[Computer-assisted nCPAP settings in comparison with conventional methods]. / Computergestützte nCPAP-Einstellung im Vergleich zum konventionellen Verfahren.

CPAP with constant pressure is the method of choice to treat obstructive sleep apnoea. To find the optimal pressure, automatic systems were developed, permitting computerised titration of pressure based on respiratory patterns. One important point in the algorithm of titrating pressure is the shape of the inspiratory breath flow-time relation. It can be used to detect early inspiratory obstruction. In the present study the results of automatic CPAP titration were compared with conventional constant CPAP. In 12 patients with obstructive sleep apnoea syndrome two polysomnographies were performed after diagnosis and conventional titration. In a randomised cross-over study the adequate constant CPAP was compared with computerised variation of pressure by Autoset-CPAP. During both methods apnoeas, hypopnoeas and snoring were reduced. In the autoset mode the number of apnoeas and hypopnoeas was 30.14 +/- 17.6/sleeping time, in the constant mode it was 7.9 +/- 11.2/sleeping time (p < 0.01). The number of episodes with snoring in the autoset mode was 18.7 +/- 21.8 and in the constant pressure mode 7.9 +/- 11.2 (p = 0.054). No difference could be detected in respect of sleeping time, sleep efficiency, arousals and sleep stages. We conclude that in patients accepting constant high pressures constant CPAP remains the method of choice. Automated CPAP offers an alternative in the case of pressure intolerance beneath BiLevel-CPAP.

[Comparative study of thoracic and abdominal effort, respiratory oscillatory impedance (ROI) and intrathoracic pressure in sleep apnea syndrome]. / Vergleichende Untersuchung von thorakalem und abdominellem Effort, respiratorischer oszillatorischer Impedanz (ROI) und intrathorakalem Druck beim Schlafapnoesyndrom.

Oesophageal pressure (Pes) and oronasal flow are necessary to describe upper airway obstruction in patients with obstructive sleep apnoea syndrome (OSAS), but Pes interferes with sleep. We developed a device applying an oscillating flow (20 Hz) through a nasal mask. An additional flow (2.6 l/min) is needed to reduce dead space and humidity. 24 patients (age 55.8 +/- 8.3 years, BMI 28.6 +/- 3.9, RDI 38.6 +/- 19.4, Raw 0.27 +/- 0.07 kPa/s/l) underwent polygraphy (oronasal flow, thoracic and abdominal effort, oxygen saturation, microphone, heart rate). Pes and oscillatory impedance (OI) were measured simultaneously. During snoring, hypopnoeas and apnoeas we compared Pes, OI and effort values for the detection of number and period of airway obstruction. The average Pes during habitual snoring was -3.2 +/- 0.8, during hypopnoeas -3.9 +/- 1.1 and during apnoeas -4.4 +/- 1.6 kPa. We found no significant difference in respect of the number and period of obstruction in patients with apnoeas, whereas in patients with incomplete obstruction (hypopnoea) Pes and OI were found to be more sensitive in detecting obstruction than effort (period: 27.0 +/- 9.1 sec (Pes), 29.0 +/- 4.8 sec (OI) vs. 20.0 +/- 6.8 sec (effort); number: 34.0 +/- 9.1 (Pes), 35.0 +/- 8.5 (OI) vs. 23.0 +/- 9.5 (effort). There is a significant correlation between Pes and OI (r = 0.89). OI is shown to be equally sensitive in identifying Upper Airway Resistance Syndrome as compared to Pes. This method is more convenient than conventional measurements such as Pes and it could be an alternative.

[Effect of noninvasive ventilation on pulmonary artery pressure in patients with severe kyphoscoliosis]. / Der Effekt der nichtinvasiven Beatmung auf den pulmonalarteriellen Druck bei Patienten mit schwerer Kyphoskoliose.

BACKGROUND: Many studies have shown, that non invasive ventilation via nasal access can normalize alveolar ventilation for individuals due to kyphoscoliotic deformity. The purpose of this study was to evaluate the effect of nasal IPPV on the pulmonary artery pressures (Pam) and the sleep efficiency of kyphoscoliotic individuals. PATIENTS AND METHODS: Five patients were studied (4 men, 1 woman; age 50.5 +/- 6.9 years): all patients showed hypoxemia and hypercapnia before therapy. We followed the patients about 6 months under NIPPV. We measured PImax, PaO2, PaCO2, Pam before and after 6 months with NIPPV. RESULTS: PImax increased from 4.9 +/- 2.3 kPa to 6.5 +/- 1.3 kPa, PaO2 increased from 46.2 +/- 12.2 mmHg to 56.7 +/- 8.5 mmHg. PaCO2 decreased from 53.0 +/- 3.2 to 45.3 +/- 3.2. Pam decreased from 41.0 +/- 15.1 to 23.2 +/- 10.7 in 6 months of NIPPV. Total sleep time increased from 222 +/- 52 min to 326 +/- 43 min with NIPPV. CONCLUSION: Similar to O2 long-term therapy in patients with COPD. NIPPV delivers in patients with kyphoscoliotic deformity a significant reduction of pulmonary artery pressure and increase of sleep quality.

[Significance of oscillatory impedance in etiological determination of arousal in sleep related respiratory disorders]. / Die Bedeutung der Oszillatorischen Impedanz (OI) zur ursächlichen Klärung von Arousals bei schlafbezogenen Atmungsstörungen.

Conventional registration of cardiorespiratory data may not explain daytime sleepiness in some patients. Polysomnography may detect arousal reactions that can only be explained by additional registration of esophageal pressure. We developed a device (oscillatory impedance [OI]) which applies an oscillating flow via a nasal mask that allows to detect the pathophysiologic findings of upper airway resistance syndrome. 25 patients (age 47.3 +/- 5.6 years, body mass index 26.6 +/- 3.8 kg/m2) underwent conventional polysomnography and additional measurement of OI. In 59% arousal reactions could not be explained by respiratory data whereas OI demonstrated intermittend obstruction of extrathoracic airways. We therefore conclude that patients with daytime sleepiness that cannot be explained by conventional polysomnographic registrations should undergo measurement of OI.

[Effect of automatically titrated CPAP systems on sleep and respiration in sleep apnea syndrome]. / Einfluss automatisch titrierender CPAP-Systeme auf Schlaf und Atmung bei SAS.

UNLABELLED: We compared an automated self setting CPAP-titration with conventional constant CPAP. In 12 patients with obstructive sleep apnea syndrome 2 polysomnographies were performed after introduction of CPAP-therapy. In a randomized cross-over study a constant CPAP during one night and in a second night a computerized variation of pressure was applied by a self-setting CPAP-device (Auto AdjustTM CPAP). During both methods apneas, hypopneas and snoring were reduced. Apnea index was reduced from 32.5 +/- 28.5 at diagnosis to 3.3 +/- 4.7 by Auto Adjust CPAP and to 4.0 +/- 5.3 by constant CPAP. The results of the 2 methods were not significantly different. Total sleep-time, sleep efficiency and sleep stages did not show any significant difference. CONCLUSIONS: In case of pressure-intolerance automated self setting CPAP offers an alternative beneath BiPAP. The significance of this method with regard to BiPAP therapy must further be evaluated.

[The "neuron-specific enolase" tumor marker as a prognostic indicator in small cell bronchial carcinoma]. / Der Tumormarker "neuronspezifische Enolase" als Prognoseindikator beim kleinzelligen Bronchialkarzinom.

To assess the predictive value of the tumour marker NSE in respect of survival time prognosis in patients with small-cell bronchial carcinoma we performed serial measurements of the NSE concentration in 67 patients in whom the small-cell bronchial carcinoma had been newly diagnosed, before and during chemotherapy or radiotherapy. Pretherapeutic NSE determination proved an important predictive parameter with regard to survival time prognosis. In patients with an initial NSE concentration of over 60 ng/ml the survival time was significantly reduced (from 12.1 months to 8.4 months, p < 0.01). The pretherapeutic NSE concentrations are associated with the initial tumour stage. Serial NSE determinations reflect the course of the disease. A drop in NSE concentrations during the early phase of therapy may be important as a secondary prognosis indicator.

Investigations of the frequency of DNA strand breakage and cross-linking and of sister chromatid exchange frequency in the lymphocytes of patients with multiple myeloma undergoing cytostatic therapy with melphalan and prednisone.

An investigation was made of 17 patients with multiple myeloma using the method of alkaline filter elution for the detection of DNA damage and the determination of sister chromatid exchange (SCE) frequency in peripheral lymphocytes during a course of chemotherapy with melphalan and prednisone. We were able to detect elevated SCE frequencies in pretreated patients that approximately doubled during the therapeutic cycle. An appreciable level of DNA cross-linking was detected by alkaline filter elution; DNA cross-linking scarcely increased during a course of chemotherapy. The increase in the SCE frequency during the first therapy cycle was even greater in the case of patients with newly diagnosed multiple myelomas. The results obtained by alkaline filter elution and measuring SCE frequencies suggest that these techniques are suitable as methods in molecular epidemiology, especially if applied to persons who are chronically exposed to cytostatic drugs. Whether or not the methods could be valuable in evaluating therapy response needs further investigation.