Showing papers on "Polysomnography published in 1989"

Prevalence of every night snoring and obstructive sleep apnoeas among 30-69-year-old men in Bologna, Italy.

Abstract: — An epidemiological survey of the prevalence of snoring and sleep apnoeas was performed on 3479 30-69-year-old men living in Bologna, north-east Italy. First a postal questionnaire was sent. It was returned with appropriate answers by 1170. A 20% random sample of those who did not answer were invited by telephone to return the questionnaire. Among these groups 119 (10%) and 19 (5.6%) respectively answered that they always snored. A random sample of 40 every-night snorers were studied by polysomnography. Based on the frequency of every-night snoring and the results of polysomnography we estimated that the minimal prevalence of sleep apnoea among 30-69-year-old men was 2.7% considering an apnoea + hypopnoea index of 10 or more pathological. According to the Lugaresi classification we had a 2.5% prevalence of heavy snorers’ disease (HSD) Stage 1 or higher. These figures indicate that obstructive sleep apnoea during sleep is a major public health problem.

Maxillofacial surgery and obstructive sleep apnea: a review of 80 patients.

Abstract: To determine the effectiveness of the surgical treatment of obstructive sleep apnea, we retrospectively evaluated 80 patients. One group consisted of 55 patients who had undergone a limited osteotomy of the anterior mandible: inferior sagittal osteotomy with hyoid myotomy and suspension. Important criteria for the selection of these patients were normal pulmonary function, normal mandibular skeletal development, and the absence of morbid obesity. Polysomnography revealed that 37 patients (67%) had responded to the surgical treatment and 18 patients (33%) had not. The second group of 25 patients, selected for morbid obesity, severe mandibular deficiency, and failure of other surgical procedures, had undergone maxillomandibular osteotomy with hyoid advancement. All patients in the second group showed good results, as determined by polysomnography.

Evaluation of the upper airway by computerized tomography in patients undergoing uvulopalatopharyngoplasty for obstructive sleep apnea.

Abstract: This study utilized computerized tomography (CT) to evaluate the effects of uvulopalatopharyngoplasty (UPPP) on upper airway (UA) dimensions. The objectives were to determine whether CT scan results would be useful in identifying UA characteristics predictive of a good surgical result as well as elucidating reasons for failure of this operative procedure. Twenty-three male patients with obstructive sleep apnea (OSA) had CT scans and polysomnography performed before and after UPPP. Preoperatively, the apnea plus hypopnea index (AHI) was 64 ± 6 per hour and the minimal UA cross-sectional area (Amin) was located at 10 and 20 mm below the level of the hard palate in 87% (20 of 23) of the patients. Uvulopalatopharyngoplasty more than doubled UA cross-sectional areas at these two proximal levels. In contrast, the hypopharyngeal segment located 50 to 70 mm below the hard palate decreased in cross-sectional area by 23 to 25% after surgery. Eight patients (35%) had a good response to UPPP based on a greater than 5...

Gastroesophageal reflux associated with respiratory abnormalities during sleep.

Abstract: To determine whether gastroesophageal reflux (GER) might be a factor in the pathogenesis of apnea in certain infants, we analyzed the frequency of prolonged central apnea (greater than 15 s) and of numerous irregularly repeated short apneas (5-15 s) ("respiratory dysfunction") in infants with an apparent life-threatening event (ALTE) (group 1, n = 62), in control infants (group 2, n = 387), and in infants with GER pathologic findings (group 3, n = 60). Finally, the incidence of GER was analyzed in 76 infants with a respiratory dysfunction during sleep (group 4). Gastroesophageal reflux was investigated using 24-h esophageal pH monitoring; respiration during sleep was investigated by polysomnography. The pH monitoring data and results of sleep investigation were analyzed in a double-blind study. A great number of infants who had an ALTE appeared to suffer from GER (42%, 26 of 62 infants), especially if the ALTE occurred while the infant was awake (52%, 14 of 27 infants). In the control infants, pH monitoring data were abnormal in 8.5%; respiratory dysfunction was observed in 5%. In those with a respiratory dysfunction, GER was detected in 75% (15 of 20 infants). In those with GER, respiratory dysfunction was observed in 45% (15 of 33 infants). In groups 3 and 4, respiratory dysfunction was associated with abnormal pH data in 40-43%. If, in the infants with a respiratory dysfunction, the GER pathologic symptoms were treated efficiently (normalization of pH data), respiratory dysfunction disappeared in 92%.(ABSTRACT TRUNCATED AT 250 WORDS)

Obstructive sleep apnea syndrome in sickle cell disease.

Abstract: We present a series of 21 children with obstructive sleep apnea syndrome and sickle cell disease (SCD) Thirteen patients underwent adenotonsillectomy with resolution of symptoms and improvement in alveolar hypoventilation Adenotonsillectomy involves significantly increased risks in patients with SCD We present our protocol for management of these difficult surgical patients, including vigorous hydration and transfusion therapy Polysomnography has proven valuable both in diagnosis and in identifying severely affected patients Increased end tidal alveolar carbon dioxide during sleep has proven to be a significant predictor of disease, while oxygen saturation monitoring was shown to be unreliable The incidence of adenotonsillar hypertrophy (ATH) in SCD appears increased and not related to infectious diseases We suggest that ATH represents a part of the natural course of compensatory lymphoid tissue enlargement in children with SCD

Polysomnographic assessment of DIMS: empirical evaluation of its diagnostic value.

Abstract: This investigation examined the diagnostic value of polysomnography (PSG) for evaluating disorders of initiating and maintaining sleep (DIMS). The sample consisted of 100 outpatients who presented to the Duke Sleep Disorders Center with a complaint of chronic insomnia. All patients were given comprehensive medical, psychiatric, behavioral, and ambulatory PSG evaluations. Sleep disorder diagnoses were assigned using the criteria of the Association of Sleep Disorders Centers. Overall, PSG yielded important diagnostic information in 65% of the sample: 34% were given a primary sleep disorder diagnosis that was heavily dependent on PSG data [periodic movements of sleep (PMS) = 25%, apnea = 3%, and subjective insomnia = 6%]; 15% were given a secondary diagnosis of one of these three disorders; and PSG ruled out suspected PMS in 9% and sleep apnea in 7% of the sample. Patients greater than 40 years of age had a significantly higher rate of positive PSG findings than younger patients. Using only the clinical exam, two experienced sleep clinicians were able to predict only 14 of 25 PMS cases and one of three cases of sleep apnea. Based on these data, we suggest using PSG routinely with older insomniacs and with younger patients who fail initial treatment.

The effects of L-dopa on periodic leg movements and sleep organization in narcolepsy.

Abstract: A large proportion of narcoleptic patients have periodic leg movements (PMS) in sleep. The contribution of these movements to the nocturnal sleep disturbance observed in narcoleptics remains a controversial issue. The aim of the present study was to look at the sleep organization of narcoleptic patients before and after suppression of periodic leg movements with l-dopa. L-dopa and a placebo were administered in a double-blind fashion to six narcoleptic patients. Each treatment period lasted 2 weeks and the treatment order was reversed for one-half of the subjects. The effects of l-dopa and placebo were evaluated by polysomnography. A significant reduction of PMS was seen after treatment with l-dopa, but this treatment did not improve sleep organization. On the contrary, l-dopa increased wake time after sleep onset. This result supports the hypothesis that PMS does not play a major role in the nocturnal sleep disruption observed in narcolepsy. It also supports the hypothesis that dopaminergic mechanisms play a role in the physiopathology of PMS.

Sleep EEG evaluation: a comparison of results obtained by visual scoring and automatic analysis with the Oxford sleep stager.

Abstract: Oxford Medical has introduced an automatic sleep stager based on the stage-scoring criteria by Rechtschaffen and Kales. With our study we intended to examine whether the results of the stager (version 3.0) match those of the visual evaluation by two independent raters. We also wanted to test the reliability of this automatic sleep stage-scoring system. Ten somnopolygrams of subjects without sleep disturbances served as a basis for the comparison. Each sleep recording was scored twice automatically by the stager, twice visually by the first rater, and once by the second rater. The two automatic analyses of the somnopolygrams differed by 4.3% in a total of 13,850 epochs (1 epoch delta 20 s) regarding sleep stage scoring. The difference between the first and the second visual evaluation by the same rater amounted to 5.7%, whereas the results of the two independent raters deviated by 8.7%. Compared with the results of the visual analysis reached as a consensus by both raters--the so-called optimized visual analysis--the stager showed a 26.9% difference. The automatic analysis scored fewer epochs as stages wake, rapid eye movement (REM), and 2 and more as stages 1, 3, and 4. The sleep stager's frequent difficulty in identifying stage wake correctly as well as its incorrect allocation to other stages--mainly stage REM--could lead to misinterpretations of sleep recordings, whereas the increase in stages 1, 3, and 4, as compared with visual scoring, was negligible.

Oxygen treatment of sleep hypoxaemia in Duchenne muscular dystrophy.

Abstract: Patients with Duchenne muscular dystrophy develop progressive ventilatory muscle weakness and often die of respiratory complications. Recurrent, often profound, hypoxaemia has been shown in a previous study by this group to occur during rapid eye movement (REM) sleep in these patients before they develop sleep symptoms. In this study the efficacy and physiological effects of nocturnal oxygen in such patients have been assessed. Seven patients with Duchenne muscular dystrophy (age range 16-22 years; mean vital capacity 1.37 litres) with normal arterial blood gas tensions when awake were investigated by standard overnight polysomnography on an acclimatization night followed by two successive nights on which they received room air and nasal oxygen (2 litres/min) respectively in random order. Total sleep time, proportion of REM and non-REM sleep, and frequency and duration of arousals were similar on the two nights. When breathing air six of the seven subjects developed oxygen desaturation of more than 5% during REM sleep. With oxygen only one subject showed any oxygen desaturation exceeding 2.5%. Oxygen desaturation was associated with periods of hypopnoea or cessation of respiratory effort. The mean duration of episodes of hypopnoea and apnoea was prolonged during oxygen breathing by 19% and the mean duration of episodes during REM sleep by 33% (the proportion of REM sleep associated with hypopnoea and apnoea increased in all subjects). Heart rate in non-REM sleep fell by 9.3%; heart rate variation in REM and non-REM sleep was unchanged. These acute studies show that oxygen reduces the sleep hypoxaemia associated with respiratory muscle weakness; whether long term treatment will be possible or desirable is not clear as oxygen potentiates the underlying ventilatory disturbance.

Nightcap: a home-based sleep monitoring system

Abstract: In an attempt to offer a home-based adjunct to traditional sleep laboratory methods, we developed a system to monitor sleep, and to predict algorithmically non-rapid-eye-movement (NREM) and rapid-eye-movement (REM) sleep states, using eye and body motility as the only parameters. Eye movement was measured using a strain gauge transducer applied to the eyelid of subjects, while body movement was measured using a piezo-ceramic phono cartridge. Both transducers were mounted on a tennis headband, along with electronics that amplified, filtered, and digitized the signals. Digital pulse signals were input to a portable computer in minute-long epochs, and state-predicting algorithms were run based on this motility data. Four subjects were monitored in the sleep lab with both our headgear and standard polysomnography. Hand-scored sleep records were compared with those predicted by computer algorithms. Algorithm-predicted states agreed with hand-scored ones an average of 85.57% (SEM +/- 1.7%). Mean values for sleep onset and REM latency were within 1.6 and 10.8 min of polysomnographic records, respectively. These results are encouraging, and suggest that this system could provide a comfortable, subject operable, and inexpensive method for the evaluation of sleep at home.

Benefit of nasal CPAP in obstructive sleep apnea is due to positive pharyngeal pressure.

Abstract: The purpose of this study was to determine if the mechanism of nasal continuous positive airway pressure's (CPAP's) effectiveness is to act as a pneumatic splint or to increase functional residual capacity (FRC) and consequently, upper airway caliber Four subjects with obstructive sleep apnea underwent 3 nights of polysomnography: night 1, control; night 2, nasal CPAP; night 3, external subatmospheric pressure (ESAP) ESAP, a negative pressure body suit, increases FRC We measured the changes in FRC with nasal CPAP and ESAP using the weighted spirometer technique The dose used for the ESAP night was the dose that produced the same FRC as the subject's prescribed nasal CPAP dose The mean number of arousals and the respiratory events index were higher on ESAP and control nights Less severe oxygen desaturation occurred during non-rapid-eye-movement sleep on the nasal CPAP and ESAP nights These preliminary results show that increasing FRC alone does not account for the effectiveness of nasal CPAP, and splinting of the collapsible upper airway is necessary

Relationship of nocturnal bronchoconstriction to sleep stages.

Abstract: The possible role of sleep stages in the pathogenesis of nocturnal asthmatic attacks is still under debate because previous studies suffered methodologic limitations that prevented the possibility of providing a clear-cut answer to the question. To evaluate the relationship of nocturnal asthma to sleep, eight asthmatics with unstable asthma (seven with history of nocturnal wheeze) and four reference subjects were submitted to all-night polysomnography, including the continuous evaluation of esophageal and supraglottic pressure (with two catheters) as well as of airflow (with a face mask), so as to derive total lung resistance, supraglottic resistance, and, by subtraction lower respiratory resistance (Rlr). Stage 3-4 was characterized by the highest peaks in Rlr and by longer episodes of bronchoconstriction; conversely, neither the onset nor the remission of the latter were specifically related to any sleep stage. Considering episodes remitted with an awakening. Stage 3-4 was marked by higher Rlr peaks than during REM sleep. We conclude that sleep plays a contributory role in the multifactorial pathogenesis of nocturnal asthma, with a higher susceptibility during slow-wave sleep, probably related to a decreased responsivity to resistive loads.

Decrease in delta sleep in growth hormone deficiency assessed by a new power spectrum analysis.

Abstract: Seven pituitary dwarfs between 18 and 28 years old with congenital absence of growth hormone, i.e., isolated growth hormone deficiency (IGHD), were examined with polysomnography. Power spectrum analyses of the delta band showed a significant decrease in power in the delta sleep in the IGHD patients compared with the controls. Power spectrum analyses add a new dimension to the description of sleep, as it evaluates, not only frequency of the electroencephalogram (EEG) in time but also the amplitude of the EEG signal. This means that sleep of same quantity can have different powers; for example, 15 min of stage 4 in one person can have another quality than 15 min of stage 4 in another person. An additional observation was that the power in the delta band in the normal young controls showed a correlation to age, with significant decrease within a 10-year period.

Breathing abnormalities during sleep in patients with chronic heart failure.

Abstract: Polysomnography was carried out in 11 adult outpatients with stable chronic heart failure (CHF) due to valvular heart disease in order to investigate respiratory abnormalities during sleep. The subjects consisted of 6 males and 5 females and their ages ranged from 54 to 76 years. A coexisting central dominant sleep apnea syndrome (SAS) was found in 4 males, 3 of whom had evidence of nasal obstruction. A successful mitral valve replacement in one patient with central dominant SAS was associated with a reduction in the frequency of sleep apnea. The results suggest complications caused by respiratory abnormalities during sleep are common and should be considered in the management of patients with CHF.

Cerebral anoxic attacks in sleep apnea syndrome.

Abstract: In a 52-year-old man who presented with an obstructive sleep apnea (OSAS) syndrome, we observed cerebral anoxic attacks during rapid eye movement (REM) sleep. Polysomnography showed that the attacks were due to severe hypoxia provoked by apneas lasting up to 220 s. Electroencephalogram (EEG) and clinical features clearly differentiate cerebral anoxic attacks from epileptic seizures. The length of apneas in our patient is very unusual, indicating an impairment of the mechanism terminating apneas. The cause of this impairment is unknown. However, this case report documents a possible pathogenetic mechanism other than heart arrhythmias responsible for sudden death or coma arising during sleep.

Psychosis in Sleep Apnoea

Abstract: A 30-year-old man presenting with intellectual impairment and recurrent psychotic episodes was subsequently found to have suffered from a chronically untreated obstructive sleep apnoea syndrome. Polysomnography revealed sleep fragmentation, slow wave sleep deprivation and abnormal arterial oxygen desaturation. Tonsillectomy led to complete resolution of sleep apnoea and remission of psychosis at 2 years' follow-up, but his apparent intellectual impairment persisted. The limited literature on psychosis associated with sleep apnoea is briefly reviewed.