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Stair climbing is associated with dynamic pulmonary hyperinflation and the development of severe dyspnea in patients with chronic obstructive pulmonary disease (COPD). This study aimed to assess whether (i) continuous positive airway pressure (CPAP) applied during stair climbing prevents dynamic hyperinflation and thereby reduces exercise-induced dyspnea in oxygen-dependent COPD-patients, and (ii) the CPAP-device and oxygen tank can be carried in a hip belt. In a randomised cross-over design, oxygen-dependent COPD patients performed two stair-climbing tests (44 steps): with supplemental oxygen only, then with the addition of CPAP (7 mbar). The oxygen tank and CPAP-device were carried in a hip belt during both trials. Eighteen COPD patients were included in the study. Although all patients could tolerate stair climbing with oxygen alone, 4 patients were unable to perform stair climbing while using CPAP. Fourteen COPD patients (mean FEV1 36 ± 14% pred.) completed the trial and were analyzed. The mean flow rate of supplemental oxygen was 3 ± 2 l/min during stair climbing. Lung hyperinflation, deoxygenation, hypoventilation, blood lactate production, dyspnea and the time needed to manage stair climbing were not improved by the application of CPAP (all p > 0.05). However, in comparison to climbing with oxygen alone, limb discomfort was reduced when oxygen was supplemented with CPAP (p = 0.008). In conclusion, very severe COPD patients are able to carry supporting devices such as oxygen tanks or CPAP-devices in a hip belt during stair climbing. However, the application of CPAP in addition to supplemental oxygen during stair climbing prevents neither exercise-induced dynamic hyperinflation, nor dyspnea.

Continuous partial pressure of carbon dioxide (PCOThe present study therefore performed methodological comparisons of PaCOA total of 60 patients (COPD (n = 30) and non-COPD (n = 30)) completed the protocol. Mean PCOOur data therefore support PtcCO

Background. Two disease-specific questionnaires have been developed to assess health-related quality of life (HRQL) in patients with chronic respiratory failure: the Severe Respiratory Insufficiency (SRI) Questionnaire and the Maugeri Respiratory Failure (MRF) Questionnaire. We aimed to compare the characteristics of the SRI, MRF-26, and St. George’s Respiratory Questionnaire (SGRQ) for use in patients with home noninvasive ventilation (NIV). Methods. Fifty-six outpatients receiving long-term NIV were recruited and underwent assessments of pulmonary function, arterial blood gas, HRQL, dyspnea, and psychological status. Results. Correlations of the SRI and MRF-26 with the SGRQ were modest. While pulmonary function was weakly related to only some domains of the SRI and MRF-26, the modified Medical Research Council (mMRC) dyspnea scale and Hospital Anxiety and Depression Scale (HADS) were significantly related to all domains of the SRI and MRF-26. Multiple regression analyses showed that HADS depression and mMRC accounted for 34% and 27% of the variance in the SRI, 24% and 37% in the MRF-26, and 17% and 46% in the SGRQ, respectively. Conclusions. The SRI and MRF-26 were reliable questionnaires for patients receiving long-term NIV. Dyspnea and psychological status were their main common determinants. The SRI covers more psychological health impairments than the MRF. This trial is registered with ClinicalTrials.gov Identifier: NCT00905476.

Evidence is weak for the ability of long-term non-invasive positive pressure ventilation (NPPV) to improve survival in patients with stable hypercapnic chronic obstructive pulmonary disease (COPD). Previous prospective studies did not target a reduction in hypercapnia when adjusting ventilator settings. This study investigated the effect of long-term NPPV, targeted to markedly reduce hypercapnia, on survival in patients with advanced, stable hypercapnic COPD.This investigator-initiated, prospective, multicentre, randomised, controlled clinical trial enrolled patients with stable GOLD stage IV COPD and a partial carbon dioxide pressure (PaCO2) of 7 kPa (51.9 mm Hg) or higher and pH higher than 7.35. NPPV was targeted to reduce baseline PaCO2 by at least 20% or to achieve PaCO2 values lower than 6.5 kPa (48.1 mm Hg). Patients were randomly assigned (in a 1:1 ratio) via a computer-generated randomisation sequence with a block size of four, to continue optimised standard treatment (control group) or to receive additional NPPV for at least 12 months (intervention group). The primary outcome was 1-year all-cause mortality. Analysis was by intention to treat. The intervention was unblinded, but outcome assessment was blinded to treatment assignment. This study is registered with ClinicalTrials.gov, number NCT00710541.Patients were recruited from 36 respiratory units in Germany and Austria, starting on Oct 29, 2004, and terminated with a record of the vital status on July 31, 2011. 195 patients were randomly assigned to the NPPV group (n=102) or to the control group (n=93). All patients from the control group and the NPPV group were included in the primary analysis. 1-year mortality was 12% (12 of 102 patients) in the intervention group and 33% (31 of 93 patients) in the control group; hazard ratio 0.24 (95% CI 0.11-0.49; p=0.0004). 14 (14%) patients reported facial skin rash, which could be managed by changing the type of the mask. No other intervention-related adverse events were reported.The addition of long-term NPPV to standard treatment improves survival of patients with hypercapnic, stable COPD when NPPV is targeted to greatly reduce hypercapnia.German Lung Foundation; ResMed, Germany; Tyco Healthcare, Germany; and Weinmann, Germany.

Background: The German guideline on long-term oxygen therapy (LTOT) was published in 2008 by the German Respiratory Society (DGP), while the British Thoracic Society (BTS) published their most recent guideline in 2015. Objectives: The aim of the present article was to highlight the major areas of consensus and disagreement in the recently published BTS and DGP guidelines on LTOT. Methods: The BTS and DGP guidelines were directly compared in terms of congruencies and differences. A critical appraisal was then performed and authors' suggestions were provided. Results: The 2 guidelines are almost congruent in 2 major areas, namely, (1) the indication criteria for LTOT in chronic obstructive pulmonary disease (COPD) patients at rest and (2) the recommended duration of LTOT over a 24-h period. However, 8 major areas in which the guidelines differ considerably were identified: (1) techniques for blood gas analysis; (2) timing of LTOT in stable patients; (3) LTOT in post-exacerbation COPD patients; (4) ambulatory oxygen therapy; (5) nocturnal oxygen therapy; (6) titration of oxygen flow rates; (7) follow-up visits; and (8) LTOT for patients who still smoke. Furthermore, the BTS guideline is much more detailed, includes more references (161 vs. 71) and is more up to date than the DGP guideline. Conclusion: There are major differences between the 2 guidelines. Many of the aspects raised by the BTS guideline appear to be reasonable with regard to the current literature, clinical experience and prescription practices. However, an international consensus on LTOT is lacking.

The aim of this study was to develop and validate the professional translation and cultural adaptation of the Portuguese Severe Respiratory Insufficiency (SRI) Questionnaire.The sample was composed of 93 patients (50 male patients, 53.8%) with a mean age of 66.3 years. The most frequent diagnostic groups were chronic obstructive pulmonary disease, obesity hypoventilation syndrome and restrictive chest wall disorders.The patients were asked to fill in both the SRI and SF-36 questionnaires. Factor analysis of the SRI questionnaire was performed leading to an explained variance of 73%, and resulted in 13 components. When analyzing the reliability, we obtained values for Cronbach's alpha above 0.70 for most subscales with the reliability of the summary scale being even higher (0.84).This professional translation and cultural adaptation of the Portuguese SRI Questionnaire has good psychometric properties which are similar, not only to the original, but also to other translations. These characteristics make this questionnaire applicable to the Portuguese population receiving home mechanical ventilation for severe respiratory insufficiency. Keywords: Questionnaire, Portuguese, Home mechanical ventilation, Quality of life

A restful sleep is essential for regenerative processes and remains crucial for patients recovering from stressful periods in the intensive care unit. The current study aimed to assess sleep quality in critically ill patients receiving invasive mechanical ventilation within a specialized weaning unit in hospital. Tracheotomized subjects undergoing prolonged weaning from mechanical ventilation were included in the study. Polysomnography and gas exchange monitoring was performed during nocturnal ventilation. Subjective evaluation of sleep quality and health-related quality of life were also assessed. Nineteen subjects completed the study protocol. Sleep architecture was highly heterogeneous across individual subjects. Mean total sleep time (TST) was 273 ± 114 min, sleep efficacy 70 ± 23%, slow-wave sleep 25.7 ± 18.4%/TST, rapid eye movement sleep 9.6 ± 7.5%/TST, and arousal index 18.7 ± 12.4/h. No significant difference in sleep quality was found between subjects with successful (N = 7) or unsuccessful (N = 12) weaning. Bicarbonate levels were negatively correlated both with sleep efficacy and sleep quality, that latter of which was subjectively assessed by the subjects using a visual analogue scale. Subjects who were undergoing prolonged weaning from mechanical ventilation and admitted to a specialized weaning unit, showed reduced sleep quality with preservation of high amounts of slow-wave sleep.

The technology underlying the development of novel ventilatory modes for long-term noninvasive ventilation of patients with chronic hypercapnia is continuously evolving. Volume-targeted pressure-controlled ventilation is a hybrid ventilation mode designed to combine the advantages of conventional ventilation modes, while avoiding their drawbacks. However, manufacturers have created different names and have patented algorithms and set-up variables, which can result in confusion for physicians and respiratory therapists. In addition, clear evidence for the superiority of this novel mode has not yet been established. These factors have most likely hindered more widespread use of this mode in clinical practice. The current review presents the rationale, working principles, characteristics and set-up recommendations associated with volume-targeted modes. In addition, it summarises the clinical and laboratory studies that have challenged this mode.

Background: Thoracotomy leads to chronic neuropathic pain in up to 50% of patients and is responsible for an impaired quality of life. Intercostal nerve injury has been suggested to be responsible for this pain. In the present study the impact of paravertebral intercostal neurectomy on post thoracotomy pain was assessed. Methods: In this single center parallel-group randomized controlled trial patients underwent muscle sparing anterolateral thoracotomy and anatomical lung resection for lung cancer. A subcostal approach was used for thoracotomy with single paravertebral neurectomy being performed at the beginning of the procedure at the level of the retracted intercostal space. For documentation of neuropathic pain the Leeds Assessment Score for Neuropathic Symptoms and Signs (LANSS) was used postoperatively. The primary endpoint was defined as LANSS ≥12 points on day 120. In addition, the numeric pain rating scale (NRS) was used to score pain intensity. Results: Out of 172 patients initially randomized 161 patients were investigated following intraoperative and postoperative drop-out criteria. All patients required anatomical lung resection via thoracotomy. Five patients were lost for follow up. For the remaining 156 patients there was no difference between the two groups with regard to LANSS ≥12: 26.6 % in patients with neurectomy and 28.8% in control-subjects (P=0.78). In addition, the NSR score at day 120 did not differ significantly at rest and during activity between the two groups (at rest: 21.7% vs . 15.8% P=0.439; activity: 24.5% vs . 21.9% P=0.735). Conclusions: Neurectomy was not shown to reduce the post thoracotomy pain syndrome in patients with anatomical lung resection following anterolateral muscle sparing thoracotomy.

Rationale Although high-intensity non-invasive ventilation (HI-NIV) has been shown to improve outcomes in stable hypercapnic COPD, it may adversely affect cardiac output (CO). Aims: To compare cardiac and pulmonary effects of 6 weeks low-intensity NIV (LI-NIV) and 6 weeks HI-NIV in stable COPD. Design of the study In a randomised crossover study, change in echocardiographically measured CO after 6 weeks of each NIV mode compared to baseline was assessed in 14 stable COPD patients. Furthermore, CO during NIV, gas exchange, lung function, and quality of life were investigated. Results 3 patients dropped out (2 deteriorated on LI-NIV, 1 patient presented with decompensated heart failure based on a coronary artery stenosis; NIV did not affect her CO (baseline 4.3 l/min, under HI-NIV 4.5 l/min)). 11 patients were included for analysis. CO and NTproBNP did not change (change CO: LI-NIV 4% (95% CI -17 to 12) vs. HI-NIV; -3% (-15 to 22); treatment effect HI vs LI: -9% (-27 to 10)). Both modes improved FEV 1 and the Severe Respiratory Insufficiency Summary Score (SRI-SS). HI-NIV tended to improve hypercapnia more. However, changes were not different between HI- and LI-NIV . Conclusion Longer-term NIV does not affect CO, even not with HI-NIV.

Introduction: The human bocavirus (HBoV) is a parvovirus and is associated with mild to life-threatening acute or persisting respiratory infections, frequently accompanied by further pathogens. So far, there is limited knowledge on the mechanisms of persistence, and no reports on chronic infections or latency have been published so far. Case presentation: An immunocompetent male patient suffers from a chronic HBoV1 infection, i.e. viral DNA was detected in both serum and bronchoalveolar lavage (BAL) for >5 months without co-infections and with respiratory symptoms resolved spontaneously while receiving symptomatic treatment with montelukast and corticosteroids. Following the symptomatic medication of a chronic infection with HBoV1 viraemia indicating active viral replication lasting over 5 months, the patient cleared the viraemia and no further viral DNA was detectable in the BAL. However, by fluorescence in situ hybridization analyses of mucosal biopsies, it was shown that the virus genome still persisted in the absence of viral shedding but in a more compact manner possibly representing a supercoiled episomal form of this otherwise linear single-stranded DNA genome. This indicated the entry into a latency phase. Moreover, the cytokine profile and the IP-10/TARC ratio, a marker for fibrotization, seem to have been altered by HBoV1 replication. Although specific IgG antibodies were detectable during the whole observation period, they showed an apparently insufficient neutralising activity. Conclusion: On the one hand, these findings suggest that the symptomatic medication may have led to clearance of the virus from blood and airways and, moreover, that the viral DNA persists in the tissue as an altered episomal form favoured by lacking neutralising antibodies. This appears to be important in order to reduce possible long-term effects such as lung fibrosis.

BACKGROUND: Respiratory insufficiency in COPD may present as hypoxic and/or hypercapnic respiratory failure treated with long-term oxygen therapy (LTOT) and/or noninvasive ventilation (NIV) with LTOT. The Severe Respiratory Insufficiency Questionnaire (SRI) is a tool for the assessment of health-related quality of life (HRQOL) in subjects receiving NIV. However, it remains unclear whether the SRI is also capable of assessing and discriminating HRQOL in subjects receiving LTOT. METHODS: Stable subjects with COPD receiving LTOT or NIV + LTOT (NIV) were prospectively recruited and completed the SRI, lung function tests, and blood gases. Confirmatory factor analysis for construct validity and internal consistency reliability were calculated. RESULTS: One hundred fifty-five subjects were included (113 LTOT, 42 NIV). The Cronbach α coefficient of the 7 subscales ranged between .69 and .89 (LTOT) and between .79 and .93 (NIV), respectively. In both groups, confirmatory factor analysis revealed a one-factor model for the SRI summary scale; in 5 subscales, one- or 2-factor models could be established. Group differences in the SRI subsets were all P

We are grateful to Ulasli and Esquinas for their comments to our paper.. They argued that arterial blood gas analyses were not performed without oxygen prior to the 6-minute walk test with noninvasive ventilation (6MWT-NPPV). This point has already been discussed in our original work by indicating the limitations of our study. The reason for using oxygen prior to exercise testing was to guarantee comparable starting conditions.

Background A large proportion of COPD patients do not achieve the recommended level of physical activity. It is suggested that feedback on the level of activity by using an activity monitoring device (PAM) increases awareness and may stimulate patients to increase their physical activity in daily life. Our objective was to assess the validity and usability of a simple and low-cost physical activity monitor (Polar A300™) when compared with the validated and established Bodymedia-SenseWear™ (SWA) device. Methods To assess the diagnostic equivalent, two different PAM devices were used in parallel in 20 COPD patients GOLD I to IV during 3 consecutive days of daily life. Both systems were compared in terms of steps, calories burned, daily activity time and metabolic equivalents using linear regression analysis and Bland-Altman plots. Practical usability was examined by a 16-item-questionnaire. Results High correlations of both devices were observed with regard to the sensed step count (r = 0.96; p < 0.01) and calories burned (r = 0.74; p < 0.01), and a lower correlation of daily activity (r = 0.25; p < 0.01) was found. Data analysis over 3 days showed that 90% of the steps (95% CI -4223 to 1887), 100% of the calories (95% CI -2798 to 1887), 90% of the daily activity data (95% CI -12.32, 4065) and 95% of the MET (95% CI -3.11 to 2.75) were within the limits of agreement. A favorable usability (system-, information- and interface quality) of the A300™ device was shown (p < 0.01). Conclusion The A300™ device with easy practical usability was shown not to be inferior for assessment of physical activity time, step count and calorie consumption in COPD patients when compared with the SWA. It is suggested to consider widespread available devices as commonly used for monitoring recreational sporting activities also in patients for assessment of physical activity in daily life.

Erkrankungen der Atemorgane treten mit steigendem Alter gehauft auf. Sie nehmen weltweit zu und sind haufige Ursachen fur Morbiditat und Mortalitat. Lungenerkrankungen stehen in der Todesursachenstatistik hinter Krankheiten des Kreislaufsystems und Neubildungen an 3. Stelle. Infektionen der unteren Atemwege, die chronisch obstruktive Lungenerkrankung (COPD), das Bronchialkarzinom und die Tuberkulose gehoren weltweit zu den 10 haufigsten Todesursachen. Asthma ist eine der haufigsten chronischen Krankheiten weltweit; Pravalenz und Morbiditat haben in den letzten Jahren trotz verbesserter Diagnostik und Therapie zugenommen. Durch den Anstieg der Lebenserwartung und Ruckgang der Sterblichkeit wird sich in den nachsten Jahren die Alterspyramide in der deutschen Bevolkerung verandern. Die Altersgruppe uber 60 Jahre wird zahlenmasig deutlich zunehmen. Erkrankungen wie COPD, Bronchialkarzinom und Pneumonie treten uberwiegend in hoheren Altersgruppen auf, Asthma und Tuberkulose dagegen in allen Altersgruppen. Fur die kommenden Jahre wird weltweit eine Zunahme der Pravalenz von Lungenkrankheiten erwartet. Die Krankheitskosten steigen mit dem Alter uberproportional an und die demographischen Veranderungen durften sich somit entscheidend auf das Gesundheitssystem auswirken.

Objective Poor dental status is known to cause infections in severely sick and in elderly patients. In patients awaiting lung transplantation, rigorous dental treatment is a common prerequisite, although evidence-based data are lacking with regard to extent, necessity and effect on post-transplantation infectious status. Materials and Methods In the present retrospective study, dental status [dental history (missing teeth, caries, tooth restorations and extractions, prevalence of periodontitis) and dental treatment prior transplantation] was assessed in 85 lung transplant candidates at the University Hospital of Freiburg, Germany and evaluated for infectious foci in the first 3 years following transplantation. Results Forty-nine patients got transplanted in the observed timespan. Total tooth count differed significantly between chronic obstructive pulmonary disease (16 ± 9), pulmonary fibrosis (22 ± 7) or cystic fibrosis (30 ± 3) patients prior transplantation (P > 0.001). Periodontitis prevalence yielded no difference and was mainly not treated prior transplantation. No dental-related infectious focus could be diagnosed post-transplantation. However, 15% of post-transplantation infections were of unknown focus, and infection rate was increased in year 2 post-transplantation in patients without periodontitis. Conclusion No clearly defined dental foci were registered following transplantation. This raises the question of whether current dental treatment in these highly compromised patients is too rigorous with regard to tooth extractions. However, no focus could be detected in 15% of the registered infections. Therefore, controversially, post-transplantation dental care could also be insufficient with regard to undertreated periodontitis.

The diaphragm was postulated to fatigue relatively early during exhaustive whole body exercise without further loss in contractility as exercise proceeds towards task failure. Diaphragmatic contractility was investigated prior/during/after exhaustive whole body exercise until task failure by using lung volume corrected twitch transdiaphragmatic pressure (TwPdi(c)) during magnetic phrenic nerve stimulation (every 45s). Eleven cyclists exercised to exhaustion (workloads ≥85% maximal oxygen uptake; 20.7±9.8min). Individual post hoc calculation of TwPdi(c) was conducted (diaphragmatic contractility versus lung volume). Diaphragmatic fatigue (i.e. TwPdi reduction baseline/recovery ≥10%) occurred in 9/11 subjects (82% "fatiguers"; baseline/recovery TwPdi(c) -16±13%, p0.01). Fatiguers TwPdi(c) was: baseline: 2.99±0.40kPa, exercise-onset: 2.98±0.41kPa, initial third: 2.80±0.67kPa, second third: 2.54±0.55kPa, final third-task failure: 2.51±0.44kPa, recovery: 2.50±0.52kPa. Diaphragmatic contractility and lung volume (rest) were strongly related (r(2)=0.98, mean TwPdi(c) gradient 0.78kPa/l). To conclude, diaphragmatic contractility (lung volume corrected) decreases relatively early (initial two thirds) during exhaustive exercise and remains preserved towards task failure. This confirms previous assumptions postulating that respiratory performance is sustained without further fatigue of the primary inspiratory muscle.

Patient-centred outcomes are significantly modified by long-term home noninvasive ventilation (NIV), but a short, self-administered, specific tool for routine clinical assessment is lacking. The aim of this study was to develop and validate the S3-NIV questionnaire, a short questionnaire to measure respiratorysymptoms,sleep quality and NIV-relatedside effects.Patients with stable disease who were under long-term home NIV were recruited from three outpatient NIV services. Questionnaire development consisted of a selection of core items for analysis, followed by item reduction, validation and test–retest reliability.338 patients completed a 22-item questionnaire. 11 items were removed because of non-scalability (n=2), redundancy (n=8) and lack of fit (n=1). The final version of the S3-NIV questionnaire consisted of 11 items covering two dimensions: “respiratory symptoms” (Cronbach's α=0.84) and “sleep & NIV-related side effects” (Cronbach's α=0.77). Convergent validity was high between the “respiratory symptoms” subscale of the S3-NIV questionnaire and the St George's Respiratory Questionnaire (rho= −0.76, p3-NIV questionnaire had good test­–retest reliability after 4 weeks (intraclass correlation coefficient=0.72).The S3-NIV questionnaire is a short, valid and repeatable self-completed tool for the routine clinical assessment of patients undergoing home NIV.

Based on externally paced (repetitive) short-term trials exercise-induced diaphragmatic fatigue has been shown to manifest after rather than during exercise. The current study aimed at investigating diaphragmatic contractility and diaphragmatic fatigue during self-paced long-term exhaustive exercise at maximally tolerated loading by the use of supramaximal twitch transdiaphragmatic pressure (TwPdi). Seven trained subjects ( V ˙ O 2 max 63.3 ± 13.9 ml k g − 1 mi n − 1 ) performed self-paced long-term exhaustive exercise at maximally tolerated loading (45 min + endspurt, initial workload 85% V ˙ O 2 max ) followed by recovery (9 min). TwPdi (every 45 s) and ergospirometric data (continuously) were assessed throughout the protocol. Diaphragmatic contractility tended to initially increase during the exercise protocol with a slight decline and final increase during endspurt. Diaphragmatic fatigue manifested only after exercise termination (TwPdi rest 2.6 ± 0.8 kPa; TwPdi exercise start/mid/end 2.9 ± 0.7 kPa vs. 2.6 ± 0.8 kPa vs. 2.4 ± 0.6 kPa; TwPdi endspurt/recovery 2.7 ± 0.8 kPa vs. 1.9 ± 0.6 kPa). In conclusion, diaphragmatic contractility tends to decrease but manifestation of diaphragmatic fatigue is counterbalanced during self-paced long-term exhaustive exercise at maximally tolerated loading.

Zwei voneinander unabhangig limitierbare Anteile bilden das respiratorische System: Lunge und Atempumpe. Die Atempumpe ist ein kompliziertes Organsystem mit unterschiedlichen anatomischen Strukturen: Atemzentrum, peripheres Nervensystem, Atemmuskulatur sowie knocherner Thorax. Entsprechend sind die Moglichkeiten einer gestorten Atempumpfunktion (ventilatorische Insuffizienz) vielfaltig. So konnen neben Atemantriebsstorungen eine Vielzahl von neuromuskularen Erkrankungen, Storungen der Muskelmechanik wie bei Thoraxdeformitaten oder Lungenuberblahung, sowie Atemwegsobstruktionen eine ventilatorische Insuffizienz nach sich ziehen.

Background: Physical activity is known to cause significant deoxygenation in patients with severe chronic obstructive pulmonary disease (COPD). Although noninvasive positive pressure ventilation (NPPV) has been shown to improve oxygenation and physical activity in these patients, no practical approach for the application of NPPV during walking has yet been established. Objective: To elucidate the most effective approach to preserving oxygenation during walking in patients with severe COPD receiving long-term NPPV. Methods: Three 12-min walking tests were performed in a randomized cross-over design on 3 consecutive days, comparing the usual and double dosages of oxygen versus NPPV plus the usual dosage of oxygen. The ventilator and oxygen tank were placed in a backpack. Results: Eleven patients (FEV1 26 ± 9% predicted) completed the study, while 8 patients refused to walk with NPPV, due to the weight of the ventilatory device (7.3 kg with NPPV vs. 3.1 kg without). PaO2 changes during walking differed [p = 0.01, repeated-measures (RM)-ANOVA], whereas dyspnea was unchanged. The difference in PaO2 change was 14.0 ± 16.6 mm Hg (unadjusted p = 0.0036, critical level = 0.017, RM-ANOVA) in favor of NPPV compared to the usual dosage of oxygen. Changes in FEV1, tidal volume and inspiratory impedance were in favor of NPPV-aided exercise (all p < 0.05, RM-ANOVA). Walking distance was reduced under NPPV (555 ± 227 m) compared to the usual (619 ± 210 m) and double (622 ± 215 m) dosages of oxygen (p = 0.024, RM-ANOVA). Conclusions: NPPV plus supplemental oxygen, but not oxygen alone, preserves oxygenation during walking in patients with severe COPD. However, dyspnea and walking distance were not improved due to the burden of carrying the heavy ventilatory equipment in a backpack.

Background: Exercise-induced diaphragmatic fatigue (DF) is conventionally considered to reflect impaired diaphragm function resulting from load imposed on the diaphragm during exercise and is known to be reduced by the application of non-invasive ventilation (NIV) during heavy-intensity exercise testing (HEET). On that physiological condition NIV applied for diaphragm unloading during recovery from exercise should be capable of accelerating recovery from DF and therewith prolonging exercise time to exhaustion and limiting the development of DF during a subsequent HEET compared to recovery during spontaneous breathing. Methods: Seven highly-trained subjects (V’O2max 62.7±7.8 ml/kg/min) performed four HEET at 85% V’O2max with 60 min of recovery during I spontaneous breathing and II NIV between two HEET. Results: Twitch transdiaphragmatic pressure (TwPdi) during supramaximal magnetic phrenic nerve stimulation decreased (p0.2) during I and II. Following second HEET TwPdi comparably decreased (I 0.24±0.21 vs II 0.32±0.29 kPa; p=0.17). Exercise time to exhaustion during second HEET was equal during I and II (I 514±49 vs II 511±92 s; p=0.88). Conclusions: In conclusion, NIV applied for diaphragm unloading during recovery following HEET does neither affect recovery from DF nor subsequent exercise performance thereby providing further evidence that DF might reflect post-exercise diaphragm shielding rather than impaired diaphragm function.

Objectives The Severe Respiratory Insufficiency (SRI) Questionnaire has recently been developed and validated for the assessment of health-related quality of life (HRQL) in patients with severe chronic respiratory failure resulting from a broad spectrum of underlying disorders. The present study was aimed at reexamining the internal structure of the SRI specifically for chronic obstructive pulmonary disease (COPD) patients. Study Design and Setting Cross-validation was performed in two COPD groups ( N = 78 and N = 84), each receiving home mechanical ventilation in addition to long-term oxygen therapy. The internal consistency reliability was calculated using Cronbach's α coefficient. Explorative Factor Analysis was performed followed by Confirmatory Factor Analysis to establish construct validity. Results In the total group ( N = 162) Cronbach's α ranged from 0.73 to 0.88. Only one factor could be established which explained 58.5% of the total variance confirming one Summary Scale (SRI-SS). For each of the seven subscales, Confirmatory Factor Analysis revealed two factors, which were substantially correlated ( r = 0.43–0.80). All scale scores covered a broad range of the questionnaire's scaling range (0–100). The mean SRI-SS score was 52 ± 17 indicating a homogenous scaling distribution. Conclusion The SRI is a multidimensional and highly specific tool with high psychometric properties for HRQL assessment in COPD patients with severe chronic respiratory failure.

Human Bocavirus subtype 1 (HBoV1) is associated with respiratory diseases and may contribute to chronic lung diseases by persisting in the infected host. Here the question was addressed if HBoV infections could contribute to fibrogenesis processes as suggested by previously published clinical observations. Cytokine profiles induced by HBoV infection in CuFi-8 air-liquid interphase cell cultures and in bronchoalveolar lavage fluid (BALF) of 20 HBoV-positive and 12 HBoV-negative patients were analysed by semi-quantitative Western spot blot analyses. Although lots of cytokines were regulated independently of HBoV status, several cytokines associated with lung fibrosis and tumour development, e.g., EGF, VEGF, TARC (CCL17), TNF-α, TNF-β, TIMP-1, were clearly upregulated in the HBoV-positive cohort. These findings suggest that the development of lung fibrosis might be triggered by HBoV induced cytokine expression.

Aims/hypothesis Diabetes has a major negative effect on intensive care unit outcome. This has been partly attributed to impaired respiratory neuromuscular function. However, data on respiratory neuromuscular involvement in diabetes are lacking. This study therefore aimed to assess respiratory neuromuscular function related to diabetic polyneuropathy in patients with type 2 diabetes. Methods Respiratory neuromuscular function was assessed by the use of volitional tests and twitch mouth (TwPmo) and twitch transdiaphragmatic (TwPdi) pressures during non-volitional bilateral anterior magnetic phrenic nerve stimulation in 21 male type 2 diabetic patients without pulmonary disease and in 23 healthy, well-matched controls (forced expiratory volume in 1 s 103±11 vs 103±12% predicted; p=0.9). Results Both volitionally assessed maximal inspiratory and expiratory mouth pressures, and sniff nasal and transdiaphragmatic pressures were comparable between diabetic patients and controls (p>0.1 for all). TwPmo was reduced in diabetic patients compared with controls (1.3±0.5 vs 1.0± 0.4 kPa; p=0.04), while TwPdi was comparable (1.7±0.5 vs 1.6±0.7 kPa; p=0.6). Following subgroup analysis, patients with no or mild polyneuropathy (n=10) as assessed by neurological disability scoring had normal respiratory neuromuscular function, whereas patients with moderate or severe polyneuropathy (n=11) presented with markedly impaired respiratory neuromuscular function as indicated by TwPmo (1.3±0.4 vs 0.8±0.3 kPa; p=0.01) and TwPdi (1.9±0.6 vs 1.1±0.4 kPa; p

Background and objectives: Current international consensus guidelines identify a number of indicators for the establishment of home mechanical ventilation (HMV) for patients with neuromuscular diseases but do not address the possible clinical differences between each of the underlying disorders. This study assessed the differences in the physiological parameters of patients with neuromuscular disease commenced on HMV for the treatment of symptomatic chronic hypercapnic respiratory failure. Methods: Patients commenced on HMV for the treatment of symptomatic chronic hypercapnic respiratory failure over a 9-year period were studied. Physiological parameters at the time of referral for HMV, impact of HMV and survival were analysed. Results: The study recruited 66 patients with neuromuscular disease. Thirty-one patients had rapidly progressive disease: amyotrophic lateral sclerosis (ALS, n = 19), Duchenne muscular dystrophy (DMD, n = 12) and 35 patients had slowly progressive disease. Mean FVC at HMV onset was 40.3 ± 17.5% predicted in all patients, but was >50% predicted in eight patients (12%). ALS patients were more hypercapnic (P = 0.03) and more hypoxaemic (P

Staging criteria for COPD (chronic obstructive pulmonary disease) include symptoms and lung function parameters, but the role of reduced inspiratory muscle strength related to disease severity remains unclear. Therefore the present study tested whether inspiratory muscle strength is reduced in COPD and is related to disease severity according to GOLD (Global Initiative for Chronic Obstructive Lung Disease) criteria and assessed its clinical impact. PImax (maximal inspiratory mouth occlusion pressure), SnPna (sniff nasal pressure) and TwPmo (twitch mouth pressure) following bilateral anterior magnetic phrenic nerve stimulation were assessed in 33 COPD patients (8 GOLD0, 6 GOLDI, 6 GOLDII, 7 GOLDIII and 6 GOLDIV) and in 28 matched controls. Furthermore, all participants performed a standardized 6 min walking test. In comparison with controls, PImax (11.6±2.5 compared with 7.3±3.0 kPa; P0.57; P

Assessing respiratory muscle function has become more and more essential both in clinical research and in the broad field of respiratory and intensive care medicine. In clinical practice, the assessment of respiratory muscle function is useful for differential diagnosis, for the quantification of respiratory muscle impairment and for follow-up assessments, for example, following respiratory muscle training or mechanical ventilation. Both volitional tests on respiratory muscle function, which are dependent on the patient making a truly maximal effort, and non-volitional tests exist. Non-invasive, less complex and most often volitional tests are suitable for screening. However, in case of pathological results these tests need to be complemented by the application of more complex, non-volitional and finally invasive techniques. This is particularly true if the cut-off value indicating no impairment is not achieved by the patient. In this case non-volitional tests are required in order to exclude pathological values resulting from sub-maximal efforts during volitional tests. In addition, isolated respiratory muscle impairments (e. g., solely diaphragmatic) might escape notice in certain tests on respiratory muscle function. For this reason, a diagnostic approach with the application of a combination of different tests should be chosen in those cases where respiratory muscle impairment is suspected. This current "state of the art" article gives a detailed description and comparative evaluation of the different volitional and non-volitional tests that are used for the assessment of respiratory muscle function.

Patients with COPD and chronic hypercapnic respiratory failure (CHRF) are at high risk, and noninvasive ventilation at home is increasingly being used. Knowledge of prognostic parameters under these conditions is limited but may be clinically helpful and highlight the role of noninvasive ventilation.In 188 patients with COPD (mean +/- SD FEV1, 31.0 +/- 9.6% of predicted; PaCo2, 56.3 +/- 9.4 mm Hg) discharged from the hospital receiving NIV between July 1994 and July 2004, the prognostic value of body mass index (BMI), lung function, laboratory parameters, and blood gas levels was assessed by univariate and multivariate Cox regression analyses. Moreover, the impact of changes in risk factors on mortality assessed 6.7 +/- 2.8 months after the initiation of noninvasive ventilation was evaluated.Overall, the mortality rate during follow-up (duration, 32.2 +/- 24.3 months) was 44.7%, with 1-year, 2-year, and 5-year survival rates of 84.0%, 65.3%, and 26.4%. Deaths resulted predominantly from respiratory causes (73.8%). Univariate regression analyses revealed age, BMI, hemoglobin, FEV1, specific airway resistance, residual volume (RV)/total lung capacity (TLC), pH, and base excess (BE) to be associated with prognosis (p0.01 each), whereas multivariate analysis identified only age, BMI, RV/TLC, and BE as independent predictors (p0.05). In patients at risk (BMI25 km/m2, RV/TLCor= 73%, or BEor= 9 mmol/L), changes in these predictors were also associated with survival.In patients with COPD and CHRF, nutritional status, hyperinflation, and BE, which turned out to be reliable and consistent markers in CHRF, were independent prognostic factors for mortality. These data favor a multidimensional approach in these patients, including the use of noninvasive ventilation.

Purpose of reviewTo summarize and discuss the available studies on the effects of long-term noninvasive ventilation (NIV) on cardiac function in patients with chronic hypercapnic respiratory failure.Recent findingsA total of nine studies investigated the acute and long-term effects of NIV on cardiac performance in patients with chronic hypercapnic respiratory failure.SummaryBoth the application of expiratory airway pressure and (higher) inspiratory pressures may acutely decrease cardiac output during the initiation of NIV. However, the meaning of this effect in the long term is not clear. Apparently, natriuretic peptides decrease after a certain period of NIV use and heart rate variability seems to improve. Probably, a decreased cardiac output might not be disadvantageous and reflects a decreased work of breathing. Furthermore, the hemodynamic effects of long-term NIV are dependent on the underlying cardiac comorbidities. This is important in patients with chronic obstructive pulmonary disease, where cardiac comorbidities are frequent.Considering the available physiological data, future studies should focus on the impact of long-term NIV on heart performance and clinical outcomes. Second, further studies are needed investigating the cardiac long-term effects of different NIV modes, pressures (low and high) and breathing frequencies, especially when underlying cardiac comorbidity is present.

During relaxed breathing expiration can be compared to a RC-circuit with R being the airway resistance, C the respiratory system compliance and τ = R∙C the expiratory time constant. For the adult respiratory system, the normal τ is around 0.8 s. Different lung pathologies have different time constants. Two common disease types are the acute respiratory distress syndrome (ARDS) and the chronic obstructive pulmonary disease (COPD). ARDS is characterized by stiff or noncompliant lungs with low compliance and normal or lower resistance which results in shorter τ. COPD is characterized by impaired airflow or high airways resistance and high compliance which results higher τ. τ reveals information about respiratory mechanics and the time required for the lungs to empty. Traditional pulmonary function tests provide global information only. EIT is a non-invasive real-time imaging technology which determines changes of lung volumes on a regional basis assuming that local impedance changes are proportional to local changes in lung volume. Pikkemaat [1] introduced the method to calculate regional τ, what we improved and applied in 10 patients.

Electrical impedance tomography (EIT) is a novel method to monitor regional lung function. For this purpose, 32 surface electrodes are placed around the human thorax. Weak alternating currents are applied via two of these electrodes and the resulting potentials are measured at the remaining electrodes. From the measured voltages, real-time images are calculated which show the distribution of electrical impedance within the body representing functions rather than structures. Using EIT these lungs can be analysed on a regional basis with respect to the following risk factors: collapse, at risk of becoming atelectatic or overdistension. Identifying these lung areas of particular clinical relevance by EIT may help to find the best individual PEEP level for each patient.

Introduction: Gas exchange monitoring in patients undergoing weaning from mechanical ventilation (MV) is essential and a continuous-noninvasive method is desirable. Aims and Objectives: Method comparison of PCO 2 between gold standard ABG and noninvasive PCO 2 -assessment via end-tidal PCO 2 - (PetCO 2 ) and transcutaneous PCO 2 -monitoring (PtcCO 2 ) in tracheostomized patients during invasive MV. Methods: PetCO 2 and PtcCO 2 was monitored over a period of 60min during MV. PaCO 2 -analysis was performed at beginning, at 30min and 60min. Method comparison by Bland and Altman was performed: PetCO 2 versus PaCO 2, PtcCO 2 versus PaCO 2 and PetCO 2 versus PtcCO 2. Results: 62 patients were included and 60 completed the study with the following underlying diseases: COPD (n=30), neurological/neuromuscular (n=17), OHS (n=5), congestive heart failure (n=4), pneumonia (n=3) and kyphoskoliosis (n=1). Mean PaCO 2 was 42,4±8,6 mmHg, PetCO 2 36,5±7,5 mmHg and PtcCO 2 41,7±8,7 mmHg during 60min of MV. Bland and Altman method comparison is shown in Table. Conclusions: Both noninvasive methods of PCO 2 -measurements can not completely substitute PaCO 2 measurements in patients undergoing weaning from MV. However, PtcCO2 showed more favorable results in method comparison to the gold standard PaCO 2 compared to PetCO 2 . Following, transcutaneous but not end-tidal analysis of gas exchange is suggested to be an appropriate surrogate for AGB.

There is an ongoing discussion on whether long-term non-invasive positive pressure ventilation (NPPV) should be used in chronic hypercapnic chronic obstructive pulmonary disease (COPD) patients. Early trials had failed to show convincing physiological and clinical effects using NPPV with assisted modes of ventilation and rather low inflation pressures. In particular, long-term survival could not be improved and findings on health-related quality of life had been conflicting. Remarkably, high-intensity NPPV using higher inflation pressures and back-up rates has recently been shown to be capable of improving blood gases, lung function, and health-related quality of life. Subsequently, a large study using this technique also showed a substantial improvement in the prognosis in these patients. Therefore, there is now increasing evidence to support physiologically effective NPPV in hypercapnic COPD patients, but how to best select patients still needs to be defined. The present article summarizes the physiological background and the current evidence on NPPV in COPD in addition to future considerations.

Budweiser S, Moertl M, Jorres RA, Windisch W, Heinemann F, Pfeifer M. Respiratory muscle training in restrictive thoracic disease: a randomized controlled trial. Objective To investigate the effects of respiratory muscle training (RMT) in patients with restrictive thoracic disorders and intermittent noninvasive positive-pressure ventilation (NPPV). Design Prospective randomized controlled trial. Setting Home-based RMT, with assessment in a primary care pulmonary center. Participants Thirty patients with restrictive thoracic disorders; 28 patients completed the trial. Intervention Three months of RMT by isocapnic hyperpnea or sham training. Main Outcome Measures Respiratory muscle strength and endurance, lung function, exercise performance, and health-related quality of life (HRQOL). Results After RMT, maximal inspiratory mouth pressure was increased (27.6%±36.5%, P =.013). In patients who could perform cycle ergometer testing (n=17), peak oxygen consumption (2.24±3.39mL·kg −1 ·min −1 vs −1.71±2.54mL·kg −1 ·min −1 , P =.014) and maximal work rate (9.4±14.8W vs −5.1±10.8W, P =.043) increased relative to a control group. Similar differences occurred regarding changes of HRQOL (physical performance, 3.3±11.4 score vs −6.6±9.0 score; P =.012) and time of ventilator use (−0.6±1.2h/d vs 0.4±0.5h/d, P =.010). Lung volumes, 12-second maximum voluntary ventilation, 6-minute walking distance, and blood gases were unchanged. Conclusions In patients with restrictive thoracic disorders and NPPV, RMT improved inspiratory muscle strength. Exercise performance and HRQOL were improved when the 2 groups were compared. RMT was practicable and safe despite severe respiratory impairment. Further evaluation, including different training intensities and modalities, seems warranted.

Objetivo La ventilacion mecanica domiciliaria se aplica a pacientes con insuficiencia respiratoria cronica y grave, lo que tiene un impacto considerable en su calidad de vida. El objetivo de este trabajo ha sido realizar una traduccion y adaptacion transcultural para la poblacion espanola del cuestionario Severe Respiratory Insuficiency (SRI), el primer cuestionario de calidad de vida relacionada con la salud especifico para estos pacientes. Metodos Intervinieron 4 traductores bilingues aleman-espanol siguiendo el metodo de la traduccion y retrotraduccion. Despues de cada paso se realizaron reuniones con los traductores para obtener una version unica antes de continuar. Al final del proceso se realizo una prueba piloto para valorar su comprensibilidad. El proceso de traduccion se evaluo en dificultad y naturalidad, mediante una escala entre 1 (minimo) y 10 (maximo), asi como en equivalencia de los items con la version original. Resultados Se obtuvieron 3 versiones en espanol. La dificultad de la traduccion fue considerablemente baja para la traduccion (media ± desviacion estandar 1,4 ± 0,6) y la retrotraduccion (2,2 ± 1,1). La naturalidad de los items fue muy elevada y mejoro con las sucesivas versiones (version 1: 8,4; version 2: 8,7; version 3: 9,1; p Conclusiones La traduccion del cuestionario siguiendo el metodo de la traduccion-retrotraduccion ha dado una version espanola equiparable a la original y asequible para los pacientes. Actualmente se esta llevando a cabo la validacion del cuestionario mediante un estudio multicentrico.

Background Average volume-assured pressure support (AVAPS) has been introduced as a new additional mode for a bilevel pressure ventilation (BPV) device (BiPAP; Respironics; Murrysville, PA), but studies on the physiologic and clinical effects have not yet been performed. There is a particular need to better define the most efficient ventilatory treatment modality for patients with obesity hypoventilation syndrome (OHS). Methods In OHS patients who did not respond to therapy with continuous positive airway pressure, the effects of BPV with the spontaneous/timed (S/T) ventilation mode with and without AVAPS over 6 weeks on ventilation pattern, gas exchange, sleep quality, and health-related quality of life (HRQL) assessed by the severe respiratory insufficiency questionnaire (SRI) were prospectively investigated in a randomized crossover trial. Results Ten patients (mean [± SD] age, 53.5 ± 11.7 years; mean body mass index, 41.6 ± 12.1 kg/m 2 ; mean FEV 1 /FVC ratio, 79.4 ± 6.5%; mean transcutaneous P co 2 [Ptc co 2 ], 58 ± 12 mm Hg) were studied. Ptc co 2 nonsignificantly decreased during nocturnal BPV-S/T by −5.6 ± 11.8 mm Hg (95% confidence interval [CI], −14.7 to 3.4 mm Hg; p = 0.188), but significantly decreased during BPV-S/T-AVAPS by −12.6 ± 12.2 mm Hg (95% CI, −22.0 to −3.2 mm Hg; p = 0.015). Pneumotachographic measurements revealed a higher individual variance of peak inspiratory pressure (p Conclusion BPV-S/T substantially improved oxygenation, sleep quality, and HRQL in patients with OHS. AVAPS provided additional benefits on ventilation quality, thus resulting in a more efficient decrease of Ptc co 2 . However, this did not provide further clinical benefits regarding sleep quality and HRQL.

The trigger has a key role when assessing the twitch mouth pressure (Tw Pmo), since a "gentle" inspiratory or expiratory effort is needed for triggering to ensure an open glottis during twitch, but which also guarantees only very mild changes of transdiaphragmatic pressure following changes in lung volume.To test if different trigger mechanisms cause different Tw Pmo values, if the predefined trigger criteria were accomplished, and if the breathing maneuver during triggering can influence the Tw Pmo.Experimental study.Respiratory muscle and lung function laboratory of a university hospital.Twenty healthy men (mean age, 25.6 +/- 1.2 years [+/- SD]; mean FEV(1), 105.9 +/- 11.5% of predicted).Tw Pmo produced by bilateral anterior magnetic phrenic nerve stimulation was measured using an inspiratory flow trigger (40 mL/s), an inspiratory pressure trigger, and an expiratory pressure trigger (3.75 mm Hg). All trigger criteria were controlled.Unusable pressure-time curves occurred in 40% during expiratory triggering, but not during inspiratory triggering. For inspiratory pressure (flow) triggering, 10% (30%) of the predefined trigger criteria were exceeded by 50%, indicating that a "gentle" inspiratory effort was not warranted. The Tw Pmo was higher during inspiratory compared to expiratory triggering (analysis of variance, p0.05). The Tw Pmo during inspiratory pressure and flow triggering were comparable and significantly correlated (r = 0.70, p0.0001). The time between start of inspiration and trigger release, and the pressure-time product during that period ranged widely, but this could not predict the Tw Pmo (multiple linear regression).The trigger technique influences the Tw Pmo with higher values during inspiratory compared to expiratory triggering. Expiratory triggering more often produced unusable pressure-time curves. Inspiratory flow and pressure triggering is comparably useful in healthy subjects, but this might be different in patients. The trigger criteria need to be controlled to warrant a gentle breathing effort.

Both pressure- and volume-limited non-invasive positive pressure ventilation (NPPV) have been used in patients with chronic respiratory failure. The aim of the present study was to compare the efficacy of ventilation during nocturnal volume- and pressure-limited NPPV.Fifteen patients (nine COPD, six non-COPD) were randomly assigned to receive either volume-limited or pressure-limited NPPV and were switched to the complementary mode after 6 weeks.Ten patients (five COPD, five non-COPD) completed the study. PaCO2 during sleep comparably decreased from 54.6±8.0 to 46.2±6.1mmHg during volume-limited NPPV (P

We report two confirmed cases of usual interstitial pneumonia (UIP) associated with infection of the human bocavirus (HBoV). In one case HBoV was identified in the bronchoalveolar lavage (BAL) during an acute exacerbation as well as post mortem in different tissues giving raise to the hypothesis that HBoV infections trigger UIP or could be a causative agent and be a systemic component in UIP. In the other case, the UIP was confirmed by radiological methods and HBoV was detected in the BAL during an acute exacerbation. Both cases give raise to the hypothesis that HBoV could be a causative agent of UIP or could contribute to its development and/or acute exacerbations.

Inosine is an endogenous purine nucleoside, which is formed by adenosine deaminidase during adenosine breakdown and is released into the extracellular space from the sympathetic nervous system or injured cells. Here, we studied the biological activity of inosine on human dendritic cells (DC), which are specialized antigen presenting cells characterized by their ability to migrate from the blood to peripheral tissues, and then to secondary lymphoid organs where they initiate adaptive immune responses. In immature DC, inosine concentration-dependently stimulated Ca2+-transients, actin polymerization, and chemotaxis. Experiments with adenosine receptor antagonists and pertussis toxin (PTX) as well as desensitization studies suggested that the activity of inosine was mediated by a G protein-coupled receptor pathway independent of adenosine receptors. DC, induced to mature by lipopolysaccharide, lost their ability to respond towards inosine with these activities. Moreover, inosine did neither influence membrane expression of CD54, CD80, CD83, CD86, HLA-DR, and MHC class I molecules nor modulated secretion of interleukin (IL)-12, IL-10, and tumor necrosis factor alpha in immature and lipopolysaccharide-matured DC. In aggregate, our study indicates that inosine may be involved in the trafficking control system of immature DC, and mediates its chemotactic activity by a PTX-sensitive mechanism independent of adenosine receptors. J. Cell. Physiol. 199: 149–156, 2004© 2003 Wiley-Liss, Inc.

The objective of this study was to develop a specific instrument for measuring health-related quality of life (HRQL) in patients receiving home mechanical ventilation (HMV).The Severe Respiratory Insufficiency (SRI) Questionnaire was developed and tested for its psychometric properties following a multicentric clinical trial including 226 patients receiving HMV (mean age 57.3+/-14.0 years).Forty-nine items passed the selection process and were allocated to seven subscales: Respiratory Complaints, Physical Functioning, Attendant Symptoms and Sleep, Social Relationships, Anxiety, Psychologic Well-Being, and Social Functioning. Cronbach's alpha was0.7 in all subscales and0.8 in four subscales indicating high internal consistency reliability. Construct validity was confirmed by factor analysis, indicating one summary scale that accounts for 59.8% of the variance. Concurrent validity was confirmed by correlating subscales of the SRI and the SF-36 (0.21r0.79). Item-scale correlations revealed a high item discriminant validity. In addition, different diagnostic groups could be discriminated by the SRI. Here, the overall best HRQL was measured in the following order: patients with kyphoscoliosis, miscellaneous disorders, neuromuscular diseases, post-tuberculosis, and chronic obstructive pulmonary disease (P.05).The SRI is a new multidimensional instrument with high psychometric properties designed to measure specific HRQL in patients with SRI receiving HMV.