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Curtis JA, Huber JE, Dakin AE, Troche MS. Effects of Bolus Holding on Respiratory-Swallow Coordination in Parkinson's Disease. AMERICAN JOURNAL OF SPEECH-LANGUAGE PATHOLOGY 2022; 31:705-721. [PMID: 34752144 DOI: 10.1044/2021_ajslp-21-00044] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
PURPOSE The aim of this study was to examine the effects of bolus holding on respiratory-swallow coordination (RSC) in people with Parkinson's disease (PD). METHOD People with PD were prospectively recruited to undergo RSC assessment using simultaneous respiratory inductive plethysmography and flexible laryngoscopy. During RSC assessment, participants swallowed 5-ml thin liquid boluses during held and nonheld swallowing tasks. Measures of RSC were analyzed for each swallow, which included respiratory pause duration, lung volume at swallow initiation, respiratory phase patterning, and the presence of paradoxical respiratory movements. Multilevel statistical modeling was used to determine if differences in RSC were present between the held and nonheld tasks. RESULTS Thirty-three participants were enrolled. When compared to the nonheld swallows, the held swallows exhibited shorter respiratory pauses (p = .001, R 2 = .019), lower lung volumes at swallow initiation (p < .001, R 2 = .116), more frequent exhale-swallow-exhale patterns (p < .001, OR = 4.30), and less frequent paradoxical respiratory movements (p = .001, OR = 0.43). CONCLUSIONS Findings from this study revealed that bolus holding significantly influences RSC in people with PD. This demonstrates that bolus holding may be an efficacious strategy to immediately improve RSC in PD. However, clinicians and researchers should consider avoiding bolus holding during swallowing evaluations if attempting to assess RSC behaviors that are most typical for the examinee.
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Affiliation(s)
- James A Curtis
- Laboratory for the Study of Upper Airway Dysfunction, Department of Biobehavioral Sciences, Teachers College, Columbia University, New York, NY
| | | | - Avery E Dakin
- Laboratory for the Study of Upper Airway Dysfunction, Department of Biobehavioral Sciences, Teachers College, Columbia University, New York, NY
| | - Michelle S Troche
- Laboratory for the Study of Upper Airway Dysfunction, Department of Biobehavioral Sciences, Teachers College, Columbia University, New York, NY
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Drulia TC, Kamarunas E, O'Donoghue C, Ludlow CL. An Exploration of Lung Volume Effects on Swallowing in Chronic Obstructive Pulmonary Disease. AMERICAN JOURNAL OF SPEECH-LANGUAGE PATHOLOGY 2021; 30:2155-2168. [PMID: 34411488 DOI: 10.1044/2021_ajslp-20-00389] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Purpose Chronic obstructive pulmonary disease (COPD) limits respiration, which may negatively impact airway safety during swallowing. It is unknown how differences in lung volume in COPD may alter swallowing physiology. This exploratory study aimed to determine how changes in lung volume impact swallow duration and coordination in persons with stable state COPD compared with older healthy volunteers (OHVs). Method Volunteers ≥ 45 years with COPD (VwCOPDs; n = 9) and OHVs (n = 10) were prospectively recruited. Group and within-participant differences were examined when swallowing at different respiratory volumes: resting expiratory level (REL), tidal volume (TV), and total lung capacity (TLC). Participants swallowed self-administered 20-ml water boluses by medicine cup. Noncued (NC) water swallows were followed by randomly ordered block swallowing trials at three lung volumes. Estimated lung volume (ELV) and respiratory-swallow patterning were quantified using spirometry and respiratory inductive plethysmography. Manometry measured pharyngeal swallow duration from onset of base of tongue pressure increase to offset of negative pressure in the pharyngoesophageal segment. Results During NC swallows, the VwCOPDs swallowed at lower lung volumes than OHVs (p = .011) and VwCOPDs tended to inspire after swallows more often than OHVs. Pharyngeal swallow duration did not differ between groups; however, swallow duration significantly decreased as the ELV increased in VwCOPDs (p = .003). During ELV manipulation, the COPD group inspired after swallowing more frequently at REL than at TLC (p = .001) and at TV (p = .002). In conclusion, increasing respiratory lung volume in COPD should improve safety by reducing the frequency of inspiration after a swallow.
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Affiliation(s)
- Teresa C Drulia
- Department of Communication Sciences and Disorders, James Madison University, Harrisonburg, VA
- Davies School of Communication Sciences and Disorders, Texas Christian University, Fort Worth
| | - Erin Kamarunas
- Department of Communication Sciences and Disorders, James Madison University, Harrisonburg, VA
| | - Cynthia O'Donoghue
- Department of Communication Sciences and Disorders, James Madison University, Harrisonburg, VA
| | - Christy L Ludlow
- Department of Communication Sciences and Disorders, James Madison University, Harrisonburg, VA
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Yamaguchi-Komeyama K, Ayuse T, Mikushi S, Hisamatsu N, Yamaguchi T, Magata N, Tanoue N, Kawasaki H, Kozu R, Takahata H, Ayuse T. The pilot study examining the effects of swallowing position on lung volume fraction and the coordination between respiration and non-nutritive swallowing reflex. Clin Exp Dent Res 2020; 6:296-304. [PMID: 32067414 PMCID: PMC7301395 DOI: 10.1002/cre2.274] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 11/24/2019] [Accepted: 11/28/2019] [Indexed: 11/25/2022] Open
Abstract
Background Body position might affect the coordination between respiration and swallowing. This study was carried out to test the hypothesis that during swallowing, coordinated movements of muscle groups such as the diaphragm and rectus abdominis muscles are important to control normal swallowing apnea. Objective To investigate this hypothesis, respiratory parameters, swallowing apnea and muscle activity were measured in each of four body positions: sitting position with feet on the floor, 30° reclining position, lateral position, and standing position. Methods All measurements were performed in nine healthy subjects. Nasal airflow was measured using a pneumotachometer and muscle activity was measured using an electromyograph. All lung volume fraction parameters were measured using spirometer and swallowing apnea time was calculated. Results The maximum inspiratory volume was 2.76 ± 0.83 L in the 30° reclining position, which was significantly larger than that in the other positions (p = .0001). The preliminary expiratory volume was 1.05 ± 0.42 L in the 30° reclining position, which was significantly smaller than that in the other positions (p < .0001). The swallowing apnea time during water swallowing was 1.17 ± 0.35 sec in the lateral position and 0.87 ± 0.28 sec in the 30° reclining position, which tended to be longer than the 0.78 sec in the sitting position. Conclusion We conclude that both lateral and reclining positions require a longer period of swallowing apnea compared to the sitting and standing positions. Differences in body position may significantly influence the coordination between respiration and swallowing.
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Affiliation(s)
- Kaori Yamaguchi-Komeyama
- Department of Special Care Dentistry, Nagasaki University Hospital of Medicine and Dentistry, Nagasaki, Japan
| | - Terumi Ayuse
- Department of Special Care Dentistry, Nagasaki University Hospital of Medicine and Dentistry, Nagasaki, Japan
| | - Shinya Mikushi
- Department of Special Care Dentistry, Nagasaki University Hospital of Medicine and Dentistry, Nagasaki, Japan
| | - Noriko Hisamatsu
- Department of Special Care Dentistry, Nagasaki University Hospital of Medicine and Dentistry, Nagasaki, Japan
| | - Taiki Yamaguchi
- Department of Special Care Dentistry, Nagasaki University Hospital of Medicine and Dentistry, Nagasaki, Japan
| | - Nobuaki Magata
- Department of Special Care Dentistry, Nagasaki University Hospital of Medicine and Dentistry, Nagasaki, Japan
| | - Naomi Tanoue
- Department of Special Care Dentistry, Nagasaki University Hospital of Medicine and Dentistry, Nagasaki, Japan
| | - Hanako Kawasaki
- Department of Special Care Dentistry, Nagasaki University Hospital of Medicine and Dentistry, Nagasaki, Japan
| | - Ryo Kozu
- Department of Cardiopulmonary Rehabilitation Science, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Hideaki Takahata
- Department of Rehabilitation Medicine, Nagasaki University Hospital, Nagasaki, Japan
| | - Takao Ayuse
- Department of Special Care Dentistry, Nagasaki University Hospital of Medicine and Dentistry, Nagasaki, Japan.,Department of Dental Anesthesiology, Course of Medical and Dental Sciences, Nagasaki University Institute of Biomedical Sciences, Nagasaki, Japan
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Horton KK, Segers LS, Nuding SC, O'Connor R, Alencar PA, Davenport PW, Bolser DC, Pitts T, Lindsey BG, Morris KF, Gestreau C. Central Respiration and Mechanical Ventilation in the Gating of Swallow With Breathing. Front Physiol 2018; 9:785. [PMID: 30013484 PMCID: PMC6036260 DOI: 10.3389/fphys.2018.00785] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 06/05/2018] [Indexed: 11/13/2022] Open
Abstract
Swallow-breathing coordination safeguards the lower airways from tracheal aspiration of bolus material as it moves through the pharynx into the esophagus. Impaired movements of the shared muscles or structures of the aerodigestive tract, or disruptions in the interaction of brainstem swallow and respiratory central pattern generators (CPGs) result in dysphagia. To maximize lower airway protection these CPGs integrate respiratory rhythm generation signals and vagal afferent feedback to synchronize swallow with breathing. Despite extensive study, the roles of central respiratory activity and vagal feedback from the lungs as key elements for effective swallow-breathing coordination remain unclear. The effect of altered timing of bronchopulmonary vagal afferent input on swallows triggered during electrical stimulation of the superior laryngeal nerves or by injection of water into the pharyngeal cavity was studied in decerebrate, paralyzed, and artificially ventilated cats. We observed two types of single swallows that produced distinct effects on central respiratory-rhythm across all conditions: post-inspiratory type swallows disrupted central-inspiratory activity without affecting expiration, whereas expiratory type swallows prolonged expiration without affecting central-inspiratory activity. Repetitive swallows observed during apnea reset the E2 phase of central respiration and produced facilitation of swallow motor output nerve burst durations. Moreover, swallow initiation was negatively modulated by vagal feedback and was reset by lung inflation. Collectively, these findings support a novel model of reciprocal inhibition between the swallow CPG and inspiratory or expiratory cells of the respiratory CPG where lung distension and phases of central respiratory activity represent a dual peripheral and central gating mechanism of swallow-breathing coordination.
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Affiliation(s)
- Kofi-Kermit Horton
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
| | - Lauren S Segers
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
| | - Sarah C Nuding
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
| | - Russell O'Connor
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
| | - Pierina A Alencar
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
| | - Paul W Davenport
- Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL, United States
| | - Donald C Bolser
- Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL, United States
| | - Teresa Pitts
- Department of Neurological Surgery, Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, United States
| | - Bruce G Lindsey
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
| | - Kendall F Morris
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
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Rizwan A, Sankari A, Bascom AT, Vaughan S, Badr MS. Nocturnal swallowing and arousal threshold in individuals with chronic spinal cord injury. J Appl Physiol (1985) 2018; 125:445-452. [PMID: 29672224 DOI: 10.1152/japplphysiol.00641.2017] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Respiratory complications are potential causes of death in patients with spinal cord injury (SCI). Nocturnal swallowing could be related to transient arousals and could lead to fragmented sleep in SCI patients. However, the impact of nocturnal swallowing on breathing and sleep physiology in SCI is unknown. The objectives of this study were 1) to determine whether nocturnal swallowing is more common in SCI than in able-bodied (AB) subjects, 2) to determine the role of nocturnal swallowing on arousal threshold (ArTh) in SCI individuals with sleep-disordered breathing (SDB), and 3) to determine the effect of continuous positive airway pressure (CPAP) treatment on nocturnal swallowing. A total of 16 SCI and 13 AB subjects with SDB completed in-laboratory polysomnography with a pharyngeal catheter. A swallowing event (SW) was defined as a positive spike in pharyngeal pressure and was used to calculate the swallow index (SI) defined as a number of SW/total sleep time. Each SW was assessed for a relationship to the sleep stages and respiratory cycle phases, and associated arousals and ArTh were calculated. SI was higher in the SCI group compared with AB subjects during wake and different sleep stages ( P < 0.05). SWs were found to be significantly higher in the late expiratory phase in the group with SCI compared with the other respiratory phases and were eliminated by CPAP ( P < 0.05). ArTh for the subjects with SCI was significantly lower ( P < 0.05) compared with the AB subjects. Nocturnal swallowing is more common in SCI than in AB individuals who have SDB, particularly during the expiratory phase. The ArTh is significantly lower in SCI (indicating increased arousal propensity), which may contribute to the mechanism of sleep disturbances in SCI. NEW & NOTEWORTHY Nocturnal swallowing is common in patients with chronic spinal cord injury (SCI) and is associated with frequent arousals from sleep. The lower arousal threshold during sleep in SCI may contribute to the mechanism of sleep disturbances that are commonly found in cervical and high thoracic SCI. Continuous positive airway pressure may play a therapeutic role in alleviating nocturnal swallowing, which may contribute to reduced risk of aspiration.
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Affiliation(s)
- Aliza Rizwan
- Sleep Research Laboratory, John D. Dingell Veterans Affairs Medical Center , Detroit, Michigan.,Wayne State University School of Medicine , Detroit, Michigan
| | - Abdulghani Sankari
- Sleep Research Laboratory, John D. Dingell Veterans Affairs Medical Center , Detroit, Michigan.,Wayne State University School of Medicine , Detroit, Michigan
| | - Amy T Bascom
- Sleep Research Laboratory, John D. Dingell Veterans Affairs Medical Center , Detroit, Michigan.,Wayne State University School of Medicine , Detroit, Michigan
| | - Sarah Vaughan
- Sleep Research Laboratory, John D. Dingell Veterans Affairs Medical Center , Detroit, Michigan.,Wayne State University School of Medicine , Detroit, Michigan
| | - M Safwan Badr
- Sleep Research Laboratory, John D. Dingell Veterans Affairs Medical Center , Detroit, Michigan.,Wayne State University School of Medicine , Detroit, Michigan
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Bierens JJLM, Lunetta P, Tipton M, Warner DS. Physiology Of Drowning: A Review. Physiology (Bethesda) 2017; 31:147-66. [PMID: 26889019 DOI: 10.1152/physiol.00002.2015] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Drowning physiology relates to two different events: immersion (upper airway above water) and submersion (upper airway under water). Immersion involves integrated cardiorespiratory responses to skin and deep body temperature, including cold shock, physical incapacitation, and hypovolemia, as precursors of collapse and submersion. The physiology of submersion includes fear of drowning, diving response, autonomic conflict, upper airway reflexes, water aspiration and swallowing, emesis, and electrolyte disorders. Submersion outcome is determined by cardiac, pulmonary, and neurological injury. Knowledge of drowning physiology is scarce. Better understanding may identify methods to improve survival, particularly related to hot-water immersion, cold shock, cold-induced physical incapacitation, and fear of drowning.
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Affiliation(s)
| | - Philippe Lunetta
- Department of Pathology and Forensic Medicine, University of Turku, Turku, Finland
| | - Mike Tipton
- Department of Sport and Exercise Science, Extreme Environments Laboratory, University of Portsmouth, Portsmouth, United Kingdom; and
| | - David S Warner
- Departments of Anesthesiology, Neurobiology and Surgery, Duke University Medical Center, Durham, North Carolina
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7
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Sleep Stage Coordination of Respiration and Swallowing: A Preliminary Study. Dysphagia 2016; 31:579-86. [PMID: 27338262 DOI: 10.1007/s00455-016-9719-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Accepted: 06/14/2016] [Indexed: 10/21/2022]
Abstract
Swallowing is an important physiological response that protects the airway. Although aspiration during sleep may cause aspiration pneumonia, the mechanisms responsible have not yet been elucidated. We evaluated the coordination between respiration and swallowing by infusing water into the pharynx of healthy young adults during each sleep stage. Seven normal subjects participated in the study. During polysomnography recordings, to elicit a swallow we injected distilled water into the pharynx during the awake state and each sleep stage through a nasal catheter. We assessed swallow latency, swallow apnea time, the respiratory phase during a swallow, the number of swallows, and coughing. A total number of 79 swallows were recorded. The median swallow latency was significantly higher in stage 2 (10.05 s) and stage 3 (44.17 s) when compared to awake state (4.99 s). The swallow latency in stage 3 showed a very wide interquartile range. In two subjects, the result was predominantly prolonged compared to the other subjects. There was no significant difference in the swallow apnea time between sleep stages. The presence of inspiration after swallowing, repetitive swallowing, and coughing after swallowing was more frequent during sleep than when awake. This study suggests that the coordination between respiration and swallowing as a defense mechanism against aspiration was impaired during sleep. Our results supported physiologically the fact that healthy adult individuals aspirate pharyngeal secretions during sleep.
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Zheng Z, Wu Z, Liu N, Chen P, Hou P, Wang X, Fu Y, Liang W, Chen R. Silent aspiration in patients with exacerbation of COPD. Eur Respir J 2016; 48:570-3. [DOI: 10.1183/13993003.00007-2016] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 04/18/2016] [Indexed: 11/05/2022]
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Cassiani RA, Santos CM, Baddini-Martinez J, Dantas RO. Oral and pharyngeal bolus transit in patients with chronic obstructive pulmonary disease. Int J Chron Obstruct Pulmon Dis 2015; 10:489-96. [PMID: 25784795 PMCID: PMC4356708 DOI: 10.2147/copd.s74945] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Patients with respiratory diseases, such as chronic obstructive pulmonary disease (COPD), may have swallowing dysfunction. OBJECTIVE The aim of this investigation was to evaluate the oral and pharyngeal phases of swallowing in patients with COPD. METHODS We studied 16 patients with clinical manifestations and pulmonary function tests diagnosis of COPD (mean age: 68 years) and 15 nonsmoking healthy volunteers (mean age: 65 years) with normal pulmonary function tests. All subjects were submitted to clinical and videofluoroscopic evaluation of swallowing. Each subject performed in duplicate swallows of 5 mL and 10 mL of liquid bolus, paste bolus, and a solid bolus. RESULTS In general, the duration of the events of the pharyngeal phase of swallowing was longer in COPD patients than controls. The difference was significant in the laryngeal vestibular closure, hyoid movement, and pharyngeal transit with swallows of both volumes of liquid bolus; in oral-pharyngeal transit with 5 mL paste bolus; and in pharyngeal and oral-pharyngeal transit with solid bolus. The difference between the duration of maximal laryngeal elevation and the duration of pharyngeal transit was higher in control subjects than in patients with COPD. CONCLUSION The results suggested that patients with COPD have a longer pharyngeal swallowing phase than normal subjects, which is associated with a decrease in the difference between the duration of maximal laryngeal elevation and the duration of pharyngeal transit.
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Affiliation(s)
- Rachel Aguiar Cassiani
- Department of Medicine, Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Carla Manfredi Santos
- Department of Medicine, Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - José Baddini-Martinez
- Department of Medicine, Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Roberto Oliveira Dantas
- Department of Medicine, Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
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Affiliation(s)
- Hameeda Shaikh
- Pulmonary and Critical Care Section, Edward Hines, Jr. Veterans Affairs Hospital, Hines, IL Division of Pulmonary and Critical Care Medicine, Edward Hines, Jr. Veterans Affairs Hospital, Hines, IL; and, Division of Pulmonary and Critical Care, Department of Medicine, Loyola University, Maywood, IL
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11
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Residual neuromuscular blockade after anesthesia: a possible cause of postoperative aspiration-induced pneumonia. Anesthesiology 2014; 120:260-2. [PMID: 24451412 DOI: 10.1097/aln.0000000000000042] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Nishino T. The swallowing reflex and its significance as an airway defensive reflex. Front Physiol 2013; 3:489. [PMID: 23316169 PMCID: PMC3539657 DOI: 10.3389/fphys.2012.00489] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Accepted: 12/15/2012] [Indexed: 12/04/2022] Open
Abstract
Swallowing function, in humans, is very complex. Swallowing plays, not only an important role in food digestion, but also a major role in preventing the entrance of food and/or other materials into the lower respiratory tract. To achieve this, precise coordination is necessary between breathing and swallowing since the pharynx serves as a common pathway for both respiration and digestion. The swallowing reflex consists of afferent pathways, central integration, and efferent pathways. Any defect or disorder along reflex arc can cause a potential delay or impairment in swallow function. The swallowing reflex can be modulated not only by pathological factors but also by physiological factors. Among these, timing of swallows in relation to the phase of respiration may be the most important factor that determines the occurrence of pulmonary aspiration, since phases of inspiration and the expiration-inspiration transition are the most vulnerable for pulmonary aspiration.
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Aras G, Kanmaz D, Kadakal F, Purisa S, Sonmez K, Tuncay E, Ozdemir A. Gastroesophageal reflux disease in our asthma patients: the presence of dysphagia can influence pulmonary function. Multidiscip Respir Med 2012; 7:53. [PMID: 23244779 PMCID: PMC3558373 DOI: 10.1186/2049-6958-7-53] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Accepted: 11/30/2012] [Indexed: 12/21/2022] Open
Abstract
Background The prevalence of Gastroesophageal Reflux Disease (GERD) in Turkey is reported as 11.6%. Studies of pulmonary function in asthmatics have demonstrated a correlation between lung resistance and the occurrence of spontaneous gastroesophageal reflux. Few studies have included measures of lung diffusing capacity for carbon monoxide. The aim of this study is to assess whether asthma patients had worse lung function and gas diffusion according to diversity of GERD symptoms they concurrently experienced. The secondary aim of the study is to determine the frequency and different faces of GERD in our asthma patients compared to healthy controls. Methods Sixty consecutive asthma patients evaluatd at the pulmonary specialty outpatient clinic were included in the study. The control group included 60 healthy volunteers who had normal pulmonary function and routine laboratory tests. A modified version of a self-reported questionnaire developed by Locke and associates at the Mayo Clinic was conducted face-to-face with consecutive asthma patients and control subjects. Pulmonary function measurements were taken using spirometry. DLCO (mL/dk/mmHg) and DLCO/VA (DLCO adjusted according to alveolar volume) were measured using a single-breath technique. Statistical analyses were performed using the SPSS 17.0 statistical software. Results DLCO and DLCO/VA were significantly lower in asthma patients who had dysphagia symptoms. Frequent and significant acid regurgitations were seen in 28.33% (n = 17) of patients in the study group and 6.7% (n = 4) of patients in the control group. Severe, troublesome heartburn symptoms were reported by 28.2% (n = 17) of patients in the study group and 16.7% (n = 10) of subjects in the control group. Dysphagia was detected in 38.3% (n = 23) of all asthma cases and in 1.7% (n = 1) of the subjects in the control group. Conclusions There were many faces of gastroesophageal reflux disease in our asthmatic patients. Dysphagia was the only GERD symptom influencing on pulmonary function tests, while gastroesophageal reflux symptoms and nocturnal awakening attacks were common in this study.
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Affiliation(s)
- Gulfidan Aras
- Yedikule Chest Disease and Surgery Education and Research Hospital, Istanbul, Turkey.
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Bernier A, Catelin C, Ahmed MAH, Samson N, Bonneau P, Praud JP. Effects of nasal continuous positive-airway pressure on nutritive swallowing in lambs. J Appl Physiol (1985) 2012; 112:1984-91. [PMID: 22500003 DOI: 10.1152/japplphysiol.01559.2011] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Current knowledge suggests that, to be successful, oral feeding in preterm infants should be initiated as soon as possible, often at an age where immature respiration still requires ventilatory support in the form of nasal continuous positive airway pressure (nCPAP). While some neonatologist teams claim great success with initiation of oral feeding in immature infants with nCPAP, others strictly wait for this ventilatory support to be no longer necessary before any attempt at oral feeding, fearing laryngeal penetration and tracheal aspiration. Therefore, the aim of the present study was to provide a first assessment of the effect of various levels of nCPAP on bottle-feeding in a neonatal ovine model, including feeding safety, feeding efficiency, and nutritive swallowing-breathing coordination. Eight lambs born at term were surgically instrumented 48 h after birth to collect recordings of electrical activity of laryngeal constrictor muscle, electrocardiography, and arterial blood gases. Two days after surgery, lambs were bottle-fed under five randomized nCPAP conditions, including without any nCPAP or nasal mask and nCPAP of 0, 4, 7, and 10 cmH(2)O. Results revealed that application of nCPAP in the full-term lamb had no deleterious effect on feeding safety and efficiency or on nutritive swallowing-breathing coordination. The present study provides a first and unique insight on the effect of nCPAP on oral feeding, demonstrating its safety in newborn lambs born at term. These results open the way for further research in preterm lambs to better mimic the problems encountered in neonatology.
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Affiliation(s)
- Anne Bernier
- Neonatal Respiratory Research Unit, Department of Pediatrics, Université de Sherbrooke, Sherbrooke, J1H 5N4, QC Canada
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Chaves RDD, Carvalho CRFD, Cukier A, Stelmach R, Andrade CRFD. Symptoms of dysphagia in patients with COPD. J Bras Pneumol 2011; 37:176-83. [PMID: 21537653 DOI: 10.1590/s1806-37132011000200007] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2010] [Accepted: 02/24/2011] [Indexed: 11/21/2022] Open
Abstract
OBJECTIVE To identify symptoms of dysphagia in individuals with COPD, based on their responses on a self-perception questionnaire. METHODS The study comprised 35 individuals with COPD and 35 healthy individuals, matched for age and gender. The study group was assessed regarding COPD severity; sensation of dyspnea; body mass index (BMI); and symptoms of dysphagia. The control group was assessed regarding BMI and symptoms of dysphagia. RESULTS The most common symptoms of dysphagia in the study group were pharyngeal symptoms/airway protection (p < 0.001); esophageal symptoms/history of pneumonia (p < 0.001); and nutritional symptoms (p < 0.001). Positive correlations were found between the following pairs of variables: FEV₁ and BMI (r = 0.567; p < 0.001); pharyngeal symptoms/airway protection and dyspnea (r = 0.408; p = 0.015); and esophageal symptoms/history of pneumonia and pharyngeal symptoms/airway protection (r = 0.531; p = 0.001). There was a negative correlation between nutritional symptoms and BMI (r = -0.046; p < 0.008). CONCLUSIONS Our results show that the individuals with COPD presented with symptoms of dysphagia that were associated with the pharyngeal and esophageal phases of swallowing, as well as with the mechanism of airway protection, a history of pneumonia, and nutritional symptoms.
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Affiliation(s)
- Rosane de Deus Chaves
- Programa de Pós-Graduação em Ciências da Reabilitação, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brasil
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Hårdemark Cedborg AI, Sundman E, Bodén K, Hedström HW, Kuylenstierna R, Ekberg O, Eriksson LI. Co-ordination of spontaneous swallowing with respiratory airflow and diaphragmatic and abdominal muscle activity in healthy adult humans. Exp Physiol 2009; 94:459-68. [DOI: 10.1113/expphysiol.2008.045724] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Wheeler Hegland KM, Huber JE, Pitts T, Sapienza CM. Lung volume during swallowing: single bolus swallows in healthy young adults. JOURNAL OF SPEECH, LANGUAGE, AND HEARING RESEARCH : JSLHR 2009; 52:178-187. [PMID: 18723599 DOI: 10.1044/1092-4388(2008/07-0165)] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
PURPOSE This study examined the relationship between swallowing and lung volume initiation in healthy adults during single swallows of boluses differing in volume and consistency. Differences in lung volume according to respiratory phase surrounding the swallow were also assessed. METHOD Nine men and 11 women between the ages of 19 and 28 years served as study participants. Lung volume and respiratory phase data were recorded as each participant completed 5 trials each of 10-mL and 20-mL water boluses by cup, and thin and thick paste boluses by spoon, presented in randomized order. RESULTS Significant differences in lung volume at swallow initiation were found based on bolus consistency but not on bolus volume. No differences were found for lung volume initiation based on the respiratory phase surrounding the swallow or for the respiratory pattern based on bolus volume or consistency. CONCLUSION Findings of this study extend the existing knowledge base regarding the interaction of the swallow and respiratory systems by identifying targeted lung volumes at swallow initiation. In addition to other swallow-related biomechanical events and respiratory phase relationships surrounding a swallow, the lung volume at swallow initiation may be an important consideration when investigating swallow physiology and physiopathy.
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Samson N, Roy B, Ouimet A, Moreau-Bussière F, Dorion D, Mayer S, Praud JP. Origins of the inhibiting effects of nasal CPAP on nonnutritive swallowing in newborn lambs. J Appl Physiol (1985) 2008; 105:1083-90. [DOI: 10.1152/japplphysiol.90494.2008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The present study investigated the mechanism by which continuous positive airway pressure (CPAP) suppresses nonnutritive swallowing (NNS) during quiet sleep (QS) in newborn lambs. Eighteen full-term lambs were chronically instrumented and evenly distributed into three separate groups to determine the extent to which modulation of NNS may be attributed to stimulation of upper airway and/or bronchopulmonary mechanoreceptors. Six lambs were tracheotomized, six other lambs underwent a two-step bilateral intrathoracic vagotomy, and the remaining six lambs underwent chronic laryngotracheal separation (isolated upper airway group). Forty-eight hours after surgery, each nonsedated lamb underwent polysomnographic recordings on three consecutive days. States of alertness, NNS and respiratory movements were recorded. Results demonstrate that a CPAP of 6 cmH2O inhibited NNS during QS while administered directly on the lower airways and that bivagotomy prevented this inhibition. However, application of CPAP on the upper airways only also inhibited NNS during QS. Finally, the application of a CPAP of 6 cmH2O had no systematic effect on NNS-breathing coordination (assessed by the respiratory phase preceding and following NNS). In conclusion, our results suggest that bronchopulmonary receptors are implicated in the inhibiting effects of nasal CPAP of 6 cmH2O on NNS in all our experimental conditions, whereas upper airway receptors are only implicated in certain conditions.
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Kurozumi C, Yamagata R, Himi N, Koga T. Emetic stimulation inhibits the swallowing reflex in decerebrate rats. Auton Neurosci 2008; 140:24-9. [PMID: 18396466 DOI: 10.1016/j.autneu.2008.02.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2007] [Revised: 02/27/2008] [Accepted: 02/27/2008] [Indexed: 10/22/2022]
Abstract
The effects of emetic stimulation on the swallowing reflex were investigated in decerebrated rats. Hypoxia, gastric distension and LiCl administration were used as emetic stimulations. The swallowing reflex was elicited by electrical stimulation of the superior laryngeal nerve (SLN, 20 Hz, 3-5 V, 0.3 ms duration) for 20 s. To examine the effect of hypoxia, nitrogen gas was inhaled under artificial ventilation. There were significantly fewer swallows during a decrease in PO(2) than under air ventilation (p<0.05). The number of swallows during 3-ml stomach distension was significantly lower than that before distension (p<0.05). Intravenous administration of LiCl (100 mg/kg) also significantly reduced the number of swallows (p<0.05). The combination of SLN stimulation and emetic stimuli occasionally produced burst activity of abdominal muscles, which might be associated with the gag reflex. Both the gag and swallowing reflexes are well known to be mediated by the nucleus of the solitary tract. The physiological roles of the gag reflex and the swallowing reflex are considered to be reciprocal. Taken together, these results suggest that emetic stimulation inhibits the swallowing pattern generator via the nucleus of the solitary tract, which in turn facilitates the gag reflex.
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Affiliation(s)
- Chiharu Kurozumi
- Department of Rehabilitation, Kawasaki University of Medical Welfare, Kurashiki 701-0193, Japan
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20
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CPAP inhibits non-nutritive swallowing through stimulation of bronchopulmonary receptors. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2008. [PMID: 18085310 DOI: 10.1007/978-0-387-73693-8_73] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register]
Abstract
While swallowing and respiratory problems are among the most frequent disorders encountered in neonates, the interrelationships between both functions are not completely understood. This is especially true for non-nutritive swallowing (NNS), which fulfills the important function of clearing upper airways from both local secretions and liquids refluxed from the stomach. Recently, we showed that nasal CPAP inhibits NNS during quiet sleep in the newborn lamb (Samson, St-Hilaire, Nsegbe, Reix, Moreau-Bussière and Praud 2005). The present study was aimed at testing the hypothesis that NNS inhibition is eliminated when CPAP is directly administered through a tracheostomy, thus eliminating reflexes originating from upper airway receptors. Results show that both nasal and tracheal CPAP 6cm H2O similarly inhibit total NNS during quiet sleep, thus suggesting that the inhibiting effect of nasal CPAP on NNS is mainly mediated through bronchopulmonary mechanical receptors with minimal participation of the upper airways.
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Ayuse T, Ayuse T, Ishitobi S, Kurata S, Sakamoto E, Okayasu I, Oi K. Effect of reclining and chin-tuck position on the coordination between respiration and swallowing. J Oral Rehabil 2007; 33:402-8. [PMID: 16671985 DOI: 10.1111/j.1365-2842.2005.01586.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Chin-tuck position and reclining posture have been used in dysphagia patients to prevent aspiration during swallowing. However, both behavioural treatments may affect respiratory function. This study was carried out to test the hypothesis that if chin-tuck posture and body reclining affected respiratory function, this would be associated with altered coordination between respiration and swallowing. To investigate this hypothesis, respiratory parameters and manometry were used in each of four combinations of reclining posture and chin-tuck position. In the 60 degrees reclining with 60 degrees chin-tuck position, duration of swallowing apnea (0.89 s.d. 0.17 s) and submental electromyography burst (2.34 s.d. 0.84 s) were significantly longer when compared to both upright sitting and 30 degrees reclining positions. We conclude that 60 degrees reclining from vertical with 60 degrees chin-tuck may affect oral processing stages which delay and reduce a variety of oropharyngeal movements. These in turn significantly influence the coordination between respiration and swallowing.
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Affiliation(s)
- T Ayuse
- Department of Special Care Dentistry, Nagasaki University Hospital of Medicine and Dentistry, Nagasaki, Japan
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22
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Samson N, St-Hilaire M, Nsegbe E, Reix P, Moreau-Bussière F, Praud JP. Effect of nasal continuous or intermittent positive airway pressure on nonnutritive swallowing in the newborn lamb. J Appl Physiol (1985) 2005; 99:1636-42. [PMID: 15976359 DOI: 10.1152/japplphysiol.00464.2005] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The present study was aimed at investigating the effects of nasal continuous positive airway pressure (nCPAP; 6 cmH2O) or intermittent positive pressure ventilation (nIPPV; 10/4 cmH2O) on nonnutritive swallowing (NNS) and on the coordination between NNS and phases of the respiratory cycle, while taking into account the potential effects of states of alertness. Twelve full-term lambs were chronically instrumented at 48 h after birth for polysomnographic recordings, including NNS, diaphragm electromyographic activity, respiratory movements, pulse oximetry, and states of alertness. Studies in control conditions, with nCPAP and nIPPV, were performed in random order in nonsedated lambs at 4, 5, and 6 days of life. Results demonstrate that nCPAP significantly decreased overall NNS frequency, more specifically isolated NNS during quiet sleep and bursts of NNS in active sleep. In comparison, the effects of nIPPV on NNS frequency were more variable, with an inhibition of NNS only in wakefulness and an increase in isolated NNS frequency in active sleep. In addition, neither nCPAP nor nIPPV disrupted the coordination between NNS and phases of the respiratory cycle. In conclusion, nCPAP inhibits NNS occurrence in newborn lambs. Clinical relevance of this novel finding is related to the importance of NNS for clearing the upper airways from secretions and gastric content frequently regurgitated in the neonatal period.
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Affiliation(s)
- Nathalie Samson
- Neonatal Respiratory Research Unit, Department of Pediatrics, University of Sherbrooke, Sherbrooke, Quebec, Canada
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23
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Reix P, Duvareille C, Létourneau P, Pouliot M, Samson N, Niyonsenga T, Praud JP. C-fiber blockade influence on non-nutritive swallowing in full-term lambs. Respir Physiol Neurobiol 2005; 152:27-35. [PMID: 16153898 DOI: 10.1016/j.resp.2005.07.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2004] [Revised: 07/09/2005] [Accepted: 07/14/2005] [Indexed: 11/24/2022]
Abstract
Systemic C-fiber blockade (CFB) has been reported to inhibit induced swallowing in adult guinea pigs. The aim of this study was to investigate the effects of CFB on spontaneous, non-nutritive swallowing (NNS) frequency and NNS-respiration coordination in the neonatal period. Seven CFB lambs and seven control lambs aged 2+/-1 days were chronically instrumented for recording electroencephalogram, eye movements, diaphragm EMG, thyroarytenoid muscle EMG, nasal airflow and electrocardiogram. Polysomnographic recordings were performed in non-sedated lambs, using radiotelemetry transmission. CFB lambs spent more time in active sleep than controls (p=0.02). Frequency of non-nutritive swallowing was not different in CFB and control lambs, whatever the state of alertness. In addition, CFB did not disrupt the overall respiratory-swallowing coordination, inspiratory-related NNS being the most frequent and expiratory-related NNS the least in both CFB and control lambs. Further analyses revealed that CFB had no effect on baseline respiratory and heart rate, and apnea and sigh frequency, whatever the state of alertness. Our results suggest that, in the neonatal period, C-fibers are not involved in NNS frequency and have no influence on the overall respiratory-swallowing coordination.
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Affiliation(s)
- Philippe Reix
- Department of Pediatrics, Université de Lyon, France
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Lanini B, Bianchi R, Romagnoli I, Coli C, Binazzi B, Gigliotti F, Pizzi A, Grippo A, Scano G. Chest wall kinematics in patients with hemiplegia. Am J Respir Crit Care Med 2003; 168:109-13. [PMID: 12714347 DOI: 10.1164/rccm.200207-745oc] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Owing to difficulties in measuring ventilation symmetry, good evidence of different right/left respiratory movements has not yet been provided. We investigated VT differences between paretic and healthy sides during quiet breathing, voluntary hyperventilation, and hypercapnic stimulation in patients with hemiparesis. We studied eight patients with hemiparesis and nine normal sex- and age-matched subjects. Right- and left-sided VT was reconstructed using optoelectronic plethysmography. In control subjects, no asymmetry was found in the study conditions. VTs of paretic and healthy sides were similar during quiet breathing, but paretic VT was lower during voluntary hyperventilation in six patients and higher during hypercapnic stimulation in eight patients (p = 0.02). The ventilatory response to hypercapnic stimulation was higher on the paretic than on the healthy side (p = 0.012). In conclusion, hemiparetic stroke produces asymmetric ventilation with an increase in carbon dioxide sensitivity and a decrease in voluntary ventilation on the paretic side.
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Affiliation(s)
- Barbara Lanini
- Fondazione Don C. Gnocchi (IRCCS), Via Imprunetana, 124 50020 Pozzolatico, Florence, Italy.
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Yamamoto F, Nishino T. Phasic vagal influence on the rate and timing of reflex swallowing. Am J Respir Crit Care Med 2002; 165:1400-3. [PMID: 12016103 DOI: 10.1164/rccm.2108075] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
We investigated the effects of sudden changes in ventilation induced by voluntary hyperpnea and breath-holding on repetitive reflex swallowing elicited by continuous infusion of distilled water into the pharynx in 13 healthy subjects. Ventilation was monitored using a pneumotachograph, and swallowing was identified by submental electromyography with interruption of airflow. We found that voluntary hyperpnea decreased the swallowing frequency whether end-tidal CO(2) tension was maintained at normocapnia or allowed to be hypocapnic. Also, the frequency of swallowing immediately increased with the start of breath-holding, but there was a sudden decrease in swallowing frequency during the hyperpnea observed immediately after the resumption of ventilation (post-breath-holding hyperpnea). The preponderant coupling of swallows with the expiratory phase was lost during voluntary hyperpnea but was maintained during post-breath-holding hyperpnea. These observations may suggest that vagally mediated reflexes are operative in normal physiologic situations and play an important role in the control of swallowing rate as well as in the timing of swallowing in reference to the respiratory cycle.
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Affiliation(s)
- Fumiko Yamamoto
- Department of Anesthesiology, Graduate School of Medicine, Chiba University, Chiba, Japan
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26
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Saito Y, Ezure K, Tanaka I. Swallowing-related activities of respiratory and non-respiratory neurons in the nucleus of solitary tract in the rat. J Physiol 2002; 540:1047-60. [PMID: 11986389 PMCID: PMC2290262 DOI: 10.1113/jphysiol.2001.014985] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Swallowing-related activity was examined in respiratory (n = 60) and non-respiratory (n = 82) neurons that were located in and around the nucleus of the solitary tract (NTS) in decerebrated, neuromuscularly blocked and artificially ventilated rats. Neurons that were orthodromically activated by electrical stimulation of the superior laryngeal nerve (SLN) were identified, and fictive swallowing was evoked by SLN stimulation. The pharyngeal phase of swallowing was monitored by hypoglossal nerve activity. Two types of non-respiratory neurons with swallowing-related bursts were identified: 'early' swallowing neurons (n = 24) fired during periods of hypoglossal bursts, and 'late' swallowing neurons (n = 8) fired after the end of hypoglossal bursts. The remaining non-respiratory neurons were either suppressed (n = 21) or showed no change in activity (n = 29) during swallowing. On the other hand, respiratory neurons with SLN inputs included 56 inspiratory and four expiratory neurons. Inspiratory neurons were classified into two major types: a group of neurons discharged simultaneously with hypoglossal bursts (type 1 neurons, n = 19), while others were silent during bursts but were active during inter-hypoglossal bursts when swallowing was provoked repetitively (type 2 neurons, n = 34). Three of the expiratory neurons fired during hypoglossal bursts. Many of the swallowing-related non-respiratory neurons and the majority of the inspiratory neurons received presumed monosynaptic inputs from the SLN. Details of the distribution and firing patterns of these NTS neurons, which have been revealed for the first time in a fictive swallowing preparation in the rat, suggest their participation in the initiation, pattern formation and mutual inhibition between swallowing and respiration.
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Affiliation(s)
- Yoshiaki Saito
- Department of Neurobiology, Tokyo Metropolitan Institute for Neuroscience, Tokyo Women's Medical University, Japan
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27
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Tobin MJ. Sleep-disordered breathing, control of breathing, respiratory muscles, pulmonary function testing, nitric oxide, and bronchoscopy in AJRCCM 2000. Am J Respir Crit Care Med 2001; 164:1362-75. [PMID: 11704580 DOI: 10.1164/ajrccm.164.8.2108124] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- M J Tobin
- Division of Pulmonary and Critical Care Medicine, Loyola University of Chicago Stritch School of Medicine and Hines Veterans Affairs Hospital, Hines, Illinois 60141, USA.
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