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Die Diagnostik und Therapie schlafbezogener Atmungsstorungen (SBAS) unterliegt wesentlichen Veranderungen sowohl in medizinisch-wissenschaftlicher Hinsicht als auch in Bezug auf die Versorgungssituation der Patienten und soziookonomische Aspekte. Die Relevanz der SBAS fur die Morbiditat und Mortalitat Betroffener ist neben der besseren Differenzierung und Phanotypisierung der Untertypen der SBAS Gegenstand intensiver Forschungsaktivitaten. Diese differenzierte Betrachtung verandert die Vorgehensweise beim Verdacht auf SBAS erheblich. Dem stehen Trends zur Simplifizierung des diagnostischen Prozederes und der Therapieeinleitung, der Verlagerung medizinischer Leistungen auf nicht-medizinisches Personal und Fragen der Kostenminimierung entgegen. In diesem Konsensuspapier werden daher vor dem Hintergrund der aktuellen Situation die Prinzipien der Diagnostik, Therapieeinleitung und Versorgung, sowie die Rolle der verschiedenen Beteiligten am Gesundheitssystem und die Bewertung der Therapieangebote vorgestellt. Zu den Kernstucken gehoren die Differenzierung der Diagnostik in Screening, Bestatigungsdiagnostik und Differenzialdiagnostik, der Zugang zum Patienten nach der Vortestwahrscheinlichkeit und ein therapeutischer Algorithmus.

Hintergrund: Patienten mit obstruktiver Schlafapnoe (OSA) leiden an Tagesschlafrigkeit, kognitiven Storungen und weisen ein erhohtes kardiovaskulares Risiko auf. Zusatzlich zu kontinuierlich positivem Atemwegsdruck (CPAP) kann eine Veranderungen des Lebensstils mit Steigerung der korperlichen Aktivitat zu einer Verbesserung des Risikos beitragen. Die tagliche Trainingsdauer sollte mindestens 20 Minuten betragen, um einen relevanten Effekt zu erzielen. Neben einem Training in Trainingsgruppen ist ein hausliches Training sinnvoll. Jedoch wird ein ausreichend intensives Training aufgrund fehlender Ruckkopplung (Monitoring) haufig nicht durchgefuhrt. Unklar ist bis jetzt, wie viel OSA-Patienten mit einem telemonitorisch uberwachten Fahrrad-Heimtraining einverstanden sind und in welchem Mase sie die fur zu Hause vorgegebenen Trainingszeiten einhalten. Methodik: Von 152 konsekutiv befragten OSA-Patienten stimmten 74 (48,7 %) einem 4-wochigen Fahrradheimtraining zu. Nach Ausschluss von 51 Patienten, 17 aus logistischen Grunden und 34 wegen gravierender Komorbiditaten, verblieben 23 Patienten (Alter 51,0 +/− 9,3 Jahre, BMI 33,7 +/− 4,2, ESS-Score 10,4 +/− 6,7, AHI 33,8 +/− 24,0). Die tagliche Zeitdauer des Trainings im Bereich der ventilatorischen Schwelle (VT1) wurde mittels eines Funkmodems (Cinterion) registriert und uber Internet zum Arzt oder Trainingsleiter ubertragen. Ergebnisse: Die Patienten trainierten wahrend 27,3 +/− 2,9 Tagen. Die Mindesttrainingsdauer von > 20 min pro Tag erreichten 19 der 23 Patienten (83 %). Bei 4 Patienten (17 %) lag die Trainingszeit unterhalb dieser Zielmarke mit 5,9 +/− 2,3 min. Die durchschnittliche Trainingszeit aller Patienten lag bei 24,4 +/− 9,0 min. Schlussfolgerungen: Etwa die Halfte der Patienten mit OSA ist an einem regelmasigen, korperlichen Fahrrad-Heimtraining mit Telemonitoring interessiert und fuhrt dieses relativ konsequent durch. Die beschriebene Telemonitoring-Methode stellt ein einfaches und im Verhaltnis zu Gruppentraining kostengunstiges Verfahren zur Reduktion des kardiovaskularen Risikos bei OSA dar.

Dieses Dokument der DGP ersetzt die Empfehlungen von 1998. Anhand der aktuellen Datenlage und einer Konsensuskonferenz wurden Empfehlungen zu Indikationen, zur Auswahl und Durchfuhrung der geeigneten Untersuchungstechniken sowie zu den technischen und personellen Voraussetzungen formuliert. Detaillierte Angaben werden zur Blutgasanalyse unter Belastung, zum 6-Minuten-Gehtest und Rechtsherzkatheter mit Belastung sowie zur Spiroergometrie und Stressechokardiografie gemacht. Der richtige Einsatz von Belastungsuntersuchungen bei anstrengungsinduziertem Asthma, bei sportmedizinischen bzw. arbeitsmedizinischen Fragestellungen, bei der praoperativen Risikostratifizierung und beim Therapiemonitoring pneumologischer Erkrankungen wird dargestellt.

Einleitung: In der Epworth-Schlafrigkeits-Skala (ESS) wird nach der Wahrscheinlichkeit des Einschlafens in 8 spezifischen Situationen gefragt. Pathologische Schlafrigkeit (TS) von Patienten mit obstruktiver Schlafapnoe (OSA) wird am haufigsten bei einem ESS-Score ≥ 11 diagnostiziert (TS-ESS). In einer epidemiologischen Studie zur Pravalenz des Schlafapnoe-Syndroms (OSAS) wurden zur Charakterisierung pathologischer Tagesschlafrigkeit (TS-Young) lediglich 3 Fragen mit Ja-Nein-Antworten verwandt: Aufgrund der unterschiedlichen Fragenkonstruktion der ESS und des Young-Fragebogens fragten wir, ob im Vergleich zur ESS eine grosere Anzahl von Patienten mit OSA und TS mit der Kombination beider Fragebogen identifiziert wird. Zusatzlich uberpruften wir die Schlafrigkeitsfragebogen (FB) an mittels objektivem Vigilanztest definierten Gruppen von OSA-Patienten. Methodik: Mittels PSG wurden 328 OSA-Patienten mit einem AHI ≥ 5 identifiziert. Die Vigilanz wurde mit dem Computerprogramm CARDA untersucht. Ergebnisse: Mit beiden FB fand sich mit 48 % derselbe Prozentsatz von Patienten mit AHI > 5 mit pathologischer Schlafrigkeit. Durch Kombination beider FB (TS-Komb) erhohte sich die Anzahl der Patienten von 158 (48,2 %) auf 195 (59,5 %) signifikant. Die Kombination ergab damit eine signifikant hohere Trefferquote mit zusatzlich 37 (11,3%) Patienten im Vergleich zur TS-ESS allein. Kombiniert man bei Patienten mit unterdurchschnittlicher Fehlerzahl (n = 192) im Vigilanztest beide FB, resultiert eine Zunahme von TS von 23,2 % auf 31,4 % dieser Falle p Schlussfolgerungen: Als Einzeltest konnen beide Fragebogen mit gleicher Trefferquote fur Tagesschlafrigkeit verwendet werden. Durch die Kombination beider Fragebogen findet man im Vergleich zur ESS allein besonders bei Patienten ohne Einschrankung der Vigilanz einen hoheren Prozentsatz von Tagesschlafrigkeit.

Biological signals recorded by polysomnography such as electroencephalograms (EEG), electrooculograms (EOG) und electromyograms (EMG), airflow, thoracic and abdominal motions, O 2 saturation and heart frequency pass through a processing chain with amplification and filtering of the measured variables. In the signal processing the original signal is manipulated to extract information in order to correlate various parameters and to visualise the signal in different representations. The task of the clinician is now to take advantage of the information available and to come to clinical conclusions. Therefore the characteristics, especially the methodology of the signal processing in the devices, should be disclosed by the manufacturers and thus be verifiable. In this review for the example of O 2 saturation, the consequence of different processing criteria with regard to the apnea/hypopnea index is presented. Biosignals such as the respiratory flow are also increasingly being used to control therapy equipment for automatic CPAP devices (APAP). However, the implemented algorithms are often not known, and cannot directly be derived from the polysomnographic records under APAP therapy. In model experiments with a flow generator, defined flow patterns can be simulated. Using bench tests with simulated apneas and waking periods, diagnosed from the flow characteristics, the methods of signal processing can be verified by measuring the pressure profiles and made more transparent for the clinician.

Background: Decannulation failure is usually due to tracheal obstruction. Prior to decannulation, inspection by the invasive procedure of bronchoscopy that permits morphological evaluation of a tracheal stenosis is standard practice. A non-invasive method enabling the quantification of the airway obstruction that requires little cooperation is measurement of the airway resistance by the forced oscillation technique. Objectives: The aim of the present study was to define oscillatory impedance thresholds which predict successful decannulation. Methods: A total of 131 patients were investigated prospectively. Step 1: Following probatory decannulation, measurement of the oscillatory impedance. Step 2: Blinded to the results of the impedance measurement, bronchoscopy-assisted decannulation attempt. The criteria for renewed cannulation were high-grade laryngeal or tracheal obstruction, dyspnea or stridor, or a drop in SaO2 2 insufflation. Statistics: Determination of the ratio tracheal tube remains/tracheal tube removed (TT+/TT–) for every measured value of the oscillatory resistance at 5 Hz (Ros 5 Hz). Determination of specificity and positive predictive value for determined threshold values with respect to TT–. Results: The data of 126 patients were evaluated. TT+ n = 26, TT– n = 100. Decannulation on the basis of bronchoscopy criteria: Specificity and positive predictive value found out for Ros 5 Hz Conclusions: Measurement of the oscillatory airway resistance represents a practicable method prior to decannulation. Below a value of Ros 5 Hz

Background Patients with obstructive sleep apnoea syndrome (OSAS) under continuous positive pressure (CPAP) often complain about drying-up of the throat and nasal mucosa. In many cases the problem can be eliminated with a heated humidifier (WLB). Especially in a cold environment condensation forming on cooling of the air in the tube and the mask can be observed. To avoid this, some patients use an insulating tube covering. We investigated the effect of temperature (T) and relative humidity (rH) of the environment, the ventilation pressure, mask leaks, insulation of tubing on the T and rH% of the delivered air at the end of the tube or in the mask in OSAS patients. Method All measurements were performed with a conventional WLB (S8, Resmed Fa) and a temperature and humidity sensor (Fa Testo, Lenzkirch). Patients 8 patients with OSAS were examined during the day at a room temperature of 16.4 degrees C. Results The temperature at the outlet of the WLB increased with a higher ambient temperature. Through isolation with a hose cover the temperature drop in the tube was reduced by 2.3 degrees C. By tube insulation a mean increase in temperature between 1.6 and 1.0 C during normal breathing in dependence on the leakage flow in the mask was found. Conclusions Due to additional insulation with a tube cover the mask temperature can be increased, albeit slightly, and the formation of condensation is reduced.

Background: Cryoextraction is a procedure used for the recanalization of obstructed airways caused by visible exophytic endobronchial tumor. Biopsy samples obtained by this technique have been shown to be useful for histological assessment. Objectives: The aim of the present animal study was to systematically evaluate biopsy size, histological quality and bleeding risk after cryobiopsy with new, flexible cryoprobes in comparison with forceps biopsy, serving as the gold standard. Methods: Biopsies were obtained from anesthetized pigs with the flexible bronchoscopy technique, and evaluated histologically with respect to their size and quality. Bleeding frequency, bleeding duration and histological changes in the biopsy bed were also recorded. Results: Cryobiopsies were significantly larger than forceps biopsies. The size of cryobiopsies was dependent on the freezing time. The histological quality of the cryobiopsy specimenswas not impaired by the freezing process, whereas forceps biopsies showed typical crush artifacts. Despite the larger defects left in the tracheobronchial system after cryobiopsy, bleeding frequency and duration were not higher compared to forceps biopsy. Conclusions: Since cryobiopsy sampling is not associated with a higher bleeding risk compared with forceps biopsy, this new biopsy technique offers – in addition to a good specimen quality – a safe and valuable tool with the potential of improving the outcome of diagnostic endoscopy.

Introduction The function of automatic CPAP devices is difficult to investigate using clinical examinations due to the high variability of breathing disorders. With a flow generator, however, identical breathing patterns can be reproduced so that comparative studies on the behaviour of pressure of APAP devices are possible. Because the algorithms of APAP devices based on the experience of users can be modified without much effort, also previously investigated devices should regularly be reviewed with regard to programme changes. Questions Had changes occurred in the algorithms of 3 selected devices--compared to the previously published benchmark studies? Do the current versions of these investigated devices differentiate between open and closed apnoeas? Method With a self-developed respiratory pump, sleep-related breathing patterns and, with the help of a computerised valve, resistances of the upper respiratory tract were simulated. Three different auto-CPAP devices were subjected to a bench test with and without feedback (open/closed loop). Results Open loop: the 3 devices showed marked differences in the rate of pressure rise but did not differ from the earlier published results. From an initial pressure of 4 mbar the pressure increased to 10 mbar after a different number of apnoeas (1-6 repetitive apnoeas). Only one device differentiated between closed and open apnoeas. Closed loop: due to the pressure increase, the flow generator simulated reduced obstruction of the upper airways (apnoeas changed to hypopnoeas, hypopnoeas changed to flattening) but different patterns of pressure regulation could still be observed. Conclusion By applying bench-testing, the algorithms of auto-CPAP devices can regularly be reviewed to detect changes in the software. The differentiation between open and closed apnoeas should be improved in several APAP devices.

INTRODUCTION Regular moderate physical activity in COPD reduces morbidity and improves life expectancy. Many programmes often fail after rehabilitation because regular training at home, possibly caused by a lack of motivation, is not maintained, the performance parameters then decline to the prerehabilitation levels. For cost reasons, a simple procedure is required to measure the training times in the home environment with a daily transmission of telemetric data so that, in the case of decline, advice and assistance can be provided. QUESTIONS How long is the actual daily training time monitored by telemetry of COPD patients if a target of 20 minutes per day is prescribed by the doctor? Is there a correlation between physical activity at home and the training period? METHOD We used a device for training the upper extremities with a GSM data transmission module for the transfer of the training times. The physical activity before an exacerbation of COPD and the willingness to modify the training behaviour were determined by questionnaires. 13 patients with COPD (age 69 +/- 9 years, FEV1 48.6 +/- 23.9 %) were investigated prospectively for 6 days under stationary conditions. RESULTS The mean training period (target 20 min/day) was 16.1 +/- 11.7 min/day. The frequency of physical activity per week correlated with the daily ergometry training period in the clinic (r = 0.59). CONCLUSION Training supervised by telemonitoring represents a useful way to objectively obtain training times. Ergometric training in combination with online transmission (telemetric monitoring) and regular phone calls could be an inexpensive method to increase physical activity.

Sarcoidosis is a multisystem disease of unknown origin characterised by epitheloid cell granulomas in the lung and many other organs. The measurement of the alveolo-arterial O(2)-gradient (AaDO(2)) during exercise is the most sensitive method to detect the involvement of the lung with impairment of gas exchange. The method is suitable for follow-up observations to make the indication for a steroid therapy in the case of deterioration. In this case presentation using the 9-panel display proposed by Wasserman we diagnosed besides a slight impairment of the gas exchange a cardiocirculatory dysfunction with a reduction of the oxygen pulse and a reduced minute ventilation with a decrease of the alveolar ventilation. The hypoventilation could be explained by a weakness of the respiratory muscles or a reduction of the central respiratory drive. The functional disturbances could be diagnosed by spiroergometry without expensive or invasive methods. The findings should be examined more specifically with regard to therapeutic consequences.

Patients often report of dyspnea during exertion which should be further analysed as a hint of heart or lung disease. When case history, chest X-ray, ECG, spirometry, and methacholine test do not explain the complaints, a cardiopulmonary exercise test is recommended. Parameters of spiroergometry can often elucidate cardiocirculatory or pulmonary causes. In cardiocirculatory triggered dyspnea the following pattern can be found: reduced maximal oxygen consumption and work rate (WR), an early plateau of oxygen consumption/WR, reduced increase of oxygen consumption/WR, reduced heart rate reserve < 15 beats/min, reduced oxygen pulse and an early plateau, increased breathing reserve, an increased minute ventilation/CO (2) production indicating increased dead space ventilation. In pulmonary triggered dyspnea the following pattern can be found: reduced maximal oxygen consumption, increased heart rate reserve, reduced breathing reserve. With the exercise tidal flow volume loop plotted within the maximal flow volume loop a more thorough interpretation is possible. In a case presentation, the decision-making process using the 9-panel display of Wasserman is demonstrated.

STUDY OBJECTIVES To investigate the efficacy of tongue-muscle training by electrical neurostimulation of the upper-airway muscles as an alternative therapy option for obstructive sleep apnea syndrome. DESIGN A randomized, placebo-controlled, double-blind study. SETTING Department of pneumology and sleep laboratory, University of Witten/Herdecke, Germany. PATIENTS 67 patients with an apnea-hypopnea index of 10 to 40 per hour were randomly assigned to 2 groups: a treatment group of 33 patients (mean age, 50.8 +/- 12.1 years; mean body mass index, 29.1 +/- 4.4 kg/m2) and a placebo group of 34 patients (mean age, 53.3 +/- 11.3 years; mean body mass index, 28.9 +/- 4.9 kg/m2). Fifty-seven patients completed the study. INTERVENTIONS Tongue-muscle training during the daytime for 20 minutes twice a day for 8 weeks. MEASUREMENTS AND RESULTS Treatment efficacy was examined by polysomnography. Snoring, but not apnea-hypopnea index, improved with stimulation (snoring baseline, 63.9 +/- 23.1 epochs per hour; stimulation training, 47.5 +/- 31.2; P < .05) but not with placebo training (snoring baseline, 62.4 +/- 26.1 epochs per hour; placebo, 62.1 +/- 23.8; NS.). CONCLUSIONS Although tongue-muscle training cannot generally be recommended for the treatment of sleep apnea, the method has proven to be effective in the treatment of snoring.

Patients with obstructive sleep apnea syndrome suffer from reduced continuous attention due to neuropsychological deficits. Among other means, driving simulator programs are employed for registration and objectification as well as observation of the course of therapy. While Steer Clear by Findley et al. and the driving simulator Carda (Randerath et al.) represent pure continuous attention tests, the new driving simulator test Carsim, measures attention interactively and continuously. This way, more complex functions are recorded. We therefore investigated Carda and the program Carsim to study the various features of both methods. For this purpose, 105 OSAS patients were tested on both driving simulators concerning the mistake rate in Carda and the time of tracking deviations in Carsim. We defined the normal range by using the mean value +/- 2 standard deviations from our earlier publications in healthy persons without sleep disorders. With Carda the mistake rate exceeded in 10 of 105 patients (9.5%) the normal range and with Carsim the frequency of tracking deviations exceeded in 49 of 105 patients (46.7%) the normal range. The incidence of deviation from normal was significantly higher with Carsim testing. By additionally testing the number of pathological cases is with Carda increased from 46.7% to 51.4%. The tests characterize different components of neuropsychological deficits. Driving simulators with tracking tasks describe neuropsychological deficits in comparison with those measuring only components of reaction in a higher percentage. Language: de

BACKGROUND Exercise training is recommended for patients with severe chronic obstructive pulmonary disease (COPD) to improve the endurance capacity. While many patients confined to bed are not able to run exercise training, we investigated the influence of a bedside passive-ergometry on ventilation in patients with severe COPD. METHODS In nine patients with severe COPD confined to bed (FEV1.0 0,94 +/- 0,18 l, IVC 2,3 +/- 0,8 l, Raw 0,91 +/- 0,13 kPa/l/s) we measured oxygen uptake O2, breathing frequency BF and minute ventilation E during rest, passive movement (30 revolutions per minute), additional active movement and maximal exercise. As a control group six healthy men were investigated during rest and passive movement. RESULTS During maximal exercise in COPD patients O2 peak reached 618 +/- 177 ml/min, BF 26 +/- 7,2/min and E max 24,1 +/- 5 l/min. In rest O2 was 311 +/- 56 ml/min (53 % O2 peak), BF 17,6 +/- 3,1/min and E 13,3 +/- 2,7 ml/min (55 % E max), while during passive movement O2 was increased to 369 +/- 88 (62 % O2 peak), BF to 19 +/- 5,3 and E to 16,4 +/- 4,1 (68 % E max). In contrast O2 in control subjects dropped from 377,5 +/- 38 in rest to 336 +/- 27 ml/min during passive action, BF from 14 +/- 2,1 to 12 +/- 2,4/min and E from 11,1 +/- 1,3 to 9,1 +/- 1 ml/min. CONCLUSIONS In patients with severe COPD oxygen uptake, breathing frequency and minute ventilation increased not only during active, but even during passive movement of a bedside ergometer. With this method an exercise training is possible even in COPD patients confined to bed.

UNLABELLED Besides the standard method of anterior rhinomanometry (aR), the impulse-oscillometric rhinometry (IOS) is available for measurements of the nasal resistance. The aR is a procedure dependent on the cooperation of the patient, whereas IOS is measured regardless from the breathing activities of the patient. We examined weather the resistance-measurement by means of IOS in comparison to the aR is a more suitable method for nasal allergic provocation. METHOD 17 patients with anamnestic known rhinokonjunktivitis (6 f, 11 m) had a pricktest and then a nasal provocation testing with an allergen which provoked a reaction on the skin. The complete resistance of the nose was measured in a randomized order by means of aR and IOS. RESULTS The complete resistance showed neither in the basic measurement (aR 0,38 +/- 0,14 kPa/l/s; IOS 0,38 +/- 0,11 kPa/l/s) nor in the control solution (aR 0,38 +/- 0,14; IOS 0,39 +/- 0,14) nor after application of the allergenic solution (15 min: aR 0,69 +/- 0,27; IOS 0,77 +/- 0,42; 30 min: aR 0,65 +/- 0,29; IOS 0,6 +/- 0,38) a significant difference between the two methods. The results of the measurement of aR and IOS after the allergenic solution showed a positive correlation (15 min: r = 0,63, p < 0,01; 30 min: r = 0,67, p < 0,01). We found by means of clinic and measurement methods in the aR of 7 patients a positive reaction, within 7 patient a negative reaction, 3 patients had a unspecific nasal hyperreactivity. There was a correspondence in 6 of the 7 patients with positive reaction in aR between both methods. 4 of the 7 results with negative reaction in the aR would have been positive then underlying the same criteria in the IOS without announcing the symptomscore a relevant clinical symptomatic while testing. CONCLUSION IOS is a suitable procedure for nasal provocation testing and provides results similar to the aR. In comparison to aR IOS is not dependent on the patients cooperation. Due to its higher sensitivity the valid limits of the aR at provocation testings cannot be transferred to IOS to avoid a false positive reaction.

Constant continuous positive airway pressure (CPAP) is the treatment of choice for the obstructive sleep apnea syndrome (OSAS). To enable the pressure to be matched more accurately to actual requirements, and thus increase patient acceptance, an autoadjusting device based on the measurement of upper airway impedance was developed (APAP(FOT)). We investigated the efficacy and compliance in continuous use at home. Fifty-two patients were treated (randomized crossover) with CPAP and APAP(FOT) for 6 wk each. Respiratory disturbances, sleep profile, and arousals improved significantly with both modes (AHI: baseline, 35.1 +/- 26/h; APAP(FOT), 5.0 +/- 5.2; CPAP, 4.3 +/- 6.3; p < 0.001 baseline versus each mode). The mean pressure with APAP(FOT) was significantly reduced as compared with CPAP (CPAP, 7.8 +/- 1.5 cm H2O; APAP(FOT), 5.7 +/- 1.8 cm H2O; p < 0.001). Under APAP(FOT) the pressure was lower than that under CPAP for 81.5 +/- 21% of the time. Although overall use did not differ, 75% of the patients preferred APAP(FOT) for home treatment. We conclude that APAP(FOT) is as efficacious as constant CPAP in the treatment of OSAS. The treatment pressure can be reduced significantly, and sleep microstructure improved with APAP(FOT). These might be the reasons for patient preference of automatic therapy.

Among other factors, obstructive sleep apnoea (OSAS) patients suffer from impaired continuous attention. For registration and objectification as well as observation of the course of therapy, driving simulation programmes are particularly suitable. "Carsim", a driving simulation newly developed by us, simulates a bendy road via a screen where a vehicle is supposed to be kept on the right lane by operating a steering wheel. Apart from examination of quality criteria (objectivity, reliability, validity) and establishment of standard values, the influence of significant variables (age, gender, school education, profession, duration of disorder, AHI, BMI, visual and motor functionability, driving license, driving experience, Epworth score, accident frequency) on patients and healthy controls requires to be evaluated. For this purpose, 100 healthy controls, 200 OSAS patients and 30 patients under nCPAP were analysed. In healthy persons and patients under nCPAP, driving experience had no impact on the driving simulation results. OSAS patients with no driving license and no driving experience achieved lower marks for tracking than patients with driving license or a lot of driving experience (no driving license: x = 8058 +/- 10,878 track deviations; with driving licence: x = 2111 +/- 6564 track deviations; p Language: de

The measurement of oronasal flow during sleep studies using thermistors is internationally well accepted. As an alternative the possibility exists to measure the pressure at the nose by means of nasal prongs. Our objective was to compare and evaluate the methods to detect respiratory events in clinical routine, namely O2-saturation by pulse oxymetry oronasal flow by thermistors thoraco-abdominal effort by belts oronasal flow by prongs, 8 consecutive patients suspected of sleep apnoea syndrome (7 m, 1 f), mean age 56.5 +/- 9.5 years, height 173 +/- 6.4 cm, BMI 28.7 +/- 2.6 kg/m2, Epworth sleepiness scale score 9.1 +/- 3.2, AHI 24.9 +/- 13.7 h-1, lowest SaO2 86 +/- 4.9%, were examined. Between nose and mouth we fixed an oronasal 3-point thermistor and oronasal prongs (2 openings at the mouth and 2 openings at the mouth applying a common tube). During breathing the resulting pressure was registered with a pressure transducer parallel to the signal of the thermistors and the other polysomnographic data. We defined a respiratory event if at least one of the 4 signals met the criteria of a respiratory disturbance (for exact definitions see method). The detection rate of the 4 signals was calculated in relation to the sum of all events. Of the 1824 events (100%) only 52.3% were detected by an O2-desaturation of more than 4%, but 61.0% by thermistors. An acceptable detection rate was found measuring effort with 83.4%, only nasal prongs detected 95.1% of all events. We conclude that with regard to the detection rate of respiratory events the measurement of pressure by nasal prongs is superior to the use of thermistors.

Cold passover and heated humidifiers are employed for the prevention of side-effects associated with continuous positive airway pressure (CPAP) treatment. However, to date, it has not been possible to separately measure the humidity of inspired and expired air. The aim of this study was to compare the relative humidity of the inspired air and the water loss during respiration between cold passover and heated humidifiers under CPAP. Humidity and temperature were determined separately for the respiratory phases, without humidification, with cold passover and heated humidifiers in 10 healthy subjects. Humidity was measured with a capacitive hygrometer, temperature with a "Type K" thermosensor, and impedance of the total respiratory system with impulse oscillometry. The relative humidity (rH) of the inspired air (mean+/-SD) increased significantly from 24.0+/-9.1%, rH (34.8+/-1.0 degrees C, no humidifier) to 34.5+/-10.1%, rH (34.6+/-1.0 degrees C) under cold humidification, and to 53.9+/-13.2% rH (35.0+/-1.1 degrees C) under heated humidification. With heated humidification, water loss was reduced by 38% compared to cold humidification. The impedance increased from 5.7+/-1.8 cmH2O x L x s(-1) (no humidifier) to 6.7+/-1.8 cmH2O x L x s(-1) (heated humidifier). The authors conclude that the use of a heated humidifier during continuous positive airway pressure appreciably increases the relative humidity of the inspired air and reduces the water loss during respiration.

The bronchopulmonary effects of celiprolol were studied in 12 male asthmatic patients who showed mean maximum changes of -24% in forced one-second expiratory volume (FEV1) and 130% in airways resistance (Raw) following a single, 80 mg dose of propranolol. Celiprolol 200 and 400 mg and placebo were administered in double-blind, random fashion. Raw and FEV1 were determined by whole body plethysmography 1, 2, and 3 h post dose. For placebo and celiprolol 200 and 400 mg, mean maximum changes in FEV1 were 0.6, 2.8, and 2.4%, and for Raw, 11.3, -0.2, and -10.9%, respectively. Pulmonary effects of the three treatments were indistinguishable but differed significantly from propranolol. Five 0.5 mg doses of terbutaline aerosol, administered at 15-min intervals starting 3 h post drug or placebo, caused less bronchodilation after propranolol than after placebo, or celiprolol 200 or 400 mg; the responses after the latter three were indistinguishable. These results suggest that celiprolol is highly bronchosparing and does not block bronchodilation following the beta 2-agonist terbutaline in propranolol-sensitive asthmatics. In contrast to classical beta-adrenoceptor antagonists, celiprolol may afford a greater margin of safety in asthmatic patients with angina or hypertension.