False-positive cases in multiple sleep latency test by accumulated sleep debt.

PURPOSE: Multiple sleep latency test (MSLT) is performed as objective assessment of sleepiness, on the following day after polysomnography (PSG). In most clinics, patients are required to stay for 2 days. However, if patients have chronic sleep debt before the examination, even if they get adequate nocturnal sleep during the initial PSG, their sleep debt would not be fully resolved, affecting MSLT results. This may lead to improper administration of psycho-stimulant medication. To clarify the sleep debt for the patients who showed short sleep latencies, we compared the mean sleep latencies of MSLTs. METHODS: Twelve hypersomnolent males, who underwent MSLTs (1st MSLT with 1 night and 2nd MSLT with more than 3 nights), were enrolled. We selected these cases based on the longer total sleep time on PSG night compared to the mean total sleep time on pre-examination sleep logs and shortened sleep latencies on PSG. To evaluate the effect of the sleep debt for the patients who showed short sleep latencies, we extended their hospitalization or re-hospitalized them. RESULTS: The mean sleep latency of 1st MSLT was 5.8 minutes and that of 2nd was 13.9 minutes (P < .001). Among these 12 cases, 5 cases altered from short to normal sleep latencies at the 2nd MSLT. These 5 cases were prevented from over-diagnoses by the extension of evaluations. CONCLUSIONS: The sleep debt may produce false-positive results when patients are examined by standard PSG and MSLT. Accumulation of sleep debt will cause shortened sleep latencies in the following nights. Patients should be advised to extend their hospitalization before PSG and MSLT to reduce the chronic sleep debt for accurate diagnosis of hypersomnia.

Prevalence of sleep-disordered breathing in Japanese medical students based on type-3 out-of-center sleep test.

BACKGROUND: Sleep-disordered breathing (SDB), especially obstructive sleep apnea disorder (OSA), is thought to mainly affect men over the age of 40. Following findings that Asian people are more likely to experience severe OSA, regardless of obesity, we investigated the prevalence of SDB and OSA in a larger sample and in more younger age groups than those described in previous reports. METHODS: Between 2011 and 2016, 487 medical students (358 males, mean age 24.8 ± 1.9 years; 129 females: mean age 23.8 ± 1.6 years) underwent an out-of-center sleep test using a type-3 portable monitor. The results were analyzed visually. RESULTS: The mean ± standard deviation of the respiratory event index (REI: events/hour of monitoring) was 5.4 ± 6.7 (6.7 ± 7.5 in male participants, 2.6 ± 2.1 in female participants). There were 170 participants (36.6%) with an REI≥5, including 158 male participants (46.9%) and 12 female participants (9.1%). SDB or undefined OSA with low REI (15 > REI≥5) was observed in 141 participants (30.4%), defined OSA with moderate REI (30 > REI≥15) in 19 participants (4.1%), and defined OSA with high REI (REI≥30) in 10 participants (2.2%). Among the male students, 129 had low REI (38.3%), 19 had moderate REI (5.6%), and 10 had high REI (3.0%). All female participants with OSA events (9.4%) had a low REI. CONCLUSIONS: The prevalence of OSA in Japanese young adults, especially males under 30 years old, is similar or even higher than that in older age groups described previously. Thus, an aggressive sleep study for SDB might be necessary for the younger generation in the Asian population.

Effects of CPAP treatment interruption due to disasters: patients with sleep-disordered breathing in the Great East Japan Earthquake and tsunami area.

INTRODUCTION: The 2011 Great East Japan Earthquake caused major disruptions in the provision of health care, including that for patients with sleep-disordered breathing (SDB) using a nasal continuous positive airway pressure (nCPAP) device. This study investigated the ability of SDB patients to continue using the nCPAP device in the weeks immediately following the earthquake, whether inability to use the nCPAP device led to symptom relapse, and measures that should be taken to prevent disruptions in nCPAP therapy during future disasters. Hypothesis If nCPAP devices cannot be used during disasters, SDB patients' health will be affected negatively. METHODS: Within 14 days of the disaster, 1,047 SDB patients completed a questionnaire that collected data regarding ability to use, duration of inability to use, and reasons for inability to use the nCPAP device; symptom relapse while unable to use the nCPAP device; ability to use the nCPAP device use at evacuation sites; and recommendations for improvement of the nCPAP device. RESULTS: Of the 1,047 patients, 966 (92.3%) had been unable to use the nCPAP device in the days immediately following the earthquake. The most common reason for inability to use the nCPAP device was power failure, followed by anxiety about sleeping at night due to fear of aftershocks, involvement in disaster-relief activities, loss of the nasal CPAP device, and fear of being unable to wake up in case of an emergency. Among the 966 patients, 242 (25.1%) had experienced relapse of symptoms, the most common of which was excessive daytime sleepiness (EDS), followed by insomnia, headache, irritability, and chest pain. CONCLUSION: Developing strategies for the continuation of nCPAP therapy during disasters is important for providing healthy sleeping environments for SDB patients in emergency situations.

Cerebral air embolism treated with hyperbaric oxygen therapy following percutaneous transthoracic computed tomography-guided needle biopsy of the lung.

A 71-year-old man presented with cough and sputum for 12 months. Chest radiography showed a homogeneous opacity in the right lower lobe. Computed tomography (CT) showed a nodular opacity, 2 cm in diameter, in the posterior segment of the right lower lobe. Mild emphysematous changes were also seen. With the patient in a prone position, a 19-gauge 7.8-cm introducer was placed in the lesion during a single inspiratory breath-hold. A coaxial 20-gauge automated needle was inserted through the introducer using a biopsy gun. Although the patient did not complain of any symptoms, postbiopsy CT showed air in the left ventricle and ascending aorta. After 5 h of bed rest, we found weakness in his left lower extremity. He was transferred to a hyperbaric oxygen chamber and recovered the next day. Air embolism is a rare, potentially fatal complication of percutaneous lung biopsy. Although the true effect of hyperbaric oxygen therapy is controversial, knowledge regarding the prompt management of such cases may help radiologists who perform this procedure.