was successful. In the second part of the study, we prospectively validated the equation in another 15 consecutive CAFL patients with acute hypercapnic respiratory failure. NIV successfully treated 12 patients (80%), and the model correctly classified 14 patients (93%). Good LC at the beginning of NIV and improvements in pH, PaCO(2), and LC values after 1 h of NIV are associated with successful responses to NIV in COPD patients with acute hypercapnic respiratory failure. Our validated multiple regression model confirms that these variables predict the result of NIV in acute hypercapnic failure in CAFL patients.