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Lazzareschi I, Curatola A, Massimi L, Rendeli C, Rollo E, Scala I, Della Marca G, Brunetti V. Sleep-disordered breathing in patients with Chiari malformation type II: a case-control study and review of the literature. J Clin Sleep Med 2022; 18:2143-2154. [PMID: 35645039 PMCID: PMC9435333 DOI: 10.5664/jcsm.10062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 04/09/2022] [Accepted: 04/12/2022] [Indexed: 11/13/2022]
Abstract
STUDY OBJECTIVES The main aim was to evaluate the prevalence of sleep-disordered breathing (SDB) in patients with Chiari II malformation (CM-II). The secondary objectives were to evaluate the association between SDB, morphological abnormalities, and neurological symptoms and to review the literature on patients with SDB and CM-II. METHODS The study has a cross-sectional, case-control design. Patients with CM-II (patients) were compared to control patients referred for clinical polysomnography in the Sleep Medicine Unit, matched for age and sex. All patients underwent brain and spinal cord magnetic resonance imaging, and polysomnography was conducted for all participants. A review of the literature about SDB in patients with CM-II was performed. RESULTS Forty patients were included (20 patients vs 20 control patients). SDB was identified in 45% of patients, a significantly higher prevalence compared to control patients. Three patients presented with purely obstructive SDB, 3 patients with purely central SDB, and 3 patients with both obstructive and central SDB. Compared with control patients, patients with CM-II showed a higher oxygen desaturation index (median: CM-II, 3.7; interquartile range, 1.6-19.5; control patients: 1.1; interquartile range, 0.3-3.2) and obstructive apnea-hypopnea index (median: CM-II, 1.5; interquartile range, 0.5-5.1; control patients, 0.1; interquartile range, 0.0-0.7). A logistic regression showed that the risk of developing SDB in patients affected by CM-II was 14.7 times higher than in the control population. CONCLUSIONS Our study and literature review showed a high prevalence of SDB in patients with CM-II. These patients are often asymptomatic at diagnosis, suggesting that PSG should be routinely provided in this population. CITATION Lazzareschi I, Curatola A, Massimi L, et al. Sleep-disordered breathing in patients with Chiari malformation type II: a case-control study and review of the literature. J Clin Sleep Med. 2022;18(9):2143-2154.
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Affiliation(s)
- Ilaria Lazzareschi
- Department of Pediatrics, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Antonietta Curatola
- Department of Pediatrics, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Luca Massimi
- Department of Pediatric Neurosurgery, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Claudia Rendeli
- Department of Pediatrics, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Eleonora Rollo
- Dipartimento di Neuroscienze, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Irene Scala
- Dipartimento di Neuroscienze, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Giacomo Della Marca
- Dipartimento di Scienze dell’Invecchiamento, Neurologiche, Ortopediche e della Testa-Collo, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy
| | - Valerio Brunetti
- Dipartimento di Scienze dell’Invecchiamento, Neurologiche, Ortopediche e della Testa-Collo, Fondazione Policlinico Universitario Agostino Gemelli, IRCCS, Rome, Italy
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Saddi V, Thambipillay G, Pithers S, Moody M, Martin B, Blecher G, Teng A. Average volume-assured pressure support vs conventional bilevel pressure support in pediatric nocturnal hypoventilation: a case series. J Clin Sleep Med 2021; 17:925-930. [PMID: 33393900 DOI: 10.5664/jcsm.9084] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
STUDY OBJECTIVES Average volume-assured pressure support (AVAPS) is a modality of noninvasive ventilation that provides a targeted tidal volume by automatically adjusting the inspiratory pressure support within a set range. Pediatric studies evaluating the efficacy of AVAPS in treating nocturnal hypoventilation are confined to case reports. The aim of this study was to compare AVAPS to conventional bilevel positive airway pressure (BPAP) support in improving hypercarbia in a cohort of pediatric patients with nocturnal hypoventilation. METHODS Retrospective review of patient records at an established tertiary pediatric sleep laboratory over a 6-year period. Ventilatory and sleep study parameters from AVAPS and conventional BPAP titration studies were compared. AVAPS was used only if hypoventilation was not controlled using conventional BPAP. Inspiratory pressures, tidal volumes, and adherence were downloaded on final titrated ventilatory settings. Comparisons were made using paired t test. RESULTS A total of 19 patients (11 boys, 8 girls; median age 10.5 years, range 1 to 20 years) were identified. Diagnoses included neuromuscular disease (n = 9), obstructive hypoventilation (n = 5), parenchymal lung disease (n = 4), and congenital central hypoventilation syndrome (n = 2). AVAPS demonstrated significant improvement in peak (P = .009) and mean (P = .001). Transcutaneous CO₂ parameters compared to conventional bilevel. Oxygenation on AVAPS showed positive trend but did not reach statistical significance. AVAPS delivered higher tidal volumes (P = .04) using similar pressures. There was no statistically significant difference in obstructive apnea-hypopnea index, respiratory arousal index, sleep efficiency, and adherence between AVAPS and conventional BPAP. CONCLUSIONS AVAPS was an effective alternative to conventional BPAP in improving hypercarbia in our selective cohort of pediatric patients. Prospective, longitudinal studies are needed to evaluate the benefits of AVAPS feature in the pediatric population.
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Affiliation(s)
- Vishal Saddi
- Department of Sleep Medicine, Sydney Children's Hospital, Randwick, New South Wales, Australia.,Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia
| | - Ganesh Thambipillay
- Department of Sleep Medicine, Sydney Children's Hospital, Randwick, New South Wales, Australia.,Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia
| | - Sonia Pithers
- Department of Sleep Medicine, Sydney Children's Hospital, Randwick, New South Wales, Australia
| | - Miles Moody
- Department of Sleep Medicine, Sydney Children's Hospital, Randwick, New South Wales, Australia
| | - Bradley Martin
- Department of Sleep Medicine, Sydney Children's Hospital, Randwick, New South Wales, Australia.,Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia
| | - Gregory Blecher
- Department of Sleep Medicine, Sydney Children's Hospital, Randwick, New South Wales, Australia.,Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia
| | - Arthur Teng
- Department of Sleep Medicine, Sydney Children's Hospital, Randwick, New South Wales, Australia.,Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia
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Pavšič K, Pretnar-Oblak J, Bajrović FF, Dolenc-Grošelj L. Breathing patterns in relation to sleep stages in acute unilateral lateral medullary infarction: An exploratory study. Respir Physiol Neurobiol 2021; 285:103592. [DOI: 10.1016/j.resp.2020.103592] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 11/17/2020] [Accepted: 11/26/2020] [Indexed: 12/16/2022]
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Landry SA, Andara C, Terrill PI, Joosten SA, Leong P, Mann DL, Sands SA, Hamilton GS, Edwards BA. Ventilatory control sensitivity in patients with obstructive sleep apnea is sleep stage dependent. Sleep 2019; 41:4944421. [PMID: 29741725 DOI: 10.1093/sleep/zsy040] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Indexed: 11/14/2022] Open
Abstract
Study Objectives The severity of obstructive sleep apnea (OSA) is known to vary according to sleep stage; however, the pathophysiology responsible for this robust observation is incompletely understood. The objective of the present work was to examine how ventilatory control system sensitivity (i.e. loop gain) varies during sleep in patients with OSA. Methods Loop gain was estimated using signals collected from standard diagnostic polysomnographic recordings performed in 44 patients with OSA. Loop gain measurements associated with nonrapid eye movement (NREM) stage 2 (N2), stage 3 (N3), and REM sleep were calculated and compared. The sleep period was also split into three equal duration tertiles to investigate how loop gain changes over the course of sleep. Results Loop gain was significantly lower (i.e. ventilatory control more stable) in REM (Mean ± SEM: 0.51 ± 0.04) compared with N2 sleep (0.63 ± 0.04; p = 0.001). Differences in loop gain between REM and N3 (p = 0.095), and N2 and N3 (p = 0.247) sleep were not significant. Furthermore, N2 loop gain was significantly lower in the first third (0.57 ± 0.03) of the sleep period compared with later second (0.64 ± 0.03, p = 0.012) and third (0.64 ± 0.03, p = 0.015) tertiles. REM loop gain also tended to increase across the night; however, this trend was not statistically significant [F(2, 12) = 3.49, p = 0.09]. Conclusions These data suggest that loop gain varies between REM and NREM sleep and modestly increases over the course of sleep. Lower loop gain in REM is unlikely to contribute to the worsened OSA severity typically observed in REM sleep, but may explain the reduced propensity for central sleep apnea in this sleep stage.
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Affiliation(s)
- Shane A Landry
- Sleep and Circadian Medicine Laboratory, Department of Physiology, Monash University, Melbourne, VIC, Australia.,School of Psychological Sciences and Monash Institute of Cognitive and Clinical Neurosciences, Monash University, Melbourne, VIC, Australia
| | - Christopher Andara
- Sleep and Circadian Medicine Laboratory, Department of Physiology, Monash University, Melbourne, VIC, Australia.,School of Psychological Sciences and Monash Institute of Cognitive and Clinical Neurosciences, Monash University, Melbourne, VIC, Australia
| | - Philip I Terrill
- School of Information Technology and Electrical Engineering, The University of Queensland, Brisbane, Australia
| | - Simon A Joosten
- Monash Lung and Sleep, Monash Medical Centre, Clayton, VIC, Australia.,School of Clinical Sciences, Monash University, Melbourne, VIC, Australia.,Monash Partners - Epworth, Victoria, Australia
| | - Paul Leong
- Monash Lung and Sleep, Monash Medical Centre, Clayton, VIC, Australia
| | - Dwayne L Mann
- School of Information Technology and Electrical Engineering, The University of Queensland, Brisbane, Australia
| | - Scott A Sands
- Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA.,The Alfred and Monash University, Melbourne, VIC, Australia
| | - Garun S Hamilton
- Monash Lung and Sleep, Monash Medical Centre, Clayton, VIC, Australia.,School of Clinical Sciences, Monash University, Melbourne, VIC, Australia.,Monash Partners - Epworth, Victoria, Australia
| | - Bradley A Edwards
- Sleep and Circadian Medicine Laboratory, Department of Physiology, Monash University, Melbourne, VIC, Australia.,School of Psychological Sciences and Monash Institute of Cognitive and Clinical Neurosciences, Monash University, Melbourne, VIC, Australia
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Lee KZ. Impact of cervical spinal cord contusion on the breathing pattern across the sleep-wake cycle in the rat. J Appl Physiol (1985) 2019; 126:111-123. [DOI: 10.1152/japplphysiol.00853.2018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The present study was designed to investigate breathing patterns across the sleep-wake state following a high cervical spinal injury in rats. The breathing patterns (e.g., respiratory frequency, tidal volume, and minute ventilation), neck electromyogram, and electroencephalography of unanesthetized adult male rats were measured at the acute (i.e., 1 day), subchronic (i.e., 2 wk), and/or chronic (i.e., 6 wk) injured stages after unilateral contusion of the second cervical spinal cord. Cervical spinal cord injury caused a long-term reduction in the tidal volume but did not influence the sleep-wake cycle duration. The minute ventilation during sleep was usually lower than that during the wake period in uninjured animals due to a decrease in respiratory frequency. However, this sleep-induced reduction in respiratory frequency was not observed in contused animals at the acute injured stage. By contrast, the tidal volume was significantly lower during sleep in contused animals but not uninjured animals from the acute to the chronic injured stage. Moreover, the frequency of sigh and postsigh apnea was elevated in acutely contused animals. These results indicated that high cervical spinal contusion is associated with exacerbated sleep-induced attenuation of the tidal volume and higher occurrence of sleep apnea, which may be detrimental to respiratory functional recovery after cervical spinal cord injury. NEW & NOTEWORTHY Cervical spinal injury is usually associated with sleep-disordered breathing. The present study investigated breathing patterns across sleep-wake state following cervical spinal injury in the rat. Unilateral cervical spinal contusion significantly impacted sleep-induced alteration of breathing patterns, showing a blunted frequency response and exacerbated attenuated tidal volume and occurrence of sleep apnea. The result enables us to investigate effects of cervical spinal injury on the pathogenesis of sleep-disordered breathing and evaluate potential therapies to improve respiration.
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Affiliation(s)
- Kun-Ze Lee
- Department of Biological Sciences, National Sun Yat-sen University, Kaohsiung, Taiwan
- Center for Neuroscience, National Sun Yat-sen University, Kaohsiung, Taiwan
- Institute of Medical Science and Technology, National Sun Yat-sen University, Kaohsiung, Taiwan
- Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, Kaohsiung, Taiwan
- Doctoral Degree Program in Marine Biotechnology, National Sun Yat-sen University and Academia Sinica, Taiwan
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Rodrigues LTC, da Silva EN, Horta-Júnior JDAC, Gargaglioni LH, Dias MB. Glutamate metabotropic receptors in the lateral hypothalamus/perifornical area reduce the CO 2 chemoreflex. Respir Physiol Neurobiol 2018; 260:122-130. [PMID: 30471436 DOI: 10.1016/j.resp.2018.11.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 10/27/2018] [Accepted: 11/20/2018] [Indexed: 11/26/2022]
Abstract
It has been shown that the lateral hypothalamus/perifornical area (LH/PFA) exerts an important role on arousal-state variations of the central chemoreflex, but the mechanisms that underlie LH/PFA chemoreception are poorly understood. Here we asked whether glutamate inputs on metabotropic receptors in the LH/PFA modulate the hypercapnic ventilatory response. We studied the effects of microinjection of a glutamate metabotropic receptor (mGluR) antagonist ((+)-α-Methyl-4-carboxyphenylglycine; MCPG; 100 mM) and a selective Group II/III mGluR antagonist ((2S)-2-Amino-2-[(1S,2S)-2-carboxycycloprop-1-yl]-3-(xanth-9-yl) propanoic acid; LY341495; 5 mM) into the LH/PFA of conscious rats on ventilation in room air and in 7% CO2, during wakefulness and sleep, in the dark and light periods of the diurnal cycle. Microinjection of MCPG and LY341495 increased the hypercapnic ventilatory response in both the light and the dark period during wakefulness, but not during sleep, (p < 0.001). Our data suggest that glutamate, acting on Group II/III metabotropic receptors in the LH/PFA, exerts an inhibitory modulation of the hypercapnic ventilatory response in awake rats.
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Affiliation(s)
| | - Eliandra Nunes da Silva
- Department of Physiology, Institute of Bioscience, Sao Paulo State University-UNESP, Botucatu, SP, Brazil.
| | | | - Luciane H Gargaglioni
- Department of Animal Morphology and Physiology, Sao Paulo State University-FCAV, Jaboticabal, SP, Brazil.
| | - Mirela B Dias
- Department of Physiology, Institute of Bioscience, Sao Paulo State University-UNESP, Botucatu, SP, Brazil.
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SNORAP: A Device for the Correction of Impaired Sleep Health by Using Tactile Stimulation for Individuals with Mild and Moderate Sleep Disordered Breathing. SENSORS 2017; 17:s17092006. [PMID: 28862662 PMCID: PMC5620742 DOI: 10.3390/s17092006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 08/30/2017] [Accepted: 08/31/2017] [Indexed: 11/16/2022]
Abstract
Sleep physiology and sleep hygiene play significant roles in maintaining the daily lives of individuals given that sleep is an important physiological need to protect the functions of the human brain. Sleep disordered breathing (SDB) is an important disease that disturbs this need. Snoring and Obstructive Sleep Apnea Syndrome (OSAS) are clinical conditions that affect all body organs and systems that intermittently, repeatedly, with at least 10 s or more breathing stops that decrease throughout the night and disturb sleep integrity. The aim of this study was to produce a new device for the treatment of patients especially with position and rapid eye movement (REM)-dependent mild and moderate OSAS. For this purpose, the main components of the device (the microphone (snore sensor), the heart rate sensor, and the vibration motor, which we named SNORAP) were applied to five volunteer patients (male, mean age: 33.2, body mass index mean: 29.3). After receiving the sound in real time with the microphone, the snoring sound was detected by using the Audio Fingerprint method with a success rate of 98.9%. According to the results obtained, the severity and the number of the snoring of the patients using SNORAP were found to be significantly lower than in the experimental conditions in the apnea hypopnea index (AHI), apnea index, hypopnea index, in supine position’s AHI, and REM position’s AHI before using SNORAP (Paired Sample Test, p < 0.05). REM sleep duration and nocturnal oxygen saturation were significantly higher when compared to the group not using the SNORAP (Paired Sample Test, p < 0.05).
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Hilz MJ, Moeller S, Buechner S, Czarkowska H, Ayappa I, Axelrod FB, Rapoport DM. Obstructive Sleep-Disordered Breathing Is More Common than Central in Mild Familial Dysautonomia. J Clin Sleep Med 2016; 12:1607-1614. [PMID: 27655467 DOI: 10.5664/jcsm.6342] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Accepted: 07/19/2016] [Indexed: 01/22/2023]
Abstract
STUDY OBJECTIVES In familial dysautonomia (FD) patients, sleep-disordered breathing (SDB) might contribute to their high risk of sleep-related sudden death. Prevalence of central versus obstructive sleep apneas is controversial but may be therapeutically relevant. We, therefore, assessed sleep structure and SDB in FD-patients with no history of SDB. METHODS 11 mildly affected FD-patients (28 ± 11 years) without clinically overt SDB and 13 controls (28 ± 10 years) underwent polysomnographic recording during one night. We assessed sleep stages, obstructive and central apneas (≥ 90% air flow reduction) and hypopneas (> 30% decrease in airflow with ≥ 4% oxygen-desaturation), and determined obstructive (oAI) and central (cAI) apnea indices and the hypopnea index (HI) as count of respective apneas/hypopneas divided by sleep time. We obtained the apnea-hypopnea index (AHI4%) from the total of apneas and hypopneas divided by sleep time. We determined differences between FD-patients and controls using the U-test and within-group differences between oAIs, cAIs, and HIs using the Friedman test and Wilcoxon test. RESULTS Sleep structure was similar in FD-patients and controls. AHI4% and HI were significantly higher in patients than controls. In patients, HIs were higher than oAIs and oAIs were higher than cAIs. In controls, there was no difference between HIs, oAIs, and cAIs. Only patients had apneas and hypopneas during slow wave sleep. CONCLUSIONS In our FD-patients, obstructive apneas were more common than central apneas. These findings may be related to FD-specific pathophysiology. The potential ramifications of SDB in FD-patients suggest the utility of polysomnography to unveil SDB and initiate treatment. COMMENTARY A commentary on this article appears in this issue on page 1583.
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Affiliation(s)
- Max J Hilz
- Department of Neurology, University of Erlangen-Nürnberg, Erlangen, Germany.,Autonomic Unit, University Colloge of London, Institute of Neurology and National Hospital for Neurology and Neurosurgery, Queen Square, London, UK
| | - Sebastian Moeller
- Department of Neurology, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Susanne Buechner
- Department of Neurology, General Hospital of Bozen/Bolzano, Bozen/Bolzano, Italy
| | - Hanna Czarkowska
- Cushing Neuroscience Institute, NS-LIJ Health System, Great Neck, NY
| | - Indu Ayappa
- Division of Pulmonary, Critical Care and Sleep Medicine, New York University School of Medicine, New York, NY
| | - Felicia B Axelrod
- Dysautonomia Center, New York University Langone School of Medicine, New York, NY
| | - David M Rapoport
- Division of Pulmonary, Critical Care and Sleep Medicine, New York University School of Medicine, New York, NY
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Shteamer JW, Dedhia RC. Sedative choice in drug-induced sleep endoscopy: A neuropharmacology-based review. Laryngoscope 2016; 127:273-279. [DOI: 10.1002/lary.26132] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/23/2016] [Indexed: 11/06/2022]
Affiliation(s)
- Jack W. Shteamer
- Department of Otolaryngology; Emory University School of Medicine; Atlanta Georgia U.S.A
| | - Raj C. Dedhia
- Department of Otolaryngology; Emory University School of Medicine; Atlanta Georgia U.S.A
- Emory Sleep Center; Emory University School of Medicine; Atlanta Georgia U.S.A
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Nicolini A, Banfi P, Grecchi B, Lax A, Walterspacher S, Barlascini C, Robert D. Non-invasive ventilation in the treatment of sleep-related breathing disorders: A review and update. REVISTA PORTUGUESA DE PNEUMOLOGIA 2014; 20:324-35. [PMID: 24954545 DOI: 10.1016/j.rppneu.2014.03.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Revised: 02/08/2014] [Accepted: 03/29/2014] [Indexed: 12/14/2022] Open
Abstract
Non-invasive mechanical ventilation (NIV) was originally used in patients with acute respiratory compromises or exacerbations of chronic respiratory diseases as an alternative to intubation. Over the last thirty years NIV has been used during the night in patients with stable chronic lung diseases such as obstructive sleep apnea, the overlap syndrome (COPD and obstructive sleep apnea), neuromuscular disorders, obesity-hypoventilation syndrome and in other conditions such as sleep disorders associated with congestive heart failure. In this review we discuss the different types of NIV, the specific conditions in which they can be used as well as the indications, recommendations, and evidence supporting the efficacy of NIV.
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Affiliation(s)
- A Nicolini
- Respiratory Diseases Unit, Hospital of Sestri Levante, Italy.
| | - P Banfi
- Neuromuscular Diseases Unit, Don Gnocchi Foundation, Milan, Italy
| | - B Grecchi
- Rehabilitation Department ASL 4 Chiavarese, Italy
| | - A Lax
- Neuromuscular Diseases Unit, Don Gnocchi Foundation, Milan, Italy
| | - S Walterspacher
- Department of Pulmonology, University Hospital, Freiburg, Germany
| | | | - D Robert
- Emeritus Professor of Medicine, Claude Bernard University Lyon, France
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Ryu HU, Lee EM, Lee GH, Kim B, Lee SA. Prevalence and Predicting Factors of Complex Sleep Apnea in Patients with Obstructive Sleep Apnea Syndrome. ACTA ACUST UNITED AC 2013. [DOI: 10.13078/jksrs.13010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Fregosi RF, Ludlow CL. Activation of upper airway muscles during breathing and swallowing. J Appl Physiol (1985) 2013; 116:291-301. [PMID: 24092695 DOI: 10.1152/japplphysiol.00670.2013] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The upper airway is a complex muscular tube that is used by the respiratory and digestive systems. The upper airway is invested with several small and anatomically peculiar muscles. The muscle fiber orientations and their nervous innervation are both extremely complex, and how the activity of the muscles is initiated and adjusted during complex behaviors is poorly understood. The bulk of the evidence suggests that the entire assembly of tongue and laryngeal muscles operate together but differently during breathing and swallowing, like a ballet rather than a solo performance. Here we review the functional anatomy of the tongue and laryngeal muscles, and their neural innervation. We also consider how muscular activity is altered as respiratory drive changes, and briefly address upper airway muscle control during swallowing.
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Affiliation(s)
- Ralph F Fregosi
- Department of Physiology, University of Arizona, Tucson, Arizona
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The aging respiratory system—Pulmonary structure, function and neural control. Respir Physiol Neurobiol 2013; 187:199-210. [DOI: 10.1016/j.resp.2013.03.012] [Citation(s) in RCA: 115] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2012] [Revised: 03/25/2013] [Accepted: 03/26/2013] [Indexed: 01/31/2023]
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Hoffman M, Schulman DA. The appearance of central sleep apnea after treatment of obstructive sleep apnea. Chest 2012; 142:517-522. [PMID: 22871763 DOI: 10.1378/chest.11-2562] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Patients with a primary diagnosis of obstructive sleep apnea frequently demonstrate central sleep apnea that emerges during treatment with CPAP. Although a number of mechanisms for this finding have been hypothesized, the pathophysiology is not definitively known. Controversy exists as to whether the concomitant appearance of the two phenomena represents a distinct meaningful entity. Regardless, the coincidence of these diseases may have important clinical implications. Herein, we review the proposed mechanisms for obstructive sleep apnea complicated by central sleep apnea. Future research is needed to elucidate the relative importance and susceptibility to intervention of the various pathophysiologic mechanisms responsible for this phenomenon, and whether a treatment approach distinct from that of pure obstructive apnea is justified.
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Abstract
Respiratory activity is most fragile during sleep, in particular during paradoxical [or rapid eye movement (REM)] sleep and sleep state transitions. Rats are commonly used to study respiratory neuromodulation, but rodent sleep is characterized by a highly fragmented sleep pattern, thus making it very challenging to examine different sleep states and potential pharmacological manipulations within them. Sleep-like brain-state alternations occur in rats under urethane anesthesia and may be an effective and efficient model for sleep itself. The present study assessed state-dependent changes in breathing and respiratory muscle modulation under urethane anesthesia to determine their similarity to those occurring during natural sleep. Rats were anesthetized with urethane and respiratory airflow, as well as electromyographic activity in respiratory muscles were recorded in combination with local field potentials in neocortex and hippocampus to determine how breathing pattern and muscle activity are modulated with brain state. Measurements were made in normoxic, hypoxic, and hypercapnic conditions. Results were compared with recordings made from rats during natural sleep. Brain-state alternations under urethane anesthesia were closely correlated with changes in breathing rate and variability and with modulation of respiratory muscle tone. These changes closely mimicked those observed in natural sleep. Of great interest was that, during both REM and REM-like states, genioglossus muscle activity was strongly depressed and abdominal muscle activity showed potent expiratory modulation. We demonstrate that, in urethane-anesthetized rats, respiratory airflow and muscle activity are closely correlated with brain-state transitions and parallel those shown in natural sleep, providing a useful model to systematically study sleep-related changes in respiratory control.
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Shirahata M, Kostuk EW, Pichard LE. Carotid chemoreceptor development in mice. Respir Physiol Neurobiol 2012; 185:20-9. [PMID: 22634368 DOI: 10.1016/j.resp.2012.05.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Revised: 05/17/2012] [Accepted: 05/18/2012] [Indexed: 10/28/2022]
Abstract
Mice are the most suitable species for understanding genetic aspects of postnatal developments of the carotid body due to the availability of many inbred strains and knockout mice. Our study has shown that the carotid body grows differentially in different mouse strains, indicating the involvement of genes. However, the small size hampers investigating functional development of the carotid body. Hypoxic and/or hyperoxic ventilatory responses have been investigated in newborn mice, but these responses are indirect assessment of the carotid body function. Therefore, we need to develop techniques of measuring carotid chemoreceptor neural activity from young mice. Many studies have taken advantage of the knockout mice to understand chemoreceptor function of the carotid body, but they are not always suitable for addressing postnatal development of the carotid body due to lethality during perinatal periods. Various inbred strains with well-designed experiments will provide useful information regarding genetic mechanisms of the postnatal carotid chemoreceptor development. Also, targeted gene deletion is a critical approach.
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Affiliation(s)
- Machiko Shirahata
- Department of Environmental Health Sciences, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA.
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18
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Kamdar BB, Needham DM, Collop NA. Sleep deprivation in critical illness: its role in physical and psychological recovery. J Intensive Care Med 2012; 27:97-111. [PMID: 21220271 PMCID: PMC3299928 DOI: 10.1177/0885066610394322] [Citation(s) in RCA: 277] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Critically ill patients frequently experience poor sleep, characterized by frequent disruptions, loss of circadian rhythms, and a paucity of time spent in restorative sleep stages. Factors that are associated with sleep disruption in the intensive care unit (ICU) include patient-ventilator dysynchrony, medications, patient care interactions, and environmental noise and light. As the field of critical care increasingly focuses on patients' physical and psychological outcomes following critical illness, understanding the potential contribution of ICU-related sleep disruption on patient recovery is an important area of investigation. This review article summarizes the literature regarding sleep architecture and measurement in the critically ill, causes of ICU sleep fragmentation, and potential implications of ICU-related sleep disruption on patients' recovery from critical illness. With this background information, strategies to optimize sleep in the ICU are also discussed.
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Affiliation(s)
- Biren B. Kamdar
- Division of Pulmonary/Critical Care Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Dale M. Needham
- Division of Pulmonary/Critical Care Medicine, Johns Hopkins University, Baltimore, MD, USA
- Department of Physical Medicine and Rehabilitation, Johns Hopkins University, Baltimore, MD, USA
| | - Nancy A. Collop
- Medicine and Neurology Director, Emory Sleep Center, Emory University, MD, USA
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19
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Leskovsek M, Ahlin D, Cancer R, Hosta M, Enova D, Pusenjak N, Bunc M. Low latency breathing frequency detection and monitoring on a personal computer. J Med Eng Technol 2011; 35:322-9. [PMID: 21767133 DOI: 10.3109/03091902.2011.591481] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
We demonstrate a low latency respiratory/breathing frequency detection system that is fast (<5 ms), easy to operate, requires no batteries or external power supply and operates fully via computer-standard USB connection. Exercises in controlling ones breathing frequency, usually referred to as paced-breathing exercises, have shown positive effects in treating pulmonary diseases, cardiovascular diseases and stress/anxiety-related disorders. We developed a breathing frequency detection system which uses two pairs of microphones to detect exhalation activity, eliminate noise from the environment and stream the recording data via USB connection to a personal computer. It showed 97.1% reliability (10 subjects) when monitoring breathing activity in non-guided free breathing and 100% reliability (10 subjects) when monitoring breathing activity during interactive paced-breathing exercises. We also evaluated the breathing frequency detection systems noise elimination functionality which showed a reduction of 84.2 dB for stationary (white noise) and a reduction of 79.3 dB for non-stationary (hands clapping) noise.
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Affiliation(s)
- Matevz Leskovsek
- Faculty of Electrical Engineering, University of Ljubljana, Ljubljana, Slovenia.
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20
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Sahin-Yilmaz A, Naclerio RM. Anatomy and physiology of the upper airway. PROCEEDINGS OF THE AMERICAN THORACIC SOCIETY 2011; 8:31-39. [PMID: 21364219 DOI: 10.1016/b978-1-4160-6645-3.00101-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The nose is the major portal of air exchange between the internal and external environment. The nose participates in the vital functions of conditioning inspired air toward a temperature of 37°C and 100% relative humidity, providing local defense and filtering inhaled particulate matter and gases. It also functions in olfaction, which provides both a defense and pleasure for the individual. Understanding normal physiology provides the basis for recognizing abnormalities.
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Affiliation(s)
- Asli Sahin-Yilmaz
- Umraniye Education and Research Hospital, Department of Otolaryngology, Istanbul, Turkey
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21
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Schäffer T. Respiratory physiology in sleep and wakefulness. HANDBOOK OF CLINICAL NEUROLOGY 2011; 98:371-81. [PMID: 21056199 DOI: 10.1016/b978-0-444-52006-7.00024-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Thorsten Schäffer
- Medical Faculty, Ruhr-University Bochum and Institute of Clinical Physiology, Helios Klinik Hagen-Ambrock, Germany.
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22
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Longobardo GS, Evangelisti CJ, Cherniack NS. Influence of arousal threshold and depth of sleep on respiratory stability in man: analysis using a mathematical model. Exp Physiol 2009; 94:1185-99. [PMID: 19666692 DOI: 10.1113/expphysiol.2009.049007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We examined the effect of arousals (shifts from sleep to wakefulness) on breathing during sleep using a mathematical model. The model consisted of a description of the fluid dynamics and mechanical properties of the upper airways and lungs, as well as a controller sensitive to arterial and brain changes in CO(2), changes in arterial oxygen, and a neural input, alertness. The body was divided into multiple gas store compartments connected by the circulation. Cardiac output was constant, and cerebral blood flows were sensitive to changes in O(2) and CO(2) levels. Arousal was considered to occur instantaneously when afferent respiratory chemical and neural stimulation reached a threshold value, while sleep occurred when stimulation fell below that value. In the case of rigid and nearly incompressible upper airways, lowering arousal threshold decreased the stability of breathing and led to the occurrence of repeated apnoeas. In more compressible upper airways, to maintain stability, increasing arousal thresholds and decreasing elasticity were linked approximately linearly, until at low elastances arousal thresholds had no effect on stability. Increased controller gain promoted instability. The architecture of apnoeas during unstable sleep changed with the arousal threshold and decreases in elasticity. With rigid airways, apnoeas were central. With lower elastances, apnoeas were mixed even with higher arousal thresholds. With very low elastances and still higher arousal thresholds, sleep consisted totally of obstructed apnoeas. Cycle lengths shortened as the sleep architecture changed from mixed apnoeas to total obstruction. Deeper sleep also tended to promote instability by increasing plant gain. These instabilities could be countered by arousal threshold increases which were tied to deeper sleep or accumulated aroused time, or by decreased controller gains.
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Affiliation(s)
- G S Longobardo
- Department of Medicine, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark, NJ 07103, USA.
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Zamarrón C, García Paz V, Morete E, del Campo Matías F. Association of chronic obstructive pulmonary disease and obstructive sleep apnea consequences. Int J Chron Obstruct Pulmon Dis 2009; 3:671-82. [PMID: 19281082 PMCID: PMC2650593 DOI: 10.2147/copd.s4950] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Obstructive sleep apnea syndrome (OSAS) and chronic obstructive pulmonary disease (COPD) are two diseases that often coexist within an individual. This coexistence is known as overlap syndrome and is the result of chance rather than a pathophysiological link. Although there are claims of a very high incidence of OSAS in COPD patients, recent studies report that it is similar to the general population. Overlap patients present sleep-disordered breathing associated to upper and lower airway obstruction and a reduction in respiratory drive. These patients present unique characteristics, which set them apart from either COPD or OSAS patients. COPD and OSAS are independent risk factors for cardiovascular events and their coexistence in overlap syndrome probably increases this risk. The mechanisms underlying cardiovascular risk are still unclear, but may involve systemic inflammation, endothelial dysfunction, and tonic elevation of sympathetic neural activity. The treatment of choice for overlap syndrome in stable patients is CPAP with supplemental oxygen for correction of upper airway obstructive episodes and hypoxemia during sleep.
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Affiliation(s)
- Carlos Zamarrón
- Servicio de Neumología, Hospital Clínico Universitario de Santiago, Santiago, Spain.
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Abstract
The onset of sleep is associated with a variety of changes in both behavioral and physiologic states. Sleep is not a uniform state either: it has different stages that affect different areas of the brain and body. Nonrapid eye movement sleep stages are as different from rapid eye movement sleep as is wakefulness. Circadian rhythms of physiologic systems also impact wake, sleep, sleepiness, and alertness. There are characteristic changes in both sleep patterns and circadian rhythm that occur with aging. The cardiovascular, respiratory, endocrine and gastrointestinal systems also undergo changes with sleep onset. This article reviews the aspects of normal sleep, physiologic changes that occur in the human body with sleep, and how sleep changes over the lifespan.
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Affiliation(s)
- Nancy A Collop
- Division of Pulmonary/Critical Care Medicine, 1830 East Monument Street, Room 555, Johns Hopkins University, Baltimore, MD 21205, USA.
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Balbir A, Lande B, Fitzgerald RS, Polotsky V, Mitzner W, Shirahata M. Behavioral and respiratory characteristics during sleep in neonatal DBA/2J and A/J mice. Brain Res 2008; 1241:84-91. [PMID: 18817755 DOI: 10.1016/j.brainres.2008.09.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2008] [Revised: 09/05/2008] [Accepted: 09/08/2008] [Indexed: 11/15/2022]
Abstract
The ventilatory response to hypoxia depends on the carotid body function and sleep-wake states. Therefore, the response must be measured in a consistent sleep-wake state. In mice, EMG with behavioral indices (coordinated movements, CMs; myoclonic twitches, MTs) has been used to assess sleep-wake states. However, in neonatal mice EMG instrumentation could induce stress, altering their behavior and ventilation. Accordingly, we examined: (1) if EMG can be eliminated for assessing sleep-wake states; and (2) behavioral characteristics and carotid body-mediated respiratory control during sleep with EMG (EMG+) or without EMG (EMG-). Seven-day-old DBA/2J and A/J mice were divided into EMG+ and EMG- groups. In both strains, CMs occurred when EMG was high; MTs were present during silent/low EMG activity. The durations of high EMG activity and of CMs were statistically indifferent. Thus, CMs can be used to indicate wake state without EMG. The stress caused by EMG instrumentation may be distinctively manifested based on genetic background. Prolonged agitation was observed in some EMG+ DBA/2J (5 of 13), but not in A/J mice. The sleep time and MT counts were indifferent between the groups in DBA/2J mice. The EMG+ A/J group showed longer sleep time and less MT counts than the EMG- A/J group. Mean respiratory variables (baseline, hyperoxic/hypoxic responses) were not severely influenced by EMG+ in either strain. Individual values were more variable in EMG+ mice. Carotid body-mediated respiratory responses (decreased ventilation upon hyperoxia and increased ventilation upon mild hypoxia) during sleep were clearly observed in these neonatal mice with or without EMG instrumentation.
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Affiliation(s)
- Alexander Balbir
- Division of Physiology, Department of Environmental Health Sciences, The Johns Hopkins Bloomberg School of Public Health, E7610, 615 N. Wolfe Street, Baltimore, MD 21205, USA
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26
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Ng ACC, Freedman SB. Sleep disordered breathing in chronic heart failure. Heart Fail Rev 2008; 14:89-99. [PMID: 18548345 DOI: 10.1007/s10741-008-9096-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2008] [Accepted: 05/13/2008] [Indexed: 12/12/2022]
Abstract
Heart failure is a growing problem, placing an increasing burden on public health resources and continuing to exert a high toll in mortality and morbidity. Sleep disordered breathing (SDB) is also a major public health problem and is associated with an increased risk of fatal and non-fatal cardiovascular events. Current evidence suggests SDB, particularly central SDB, is more prevalent in patients with chronic heart failure (CHF) than in the general population, but is under-diagnosed as SDB symptoms are less prevalent in CHF. This is further hampered by the absence of a simple and accurate screening tool and limited access to sleep facilities to diagnose SDB in the large numbers of patients with CHF. The presence of SDB in patients with CHF imposes increased haemodynamic burdens and results in autonomic abnormalities. Central SDB is an independent marker of worse prognosis, and evidence is increasing that obstructive SDB is also associated with higher mortality in patients with CHF. Optimal treatment of central SDB in these patients remains uncertain. While evidence of efficacy of positive pressure ventilation is stronger in obstructive SDB, improvement in survival for patients with both CHF and SDB awaits definitive trials. This paper summarizes our current understanding of the pathophysiology of SDB in CHF, and the cardiovascular consequences, and reviews the evidence for the beneficial effects of treatment of SDB in patients with CHF.
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Affiliation(s)
- Austin Chin Chwan Ng
- Faculty of Medicine, Concord RG Hospital, The University of Sydney, Hospital Road, Concord, 2139 NSW, Australia.
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Darnall RA, Ariagno RL, Kinney HC. The late preterm infant and the control of breathing, sleep, and brainstem development: a review. Clin Perinatol 2006; 33:883-914; abstract x. [PMID: 17148011 DOI: 10.1016/j.clp.2006.10.004] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The brainstem development of infants born between 33 and 38 weeks' gestation is less mature than that of a full-term infant. During late gestation, there are dramatic and nonlinear developmental changes in the brainstem. This translates into immaturity of upper airway and lung volume control, laryngeal reflexes, chemical control of breathing, and sleep mechanisms. Ten percent of late preterm infants have significant apnea of prematurity and they frequently have delays in establishing coordination of feeding and breathing. Unfortunately, there is a paucity of clinical, physiologic, neuroanatomic, and neurochemical data in this specific group of infants. Research focused on this group of infants will not only further our understanding of brainstem maturation during this high risk period, but will help develop focused plans for their management.
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Affiliation(s)
- Robert A Darnall
- Department of Physiology, Dartmouth-Hitchcock Medical Center, Lebanon, NH 03756, USA.
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28
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Xia L, Damon TA, Leiter JC, Bartlett D. Focal warming in the nucleus of the solitary tract prolongs the laryngeal chemoreflex in decerebrate piglets. J Appl Physiol (1985) 2006; 102:54-62. [PMID: 16959905 DOI: 10.1152/japplphysiol.00720.2006] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The laryngeal chemoreflex (LCR), elicited by a drop of water in the larynx, is exaggerated by mild hyperthermia (body temperature = 40-41 degrees C) in neonatal piglets. We tested the hypothesis that thermal prolongation of the LCR results from heating the nucleus of the solitary tract (NTS), where laryngeal afferents first form synapses in the brain stem. Three- to 13-day-old piglets were decerebrated and vagotomized and studied without anesthesia while paralyzed and ventilated. Phrenic nerve activity and rectal temperature were recorded. A thermode was placed in the medulla, and the brain tissue temperature was recorded with a thermistor approximately 1 mm from the tip of the thermode. When the thermode was inserted into the brain stem, respiratory activity was arrested or greatly distorted in eight animals. However, the thermode was inserted in nine animals without disrupting respiratory activity, and in these animals, warming the medullary thermode (thermistor temperature = 40-41 degrees C) while holding rectal temperature constant reversibly exaggerated the LCR. The caudal raphé was warmed focally by approximately 2 degrees C in four additional animals; this did not alter the duration of the LCR in these animals. Thermodes placed in the NTS did not disrupt respiratory activity, but they did prolong the LCR when warmed. Thermodes that were placed deep to the NTS in the region of the nucleus ambiguus disrupted respiratory activity, which precluded any analysis of the LCR. We conclude that prolongation of the laryngeal chemoreflex by whole body hyperthermia originates from the elevation of brain tissue temperature within in the NTS.
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Affiliation(s)
- L Xia
- Department of Physiology, Dartmouth Medical School, Lebanon, NH 03756, USA
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