Ventilation In COPD Patients Research Articles

Cluster Analysis of Home Mechanical Ventilation in COPD Patients: A Picture of the Real World and Its Impact on Mortality

BackgroundTreatment of chronic hypercapnic failure in COPD patients with home noninvasive ventilation (HNIV) remains unclear. AimTo create a curated cohort of all COPD patients on HNIV in Catalonia, perform a cluster analysis, and evaluate mortality evolution. Study design and methodsThis study was a multicenter, observational study including all COPD patients on HNIV on 1st January of 2018. Patients were selected through the Catalan Health Service, and administrative and clinical data were obtained in the previous four years. Principal component analysis of mixed data and hierarchical clustering were performed to identify clusters of patients. Mortality was evaluated from 1 January 2018 until 31 December 2020. ResultsA total of 247 patients were enrolled. They were mostly male (78.1%), with a median (SD) age of 70.4 (9.4) years old. In 60%, 55% and 29% of patients, obesity, sleep apnea and heart failure coexisted, respectively. Cluster analysis identified four well-differentiated groups labeled for their clinical characteristics: (1) obese smokers, (2) very severe COPD, (3) sleep apnea and (4) older comorbid males. Patients belonging to Clusters (2) and (4) had a worse prognosis than patients in Clusters (1) and (3). InterpretationA high heterogeneity in the prescription of HNIV was demonstrated. Cluster analysis identifies four different groups, of which only one had COPD as the main cause of ventilation, while the other three clusters showed a predominance of other comorbidities. This leads to different survival outcomes, including an overlapping phenotype of obesity-related disease and sleep apnea with better survival.

METABOLIC ALKALOSIS DRIVING RESPIRATORY FAILURE IN POST ACUTECOVID-19 SYNDROME

TOPIC: Pulmonary Physiology TYPE: Medical Student/Resident Case Reports INTRODUCTION: Survival of the acute phase of COVID-19 infection can leave patients with multiple long-term sequelae described as Post-acute covid-19 syndrome (PACS). We present a case of a patient with PACS manifested as pulmonary fibrosis, carbon dioxide retention and difficulty weaning from BIPAP that experienced dramatic improvement following treatment with Acetazolamide. CASE PRESENTATION: 66-year-old female presented for 7 days of worsening cough and shortness of breath. She was found to be hypoxic on presentation with COVID-19 test resulting positive and was admitted. Her hospital course was complicated by rapid increase in oxygen requirements with the initiation of BIPAP on hospital day 19. At this time, arterial blood gas (ABG) revealed mixed respiratory acidosis and metabolic alkalosis with pH 7.41, CO2 77 and HCO3 of 43. She was continued on BIPAP for several days before being weaned to high flow nasal cannula. On hospital day 44 she was noted to be increasingly lethargic. ABG obtained at this time showed pH of 7.3, CO2 >110 and HCO3 of 68. She was placed back on BIPAP and serial ABGs were monitored. At about 12 hours after the initiation of BIPAP, she developed a post-hypercapnic alkalosis with ABG demonstrating pH 7.46, CO2 90 and HCO3 50. At this time, BIPAP was stopped and Acetazolamide was administered at 500mg IV daily for 2 days.The patient experienced significant improvement in her mental status and work of breathing. She was weaned to nasal cannula. An ABG obtained the day following the second acetazolamide dose showed improvement in both metabolic alkalosis and respiratory acidosis with pH 7.42, CO2 62 and HCO3 34. DISCUSSION: The role of correcting metabolic alkalosis in hypercapnic respiratory failure has been described over the years. Trials conducted have utilized the carbonic anhydrase inhibitor Acetazolamide to promote renal bicarbonate excretion with goal statistical endpoints of early liberation from mechanical ventilation, reduced hospital stay or mortality but have generally failed to demonstrate statistically significant benefit.In the DIABOLO trial, mechanically ventilated COPD patients with metabolic alkalosis were assigned to either Acetazolamide infusion or placebo. The study concluded without statistically significant benefit in the primary outcome (duration of mechanical ventilation) or important secondary outcomes such as ICU mortality or ICU length of stay. However, the average serum bicarbonate level was only 27 between the two groups. This leads to the question if acetazolamide may have benefits in specific patients with a more severe alkalosis in the right clinical context as shown in this case study. CONCLUSIONS: Alkalosis may surpass compensation and perpetuate hypercapnic respiratory failure. This may be especially common ARDS patients managed with a fluid restricted approach. Administration of acetazolamide may benefit appropriately selected patients. REFERENCE #1: Nalbandian A, Sehgal K, Gupta A, et al. Post-acute COVID-19 syndrome. Nat Med. Published online March 22, 2021. doi:10.1038/s41591-021-01283-z REFERENCE #2: Faisy C, Meziani F, Planquette B, et al. Effect of Acetazolamide vs Placebo on Duration of Invasive Mechanical Ventilation Among Patients With Chronic Obstructive Pulmonary Disease: A Randomized Clinical Trial. JAMA. 2016;315(5):480-488. doi:10.1001/jama.2016.0019 REFERENCE #3: Adamson R, Swenson ER. Acetazolamide Use in Severe Chronic Obstructive Pulmonary Disease. Pros and Cons. Ann Am Thorac Soc. 2017;14(7):1086-1093. doi:10.1513/AnnalsATS.201701-016FR DISCLOSURES: No relevant relationships by Jackson Heilbronn, source=Web Response no disclosure on file for Christina Kwon;No relevant relationships by Michael Ulrich, source=Web Response

The NIVO score: can it help to improve noninvasive ventilation in daily clinical practice?

<b>The study of Hartley designed an easy-to-use score to predict mortality in noninvasively ventilated COPD patients. More information about NIV is gained, but the exact measures on how to improve NIV in clinical practice remains uncertain.</b>https://bit.ly/3tFfg8F

Is COPD associated with increased risk for microaspiration in intubated critically ill patients?

BackgroundAlthough COPD patients are at higher risk for aspiration when breathing spontaneously, no information is available on the risk for microaspiration in invasively ventilated COPD patients. The aim of our study was to determine the relationship between COPD and abundant microaspiration in intubated critically ill patients.MethodsThis was a retrospective analysis of prospectively collected data, provided by 3 randomized controlled trials on microaspiration in critically ill patients receiving invasive mechanical ventilation for more than 48 h. Abundant microaspiration was defined as the presence of pepsin and or alpha-amylase at significant levels in tracheal aspirates. In all study patients, pepsin and alpha-amylase were quantitatively measured in all tracheal aspirates collected during a 48-h period. COPD was defined using spirometry criteria.ResultsAmong the 515 included patients, 70 (14%) had proven COPD. Pepsin and alpha-amylase were quantitatively measured in 3873 and 3764 tracheal aspirates, respectively. No significant difference was found in abundant microaspiration rate between COPD and non-COPD patients (62 of 70 patients (89%) vs 366 of 445 (82%) patients, p = 0.25). Similarly, no significant difference was found in abundant microaspiration of gastric contents (53% vs 45%, p = 0.28), oropharyngeal secretions (71% vs 71%, p = 0.99), or VAP (19% vs 22%, p = 0.65) rates between the two groups. No significant difference was found between COPD and non-COPD patients in duration of mechanical ventilation, ICU length of stay, or ICU mortality.ConclusionsOur results suggest that COPD is not associated with increased risk for abundant microaspiration in intubated critically ill patients.

Use of Continuous Sedation Protocol Versus Interrupted Sedation Protocol in COPD Patients Mechanically Ventilated with Acute Respiratory Failure

Critically ill patients who require mechanical ventilation are often given contiouous intravenous infusions of sedative drugs to treat anxiety. Tranquilizers are mixed ceaselessly as contrasted and discontinuous bolus imbuement, this methodology gives a more steady degree of sedation and may increment patients'comfort, yet it expanded sedation may restrict clinicians capacity to decipher physical assessments. Be that as it may, every day interference of narcotic implantations to permit patients to wake up may improve the circumstance by permitting clinicians to smooth out the organization of tranquilizers while guaranteeing ideal solace for patients. To think about between consistent sedation convention versus intruded on sedation convention in COPD precisely ventilated patients as for span of mechanical ventilation, the time required for patients to stir, and the recurrence of unfriendly occasions. This examination was completed on 45 subjects with signs and manifestations of COPD and demonstrated radiologically; classified into three gatherings; 15 precisely ventilated COPD patients got persistent sedation convention [group 1], 15 precisely ventilated COPD patients with day by day interference sedation convention [group 2] and 15 precisely ventilated COPD patients without convention of sedation [group 3]. Term of mechanical ventilation was altogether shorter in intruded on sedation gathering and gathering without convention of sedation. Likewise, the ideal opportunity for patients to stir was essentially shorter in intruded on sedation gathering and gathering without convention of sedation. Every day interference sedation convention limits the confusions from total sedation, without an expansion in unfavorable occasions or different inconveniences.

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.

The Predictive Value of the Integrated Weaning Indices in Mechanically Ventilated COPD Patients

The Predictive Value of the Integrated Weaning Indices in Mechanically Ventilated COPD Patients

The Predictive Value of the Integrated Weaning Indices in Mechanically Ventilated COPD Patients

Background: COPD exacerbations necessitating mechanical ventilation representing important aspect of disease management. Attempts to search for better weaning index is a continuous process. Aim of the work: was to study the accuracy of the integrated weaning indices including, CROP index and CORE index as predictors of weaning success in COPD exacerbation under mechanical ventilation. Patients and Methods: 102 COPD patients necessitating mechanical ventilation >24 h underwent daily screen of subjective and objective indices for weaning readiness, and patients were classified according to weaning outcome into successful group (Group S) (60 patients) and failure group (Group F) (42 patients). Results: There were no significant observed difference regarding the demographic data between the successful and the failure groups. There was highly significant difference between both weaning groups regarding dynamic compliance, NIF, P0.1, CROP index and CORE index (P value < 0.05). AUC of CROP index (0.80) was moderately precise compared with that of CORE index (0.63). Conclusion: CROP index is superior to CORE index as a predictor of weaning success in mechanically ventilated COPD patients

Daily use of extracorporeal CO2 removal in a critical care unit: indications and results

BackgroundWhile outcome improvement with extracorporeal CO2 removal (ECCO2R) is not demonstrated, a strong pathophysiological rational supports its use in the setting of acute respiratory distress syndrome (ARDS) and COPD exacerbation. We aimed to describe our single-center experience of ECCO2R indications and outcome.MethodsPatients treated with ECCO2R in our medial ICU, from March 2014 to November 2017, were retrospectively enrolled. Primary end point was evolution of ventilator settings during the two first days following ECCO2R start.ResultsThirty-three patients received ECCO2R. Seventeen were managed with Hemolung®, 10 with Prismalung®, 4 with ILA®, and 2 with Cardiohelp®. Indications for ECCO2R were mild or moderate ARDS (n = 16), COPD exacerbation (n = 11), or uncontrolled hypercapnia due to other causes (n = 6). Four patients were not intubated at the time of ECCO2R start. Median duration of ECCO2R treatment was 7 days [5–10]. In ARDS patients, between baseline and day 2, median tidal volume and driving pressure decreased from 5.3 [4.4–5.9] mL/kg and 10 [8–15] to 3.8 [3.3–4.1] mL/kg and 9 [8–11], respectively. Prone positioning was performed in 10 of the 16 patients, without serious adverse event. In COPD patients, between baseline and day 2, median ventilation minute and PaCO2 decreased significantly from respectively 7.6 [6.6–8.7] L/min and 9.4 [8.4–10.1] kPa to 5.8 [4.9–6.2] L/min and 6 [5.3–6.8] kPa. Four out of 11 COPD patients were extubated while on ECCO2R. Device thrombosis occurred in 5 patients (15%). Hemolysis was documented in 16 patients (48%). One patient died of intracranial hemorrhage, while on ECCO2R. Twenty-four patients were discharged from ICU alive. Twenty-eight day mortality was 31% in ARDS, 9% in COPD patients, and 50% in other causes of refractory hypercapnic respiratory failure.ConclusionECCO2R was useful to apply ultra-protective ventilation among ARDS patients and improved PaCO2, pH, and minute ventilation in COPD patients.

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.

Ambulatory care of non-invasive mechanical ventilation in COPD patients with global decompensated respiratory acidosis

Ambulatory care of non-invasive mechanical ventilation in COPD patients with global decompensated respiratory acidosis

Effect of salmeterol/fluticasone combination on the dynamic changes of lung mechanics in mechanically ventilated COPD patients: a prospective pilot study.

BackgroundThe combined therapy of inhaled corticosteroids and long-acting beta-2 agonists for mechanically ventilated patients with COPD has never been explored. Therefore, the aim of this study was to investigate their dynamic effects on lung mechanics and gas exchange.Materials and methodsTen mechanically ventilated patients with resolution of the causes of acute exacerbations of COPD were included. Four puffs of salmeterol 25 μg/fluticasone 125 μg combination therapy were administered. Lung mechanics, including maximum resistance of the respiratory system (Rrs), end-inspiratory static compliance, peak inspiratory pressure (PIP), plateau pressure, and mean airway pressure along with gas exchange function were measured and analyzed.ResultsSalmeterol/fluticasone produced a significant improvement in Rrs and PIP after 30 minutes. With regard to changes in baseline values, salmeterol/fluticasone inhalation had a greater effect on PIP than Rrs. However, the therapeutic effects seemed to lose significance after 3 hours of inhaled corticosteroid/long-acting beta-2 agonist administration.ConclusionThe combination of salmeterol/fluticasone-inhaled therapy in mechanically ventilated patients with COPD had a significant benefit in reducing Rrs and PIP.

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.

Diaphragm Ultrasound as a Novel Guide of Weaning From Invasive Ventilation

Background: Predictive guides of weaning from invasive ventilation are often erroneous. Among the numerous parameters used in practice, the rapid shallow breathing index is one of the most accurate. Aim: The diaphragm thickening (DT) measured by ultrasound was evaluated as a weaning predictor compared with the rapid shallow breathing index(RSBI). Patient and Methods: A prospective study included 78 patients with COPD exacerbations. All patients were ventilated in pressure support through endotracheal tube. During spontaneous breathing trial (SBT), the right diaphragm was visualized in the zone of apposition using a 7.5 MHz linear ultrasound probe. DT was calculated as percentage from the following formula: Thickness at end inspiration − Thickness at end expiration / Thickness at end expiration. It was recorded at total lung capacity (TLC) and residual volume (RV). The RSBI was calculated. Weaning failure was defined as the inability to maintain spontaneous breathing for at least 48 hours, without any form of ventilatory support. Results: A significant difference between DT at TLC and RV was observed both in patients who succeeded SBT and patients who failed. DT was significantly different between patients who failed and patients who succeeded SBT. A cutoff value of a DT >40% was associated with a successful SBT with a sensitivity of 88%, a specificity of 92%, a positive predictive value (PPV) of 95%, and a negative predictive value (NPV) of 82%. On the other hand , RSBI Conclusions: DT assessed by ultrasound is an excellent predictor of weaning outcome in mechanically ventilated COPD patients.

Tei Index versus Pro BNP as Predictors of Weaning Failure in Mechanically Ventilated Chronic Obstructive Pulmonary Disease Patients

Objective: This prospective cohort study was designed to assess the rule of myocardial performance (Tei) index and NT-Pro BNP serum levels in prediction of weaning failure in mechanically ventilated COPD patients. Methods: Forty patients with respiratory failure due to acute exacerbation of COPD were enrolled to this study. All patients underwent a comprehensive echocardiographic examination including tissue doppler imaging within first 12 hours of admission. NT-pro BNP serum levels were measured on admission. Patients were followed up for outcome of weaning failure. Results: Right ventricular Tei index was higher in patients with failed weaning in comparison to successfully weaned patients (mean 0.66 versus 0.36, P < 0.001), also left ventricular Tei index was higher in patients who failed to be weaned (mean 0.45 versus 0.36, P = 0.007). There was no difference in serum NT-Pro BNP between successfully weaned patients and patients with weaning failure. Right ventricular Tei index showed higher accuracy in predicting weaning failure than the left ventricular Tei index (AUC 0.932 versus 0.754), while serum NT-Pro BNP showed no discrimination in predicting weaning failure (AUC 0.556). Conclusion: Tei index was superior to NT-ProBNP in prediction of weaning failure in COPD patients.

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...

Effect of respiratory muscles training in weaning of mechanically ventilated COPD patients

BackgroundInspiratory muscle weakness is common in patients receiving mechanical ventilation, especially COPD patients with prolonged duration of mechanical ventilation. Inspiratory muscle training could limit or reverse these unhelpful sequelae and facilitate more rapid and successful weaning. ObjectiveAssessment of the effect of respiratory muscle training in weaning of mechanically ventilated COPD patients admitted in respiratory ICU in the Abbassia chest hospital. Patients and methodsThe study was conducted on 40 COPD patients admitted to the respiratory intensive care unit in the Abbassia chest hospital in the period between October-2011 and March-2013. All patients were diagnosed as having acute exacerbation of COPD with acute respiratory failure necessitating mechanical ventilatory support and difficult weaning; patients were subdivided into 2 groups: GROUP (A): (20 patients) include patients who received respiratory muscle training and GROUP (B): (20 patients) include patients who did not receive inspiratory muscle training. ResultsThere was a significant difference between the 2 groups as regards the primary outcomes including weaning success rate, duration of mechanical ventilation, length of stay in ICU, length of stay in hospital. Also there was a significant improvement of secondary outcomes in group (A) including PO2, O2 saturation, TV, RR, MIP over the 5days of IMT; while there was a significant difference between the 2 groups regarding the above secondary outcomes in favor to group (A). ConclusionInspiratory muscle training increases muscle strength and endurance as well as it assists in weaning from mechanical ventilation in COPD patients with difficult weaning.

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.