Abstract: Recent reports have documented an association between patent foramen ovale and obstructive sleep apnea. We report on a 51-year-old man with obstructive sleep apnea and recent stroke who was enrolled in a clinic trial evaluating the efficacy of closure of patent foramen ovale following ischemic stroke. He was randomly assigned to device closure. There was subjective dramatic improvement in sleep-apnea symptoms and objective improvement in polysomnographic testing after device implantation. Aside from a drop in apneas and hypopneas from 181 and 8 on the first polysomnogram to 19 and 0 on the second, there was no significant weight loss nor were there other significant changes in sleep parameters or medications. He stopped using continuous positive airway pressure 2 months after implantation and has had no recurrent sleep complaints during 18 months of follow-up. Further studies evaluating the relationship among patent foramen ovale, sleep apnea, and device implantation are warranted. Citations: Silver B; Greenbaum A; McCarthy S. Improvement in Sleep Apnea Associated With Closure of a Patent Foramen Ovale. J Clin Sleep Med 2007;3(3):295–296

Abstract: What little I remember from high school concerning debating technique consists of the Jesuit adage, “define your terms.” Consequently, I will begin by reviewing the possible criteria by which obstructive sleep apnea (OSA) could be considered “mild” in degree. The various attributes attached to OSA include the presence of symptoms (most frequently, hypersomnia), as well as various metrics obtained from the overnight polysomnogram. The latter include degree of oxyhemoglobin desaturation, which might encompass saturation nadir, total sleep time (TST) below a certain saturation, or mean saturation; respiratory-associated arousal index; or apnea-hypopnea index (AHI). Although the definition of “mild” OSA could be the subject of its own debate, the American Academy of Sleep Medicine has, in fact, taken a position on this issue.1 Two criteria are used: sleepiness, which must be either absent or mild in degree (only occurring in sedentary situations), and AHI, which must fall between 5 and 15 events per hour of sleep. Unfortunately, mild OSA in clinical research has almost universally been defined only in terms of AHI, usually that in the range of 5–15. This definition must then suffice for purposes of this debate.

Abstract: Obstructive sleep apnea (OSA) is a prevalent condition in the general population. However, a majority of individuals with moderate to severe OSA remain undiagnosed. The polysomnogram (PSG) remains the standard test used in the diagnosis of OSA. However, the time, labor, and costs associated with PSG preclude its widespread use as a routine preoperative screening tool. Increased awareness of signs and symptoms associated with OSA and more standardized methods for screening for the condition may help decrease the disparity between prevalence and diagnosis. The authors discuss polysomnography, breathing disorders associated with sleep, signs and symptoms associated with OSA, and associated co-morbidities.

Abstract: A chinstrap alone improved severe obstructive sleep apnea as well as or better than the use of CPAP.

Abstract: Summary Recognizing sleep-disordered breathing is on the rise every year. Manifestations, such as snoring, that were earlier considered mere inconvenients are now acquiring greater importance concerning life quality and social impact. Aim of the study: To compare the clinical history to polysomnogram (PSG) results in the Obstructive Sleep Apnea/Hypopnea Syndrome (OSAHS). Materials and Methods 125 patients were analyzed, in a retrospective study. Specific questionnaires, avaliations of Body Mass Index and Epworth Scale were carried out. Results Among the patients, 75 were males and 50 were females. The main symptom was snoring. 46% had normal PSG, 30% had light OSAHS, 15% moderate and 9% severe OSAHS and it was not observed a correlation between clinical data and PSG results. Concerning clinical symptoms, only insomnia has shown relevance when univariably analyzed in normal and light OSAHS patients (p Conclusion the clinical history, per se, is not sufficient to define OSAHS' diagnosis or it's severity.

Abstract: A fall in body temperature due to circadian rhythms causes drowsiness and increases the propensity to sleep from the evening to midnight. As one of the sources of declining body temperature, the occipital region was cooled with a water pillow in this study, and the effect of this cooling technique on the sleep process and subjective ratings of sleep was analyzed. Seven university students whose sleep latency was more than 30 min slept using a pillow with a surface temperature 16°C (iced water condition) or 26°C (room temperature water condition), respectively. The iced water decreased the axilla temperature faster than the water at room temperature. A polysomnogram analysis indicated that sleep latency was significantly shorter when iced water was used compared to when cool water at room temperature was used. In addition, the iced water improved the participants’ subjective quality of sleep, including falling asleep and sleep maintenance. These results suggest that cooling the occipital region might be effective in promoting sleep onset and sleep maintenance.

Abstract: A typical polysomnogram (Current Procedural Terminology code 95810) includes recording of an electroencephalography (EEG), an electro-oculogram (EOG), an electromyogram (EMG) of chin muscles, oronasal airflow, chest and abdominal movements, leg movements, snoring, and oximetry. Following is a discussion of some of the aspects of polysomnography.

Abstract: The Multiple Sleep Latency Test (MSLT) is an important tool in the evaluation of excessive daytime sleepiness. It is indicated for the diagnosis of narcolepsy and the evaluation of idiopathic hypersomnia.1 However, the MSLT results can be affected by a variety of extraneous variables that must be controlled or minimized to obtain interpretable diagnostic data.2 Prior sleep deprivation is the most worrisome and difficult to monitor extraneous variable. The article “Nightly Sleep Duration in the Two-Week Period Preceding Multiple Sleep Latency Testing” in this edition, examines this issue by comparing sleep duration from self-reported average nightly sleep time, sleep logs, and actigraphy. Results showed that subjective estimates of sleep time were longer than the time measured by actigraphy. Moreover, actigraphy was the only measure that showed a low but significant correlation with MSLT results. It was suggested that actigraphy might be a better way of measuring sleep duration before the MSLT. This article touches on several basic questions surrounding prior sleep duration and the MSLT. The first question is when should an MSLT be performed? It is common for sleep duration to vary across the week with partial sleep deprivation on work nights followed by “catch up” on the weekend. This pattern was evident in the participants in this study, who also reported about 4 naps (range 0–14) per week. Not surprisingly, the patients slept the longest (7.4 hr) on the polysomnogram (PSG) night when given the opportunity. Having this information, a clinician should consider a diagnosis of insufficient sleep and recommend increasing sleep time to eliminate excessive daytime sleepiness before performing an MSLT. If this is not effective, an MSLT would be warranted if the history could support a diagnosis of narcolepsy. In practice, however, estimates of sleep durations in the week prior to MSLT are not usually obtained, so the clinician is not aware of the potential role of sleep deprivation. This study dramatically demonstrates what clinicians could be missing. Although military personnel with truncated sleep opportunities are not typical patients, it is well established that most Americans are sleep deprived.3 The next question is how should prior sleep time be measured? This study compared actigraphy, a single subjective estimate of sleep duration, and sleep time from measured line lengths on sleep logs. Actigraphy showed the shortest total sleep time (0.5–1.5 hr less) in the 2 weeks prior to MSLT compared to the other measures. On the PSG night, actigraphy also showed shorter sleep duration than sleep measured by PSG. Sleep log estimates were not obtained on the PSG night. These data make it difficult to draw conclusions because the measures are not really comparable, and data are not available for all measures. This last question is how much sleep is adequate? Adequate sleep is a requirement for correct interpretation of MSLT, but it is not defined.4 Indeed, it cannot be defined because it varies among individuals. Confusion arises because a minimum of 6 hours of sleep in the preceding PSG is required in the International Classification of Sleep Disorders-2 for performing the MSLT.1 This lower limit is not the same as adequate sleep. The lower limit was derived from the fact that narcolepsy patients often have very fragmented sleep and may not be able to get more than 6 hours of sleep at night. Six hours was not intended as an adequate amount of sleep in most cases, since most adults need 7–8 hours of sleep, while teenagers and some adults need more. Adequate sleep should allow a person to function well throughout the day without falling asleep or fighting sleepiness. Unfortunately, the sleep clinician will not know how many hours of sleep are adequate for a patient by looking at sleep duration in the weeks prior to the MSLT. The answers to these questions are still largely unknown. However, it is clear that a thorough sleep history combined with information about the prior week's sleep duration from any measure can help the clinician answer all of these questions. Moreover, given the large sleep debt in the country, a reasonable first step in most cases would be to prescribe increased sleep time for a week or two before deciding to do an MSLT. This may be beneficial to the patient, could provide valuable clinical information, and help assure more “adequate” prior sleep if an MSLT is performed.

Abstract: Study Objectives:To demonstrate that fetal heart rate measured by ultrasound can be successfully captured and monitored throughout the nocturnal polysomnogram.Methods:Fetal heart rate by ultrasound...

Abstract: To determine if bed and wake times can be determined from continuous ECG recordings in the elderly, PSG (polysomnogram), ECG channels were extracted and scanned on a Holter analyzer for N=56 participants (age 76plusmn3) in the Sleep Heart Health Study who had 2 PSGs 5 years apart. Bed and wake times were determined from a combination of 5-min averaged HR and HRV patterns and from HR tachograms of normal-to-normal intervals. Bed and wake times were also extracted from the PSGs. PSG- and HRV bed and wake times were compared via paired t-tests and correlation analysis. Correlations between PSG- and HRV-determined bed and wake times were les0.95. HRV-derived bed and wake times were slightly (4plusmn7 min) earlier for and 5plusmn11 min earlier the 2 PSGs, ples0.001. Mean PSG and ECG-based wake times were closer (12plusmn20s earlier, p=0.069 and 2plusmn8 min later, p=0.049 for the 2 PSGs). Therefore, determination of bedtime and wake time patterns in large Holter cohorts without activity diaries is feasible.

Abstract: A 60-year-old Caucasian man presents to a sleep disorders clinic with a chief complaint of abnormal body movements and talking during sleep. He is accompanied by his wife, who reports that the patient frequently shouts, punches, and kicks during sleep. The episodes began 4 to 5 years ago. Initially, they were sporadic but have been occurring once or twice a week lately, usually in the later part of the night. Three nights ago, the patient punched his wife violently in sleep and then pushed her away while yelling loudly. When she woke him up, he said that he was dreaming that he was in a jungle, fighting a bear. She is now afraid to sleep with him and sleeps in a different bed. The patient feels embarrassed and says that he has frequently experienced dreams in which he fights an animal or a monster. He denies any daytime complaints. The patient has a history of hypertension and hypercholesterolemia. His medications include metoprolol 50 mg twice a day and simvastatin 20 mg once a day. He smoked 1 pack of cigarette a day for 35 years until he quit 8 years ago. He drinks 1 to 2 beers on the weekend but denies alcohol abuse. On examination, the patient is an overweight male. The remainder of the findings on physical examination are normal. The patient undergoes overnight polysomnography. The accompanying figure shows an epoch from the polysomnogram. The sleep technician notes that the patient was kicking and shouting in sleep during this episode. Figure 1 An epoch from the patient's polysomnogram. EOG refers to electrooculogram; EMG, electromyogram; EKG, electrocardiogram. Which of the following is true about this disorder? The dreams are usually associated with abrupt awakenings and a feeling of panic, with full alertness occurring immediately upon awakening. The patient has a higher likelihood of developing multiple system atrophy. The patient has a higher likelihood of having iron-deficiency anemia. Secondary enuresis and tongue-biting are common features. Answer: B Rapid eye movement (REM) sleep behavior disorder (RBD) is a parasomnia characterized by a loss of the normal skeletal muscle atonia during REM phase of sleep. The disorder frequently manifests as enactment of dreams, resulting in shouting, flailing of arms, and moving and kicking during sleep, and may result in injury to self and to others.1 It is common for people affected by this disorder to report a history of vivid, intense, and violent dreams. RBD is predominantly a disease of older men (older than 50 years of age), with the mean age at presentation in 1 series being approximately 64 years.2 The polysomnogram frequently reveals augmented phasic or tonic muscular activity during REM sleep. The accompanying epoch demonstrates increased activity in chin -electromyogram and leg-electromyogram leads during REM stage, along with technician's notation, “talking in sleep.” RBD may be idiopathic in approximately 60% of cases, other cases being associated with neurologic disorders such as ischemic cerebrovascular disease, subarachnoid hemorrhage, Parkinson disease, multiple system atrophy, progressive supranuclear palsy, Shy-Drager syndrome, olivopontocerebellar degeneration, and multiple sclerosis. Many patients with “idiopathic” RBD will develop neurodegenerative disorders many years after the onset of parasomnia (choice B).3 Clonazepam is an effective therapy for most persons with RBD.1 This disorder should be differentiated from nightmares, which can occur at any age and are usually followed by abrupt awakenings accompanied by a sensation of fear or panic (choice A). Iron-deficiency anemia (choice C) is associated with restless leg syndrome and not RBD. Secondary enuresis and tongue biting (choice D) are features of epilepsy as opposed to RBD. Although sleep-related epilepsy would be a consideration in persons with focal limb movements during sleep, the history in this case is typical of RBD.

Abstract: A 73-year-old male presents with hypersomnolence and witnessed pauses in breathing during sleep lasting 30–60 seconds He was diagnosed with obstructive sleep apnea in 1996 and underwent uvulopalatopharyngoplasty (UPPP) His symptoms re-emerged 2 years later Multiple sleep studies done since then demonstrated Cheyne Stokes breathing He was treated with continuous positive airway pressure (CPAP), bilevel PAP (with and without backup rate), and/or supplemental oxygen but he continued to have unabated diurnal hypersomnolence and his wife noted incomplete resolution of pauses in breathing He had history of atrial fibrillation, coronary artery disease, and permanent pacemaker placement A representative tracing from his diagnostic polysomnogram is shown below (display range 240 seconds) Which of the following treatments is likely to be MOST effective in treating his sleep disordered breathing? Beta blockers Adaptive Servoventilation Automatically adjusting PAP Theophylline Supplemental CO2 Answer B Adaptive servoventilation

Abstract: Objective Our goal was to validate the WatchPAT in the diagnosis of obstructive sleep apnea. Study Design We conducted a prospective, blinded, nonrandomized clinical trial. Methods Patients with suspected obstructive sleep apnea scheduled for an overnight level I polysomnogram were offered enrollment in a study to compare the WatchPAT (Itamar Ltd, Israel) device with polysomnography. Patients wore the WatchPAT device simultaneously while undergoing polysomnography during evaluation in the sleep lab. Results Thirty-seven patients participated in the study. They had a mean age of 50.1 years (range, 31−73 years) and mean body mass index of 34.6 kg/m2 (range, 21.2−46.8 kg/m2). There was high correlation between the polysomnogram and WatchPAT apnea-hypopnea index (r = 0.9288; 95% confidence interval = 0.8579−0.9650, P Conclusion The WatchPAT showed a high correlation with the polysomnogram in apnea-hypopnea index, lowest oxygen saturation, and sleep time. Significance It’s use as a reliable tool in the diagnosis of Obstructive Sleep Apnea.

Abstract: Age is probably the single most crucial factor determining how humans sleep Age and level of vigilance significantly influence the electroencephalogram (EEG) and the polysomnogram (PSG) The Pediatric Task Force provide an evidence-based review of the age-related development of the polysomnographic features of sleep in neonates, infants, and children, assessing the reliability and validity of these features, and assessing alternative methods of measurement We used this annotated supporting text to develop rules for scoring sleep and arousals in infants and children A pediatric EEG or PSG can only be determined to be normal by assessing whether the EEG patterns are appropriate for maturational age Sleep in infants at term can be scored as NREM and REM sleep because all the polysomnographic and EEG features of REM sleep are present and quiet sleep, if not NREM sleep, is at least "not REM sleep" The dominant posterior rhythm (DPR) of relaxed wakefulness increases in frequency with age: (1) 35-45 Hz in 75% of normal infants by 3-4 months post-term; (2) 5-6 Hz in most infants 5-6 months post-term; 3) 6 Hz in 70% of normal children by 2 months of age; and 3) 8 Hz (range 75-95 Hz) in 82% of normal children age 3 years, 9 Hz in 65% of 9-year-olds, and 10 Hz in 65% of 15-year-old controls Sleep spindles in children occur independently at two different frequencies and two different scalp locations: 110-1275 Hz over the frontal and 130-1475 Hz over the centroparietal electrodes; these findings are most prominent in children younger than 13 years Centroparietal spikes are often maximal over the vertex (Cz), less often maximal over the left central (C3) or right central (C4) EEG derivation About 50% of sleep spindles within a particular infant's PSG are asynchronous before 6 months of age, 30% at 1 year Based on this, we recommend that: (1) sleep spindles be scored as a polysomnographic signature of NREM stage 2 sleep (N2) at whatever age they are first seen in a PSG, typically present by 2 to 3 months post-term; (2) identify and score sleep spindles from the frontal and centroparietal EEG derivations, especially in infants and children younger than 13 years NREM sleep in an infant or child can be scored if the dominant posterior rhythm occupies 20% of the 30-second epoch contain 05 to 2 Hz >75 microV (usually 100-400 microV) activity as N3 The DPR should be scored in the EEG channel that is best observed, (typically occipital), but DPR reactive to eye opening can be seen in central electrodes Because sleep spindles occur independently over the frontal and central regions in children, they should be scored whether they occur in the frontal or central regions Because sleep spindles are asynchronous before age 2 years, simultaneous recording of left and right frontal and central activity may be warranted in children 1-2 years of age Simultaneous recording of left, right, and midline central electrodes may be appropriate because of the asynchronous nature of sleep spindles before age 2 years, but reliability testing is needed Evidence has shown that the PSG cannot reliably be used to identify neurological deficits or to predict behavior or outcome in infants because of significant diversity of results, even in normal infants Normal sleep EEG patterns and architecture are present in the first year of life, even in infants with severe neurological compromise Increasing evidence suggests that sleep and its disorders play critical roles in the development of healthy children and healthy adults thereafter Reliability studies comparing head-to-head different scoring criteria, recording techniques, and derivations are needed so that future scoring recommendations can be based on evidence rather than consensus opinion We need research comparing clinical outcomes with PSG measures to better inform clinicians and families exactly what meaning a PSG has in evaluating a child's suspected sleep disorder