[Analysis of Snoring in Patients with Obstructive Sleep Apnea (OSA) by Polysomnography and LEOSound]. / Die Analyse von Schnarchen bei Patienten mit obstruktiver Schlafapnoe (OSA) anhand von Polysomnografie und LEOSound.

INTRODUCTION: Snoring was monitored in patients with obstructive sleep apnea (OSA) using the LEOSound-Monitor and simultaneously polysomnographic (PSG) recording. In obstructive apneas snoring is normally apparent after apnea termination and the beginning of ventilation. We wanted to know how often obstructive apneas are terminated by ventilation in combination with snoring. METHODS AND INTENTION: In 40 patients with OSA (AHI > 15/h) simultaneous polysomnographic recordings were performed amongst long-term respiratory sound monitoring using the LEOSound monitor. Patients' average age was 57 ±â€Š11 years. Average weight was 100 ±â€Š19 kg by a mean body  mass  index (BMI) of 33 ±â€Š7 kg/m2. 12 out of 40 recordings had to be rejected for further analysis because of artifacts. Snoring recorded by polysomnography was compared with snoring monitored by LEOSound. RESULTS: 3778 obstructive apnea episodes were monitored. LEOSound identified snoring in 1921 (51,0 %), polysomnography in 2229 (58,8 %) obstructive apneas. Only in one patient there was a higher difference in snoring episodes between PSG and LEOSound. DISCUSSION: In nearly 60 % of obstructive apnea events we found snoring during apnea-terminating hyperpnoea. LEOSound is a good diagnostic tool to monitor snoring. It is necessary to clarify why only 60 % of all obstructive events/hyperpnoea develop snoring. From a pathophysiological point of view opening of collapsed upper airway should lead in a very high percentage to turbulences in airstream and committed snoring.

[The Nocturnal Respiratory Rate in COPD Patients of Varying GOLD Severity with/without Nicotine Consumption: Calculation by Means of Breath Sound Analysis]. / Die nächtliche Atemfrequenz bei COPD-Patienten unterschiedlicher GOLD-Schweregrade mit/ohne Nikotinkonsum: Berechnet mittels Atemgeräuschanalyse.

Respiratory rate is an important risk marker and enables early detection of critically ill and vulnerable patients in clinical routine. The aim of this pilot study with 31 patients (COPD severity levels II - IV) was to determine the mean nocturnal respiratory rate based on breath sound recordings and to investigate the dependence of respiratory rate on COPD severity level and smoker status. The mean respiratory rate of the total collective was 19/min. For the COPD-GOLD severity levels, no significant differences in mean respiratory rate could be observed. When nicotine consumption is taken into account, active smokers showed a significantly higher mean respiratory rate of 20.84 ±â€Š4.45/min compared to non-smokers with 17.41 ±â€Š3.14/min (p < 0.05). In addition, active smokers in the study were significantly more frequent among patients with night-time wheezing (60 % vs. 23.8 %). This might suggest that smokers need to perform increased breathing work with increased breathing rate to compensate for oxygen deficiency in bronchial obstruction. The results of the present study show that with the acoustic recording of breath sounds, a reliable representation and calculation of the breath frequency is possible.

[The Pathogenesis of Pulmonary Emphysema - Laennec was right!] / Die Pathophysiologie des Lungenemphysems ­ Laënnec (1781­1826) hatte Recht!

Pulmonary emphysema is characterised by irreversible destruction and enlargement of alveolar structure distal to terminal bronchioles. Small conducting airways < 2 mm in diameter are the major site of chronic airway inflammation and obstruction in COPD patients. 80 - 90 % of the last generation of small conducting airways, the terminal bronchioles, are destroyed in patients with very severe COPD. Recent data showing, that small airways disease is also a pathological feature in patients with COPD GOLD stage 1 and 2. Although 40 % of terminal and 60 % of transitional bronchioles were destroyed, there was no sign for emphysema. Only a significant loss of terminal and respiratory bronchioles seems to be able to induce pulmonary emphysema and respiratory symptoms.

[Are Small Airways the Key to Understanding Pathophysiology and Treatment Efficacy in Chronic Obstructive Pulmonary Diseases?] / Sind die "kleinen Atemwege" der Schlüssel zum Verständnis von Pathophysiologie und Therapieeffizienz chronisch obstruktiver Atemwegserkrankungen?

This review presents updated information on small airways in the pathogenesis of chronic obstructive respiratory diseases. The lungs have a branching structure, segmentally divided from trachea down to the alveoli (generations 1 - 23). Airways can be divided into a conducting (generations 1 - 16) and a respiratory zone (generations 17 - 23). Conducting zone is mainly for air transportation, respiratory zone for gas exchange. Increasing attention has been directed to the role of small airways in chronic obstructive respiratory diseases. The small conducting airways < 2 mm in diameter are the major site of airway inflammation and obstruction in COPD. It has been shown that the last generation of small conducting airways, the terminal bronchioles, are significantly destroyed in patients with very severe COPD. At what stage in the development of COPD the loss of small airways occurs is not exactly known. The small airways represent the most important target for deposition of inhaled therapeutic particles. Currently there is no gold standard for detecting small airway dysfunction. Techniques such as spirometry and body plethysmography can provide information on air trapping. High-resolution CT enables the diagnosis of pulmonary emphysema and diseases of the large airways. Only micro-CT imaging offers the option to describe microstructure of terminal bronchioles. Impulse oscillometry, gas washout techniques and analysis of exhaled nitric oxide are diagnostic tools which have to be validated for diagnosis and treatment response of small airway diseases.

[Asthma Control in Adults and Children Must be Improved!] / Die Asthmakontrolle bei Erwachsenen und Kindern muss optimiert werden!

Medication management of asthma is based on level of asthma control. GINA defined criteria for asthma control include asking about daytime symptoms, limitation of activity, nocturnal symptoms/awakenings and need for reliever treatment. Effective asthma control is necessary for preventing exacerbations and worsening of lung function. Standardized and validated questionnaires such as asthma control test (ACT) help to assess the level of asthma control. Asthma control is classified as controlled, partially controlled or uncontrolled. Multicenter studies like REALISE and AIRE give health care professionals information about effectiveness and adherence to medication over nearly 15 years. Asthma is still poorly controlled in more than 50 % of patients despite the availability of very effective drugs. Low adherence to the treatment, fear of systemic side effects related to long term treatment with inhaled corticosteroids, inadequate knowledge of the disease may be responsible factors for bad asthma control. Optimized tools for disease management and intensified education are necessary for therapeutic success.

[Chronic hypoxia and cardiovascular risk : Clinical significance of different forms of hypoxia]. / Chronische Hypoxie und kardiovaskuläres Risiko : Klinische Bedeutung verschiedener Hypoxieformen.

It is of fundamental importance to differentiate whether chronic hypoxia occurs intermittently or persistently. While chronic intermittent hypoxia (CIH) is found typically in patients with obstructive sleep apnea (OAS), chronic persistent hypoxia (CPH) is typically diagnosed in patients with chronic lung disease. Cardiovascular risk is markedly increased in patients with CIH compared to patients with CPH. The frequent change between oxygen desaturation and reoxygenation in patients with CIH is associated with increased hypoxic stress, increased systemic inflammation, and enhanced adrenergic activation followed by endothelial dysfunction and increased arteriosclerosis. The pathophysiologic consequences of CPH are less well understood. The relationship between CPH and the development of pulmonary hypertension, pulmonary heart disease as well as polycythemia has been established.

[Apnea Detection by Means of Respiratory Sound Recordings and Polysomnography - A Comparative Study]. / Ein Vergleich der Apnoeerkennung bei Patienten mit obstruktiver Schlafapnoe (OSA) anhand von Atemgeräuschaufzeichnungen und Polysomnografie.

Introduction In this study, recognition of apnoeas by means of polysomnography (PSG) and nocturnal respiratory sound recordings in patients with obstructive sleep apnoea (OSA) was analyzed and compared. Methods In 45 patients with OSA requiring treatment (AHI > 15/h), concomitant polysomnographic recordings and long term respiratory sound recordings by means of LEOSound were performed. Patients' average age was 58 ±â€Š12 years (mean ± standard deviation), average BMI was 33 ±â€Š7 kg/m2. Audio-visual apnoea detection by LEOSound was compared to polysomnographic apnoea detection. Increased artifact rate due to dislocation of microphones led to rejection of 11 out of 45 recordings for detailed analysis. Results Comparison of apnea detection by audio-visual analysis and polysomnography yielded a median of 164 apneas for LEOSound recordings and 158 apneas for PSG. Median apnoea index (AI) was calculated to be 20/h for respiratory sounds recording and 21/h for PSG. The correlation of apnea indices from acoustic long term registration and PSG was 0.939 (p < 0.001). Discussion Acoustic long term registration of primary and secondary respiratory sounds is also capable to recognize apnoeas. Exact differentiation between apnoeas and hypopnoeas is only possible in a limited fashion.

[Normal and Adventitious Breath Sounds]. / Atemgeräusche und Atem-Nebengeräusche.

Auscultation of the lung is an inexpensive, noninvasive and easy-to-perform tool. It is an important part of the physical examination and is help ful to distinguish physiological respiratory sounds from pathophysiological events. Computerized lung sound analysis is a powerful tool for optimizing and quantifying electronic auscultation based on the specific lung sound spectral characteristics. The automatic analysis of respiratory sounds assumes that physiological and pathological sounds are reliably analyzed based on special algorithms. The development of automated long-term lungsound monitors enables objective assessment of different respiratory symptoms.

[What is Important for Diagnosis and Therapy Follow-up in Chronic Cough?]. / Was ist für die Diagnostik und Therapieverlaufskontrolle von chronischem Husten wichtig?

Within the last years there has been significant progress in the field of chronic cough. So far, the analysis and evaluation of chronic cough was done mainly on the basis of subjective methods such as manual counts of cough events, questionnaires and diaries. Testing cough hypersensitivity and monitoring 24 h cough represent objective criteria. Validated questionnaires on cough frequency and quality of life represent the impact of chronic cough. Cough frequency monitoring, the preferred tool to objectively assess cough, should be used as primary end-point in clinical trials. It will also be possible to discriminate between productive and non-productive cough. The relationship with subjective measures of cough is weak. In the future, cough and its therapy should therefore be assessed with a combination of subjective and objective tools.

[Determination of Hypercapnic Ventilatory Response in COPD Patients]. / Bestimmung der hyperkapnischen Atemantwort bei Patienten mit COPD.

Previous studies showed a reduced hypercapnic ventilatory response (HCVR) in patients with COPD. However, the association between HCVR and COPD GOLD stages is unknown. The measurement of the HCVR is a methodological option to test the function of the breathing feedback cycle. The aim of this feasibility study was to present a new automatic and standardized device (MATAM) to measure and interpret the HCVR. This device determines if exposure to CO2 leads to an adequate increase in breathing frequency and tidal volume. Recordings are performed in a closed system that allows selective changes of each gas component. The minute ventilation (AMV) under hypercapnic stimulation is plotted against the end-tidal CO2 (ETCO2). The HCVR is defined as the linear regression line.28 patients (18 male; 10 female) with COPD GOLD stages 0 to IV were studied. The patients had a mean age of 57 ±â€Š14 (standard deviation) years and a mean BMI of 32 ±â€Š9 kg/m(2). We could show that the HCVR measurement in patients with COPD using MATAM was feasible. Patients with more severe COPD stages had a significantly more reduced HCVR. This could be an indication of reduced chemosensitivity due to a worsening of blood values (pH and pCO2) which affect the central chemoreceptors in the long term. Further studies will be needed to validate the MATAM device for healthy individuals and other patient groups, and for the investigation of standard values.

[Pilot Project: Improved Lung Deposition via a New Nasal Inhalation Procedure]. / Pilotprojekt zur verbesserten Lungendeposition durch ein neues Verfahren der nasalen Inhalation.

INTRODUCTION: Inhaled drugs can only be effective if they reach the middle and small airways. This study introduces a system that combines a trans-nasal application of aerosols with noninvasive pressure support ventilation. METHODS: In a pilot study, 7 COPD patients with GOLD stages II and III inhaled a radiolabeled marker dissolved in water via a trans-nasal route. The mean aerosol particle size was 5.5 µm. Each patient took part in two inhalation sessions that included two application methods and were at least 70 hours apart. During the first session ("passive method"), the patient inhaled the aerosol through an open tube system. The second session ("active method") included pressure support ventilation during the inhalation process. A gamma camera and planar scintigraphy was used to determine the distribution of aerosol particles in the patient's body and lung. RESULTS: The pressure supported inhalation ("active method") results in an increased aerosol lung deposition compared to the passive method. Above all, we could demonstrate deposition in the lung periphery with relatively large aerosol particles (5.5 µm). DISCUSSION: The results prove that the combination of trans-nasal inhalation with noninvasive pressure support ventilation leads to significantly increased particle deposition in the lung.

[Cheyne-Stokes respiration in patients with chronic heart failure: only a diagnostic marker or also a cardiovascular risk factor?]. / Cheyne-Stokes-Atmung bei Patienten mit chronischer Herzinsuffizienz: nur diagnostischer "Marker" oder auch kardialer Risikofaktor?

Sleep disordered breathing with predominant obstructive or central apnea is an under-recognized but highly prevalent comorbidity in patients with chronic heart failure. As the severity of heart failure increases the prevalence of central sleep apnea (CSA) and Cheyne-Stokes respiration (CSR) is also much more frequent. Cheyne-Stokes respiration is characterized by alternating periods of crescendo and decrescendo respiration followed by central apnea. Present data indicate that CSA-CSR is not only a compensatory response to severe heart failure but also a predictor of worse prognosis. However the results on long-term mortality are not consistent. The prognostic importance of night- and daytime CSR has to be further elucidated. Increased sympathetic nervous activity has been proposed to play a mayor role concerning progression and outcome of chronic heart failure by CSA-CSR.

[Long-term oxygen therapy (LTOT)--what should physicians, homecare-providers and health insurance companies know?]. / Die Langzeit-Sauerstoff-Therapie (LTOT) - Was sollten Arzt, Versorger und Krankenkasse wissen?

Long-term oxygen treatment (LTOT) has been demonstrated to improve prognosis in patients with chronic respiratory insufficiency. In terms of pathogenesis, improved oxygenation, reduction of pulmonary artery pressure as well as reduction of respiratory work are important. Since there are considerable differences between the LTOT systems, individually tailored therapy is needed. In particular, the mobility aspects of the patients must be taken into consideration. It is important to distinguish between stationary/mobile devices with a liquid oxygen system and stationary/mobile devices with oxygen concentrator. Oxygen titration should be performed in relation to rest and activity phases (e. g. 6 minute walk test) as well as in relation to the sleep phase. Employing devices with demand-controlled valves should be critically examined. This can be undertaken only under physician orders and requires continuous monitoring.

[Obstructive sleep apnea in neurological diseases: specially as a risk factor for stroke]. / Obstruktive Schlafapnoe bei neurologischen Erkrankungen: Speziell als Risikofaktor für Schlaganfall.

Neurological diseases are frequently associated with sleep-related breathing disorders. In contrast patients with obstructive sleep apnea (OSA) suffer more often from cerebrovascular and cardiovascular diseases. Epidemiological studies have shown that OSA is common among patients with stroke, arterial hypertension or cardiovascular disease. In particular apnea-associated arterial hypertension, atrial fibrillation, activation of the sympathetic nervous system, recurrent hypoxemia and vascular inflammatory response should be considered as risk factors for the vascular system. Early diagnosis and treatment of sleep-related breathing disorders in neurological diseases are required to reduce the risk of subsequent cerebrovascular and cardiovascular diseases.

[Telemonitoring in patients with COPD and acute exacerbations]. / Die akute Exazerbation der COPD.

A major problem associated with COPD is exacerbation. Symptoms include increased shortness of breathing, coughing, wheezing and sputum production. The frequency and severity of exacerbations are associated with a higher mortality risk. Early recognition and treatment have been shown to reduce severity of exacerbations, consecutive morbidity and hospital admissions. Telemonitoring of (nocturnal) lungsounds, oxygen saturation and frequency of breathing may offer the opportunity to detect symptoms of exacerbations very early. Therefore further research is needed to clarify precisely the role of telemonitoring in patients with COPD and exacerbations.

[ThorAKUSTIK - a computer-based method to determine the oronasal respiratory flow]. / Bestimmung der Atemstromstärke mithilfe des ThorAKUSTIK-Verfahrens bei Mund- und Nasenatmung.

BACKGROUND: Respiratory flow detection with the aim of detecting sleep-related breathing disorders plays a major role in polysomnography. Due to the fact that pneumotachographs are too bulky and not suitable for measurements during sleep, the ThorAKUSTIK system has been developed. By attaching a noise sensor right next to larynx, it determines the respiratory flow in an acoustic way. METHODS: The ThorAKUSTIK system as well as a pneumotachograph were applied simultaneously. The correlation between those two methods has been calculated. PATIENTS: We investigated twenty male subjects. All of them were non-smokers. RESULTS: The ThorAKUSTIK-System showed a highly positive correlation (r = 0.89 to 0.91; p < 0.01) and was able to measure the respiratory flow in a reliable way. CONCLUSIONS: The ThorAKUSTIK-System allows a long-term live monitoring and has the potential to be used in several clinical departments. Larger studies are necessary to verify the application in the clinical routine.