Search

It has been hypothesized that sleep apnea syndrome (SAS) increases hypothalamicpituitary-adrenal axis activity and, through increased cortisol levels, participates in the pathophysiology of metabolic and cardiovascular complications. We compared the circadian profiles of cortisol in obese men with [obSAS+; apnea-hypopnea index (AHI) [greater than or equal to] 20/h] and without SAS (obSAS-; AHI [less than or equal to] 5/h). 1) Salivary cortisol (5 samples: before/30 min after dinner, 2100, upon/30 rain after awakening) was measured in 15 obSAS+, 19 obSAS-, and 19 normal-weight controls (NWC). 2) Plasma cortisol (every 30 rain for 24 h under highly controlled conditions and portable EEG device) was measured in 9 obSAS+, 8 obSAS-, and 10 NWC men. Visceral adipose tissue surface was measured by CT scan. In both studies, obSAS+ and obSAS- men were comparable for age, BMI, waist circumference, and waist-to-hip ratio. First, no difference was found, using ANOVA for repeated measures, between obSAS+ and obSAS- subjects for any salivary cortisol measurement. No correlation was found between salivary cortisol and AHI or nocturnal Sa[O.sub.2]. Similarly, obSAS+ and obSAS- men showed no difference in plasma cortisol rhythmicity: 24-h minimum, maximum, and mean, ANOVA for repeated measures, mathematical modeling of cortisol rhythm (COSINOR), and morning secretory peak. Conversely, ANOVA for repeated measures showed decreased cortisol levels in obese vs. NWC men during both the trough (2200-0130) and the peak (0600-0900) independently of SAS status. We show that SAS per se is not associated with any change of the level or of the features of salivary and plasma cortisol rhythmicity and confirm that men with visceral obesity display lower plasma cortisol levels than NWC men. cortisol; circadian rhythm; obesity; sleep-disordered breathing

Twenty patients admitted to hospital with serious lower respiratory tract infections entered an open study of 400 mg enoxacin given orally twice a day for a minimum of seven days. Clinical signs and symptoms were completely cured or improved in six of eight patients with pneumonia, in nine of ten patients with bronchitis, and in two patients with bronchiectasis. Enoxacin was effective in eradicating the initial pathogens in 10 of 12 patients with positive cultures. Enoxacin was well tolerated. Only one treatment-related side-effect was observed during the study. Nine patients received concurrent treatment with theophylline, but no signs of theophylline toxicity were seen. Enoxacin is a safe and effective alternative to parenteral treatment of lower respiratory tract infections. [ABSTRACT FROM PUBLISHER]

Introduction: This French, multicenter, randomized double-blind controlled trial tested the hypothesis that pressure reduction during exhalation (C-Flex; Respironics; Murrysville, PA) would improve continuous positive airway pressure (CPAP) compliance, comfort, and quality of life., Methods: Two hundred eighteen newly diagnosed sleep apnea patients (seven centers; mean [+/- SD] age, 55 +/- 11 years; mean body mass index, 31 +/- 6 kg/m(2); mean apnea-hypopnea index, 44 +/- 21 events/h) were randomly assigned to receive 3 months of treatment with CPAP (108 patients) or C-Flex (110 patients). Objective compliance, generic quality-of-life questionnaire (SF-36) scores, disease-specific quality-of-life questionnaire (Grenoble Sleep Apnea Quality of Life [GrenobleSAQOL]) scores, and visual analog scales for CPAP comfort and side effects were determined at baseline and after 3 months. After 3 months, patients in the CPAP arm were moved to the C-Flex arm for 3 additional months (open study)., Results: An intention-to-treat analysis demonstrated that there were no differences at 3 months between C-Flex and CPAP use in terms of compliance, the rate of side effects, and comfort. Low compliers receiving CPAP therapy (< 4 h of use) significantly improved this outcome during the open study (p = 0.04). There was a significant improvement in six of eight of the SF-36 domain scores and in all of the domains of the GrenobleSAQOL scores in both groups using either CPAP or C-Flex., Conclusion: In unselected sleep apnea patients, C-Flex was associated with similar outcomes to standard CPAP. Low compliers receiving CPAP therapy improved their adherence when moving to C-Flex., Trial Registration: ISRCTN Register Identifier: 08065291.

Introduction: Tracheostomy was the treatment of choice for sleep apnoea syndrome before nasal continuous positive airway pressure was developed. The occurrence of sleep apnea syndrome after total laryngectomy is unusual., Case Report: The authors report the case of a 73 year-old man presenting with the symptomatology of sleep apnoea syndrome, several years after a total laryngectomy for cancer. The polysomnographic recording confirmed severe sleep apnoea syndrome with an apnea-hypopnea index of 89. Clinical examination showed a marked reduction in the diameter of the tracheostomy orifice during forced inspiration whilst lying supine. The combination of negative airway pressure and muscle hypotonia during sleep could explain this closure. Use of a silver tracheostomy cannula reversed the symptoms and normalised the apnea-hypopnea index., Conclusion: Sleep apnea syndrome is an unusual complication of total laryngectomy, resulting from collapse of the tracheostomy walls during sleep, which can be treated by the insertion of a silver tracheostomy tube.

During sleep upper airway resistance increases proportionally with a slightly diminished air flow. This can however be compensated for by increasing inspiratory force that further aggravates airway collapse and resistance. Apnea during sleep results from an interaction between the different respiratory and pharynx muscles. Sleep modifies the activity of these muscles leading to increased resistance and muscle fatigue, then eventually histological modifications. Electrical activity is not always proportional to the generated force and muscle shortening, so the effect is not always an increased permeability. In apneic patients, the efficacy of these muscles is preserved but tissue response may be poor. Histological adaptations are variable and depend on the level of the pharynx and the variability of the site of obstruction. This raises the question of electrical stimulation of certain muscles and the choice of the site of stimulation.

EEG color density spectral array enables quick evaluation of sleep. The aim of the study was to evaluate if an easily calculated sleep score based on this method could be used to assess the improvement of sleep after nasal continuous positive airway pressure (CPAP) in patients with sleep apnea syndrome (SAS). Eight hours of sleep are displayed on a single sheet along with EEG amplitude, 2 EEG channel spectra (FFT), electromyogram envelope and electro-oculogram. The x-axis corresponds to time, the y-axis to EEG frequency (range 0-16 Hz), and the color to the frequency power. This system allows the detection of sleep spindles, REM sleep and deep sleep (stages 3 and 4) as well as the evaluation of the sleep cyclic organization and its fragmentation by apnea. Based on these findings a sleep score is calculated. Eight young normal subjects were successively recorded as well as 15 SAS patients and with and without nasal CPAP. During the 1st night, the sleep score was lower in SAS patients than in normal subjects. With CPAP the apnea number decreased and the sleep score returned to normal in all patients except 1. A positive correlation was found between sleep score and duration of stage 2, stage 3 or REM sleep. A negative correlation was found between sleep score and the apnea index. This sleep score enables a quick and reliable evaluation of sleep in patients with SAS before and during nasal CPAP.

Study Objective: The present study was undertaken to validate a system of condensed display of the sleep EEG spectral analysis with a view to simplifying sleep studies in patients affected by sleep apnea syndromes (SAS)., Design: All subjects underwent polysomnography on two consecutive nights using a Respisomnograph. The 8-h EEG, electro-oculogram, and electromyogram were digitalized. A fast Fourier transform was done and successive spectrums were computed resulting in one spectrum for each 20-s period. Then the EEG spectrum was plotted as a Lofard color diagram., Setting: To validate this system we compared a visual analysis of EEG recordings by a trained neurophysiologist with 10-s epochs and a visual analysis of the Lofard diagram by a practitioner with no previous understanding in EEG after only 2 h of instruction. The 8-h recording was divided into 10-min blocks. Each block was staged in function of the amplitude and prevailing frequency of EEG as indicated by the color (wakefulness, light slow wave sleep, deep slow wave sleep, rapid eye movement sleep). The stage of each block was compared with the predominant stage found in this block by the neurophysiologist., Patients: Eight normal adults and 24 patients suffering from SAS were recruited., Results: When all the blocks of all patients were pooled (1,438 blocks), agreement was total in 81 percent, partial in 11 percent, and discordant in 8 percent., Conclusion: This system of spectral analysis representation allows a fast evaluation of quality of sleep and of EEG.

The diagnosis of sleep apnea syndrome (SAS) requires expensive and complex instrumentation. The purpose of the present study was to determine the value of end-tidal CO2 (EtCO2) in screening for sleep apneas. Thirty-nine patients referred to our sleep laboratory because of suspected SAS and ten normal subjects were studied. The EtCO2 was measured using an infrared spectrometer (POET) designed for simultaneous measurement of CO2 and pulse oximetry. In 29 subjects, expired gas was sampled with a nasobuccal mask (Respiron) with lateral orifices. In the other 20 subjects, sampling was done with nasobuccal prongs (Criticare) comprising a four-channel plastic tube to the mouth and the nostrils. Data from an 8-h night were transferred the following day to a microcomputer (Apple Macintosh) for processing. Apnea was defined as an absence of detection of CO2 for more than 10 s. Conventional polysomnography was performed (Respisomnographe). The number of apneas in 8 h and the apnea index (number of apneas in 1 h) were calculated after visual analysis on the screen of the polysomnograph and also with EtCO2 analysis. For recordings made with a nasobuccal mask, the regression curve between the apnea indices computed with EtCO2 and polysomnography was an order 2 polynomial curve (r = 0.76; p < 0.001), with an inflection point at 39 apneas per hour. For recordings with nasobuccal prongs, the correlation was very significant (r = 0.95; p < 0.0001), and the regression curve was linear. The EtCO2 with nasobuccal prongs appears to be a simple and reliable method for screening for SAS.

The purpose of this study was to investigate the effect of a constant infusion rate of terbutaline on circadian bronchial peak expiratory flow rate (PEFR), heart rate and arterial pressure in patients with asthma exacerbation. Fifteen hospitalized asthmatic patients (6 females and 9 males, mean age 43.3 years, mean weight 67.0 kg) were included in this study. In order to reach the desired plasma concentrations of terbutaline immediately, a pharmacokinetic simulation was done. Based on the predicted values thus obtained, an initial 5-min bolus dose of 2.94 micrograms/kg was given to all patients at 7 a.m., i.e. at the beginning of the study. Over the following 24 h (7 a.m. to 7 a.m.), 33 micrograms/kg of terbutaline was infused intravenously at a constant rate with an electric pump. Since severe acute asthma requires corticosteroids, a 40-mg injection of methylprednisolone was given to all patients at 7 a.m. PEFR, heart rate, systolic arterial pressure, side effects and plasma terbutaline levels were recorded at 7 and 10 a.m., 1, 4, 7 and 11 p.m., and 3 and 7 a.m. the following morning. Terbutaline had a significant favorable effect on asthma exacerbation but no circadian rhythm was found in PEFR. Although terbutaline was infused at a constant rate, plasma levels depended on circadian variations.