Inspiratory Muscle Dysfunction Mediates and Predicts a Disease Continuum of Hypercapnic Failure in Chronic Obstructive Pulmonary Disease.

INTRODUCTION: Advanced chronic obstructive pulmonary disease (COPD) is associated with chronic hypercapnic failure. The present work aimed to comprehensively investigate inspiratory muscle function as a potential key determinant of hypercapnic respiratory failure in patients with COPD. METHODS: Prospective patient recruitment encompassed 61 stable subjects with COPD across different stages of respiratory failure, ranging from normocapnia to isolated nighttime hypercapnia and daytime hypercapnia. Arterialized blood gas analyses and overnight transcutaneous capnometry were used for patient stratification. Assessment of respiratory muscle function encompassed body plethysmography, maximum inspiratory pressure (MIP), diaphragm ultrasound, and transdiaphragmatic pressure recordings following cervical magnetic stimulation of the phrenic nerves (twPdi) and a maximum sniff manoeuvre (Sniff Pdi). RESULTS: Twenty patients showed no hypercapnia, 10 had isolated nocturnal hypercapnia, and 31 had daytime hypercapnia. Body plethysmography clearly distinguished patients with and without hypercapnia but did not discriminate patients with isolated nocturnal hypercapnia from those with daytime hypercapnia. In contrast to ultrasound parameters and transdiaphragmatic pressures, only MIP reflected the extent of hypercapnia across all three stages. MIP values below -48 cmH2O predicted nocturnal hypercapnia (area under the curve = 0.733, p = 0.052). CONCLUSION: In COPD, inspiratory muscle dysfunction contributes to progressive hypercapnic failure. In contrast to invasive tests of diaphragm strength only MIP fully reflects the pathophysiological continuum of hypercapnic failure and predicts isolated nocturnal hypercapnia.

[Prognostic factors in an individualised approach to non-pharmacological therapy of COVID-19: from oxygen and mechanical ventilation to extracorporeal membrane oxygenation]. / Prognostische Faktoren bei einem schrittweisen Ansatz zur nicht-pharmakologischen Therapie von Sauerstoff und mechanischer Beatmung bis hin zur extrakorporalen Membranoxygenierung bei COVID-19.

BACKGROUND: Our centre followed a stepwise approach in the nonpharmacological treatment of respiratory failure in COVID-19 in accordance with German national guidelines, escalating non-invasive measures before invasive mechanical ventilation (IMV) or extracorporeal membrane oxygenation (ECMO). The aim of this study was to analyse this individualized approach to non-pharmacologic therapy in terms of patient characteristics and clinical features that may help predict more severe disease, particularly the need for intensive care. METHOD: This retrospective single-centre study of COVID-19 inpatients between March 2020 and December 2021 analysed anthropometric data, non-pharmacological maximum therapy and survival status via a manual medical file review. RESULTS: Of 1052 COVID-19-related admissions, 835 patients were included in the analysis cohort (54% male, median 58 years); 34% (n=284) received no therapy, 40% (n=337) conventional oxygen therapy (COT), 3% (n=22) high flow nasal cannula (NHFC), 9% (n=73) continuous positive airway pressure (CPAP), 7% (n=56) non-invasive ventilation (NIV), 4% (n=34) intermittent mandatory ventilation (IMV), and 3% (n=29) extracorporeal membrane oxygenation (ECMO). Of 551 patients treated with at least COT, 12.3% required intubation. A total of 183 patients required ICU treatment, and 106 (13%) died. 25 (74%) IMV patients and 23 (79%) ECMO patients died. Arterial hypertension, diabetes and dyslipidemia was more prevalent in non-survivors. Binary logistic analysis revealed the following risk factors for increased mortality: an oxygen supplementation of ≥2 L/min at baseline (OR 6.96 [4.01-12.08]), age (OR 1.09 [1.05-1.14]), and male sex (OR 2.23 [0.79-6.31]). CONCLUSION: The physician's immediate clinical decision to provide oxygen therapy, along with other recognized risk factors, plays an important role in predicting the severity of the disease course and thus aiding in the management of COVID-19.

Analysis of an Individualised Stepwise Approach to Non-Pharmacological Therapy in COVID-19.

BACKGROUND: Early intubation versus use of conventional or high-flow nasal cannula oxygen therapy (COT/HFNC), continuous positive airway pressure (CPAP), and non-invasive ventilation (NIV) has been debated throughout the COVID-19 pandemic. Our centre followed a stepwise approach, in concordance with German national guidelines, escalating non-invasive modalities prior to invasive mechanical ventilation (IMV) or extracorporeal membrane oxygenation (ECMO), rather than early or late intubation. OBJECTIVES: The aims of the study were to investigate the real-life usage of these modalities and analyse patient characteristics and survival. METHOD: A retrospective monocentric observation was conducted of all consecutive COVID-19 hospital admissions between March 2020 and December 2021 at a university-affiliated pulmonary centre in Germany. Anthropometric data, therapy, and survival status were descriptively analysed. RESULTS: From 1,052 COVID-19-related admissions, 835 patients were included (54% male, median 58 years). Maximum therapy was as follows: 34% (n = 284) no therapy, 40% (n = 337) COT, 3% (n = 22) HFNC, 9% (n = 73) CPAP, 7% (n = 56) NIV, 4% (n = 34) IMV, and 3% (n = 29) ECMO. Of 551 patients treated with at least COT, 12.3% required intubation. Overall, 183 patients required intensive unit care, and 106 (13%) died. Of the 68 patients who received IMV/ECMO, 48 died (74%). The strategy for non-pharmacological therapy was individual but remained consistent throughout the studied period. CONCLUSIONS: This study provides valuable insight into COVID-19 care in Germany and shows how the majority of patients could be treated with the maximum treatment required according to disease severity following the national algorithm. Escalation of therapy modality is interlinked with disease severity and thus associated with mortality.

Bronchoscopic Brushing from Central Lung Cancer-Next Generation Sequencing Results are Reliable.

The role of bronchoscopic brushing for tumor detection and molecular testing in central lung cancer is unclear. In this study, 50 consecutive subjects with suspected central lung cancer underwent bronchoscopic brushing (31 males, median age 70, 5 never smokers). Histological results were: NSCLC/SCLC/low-grade-NET/granulation tissue in 36/8/2/4 cases. Next generation sequencing (NGS) was feasible in 62% of tumor-positive brush smear samples. In 78% of these cases, NGS displayed identical results compared to histology samples, in 22% NGS from brush smears detected specific mutations, whereas DNA quality from forceps biopsy was insufficient for NGS analysis. Sensitivity, specificity, positive predictive value, negative predictive value of brush smear analysis were 66% (95% confidence interval 50-79), 100% (40-100), 100% (85-100), and 21% (7-46). For the combined analysis of brush smear, brush tip washing and sheath tube content sensitivity was slightly elevated at 69% (53-81). In central lung cancer, bronchoscopic brushing detects tumor cells in about two-third of cases and allows a decision for or against targeted therapy in the majority of tumor-positive cases on the basis of NGS analysis.

Comparing Azole Plasma Trough Levels in Lung Transplant Recipients: Percentage of Therapeutic Levels and Intrapatient Variability.

BACKGROUND: This study compared therapeutic azole plasma trough levels (APL) of the azole antimycotics itraconazole (ITR), voriconazole (VOR), and posaconazole (POS) in lung transplant recipients and analyzed the influencing factors. In addition, intrapatient variability for each azole was determined. METHODS: From July 2012 to July 2015, 806 APL of ITR, VOR, posaconazole liquid (POS-Liq), and posaconazole tablets (POS-Tab) were measured in 173 patients of the Munich Lung Transplantation Program. Therapeutic APL were defined as follows: ITR, ≥700 ng/mL; VOR, 1000-5500 ng/mL; and POS, ≥700 ng/mL (prophylaxis) and ≥1000 ng/mL (therapy). RESULTS: VOR and POS-Tab reached the highest number of therapeutic APL, whereas POS-Liq showed the lowest percentage (therapy: ITR 50%, VOR 70%, POS-Liq 38%, and POS-Tab 82%; prophylaxis: ITR 62%, VOR 85%, POS-Liq 49%, and POS-Tab 76%). Risk factors for subtherapeutic APL of all azoles were the azole dose (ITR, P < 0.001; VOR, P = 0.002; POS-Liq, P = 0.006) and age over 60 years (ITR, P = 0.003; VOR, P = 0.002; POS-Liq, P = 0.039; POS-Tab, P < 0.001). Cystic fibrosis was a significant risk factor for subtherapeutic APL for VOR and POS-Tab (VOR, P = 0.002; POS-Tab, P = 0.005). Double lung transplantation (LTx) was significantly associated with less therapeutic APL for VOR and POS-Liq (VOR, P = 0.030; POS-Liq, P < 0.001). Concomitant therapy with 80 mg pantoprazole led to significantly fewer therapeutic POS APL as compared to 40 mg (POS-Liq, P = 0.015; POS-Tab, P < 0.001). VOR displayed the greatest intrapatient variability (46%), whereas POS-Tab showed the lowest (32%). CONCLUSIONS: Our study showed that VOR and POS-Tab achieve the highest percentage of therapeutic APL in patients with LTx; POS-Tab showed the lowest intrapatient variability. APL are significantly influenced by azole dose, age, cystic fibrosis, type of LTx, and comedication with proton-pump inhibitors. Considering the high number of subtherapeutic APL, therapeutic drug monitoring should be integrated in the post-LTx management.

Suspected pulmonary embolism in patients with pulmonary fibrosis: Discordance between ventilation/perfusion SPECT and CT pulmonary angiography.

BACKGROUND AND OBJECTIVE: Pulmonary embolism (PE) is a common differential diagnosis in patients with pulmonary fibrosis presenting with a clinical deterioration. Both ventilation/perfusion (V/Q)-single photon emission computed tomography (SPECT) and computed tomographic pulmonary angiography (CTPA) are routinely used to detect PE. However, the value of V/Q-SPECT and CTPA in this scenario has not been studied so far. We aimed to investigate the concordance of V/Q-SPECT and CTPA in patients with pulmonary fibrosis and suspicion of pulmonary embolism. METHODS: A total of 22 consecutive patients with pulmonary fibrosis and clinical deterioration who underwent both V/Q-SPECT and CTPA were included in the study and analyzed for the presence of pulmonary embolism. RESULTS: Nine of 22 patients (41%) had evidence for pulmonary embolism in V/Q-SPECT, and two of these patients had matching evidence for pulmonary embolism in CTPA. In the other seven patients with positive findings in V/Q-SPECT, no evidence of pulmonary embolism was found in CTPA. None of the 13 patients with a negative V/Q-SPECT had evidence for pulmonary embolism in CTPA. CONCLUSION: In patients with pulmonary fibrosis and suspected pulmonary embolism, pulmonary embolism is detected more frequently by V/Q-SPECT than by CTPA. Thromboembolic disease is identified on CTPA only in a minority of patients with positive findings on V/Q-SPECT. When making treatment decisions, clinicians should be aware of the high rate of discordant findings in V/Q-SPECT and CTPA in this specific patient population.

From the infant to the geriatric patient-Strategies for inhalation therapy in asthma and chronic obstructive pulmonary disease.

Inhalation therapy represents the standard of care in children, adolescents as well as in young, middle-aged and geriatric adults with asthma or chronic obstructive pulmonary disease. However, there are only few recommendations for the choice of inhalation devices, which consider both, age-specific limitations in young and geriatric patients. Transition concepts are lacking. In this narrative review, the available device technologies and the evidence for age-specific problems are discussed. Pressurized metered-dose inhalers may be favoured in patients who fulfill all cognitive, coordinative and manual power requirements. Breath-actuated metered-dose inhalers, soft-mist inhalers or the use of add-on devices such as spacers, face masks and valved holding chambers may be suitable for patients with mild to moderate impairments of these variables. In these cases, available resources of personal assistance by educated family members or caregivers should be used to allow metered-dose inhaler therapy. Dry powder inhalers may be reserved for patients with a sufficient peak inspiratory flow and good cognitive and manual abilities. Nebulizers may be indicated in persons who are either unwilling or unable to use handheld inhaler devices. After initiation of a specific inhalation therapy, close monitoring is essential to reduce handling mistakes. An algorithm is developed that considers age and relevant comorbidities to support the decision-making process for the choice of an inhaler device.

Assessment of sleep disordered breathing in patients with heart failure.

When to look for sleep disturbances in heart failure patients and how best to treat them: a practical and evidence-based expert opinion https://bit.ly/3LpCnNP.

Severity stages of obesity-related breathing disorders - a cross-sectional cohort study.

INTRODUCTION: There is a general underappreciation of the spectrum of obesity-related breathing disorders and their consequences. We therefore compared characteristics of obese patients with eucapnic obstructive sleep apnea (OSA), OSA with obesity-related sleep hypoventilation (ORSH) or obesity hypoventilation syndrome (OHS) to identify the major determinants of hypoventilation. PATIENTS AND METHODS: In this prospective, diagnostic study (NCT04570540), obese patients with OSA, ORSH or OHS were characterized applying polysomnography with transcutaneous capnometry, blood gas analyses, bodyplethysmography and measurement of hypercapnic ventilatory response (HCVR). Pathophysiological variables known to contribute to hypoventilation and differing significantly between the groups were specified as potential independent variables in a multivariable logistic regression to identify major determinants of hypoventilation. RESULTS: Twenty, 43 and 19 patients were in the OSA, ORSH and OHS group, respectively. BMI was significantly lower in OSA as compared to OHS. The extent of SRBD was significantly higher in OHS as compared to OSA or ORSH. Patients with ORSH or OHS showed a significantly decreased forced expiratory volume in 1 s and forced vital capacity compared to OSA. HCVR was significantly lower in OHS and identified as the major determinant of hypoventilation in a multivariable logistic regression (Nagelkerke R2 = 0.346, p = 0.050, odds ratio (95%-confidence interval) 0.129 (0.017-1.004)). CONCLUSION: Although there were differences in BMI, respiratory mechanics and severity of upper airway obstruction between groups, our data support HCVR as the major determinant of obesity-associated hypoventilation.

High sensitivity of PD-L1 analysis from pleural effusion in nonsmall cell lung cancer.

Background: Programmed cell death protein 1 (PD-1)/programmed cell death protein ligand 1 (PD-L1) immune checkpoint inhibitors have been approved for monotherapy of metastatic nonsmall cell lung cancer (mNSCLC) depending on tumour cells' PD-L1 expression. Pleural effusion is common in mNSCLC. The significance of immunocytochemistry PD-L1 analysis from pleural effusion samples is unclear. Aim: The aim of the study was to analyse the sensitivity regarding immunocytochemistry PD-L1 analysis of pleural effusion in NSCLC as compared to immunohistochemistry of pleural biopsies. Patients and Methods: Fifty consecutive subjects (17 female, median age 72.5 years, seven never-smokers) were enrolled in this prospective controlled two-centre study. Inclusion criteria were pleural effusion, suspected or known lung cancer, indication for pleural puncture and thoracoscopy, and written informed consent. Immunocytochemistry and immunohistochemistry PD-L1 analyses were performed with the Dako-PDL1-IHC-22C3pharmDx assay. Analysis for sensitivity, specificity, and positive and negative predictive value was performed for PD-L1 detection from pleural effusion. Results: 50 subjects underwent pleural puncture and thoracoscopy. Pathological diagnoses were lung cancer (48), lymphoma (1) and mesothelioma (1). Sensitivity, specificity, positive predictive value and negative predictive value of PD-L1-testing with expression ≥50% defined as positive were 100% (95% CI 46-100%), 63% (36-84%), 45% (18-75%) and 100% (66-100%), and with expression ≥1% defined as positive 86% (56-97%), 43% (12-80%), 75% (47-92%) and 60% (17-93%). Conclusion: PD-L1 analysis in tumour-positive pleural effusion samples shows a very high sensitivity and negative predictive value, especially regarding PD-L1 expression levels ≥50% (European Medicines Agency approval). Negative results are reliable and help in the decision against a first-line checkpoint inhibitor monotherapy. However, a 1% cut-off level (United States Food and Drug Administration approval) leads to a markedly lower negative predictive value, making other invasive procedures necessary (NCT02855281).

Combining biopsy tools improves mutation detection rate in central lung cancer.

In central exophytic lung cancer, the detection rate of oncogenic mutations and PDL1 positivity may be increased by combined sampling by forceps and EBUS-TBNA. The additional sampling of mediastinal lymph node and ctDNA may not be of additional benefit. https://bit.ly/2Ve41EF.

Safety and Efficacy of Steroid Pulse Therapy for Acute Loss of FEV1 in Lung Transplant Recipients After Exclusion of Acute Cellular Rejection.

BACKGROUND: The standard treatment of acute cellular rejection after lung transplantation (LTx) is a high-dose steroid pulse therapy. In our center, this therapy is also the standard of care for LTx recipients with acute loss of forced expiratory volume in 1 second (FEV1), after excluding specific causes such as acute rejection on biopsy. The aim of this retrospective study was to evaluate the safety and efficacy of steroid pulse therapy. METHODS: From 2015 to 2018, 33 consecutive patients (17 male patients, mean age ± SD, 50.5 ± 12.5 years) were included. All patients underwent routine examinations to exclude acute cellular rejection and other specific causes. FEV1 was routinely measured after 5 days, and 1, 3, and 6 months. Positive response to steroid pulse therapy was defined by increase of FEV1 > 10%. RESULTS: The mean decrease ± SD from baseline in FEV1 at the start of steroid pulse therapy was 380 ± 630 mL (P = .02). FEV1 changed after 5 days by 170 ± 180 mL (P = .0007), and after 1 month by 140 ± 230 mL (P = .70), 3 months by -60 ± 240 mL (P = .15), and 6 months by -80 ± 290 mL (P = .73). A positive response was observed in 21% of patients after 3 months and 12% after 6 months. High bronchoalveolar lavage (BAL) eosinophil count correlated with a higher FEV1 after steroid pulse therapy. Serious complications were observed in 4 out of 33 patients (12%) with 1 fatal event (pneumonia). CONCLUSIONS: Only a minority of patients after LTx with loss of FEV1 after exclusion of acute cellular rejection benefit from steroid pulse therapy. Patients with BAL eosinophilia are more likely to respond. However, severe complications were observed.

Emergencies and outcome in invasive out-of-hospital ventilation: An observational study over a 1-year period.

OBJECTIVES: The number of ventilated patients is further increasing which leads to an increasing number of patients with weaning failure. In Germany, the treatment of patients with invasive out-of-hospital becomes more and more common. The aim of the study was to observe the outcome, the frequency and character of emergencies of patients with invasive out-of-hospital ventilation. METHODS: We conducted a prospective study over 1 year. Fifty-nine invasively ventilated patients living either at home or at nursing homes specialized in ventilator medicine were included. RESULTS: Forty-one (71%) of the patients were living in a nursing home. Chronic obstructive pulmonary disease (COPD) was the most common underlying disease (52.5%). Duration of daily ventilation did not change over the 1-year period. 52.8% of the months went without a documented emergency. The most common emergencies were oxygen desaturation (29.6%), increase of secretion (12.2%) and dyspnea (8.7%). We found no difference in the frequency of emergencies between patients cared for in their own home compared with residential care. Ten patients died during the observation period. Fewer emergencies (P = .02, CI 0.03-0.85) was the only parameter associated with a reduced mortality. Frequency of emergencies as well as survival showed no difference regarding the way patients were cared for. CONCLUSIONS: In patients with invasive home mechanical ventilation survival for more than 1 year seems to be common. Only the rate of emergencies affected survival.

Asthma features in severe COPD: Identifying treatable traits.

AIM: Biological therapies developed for severe asthma may have a role in COPD patients with asthma features. METHOD: We carried out a prospective, consecutive, cross-sectional analysis of 80 patients with severe COPD GOLD IV/D. RESULTS: We studied 80 patients (48.8% female), aged 57.6 ±â€¯5.1 years, ex-smokers with 35.7 ±â€¯21.2 pack years, BMI 22.3 ±â€¯3.5 kg/m2, FEV1 of 0.61 ±â€¯0.2 L (21.1 ±â€¯5.6% pred), pO2 52.4 ±â€¯8.4 mmHg, and BODE 6.9 ±â€¯1.7. 68% had >2 moderate or severe exacerbations annually. 16.1% (5/31) patients showed FEV1 reversibility of >12% and >200 ml despite maximal therapy, 33% (15/45) had FENO ≥22.5 ppb, 33% (24/73) had serum IgE ≥100 I.E./ml and there was positive allergen sensitization in 51.5% (35/68). Blood eosinophilia of ≥150 cells/µl was seen in 47% (35/74). Induced sputum showed eosinophilia of ≥2% in 56% (14/24) with respiratory pathogens in 63.8% (30/47). We identified 12 (15%) patients with asthma-COPD overlap. Of these, 10 (83.3%) had frequent exacerbations and these patients had significantly more severe exacerbations requiring NIV or ICU than those without asthma features (p < 0.005). CONCLUSION: We detected asthma features in a substantial subset of stable patients with severe COPD. Asthma features were associated with more severe exacerbation despite optimal COPD therapy, representing potential candidates for targeted therapy with anti- IgE or anti-IL5.

Outcome of lung transplantation in idiopathic pulmonary fibrosis with previous anti-fibrotic therapy.

BACKGROUND: Anti-fibrotic drugs may interfere with wound-healing after major surgery, theoretically preventing sufficient bronchial anastomosis formation after lung transplantation (LTx). The aim of this study was to assess the impact of previous treatment with pirfenidone and nintedanib on outcomes after LTx in patients with idiopathic pulmonary fibrosis (IPF). METHODS: All patients with IPF undergoing LTx at the University of Munich between January 2012 and November 2016 were retrospectively screened for previous use of anti-fibrotics. Post-transplant outcome and survival of patients with and without anti-fibrotic treatment were analyzed. RESULTS: A total of 62 patients with IPF were transplanted (lung allocation score [mean ± SD] 53.1 ± 16.1). Of these, 23 (37.1%) received pirfenidone and 7 (11.3%) received nintedanib before LTx; the remaining 32 (51.6%) did not receive any anti-fibrotic drug (control group). Patients receiving anti-fibrotics were significantly older (p = 0.004) and their carbon monoxide diffusion capacity was significantly higher (p = 0.008) than in controls. Previous anti-fibrotic treatment did not increase blood product utilization, wound-healing or anastomotic complications after LTx. Post-transplant surgical revisions due to bleeding and/or impaired wound-healing were necessary in 18 (29.0%) patients (pirfenidone 30.4%, nintedanib 14.3%, control 31.3%; p = 0.66). Anastomosis insufficiency occurred in 2 (3.2%) patients, both in the control group. No patient died within the first 30 days post-LTx, and no significant differences regarding survival were seen during the follow-up (12-month survival: pirfenidone 77.0%, nintedanib 100%, control 90.6%; p = 0.29). CONCLUSION: Our data show that previous use of anti-fibrotic therapy does not increase surgical complications or post-operative mortality after LTx.

Perception of climate change in patients with chronic lung disease.

BACKGROUND: Climate change affects human health. The respective consequences are predicted to increase in the future. Patients with chronic lung disease are particularly vulnerable to the involved environmental alterations. However, their subjective perception and reactions to these alterations remain unknown. METHODS: In this pilot study, we surveyed 172 adult patients who underwent pulmonary rehabilitation and 832 adult tourists without lung disease in the alpine region about their perception of being affected by climate change and their potential reaction to specific consequences. The patients' survey also contained the COPD Assessment Test (CAT) to rate the severity of symptoms. RESULTS: Most of the patients stated asthma (73.8%), COPD (9.3%) or both (11.0%) as underlying disease while 5.8% suffered from other chronic lung diseases. Patients and tourists feel equally affected by current climate change in general, while allergic subjects in both groups feel significantly more affected (p = 0.04). The severity of symptoms assessed by CAT correlates with the degree of feeling affected (p<0.01). The main disturbing consequences for patients are decreased air quality, increasing numbers of ticks and mosquitos and a rising risk for allergy and extreme weather events such as thunderstroms, while tourists are less disturbed by these factors. Increasing number of heat-days is of little concern to both groups. CONCLUSION: Overall patients are more sensitive to health-related consequences of climate change. Yet, the hazard of heat-days seems underestimated and awareness should be raised.

Comparison of Transcutaneous and Capillary Measurement of PCO2 in Hypercapnic Subjects.

BACKGROUND: Measurement of PCO2 is vital in determining effective alveolar ventilation. However, obtaining capillary PCO2 by a skin prick of the earlobe is painful, and nocturnal measurements disturb sleep. End-expiratory measurement of PCO2 is also well established, but there is a low precision in predicting arterial or capillary CO2. The purpose of the study was to evaluate nocturnal measurement of noninvasive, transcutaneous PCO2 (PtcCO2 ) measurement in hypercapnic subjects. METHODS: In this prospective study, 31 subjects with chronic hypercapnic failure--in a stable phase of the underlying disease--and a control group of 12 healthy volunteers were included. Transcutaneous measurements were taken by the Tosca sensor (Radiometer, Copenhagen, Denmark) over a period of at least 6 h during the night. A capillary blood gas was measured at midnight and 4:00 am. RESULTS: The mean nocturnal capillary PCO2 (PcapCO2 ) of subjects was 50.6 ± 10.2 mm Hg. In the 31 subjects with known hypercapnic respiratory failure, the correlation between PtcCO2 and PcapCO2 at midnight was 0.86 and at 4:00 am r = 0.80. The bias of the hypercapnic subjects was d = + 4.5 with a limit(s) of agreement of 2 SD = 13.0. The process of blood sampling caused no significant change in PtcCO2 . CONCLUSIONS: Our study evaluated transcutaneous capnography as a continuous nocturnal measurement in hypercapnic subjects. We found a good agreement between the methods. Because CO2 is not constant in patients with respiratory failure, but instead fluctuates, we would recommend the continuous transcutaneous measurement of PCO2 as our method of choice in the diagnosis of nocturnal hypercapnia.

The role of transbronchial cryobiopsy and surgical lung biopsy in the diagnostic algorithm of interstitial lung disease.

BACKGROUND AND AIMS: It is not yet known if transbronchial cryobiopsy (TCB) is a reliable and safe diagnostic tool in the investigation of interstitial lung disease (ILD). To date, there have been no studies directly comparing the value of TCB with that of surgical lung biopsy (SLB). The study was initiated to determine whether the samples taken by TCB lead to a reliable diagnosis and whether SLB can be avoided in a relevant percentage of cases. METHODS: We analyzed 32 subjects with suspected ILD who underwent a TCB. Subjects' baseline characteristics, pathological findings after TCB and SLB, and complication rates were analyzed. The pathological inter-rater agreement was quantified statistically. RESULTS: The overall inter-rater agreement concerning TCB sample evaluation was good with a kappa value of 0.80. In 23/32 cases (72%), the findings from the TCB showed a strong congruence with all other clinical data, thereby enabling a definitive diagnosis. Eight of the remaining nine subjects gave their consent for an SLB, which led to a definitive histological diagnosis in six cases (75%). Following TCB, pneumothorax occurred in 6/32 subjects (19%) and endobronchial bleeding was moderate in 8/32 (25%) and was severe in 17/32 cases (53%). CONCLUSION: This is the first study to correlate histological results and complications following TCB and SLB in ILD subjects, some of whom underwent both procedures. TCB is a suitable diagnostic tool in ILD, potentially completely dispensing with the need for an SLB in some cases. In all cases, an interdisciplinary case evaluation is necessary as a final step.

Successful weaning and decannulation after interventional bronchoscopic recanalization of tracheal stenosis.

PURPOSE: Early posttracheostomy tracheal stenosis (PTTS) may cause weaning and decannulation failure. Although bronchoscopic recanalization offers an effective treatment, it is not known how successfully patients can be weaned and decannulated after recanalization. The aims of this study were to determine the incidence of PTTS in a modern weaning center and to elucidate the benefit of interventional recanalization in terms of weaning and decannulation success. MATERIALS AND METHODS: A total of 722 patients admitted within a 24-month period were examined. Patients' baseline characteristics, incidence of weaning and decannulation failure, incidence of PTTS, and rate of postinterventional weaning and decannulation success were determined. RESULTS: Of 722 patients, 450 were deemed suitable for weaning from invasive ventilation. Two hundred eighty-eight patients showed initial weaning and decannulation failure, and 14 of these 288 patients (4.9%) were found to have a PTTS. Recanalization was performed in all cases without procedure-associated complications. Ten (71%) of 14 patients could be successfully weaned and decannulated. Seven of these 10 patients were discharged, 3 patients died during the hospital stay, and 4 (29%) of 14 patients could not be weaned. CONCLUSIONS: Posttracheostomy tracheal stenosis remains a relevant cause of weaning and decannulation failure. Bronchoscopic recanalization is safe and facilitates weaning and successful decannulation in about half of the cases.