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T Penzel

Publications and source records attributed to T Penzel.

12 recordsLinked to original sources

Ambulatory diagnosis of sleep-related breathing disorders.

Ambulatory diagnosis of sleep-related breathing disorders (SRBD) is necessary due to their high prevalence and to the limited capacities of sleep centers. Categories of SRBD which must be diagnosed and differentiated are defined. Indications for ambulatory diagnosis are given. A selection of systems on the market in Europe are given and described in terms of their parameters. The correct system for diagnosis in a specific patient must be selected according to the specific question. The issue of ambulatory diagnosis of SRBD has gained importance in Germany because beginning in spring 1992 physicians will be reimbursed if they continuously record respiratory signals, heart rate, oxygen saturation and movement in their patients and if they qualify by attending a one-week training course.

Airway Obstruction

[Analysis of long-term blood pressure measurements during sleep].

Fifty patients with sleep-related breathing disorders and arterial hypertension underwent diagnostic polysomnography for two nights; EEG, EOG, EMG, and respiratory signals were recorded in parallel with invasive blood pressure. Computerized evaluation was performed to calculate systolic and diastolic blood pressure values, as well as heart rate beat-to-beat. All signals were stored once per second for further evaluation. These time series were analyzed in respect of underlying periodicities by means of spectral analysis. It was possible to distinguish four different groups of patients according to the compressed spectral arrays. Pronounced peaks of different extents were found that reflected both periodicities of respiration (3-5 s) and periodicities of sleep apnea (30-60 s). A comparison of spectral analysis of blood pressure and heart rate showed that systolic blood pressure is suited best to recognize periodicities related to respiration and apneas.

Adult

Continuous non-invasive blood pressure monitoring in patients with sleep disorders.

Sleep related breathing disorders are of high prevalence and are often associated with essential hypertension. It is therefore necessary to study blood pressure continuously in all patients with sleep related breathing disorders and arterial hypertension as well as in all patients with essential hypertension and suspected sleep apnoea. To investigate the usefulness of a non-invasive continuous volume-clamp method during sleep we used this technique in parallel with 130 sleep recordings and performed a validation study of the Finapres instrument on a subgroup where continuous invasive blood pressure recordings were available. Absolute pressure values of Finapres are valid when the position and the movement of the sensor were carefully observed and only appropriate segments of the recordings were taken for further evaluation. The high beat to beat resolution of the systolic and diastolic pressure is the main advantage of this non-invasive technique because it reflects rapid blood pressure variations as they occur in sleep related breathing disorders. This could be investigated only invasively until now.

Blood Pressure Determination

Blood pressure and sleep apnea: results of long-term nasal continuous positive airway pressure therapy.

Arterial blood pressure patterns in 12 men with sleep apnea and arterial hypertension were studied at baseline and after 6 months' therapy with nasal continuous positive airway pressure (nCPAP). Preexisting antihypertensive medication was discontinued 1 week before baseline measurements. Weight did not change during the study period; body mass index was 29.3 (range, 25.4-38.5) vs. 29.3 (25.0-38.5). During therapy the apnea index decreased from 58 (range 30-73) to 2 (range 0-7) apneic episodes per hour (p less than 0.01). Intra-arterial systolic (BP sys.) and diastolic (BP dias.) blood pressure and heart rate decreased during therapy (p less than 0.001). Mean values +/- 95% confidence intervals were as follows: BP sys., 147.1 (+/- 1.6) mm Hg vs. 126.4 (+/- 1.5) mm Hg; BP dias., 81.6 (+/- 0.8) mm Hg vs. 69.4 (+/- 0.6) mm Hg; heart rate, 68.8 (+/- 0.7) beats/min vs. 65.4 (+/- 0.7) beats/min. Furthermore, the variability of these parameters decreased during therapy: variability BP sys., 53.8 (+/- 1.1) mm Hg vs. 25.6 (+/- 1.1) mm Hg; variability BP dias., 35.6 (+/- 0.7) mm Hg vs. 17.9 (+/- 0.7) mm Hg; variability of heart rate, 28.1 (+/- 0.7) beats/min vs. 14.9 (+/- 0.7) beats/min (p less than 0.001). During treatment we found that blood pressure scores already dropped during the awake phase, with a further decrease during non-REM and REM sleep (p less than 0.001). Our results, which demonstrate the reversibility of high blood pressure upon treatment of sleep apnea, indicate that sleep apnea can be an etiological factor in hypertension. Sleep apnea should therefore be considered in the differential diagnosis of arterial hypertension.

Adult

[Computer analysis of disturbed respiration in patients with sleep apnea].

In patients with sleep related breathing disorders parallel evaluation of respiration, blood gases and the EEG are indispensible. Computerized methods can provide a detailed analysis of the interrelation of these parameters to enlighten the disturbed central regulation of respiration in these patients. These methods also can help to achieve a better differential diagnosis in routine clinical work. A new method is presented here which evaluates the signals of nasal airflow, thoracic and abdominal movements together with oxygen saturation and heart rate in parallel. The new method is validated using a detailed visual analysis. Results prove the usefulness of the new method. To apply the method the relationship between length of apnea and oxygen desaturation is evaluated for different sleep stages separately.

Blood Gas Analysis

[Assessment of the MESAM and Biox 3700 early warning methods for the diagnosis of sleep-related respiratory disorders in young men].

We can use pulse oximetry as a method for diagnosis of the sleep apnoea syndrome, as well as L-EKG, MESAM II and the actigraph. In this study MESAM II and pulse oximetry were combined for finding out discrete sleep-related breathing disorders. The results were compared with polysomnography. 5 (15.1%) of 32 patients had an index of apnoea (AI) greater than 10, whereas 4 (12.1%) patients showed an AI greater than 5. All of the patients with positive signs in MESAM II/pulse oximetry had an AI greater than 5 in polysomnography, whereas non of the patients with negative signs in MESAM II/pulse oximetry had an AI greater than 5 in polysomnography.

Adult

[SIDAS 2010: mobile 10-channel unit for the diagnosis of sleep-related respiratory disorders].

At the moment diagnosis of sleep related breathing disorders (SRBD) is carried out in specialised clinical centres with well-equipped sleep laboratories. Since there are only few of these in Germany, medical care in this field is not sufficient at all even if applied only to high-risk patients. To cope with the large number of patients with severe SRBD we developed a mobile 10-channel unit (SIDAS 2010) designed for diagnosing SRBD even outside the conventional sleep laboratories. In this study we investigated 108 patients who after using the 4-channel recorder presented signs and symptoms suggesting SRBD. After evaluating the tracings in 53 patients a distinct obstructive sleep apnoea (OSA) (AI 10) could be diagnosed; in 55 patients the signs remained indistinguishable. In 2 recordings with SIDAS in 74 patients, a distinct OSA was diagnosed, 34 patients had an AI less than 10; these patients underwent renewed polysomnographic recordings with EEG in addition. The polysomnographic recordings revealed 5 patients with an AI between 5 and 10.3 with primary and secondary alveolar obstructive hypoventilation due to excessive snoring. The comparison of SIDAS recordings with recordings made by polysomnography proved SIDAS to be valuable in respect of diagnosing type of SRBD (obstructive/central) and amount of respiratory events (apneas/hypopnoeas). In this study only 13 patients with SRBD (14.9%) need further diagnostic procedures. We conclude that with SIDAS most of the SRBD can be diagnosed sufficiently even outside conventional sleep laboratories.

Adult

MESAM: a heart rate and snoring recorder for detection of obstructive sleep apnea.

The high prevalence of sleep-related breathing disorders demands the development of ambulatory recording devices that can handle data with a high degree of selectivity and are easy to use and to interpret. A digital device based on the recording of heart rate and breathing sounds was developed. Patients with sleep-related breathing disorders can be preselected before they undergo sleep laboratory investigations. Treatment control can be achieved ambulatory, having an initial recording.

Ambulatory Care

Effects of cilazapril on hypertension, sleep, and apnea.

Epidemiologic studies revealed that up to 10 percent of middle-aged men show more than 10 cessations of breathing of more than 10 seconds' duration. In these patients, increased morbidity and mortality rates have been proved. More than 50 percent of apnea patients exhibit arterial hypertension, and up to 50 percent of hypertensive patients experience sleep apnea. Patients with sleep apnea and essential hypertension need special attention paid to their antihypertensive therapy because the following side effects of drugs have to be avoided: increases of cardiac insufficiency, hyperviscosity of the blood, intensification of the hypersomnia by central sedation, intensification of a pre-existing tendency towards arrhythmias, and deprivation of deep and rapid eye movement sleep. In this study, the effects of angiotensin-converting enzyme inhibitors in patients with sleep apnea and hypertension are examined. An interim evaluation of six patients (aged 50 to 57) yielded the following results: Average Broca index, 124; average blood pressure before therapy, 159/102 mm Hg; average blood pressure after therapy, 132/78; a decrease of the apnea and hypopnea index from x = 31 (range, 12 to 77) to x = 20 (range, two to 54). Therapy did not influence sleep structure: before therapy, an average of 19 percent of sleep episodes were of the rapid eye movement type (range, 11 to 32 percent); after therapy, 23 percent were of this type on average (range, 21 to 25 percent). A final evaluation will be carried out after the second study phase for 12 patients who have been treated in a double-blind scheme with metropolol versus cilazapril.

Adult