Biomedical subjects

M Gugger

Publications and source records attributed to M Gugger.

At least 37 records · Page 2Linked to original sources

PubMed2001

Molecular characterization of planktic cyanobacteria of Anabaena, Aphanizomenon, Microcystis and Planktothrix genera.

Toxic and non-toxic cyanobacterial strains from Anabaena, Aphanizomenon, Calothrix, Cylindrospermum, Nostoc, Microcystis, Planktothrix (Oscillatoria agardhii), Oscillatoria and Synechococcus genera were examined by RFLP of PCR-amplified 16S rRNA genes and 16S rRNA gene sequencing. With both methods, high 16S rRNA gene similarity was found among planktic, anatoxin-a-producing Anabaena and non-toxic Aphanizomenon, microcystin-producing and non-toxic Microcystis, and microcystin-producing and non-toxic Planktothrix strains of different geographical origins. The respective sequence similarities were 99.9-100%, 94.2-99.9% and 99.3-100%. Thus the morphological characteristics (e.g. Anabaena and Aphanizomenon), the physiological (toxicity) characteristics or the geographical origins did not reflect the level of 16S rRNA gene relatedness of the closely related strains studied. In addition, cyanobacterial strains were fingerprinted with repetitive extragenic palindromic (REP)- and enterobacterial repetitive intergenic consensus (ERIC)-PCR. All the strains except two identical pairs of Microcystis strains had different band profiles. The overall grouping of the trees from the 16S rRNA gene and the REP- and ERIC-PCR analyses was similar. Based on the 16S rRNA gene sequence analysis, four major clades were formed. (i) The clade containing filamentous heterocystous cyanobacteria was divided into three discrete groups of Anabaena/Aphanizomenon, Anabaena/Cylindrospermum/ Nodularia/Nostoc and Calothrix strains. The three other clades contained (ii) filamentous non-heterocystous Planktothrix, (iii) unicellular non-heterocystous Microcystis and (iv) Synechococcus strains.

Anabaena↗

PubMed2001

Restless legs syndrome: a clinical study of 55 patients.

BACKGROUND: Restless legs syndrome (RLS) is a common sleep disorder. In 1995, clinical criteria for the diagnosis of RLS were defined. OBJECTIVE: To describe the clinical spectrum in a series of unselected RLS patients meeting the new diagnostic criteria. METHODS: We prospectively assessed by questionnaire and clinical assessment the characteristics of 55 consecutive RLS patients (35 women, 20 men; mean age = 62 +/- 16 years). RESULTS: In 27% of the patients, RLS started before the age of 20 years (early-onset RLS). Sensory disturbances were painful in 56% of patients and felt in legs (98%), arms (35%), and 'internally' (45%). Motor disturbances included 'dyskinesias while awake' (36%). Insomnia (58%) was commoner than hypersomnia (24%). In 67% of the patients, no etiology of RLS was found (idiopathic RLS). Early-onset RLS was more commonly familial (p = 0.01) and associated with 'growing pains' (p = 0.005) than late-onset RLS. Patients with RLS and hypersomnia were younger (p = 0.01) and less commonly had painful sensations (p = 0.04) than patients with RLS and insomnia. Patients with idiopathic RLS were younger (p = 0.004), and less commonly had insomnia (p = 0.01) than patients with symptomatic RLS. CONCLUSIONS: RLS is a clinically pleomorphic syndrome, reflecting the contribution of multiple genetic and acquired factors in the pathogenesis of RLS.

Adult↗

PubMed2000

[Prevalence of sleep disorders in an employed Swiss population: results of a questionnaire survey].

BACKGROUND: The aim of the study was to demonstrate the variety of sleep disorders occurring in a working population in Switzerland and to estimate the prevalence of the main sleep disorders in this Swiss cohort. We also intended to demonstrate that with just a few systematic questions a straightforward diagnostic workup is possible in general practice. METHODS: A questionnaire was sent to all 1473 clerks of the Berne main post office. The questions allowed a choice between "yes" or "no", or often (= +3), occasionally (= +2), rarely (= +) and never (= 0). Daytime sleepiness was assessed by the Epworth Sleepiness Scale. RESULTS: 668 questionnaires (45%) were available for analysis. Daytime sleepiness, assessed by an Epworth score > or = 10, was found in 13% of the respondents. Short sleep (< 7 h sleep) was reported in 47%, and long sleep (> 9 h sleep) in 5% of this population. Specific questions clearly suggested obstructive sleep apnoea in 6%, restless-legs syndrome in 4%, disorders of initiating and maintaining sleep in 19% and narcolepsy in 0.5% of respondents. CONCLUSION: Chronic sleep insufficiency and sleep complaints appear to be frequent in this relatively young Swiss working population. The questionnaire-based estimated prevalence of the main sleep disorders is comparable to previously published international data.

Adult↗

PubMed2000

Sleepiness-related accidents in sleep apnea patients.

The frequency of motor vehicle and working accidents was analyzed by means of a strictly anonymous questionnaire in 156 patients with sleep apnea syndrome (SAS) and in 160 age-gender matched controls. In the SAS group 12.4% of all drivers had motor vehicle accidents as compared to 2.9% in the control group (p<0.005). The motor vehicle accident rate was 13.0 per million km in patients with more severe SAS (AHI > 34/h, n=78) as compared to 1.1 in patients with milder SAS (AHI 10-34/h, n=78) (p<0.05), and 0.78 in control group (p<0.005), respectively. The accident rates in both patients and the control group were also greater than the rate of 0.02 "accidents due to sleepiness" per one million km in the Swiss driving population as reported by official statistics. During treatment with nasal continuous airway pressure (nCPAP) in 85 SAS patients, the motor vehicle accident rate dropped from 10.6 to 2.7 per million km (p<0.05). We conclude that patients with moderate to severe SAS have an up to fifteen-fold risk increase of motor vehicle accidents that constitutes a serious and often underestimated hazard on the roads, which can be reduced by adequate treatment.

Accidents, Traffic↗

PubMed2000

Prognostic relevance of Masaoka and Müller-Hermelink classification in patients with thymic tumors.

BACKGROUND: To compare the prognostic relevance of Masaoka and Müller-Hermelink classifications. METHODS: We treated 71 patients with thymic tumors at our institution between 1980 and 1997. Complete follow-up was achieved in 69 patients (97%) with a mean follow up-time of 8.3 years (range, 9 months to 17 years). RESULTS: Masaoka stage I was found in 31 patients (44.9%), stage II in 17 (24.6%), stage III in 19 (27.6%), and stage IV in 2 (2.9%). The 10-year overall survival rate was 83.5% for stage I, 100% for stage IIa, 58% for stage IIb, 44% for stage III, and 0% for stage IV. The disease-free survival rates were 100%, 70%, 40%, 38%, and 0%, respectively. Histologic classification according to Müller-Hermelink found medullary tumors in 7 patients (10.1%), mixed in 18 (26.1%), organoid in 14 (20.3%), cortical in 11 (15.9%), well-differentiated thymic carcinoma in 14 (20.3%), and endocrine carcinoma in 5 (7.3%), with 10-year overall survival rates of 100%, 75%, 92%, 87.5%, 30%, and 0%, respectively, and 10-year disease-free survival rates of 100%, 100%, 77%, 75%, 37%, and 0%, respectively. Medullary, mixed, and well-differentiated organoid tumors were correlated with stage I and II, and well-differentiated thymic carcinoma and endocrine carcinoma with stage III and IV (p < 0.001). Multivariate analysis showed age, gender, myasthenia gravis, and postoperative adjuvant therapy not to be significant predictors of overall and disease-free survival after complete resection, whereas the Müller-Hermelink and Masaoka classifications were independent significant predictors for overall (p < 0.05) and disease-free survival (p < 0.004; p < 0.0001). CONCLUSIONS: The consideration of staging and histology in thymic tumors has the potential to improve recurrence prediction and patient selection for combined treatment modalities.

Adult↗

PubMed2000

Functional assessment of chest wall integrity after methylmethacrylate reconstruction.

BACKGROUND: All patients with extensive resection of the anterolateral chest wall and the sternum followed by reconstruction with methylmethacrylate substitutes were assessed prospectively 6 months after the operation to delineate chest wall integrity with pulmonary function and cine-magnetic resonance imaging. METHODS: Twenty-six patients underwent chest wall reconstruction by use of methylmethacrylate between 1994 and 1998 due to primary tumors in 35%, metastases in 27%, T3 lung cancer in 19%, and debridement for radionecrosis and osteomyelitis in 19% of patients. Three to eight ribs were resected and additional sternum resection was performed in 39% of patients. RESULTS: There was no 30-day mortality. All patients were extubated after the operation without need for reintubation. Prosthesis dislocation occurred in 1 patient and infection in 2 patients during follow-up. Nineteen patients (73%) suffered no restrictions of daily activities. Clinical examination revealed normal shoulder girdle function in 77% of patients. There was no significant difference between preoperative and postoperative FEV1 (forced expiratory volume in 1 second) measurements in patients with lobectomy or wedge resections. Cinemagnetic resonance imaging revealed concordant chest wall movements during respiration in 92% of patients without paradoxical movements or implant dislocations being observed. CONCLUSIONS: Large defects of the anterolateral chest wall and sternum can be reconstructed efficiently with methylmethacrylate substitutes with minimal morbidity and excellent cosmetic and functional outcome.

Adult↗

PubMed2000

[Hypersomnia--etiology, clinic, diagnosis and therapy of excessive sleepiness].

Hypersomnia (excessive sleepiness) refers to an increased sleep propensity with a subjective craving for sleep, involuntary naps and "sleep attacks" during the day and/or prolonged nighttime sleep with sleep drunkeness. Excessive sleepiness should be separated from fatigue and lack of energy associated with a variety of medical and psychiatric diseases. Hypersomnia is reported by 2-5% of the adult population and can lead to poor work, accidents and neuropsychiatric disturbances. Sleep apnea syndrome (SAS), narcolepsy, chronic sleep deprivation (insufficiency), and restless legs/periodic limb movements in sleep syndrome (RLS/PLMS) represent the most common causes of hypersomnia. The diagnosis of these conditions can often be suspected on clinical grounds. However, an overnight polysomnography and a multiple sleep latency test are often additionally required for definite diagnosis. Treatment options include nasal CPAP for SAS, stimulants for narcolepsy, sleep prolongation for sleep insufficiency, and dopaminergic agents for RLS/PLMS.

Adult↗

PubMed2000

[Effectiveness of nasal CPAP-treatment (continuous positive airway pressure)].

Nasal continuous positive airway pressure (n-CPAP) is an effective treatment for the obstructive sleep apnea syndrome (OSAS). It is currently regarded as the first line therapy for OSAS. The principal indication for n-CPAP treatment is daytime sleepiness. Nasal-CPAP improves daytime sleepiness dramatically in severe cases and the effect is objectively measurable with the multiple sleep latency test (MSLT). It is noteworthy that n-CPAP also improves symptoms, subjective daytime sleepiness, cognitive function, IQ, mood, quality of life and driving ability already in patients with mild sleep apnea with an apnea/hypopneaindex (AHI) between 5 and 15 per hour of sleep during overnight polysomnography. Although not yet 100% robust, there is clear evidence that patients with OSAS have an increased frequency of systemic hypertension. Some early and imperfect studies suggest that CPAP reduces cardiovascular and cerebrovascular outcomes; however unequivocal evidence that n-CPAP reduces mortality is still awaited. There is now good evidence that treatment with n-CPAP reduces the two- to sevenfold increased risk of road accidents of untreated patients with OSAS. In summary, there exists abundant evidence today that n-CPAP is an efficient therapy for symptomatic patients with the obstructive sleep apnea syndrome. A trial with n-CPAP is therefore justified in all symptomatic patients. Based on the large number of randomized controlled trials of n-CPAP a therapeutic trial is indicated even in only mildly symptomatic patients with OSAS. Nasal-CPAP use and outcomes of therapy can be improved by provision of an intensive CPAP-education and support program.

Accidents, Traffic↗

PubMed2000

[Nocturnal measurements of intraocular pressure in patients with normal-tension glaucoma and sleep apnea syndrome].

BACKGROUND: About half of all normal-tension glaucoma patients and about one third of all primary open-angle glaucoma patients have sleep apnea syndrome. If sleep apnea syndrome causes some cases of glaucoma, the optic nerve damage could result from repetitive nocturnal hypoxias or from repetitive intraocular pressure elevations at the end of the apneas. In this study, we determined the intraocular pressure at the end of long apneas. PATIENTS AND METHODS: In three patients having sleep apnea syndrome and normal-tension glaucoma we recorded in a sleep laboratory during at least six hours of sleep the respiration (oxymetry, nasal and oral air flow, and inductive plethysmography). The intraocular pressure was measured with a pneumatonometer at predetermined times and compared to the values measured at the end of prolonged apneas. RESULTS: The intraocular pressure during normal respiration was in the first patient 19.5 +/- 1.0 mm Hg OD and 19.3 +/- 1.7 mm Hg OS, in the second patient 25.0 +/- 4.2 respectively 25.5 +/- 4.9 mm Hg and in the third one 22 +/- 1.0 respectively 21.3 +/- 1.3 mm Hg. At the end of prolonged apneas the intraocular pressure was in the first patient 19.0 +/- 0.0 mm Hg OD and 19.5 +/- 0.7 mm Hg OS, in the second patient 26.5 +/- 0.6 and 26.8 +/- 0.1 mm Hg and in the third one 20.0 +/- 0.0 respectively 21.0 +/- 0.0 mm Hg. The difference between intraocular pressures during normal respiration and at the end of prolonged apneas was not significant (p > 0.1 for each comparison, paired t-test). CONCLUSIONS: We did not find an increase of intraocular pressure at the end of prolonged apneas compared to periods of normal respiration in patients with sleep apnea syndrome and normal-tension glaucoma. If sleep apnea syndrome causes some cases of glaucoma, it seems more probable that the the optic nerve is damaged by the repetitive hypoxias. Alternatively, an unknown factor might induce both, sleep apnea syndrome and normal-tension glaucoma.

Aged↗

PubMed1999

[Safety profile of zolpidem: two studies of 3805 patients by Swiss practitioners].

Evaluation and treatment of insomnia are frequent procedures in the physician's everyday practice, since many patients seek medical treatment for this condition. Knowledge of pharmacological therapeutical alternatives is therefore decisive, in order to identify the most efficaceous and safe therapy for the patient among the available hypnotics. The short-acting hypnotic zolpidem has been investigated in Switzerland in two multicenter safety studies in ambulatory practice. In the first study 8.9% (n = 125 of 1,972 treated patients), and in the second 7.2% of the patients (n = 175 of 1,833 treated patients) reported an adverse event. The most frequent events were related to the central nervous system (CNS) (somnolence, headache, confusion, vertigo); gastrointestinal and cutaneous symptoms were the most frequent non CNS-dependent effects. New, unknown or serious adverse events were not found and no specific risk factor or population at risk was identified. The safety profile of zolpidem is consistent with its known pharmacological properties, the results of previous clinical trials and the international experience obtained in large patients groups.

Adolescent↗

PubMed1999

[Parapneumonic pleural effusion, pleural empyema: medical and surgical aspects].

The following are essential for prophylaxis and treatment of empyema: antibiotic therapy for pneumonia, based on susceptibility results; early detection of parapneumonic effusions (decubitus radiograph, sonography); immediate diagnostic thoracocentesis if a parapneumonic effusion is large, increasing despite antibiotic therapy, if it is associated with clinical deterioration or if empyema is suspected; assessment of the stage of parapneumonic effusion or empyema (clinical signs, sonography, CT, laboratory parameters); immediate therapeutic thoracocentesis of frank empyema, in loculated empyema fibrinolytic agents may be used; early surgical intervention if conservative management fails; complete thoracoscopic decortication, if necessary open thoracotomy to assure complete reexpansion of the lung.

Empyema, Pleural↗

PubMed1999

Gastrin-releasing peptide receptors in non-neoplastic and neoplastic human breast.

The regulatory peptide gastrin-releasing peptide (GRP) may play a role in human cancer as a stimulatory growth factor. To understand the potential role of GRP in human breast cancer, we have evaluated GRP receptor expression in human non-neoplastic and neoplastic breast tissues and in axillary lymph node metastases, using in vitro receptor autoradiography on tissue sections with [(125)I]Tyr(4)-bombesin and with [(125)I]D-Tyr(6), beta Ala(11), Phe(13), Nle(14)-bombesin(6-14) as radioligands. GRP receptors were detected, often in high density, in neoplastic epithelial mammary cells in 29 of 46 invasive ductal carcinomas, in 11 of 17 ductal carcinomas in situ, in 1 of 4 invasive lobular carcinomas, in 1 of 2 lobular carcinomas in situ, and in 1 mucinous and 1 tubular carcinoma. A heterogeneous GRP receptor distribution was found in the neoplastic tissue samples in 32 of 52 cases with invasive carcinoma and 12 of 19 cases with carcinoma in situ. The lymph node metastases (n = 33) from those primary carcinomas expressing GRP receptors were all positive, whereas surrounding lymphoreticular tissue was negative. GRP receptors were also present in high density but with heterogeneous distribution in ducts and lobules from all available breast tissue samples (n = 23). All of the receptors corresponded to the GRP receptor subtype of bombesin receptors, having high affinity for GRP and bombesin and lower affinity for neuromedin B. All tissues expressing GRP receptors were identified similarly with both radioligands. These data describe not only a high percentage of GRP receptor-positive neoplastic breast tissues but also for the first time a ubiquitous GRP receptor expression in nonneoplastic human breast tissue. Apart from suggesting a role of GRP in breast physiology, these data represent the molecular basis for potential clinical applications of GRP analogs such as GRP receptor scintigraphy, radiotherapy, or chemotherapy.

Adult↗

PubMed1999

Eyelid, conjunctival, and corneal findings in sleep apnea syndrome.

OBJECTIVE: To determine the prevalence of eyelid, conjunctival, and corneal findings in patients with sleep apnea syndrome (SAS). DESIGN: Case series. PARTICIPANTS: Seventy-two white patients referred for evaluation of suspected SAS. INTERVENTION: Complete examination of eyelids, conjunctiva, and cornea, including videokeratography. MAIN OUTCOME MEASURES: Spearman rank correlations were determined between the respiratory disturbance index (RDI) during night sleep, a value used to diagnose and grade SAS, and tear film break-up time, eyelid distraction distance, presence or absence of ocular irritation symptoms, blepharoptosis, floppy eyelids, lacrimal gland prolapse, keratoconus, and endothelial dystrophy. Each correlation was controlled for age and body mass index. RESULTS: According to the RDI, 44 (61 %) of the 72 patients had SAS. The RDI correlated positively with the eyelid distraction distance (P = 0.05), presence or absence of floppy eyelids (P = 0.01), and lacrimal gland prolapse (P = 0.01), and correlated negatively with tear film break-up time (P = 0.02). None of our patients with floppy eyelids had corneal abnormalities. One patient with SAS had bilateral keratoconus; another had bilateral Fuch endothelial dystrophy. CONCLUSIONS: Sleep apnea syndrome was significantly associated with reduced tear film break-up time, floppy eyelids, and lacrimal gland prolapse. However, ocular irritation symptoms and corneal involvement were rare among patients with SAS. These findings do not confirm previous studies that reported a high prevalence of corneal involvement in floppy eyelid syndrome.

Adult↗

PubMed1999

Morbidity and validity of the hemiclamshell approach for thoracic surgery.

OBJECTIVE: This is a prospective study to evaluate the indications and outcome of the hemiclamshell incision (longitudinal partial sternotomy combined with an antero-lateral thoracotomy) as used for a consecutive series of patients requiring surgery for various thoracic pathologies not ideally approached by postero-lateral thoracotomy, sternotomy or thoracoscopy. METHODS: All patients with a hemiclamshell incision performed between 1994 and 1998 were prospectively analyzed regarding indications, postoperative morbidity and outcome (clinical examination and pulmonary function testing) in order to validate this incision for thoracic surgery. RESULTS: 25 patients (15 men, 10 women) with an age ranging from 16 to 73 years (mean 43 years) underwent a hemiclamshell incision. The indications for the hemiclamshell approach were (1) chest trauma with massive hemorrhage requiring urgent access to the mediastinum and the ipsilateral pleural space (40%), (2) tumors of the anterior cervico-thoracic junction with suspicion of vascular involvement (28%) and (3) lesions involving both one chest cavity and the mediastinum (32%). The 30-day mortality was 8%. One patient suffered a sternal wound infection, mediastinitis and pleural empyema after a gun shot wound, whereas wound healing was uneventful in all other patients. Analgesic requirements for postoperative pain relief were not increased as compared to those following a standard thoracotomy. At 3 months normal sensitivity of the entire chest wall and intact shoulder girdle function was noted in 90% of the patients. Pulmonary function testing showed no restriction due to the hemiclamshell incision. CONCLUSIONS: The hemiclamshell incision is a useful approach in selected patients and does not cause more morbidity or long-term sequelae than a standard thoracotomy.

Adolescent↗

PubMed1999

Bronchogenic cyst of the left lower lobe associated with severe hemoptysis.

Bronchogenic cysts result from congenital disorders, are often asymptomatic at diagnosis, but complications are not uncommon. We report the case of a 19-year-old woman with severe hemoptysis. This rare presentation of an intrapulmonary bronchogenic cyst should be considered as differential diagnosis in patients with cavernous lesion of a lobe. Surgery was performed as a diagnostic and therapeutic measure.

Adult↗

PubMed1999

Left recurrent laryngeal nerve palsy associated with silicosis.

Left recurrent laryngeal nerve palsy usually results from invasion or compression of the nerve caused by diseases localized within the aortopulmonary window. This study reports the case of a 76-yr-old male with vocal cord paralysis due to lymph node involvement by silicosis. This rare entity was identified by video-mediastinoscopy, which revealed a granulomatous and fibrosed recurrent lymph node encasing the nerve. The nerve was dissected and released from scar tissues. Progressive clinical improvement was observed followed by total and durable recovery of the voice after 15 weeks follow-up.

Aged↗

PubMed1999

Ambulatory nocturnal oximetry and sleep questionnaire-based findings in 38 patients with end-stage renal disease.

BACKGROUND: Patients with end-stage renal diseases (ESRD) have an increased risk of sleep-disordered breathing. With regard to this disorder, controversy persists about prevalence, cost-effective assessment and socio-economical relevance. METHODS: Therefore, we performed, for the first time, overnight ambulatory oximetry in combination with a sleep questionnaire in 38 unselected patients with ESRD and 37 healthy controls. An oxygen desaturation index (ODI) >15, defined as >15 falls in oxygen saturation of > or =4% per h, was observed more frequently in ESRD patients than in healthy controls (47 vs. 3%, P<0.001). RESULTS: In general, the results derived from the assessment of the Epworth Sleepiness Scale (ESS) as well as those from the visual analogue scale (VAS) did not reflect the ODI values of the respective patient population. Interestingly, 88% of ESRD patients with the questionnaire finding 'excessively loud snoring' had an ODI of >15 as compared with 13% without this complaint (P<0.05). Furthermore, 77% of ESRD patients with a systolic blood pressure >140 mm Hg and a body mass index (BMI) >25, had an ODI of >15. The percentage of ESRD patients with a professional activity was higher in the absence of sleep-disordered breathing (63 vs. 21%, P<0.05). CONCLUSION: 'Excessively loud snoring' and a BMI >25 combined with hypertension are risk factors for sleep-disordered breathing in ESRD patients. Nocturnal oxygen desaturations are assessed efficiently by ambulatory oximetry and correlate with relevant biological and socio-economical parameters in ESRD patients.

Adult↗

PubMed1998

Arousal responses to inspiratory resistive loading during REM and non-REM sleep in normal men after short-term fragmentation/deprivation.

The arousal response to inspiratory resistive loading in normal men is known to be high during REM sleep compared to non-REM sleep. We investigated whether we could observe the same pattern, i.e. brisk arousal from REM sleep compared to non-REM sleep, in normal subjects who had undergone short-term sleep fragmentation/deprivation prior to the investigation. The arousal response to the repeated application of an external inspiratory resistance of 25 cm H2O/l/s was determined during REM and non-REM sleep in 10 healthy men after a single night with 4 hours of acoustically fragmented sleep. The percentage of arousals to non-arousals occurring within 2 minutes of the load application was significantly higher during REM sleep than during either of the non-REM sleep stages 2 and 3/4 and decreased significantly from stage REM to stage 2 and from stage 2 to stage 3/4. The mean time to arousal in REM was significantly shorter than in non-REM stage 3/4. The duration of sleep (comparing the results of the first with the second half of the sleep period time) did not modify the arousal response in stages 2 and 3/4. Despite short-term sleep fragmentation/deprivation the night before the study, the arousal response to external inspiratory resistive loading was brisker during REM than non-REM sleep in the healthy subjects studied. The responses were of the same magnitude as those induced in prior studies without pretest sleep disturbance. This is different from what is seen in patients with sleep apnea, where breathing disorders are worst during REM sleep and sleep fragmentation/deprivation leads to rapid deterioration of arousal responses to the spontaneously occurring airway occlusions.

Acoustic Stimulation↗