In order to accurately capture the respiratory muscle movement and extract the synchronization signals corresponding to the breathing phases, a comprehensive signal sensing system for sensing the movement of the respiratory muscle was developed with applying the thin-film varistor FSR402 IMS-C07A in this paper. The system integrated a sensor, a signal processing circuit, and an application program to collect, amplify and denoise electronic signals. Based on the respiratory muscle movement sensor and a STM32F107 development board, an experimental platform was designed to conduct experiments. The respiratory muscle movement data and respiratory airflow data were collected from 3 healthy adults for comparative analysis. In this paper, the results demonstrated that the method for determining respiratory phase based on the sensing the respiratory muscle movement exhibited strong real-time performance. Compared to traditional airflow-based respiratory phase detection, the proposed method showed a lead times ranging from 33 to 210 ms [(88.3 ± 47.9) ms] for expiration switched into inspiration and 17 to 222 ms [(92.9 ± 63.8) ms] for inspiration switched into expiration, respectively. When this system is applied to trigger the output of the ventilator, it will effectively improve the patient-ventilator synchrony and facilitate the ventilation treatment for patients with respiratory diseases.
Humans ; Respiratory Muscles/physiology* ; Signal Processing, Computer-Assisted ; Movement/physiology* ; Respiration ; Monitoring, Physiologic/methods* ; Adult

Mechanical ventilation has, since its introduction into clinical practice, undergone a major evolution from controlled ventilation to diverse modes of assisted ventilation. Conventional mechanical ventilators depend on flow sensors and pneumatic pressure and controllers to complete the respiratory cycle. Neurally adjusted ventilatory assist (NAVA) is a new form of assisted ventilation in recent years, which monitors the electrical activity of the diaphragm (EAdi) to provide an appropriately level of pressure support. And EAdi is the best available signal to sense central respiratory drive and trigger ventilatory assist. Unlike other ventilation modes, NAVA breathing instructions come from the center. Therefore, NAVA have the synchronous nature of the breaths and the patient-adjusted nature of the support. Compared with traditional ventilation mode, NAVA can efficiently unload respiratory muscles, relieve the risk of ventilator-induced lung injury (VILI), improve patient-ventilator coordination, enhance gas exchange, increase the success rate of weaning, etc. This article reviews the research progress of NAVA in order to provide theoretical guidance for clinical applications.
Humans ; Interactive Ventilatory Support ; Respiration, Artificial ; Positive-Pressure Respiration ; Diaphragm/physiology* ; Respiratory Muscles/physiology*

OBJECTIVE: To evaluate the feasibility and safety of Liuzijue exercise (LE) for the clinical effect in patients after cardiac surgery. METHODS: Totally 120 patients who underwent cardiac surgery and were admitted to the Cardiothoracic Intensive Care Unit of Nanjing Drum Tower Hospital between July and Oclober, 2022 were allocated to the LE group, the conventional respiratory training (CRT) group, and the control group by a random number table at a ratio of 1:1:1; 40 patients in each group. All patients received routine treatment and cardiac rehabilitation. LE group and CRT group respectively performed LE and CRT once a day for 30 min for 7 days. Control group did not receive specialized respiratory training. The forced vital capacity, forced expiratory volume in 1 s, peak inspiratory flow rate, peak expiratory flow rate, maximum inspiratory pressure, maximum expiratory pressure, modified Barthel index (MBI), and Hamilton Rating Scale for Anxiety (HAM-A) were evaluated before, after 3 and 7 days of intervention. In addition, the postoperative length of hospital stay (LOS) and the adverse events that occurred during the intervention period were compared. RESULTS: A total of 107 patients completed the study, 120 patients were included in the analysis. After 3 days of intervention, the pulmonary function, respiratory muscle strength, MBI and HAM-A of all 3 groups improved compared with that before the intervention (P<0.05 or P<0.01). Compared with the control group, pulmonary function and respiratory muscle strength were significantly improved in the CRT and LE groups (P<0.05 or P<0.01). MBI and HAM-A were significantly improved in the LE group compared with the control and CRT groups (P<0.05 or P<0.01). On the 7th day after intervention, the difference was still statistically significant (P<0.01), and was significantly different from that on the 3rd day (P<0.05 or P<0.01). In addition, on the 7th day of intervention, the pulmonary function and respiratory muscle strength in the LE group were significantly improved compared with those in the CRT group (P<0.01). MBI and HAM-A were significantly improved in the CRT group compared with the control group (P<0.01). There were no significant differences in postoperative LOS among the 3 groups (P>0.05). No training-related adverse events occurred during the intervention period. CONCLUSIONS LE is safe and feasible for improving pulmonary function, respiratory muscle strength, the ability to complete activities of daily living and for relieving anxiety of patients after cardiac surgery (Registration No. ChiCTR2200062964).
Humans ; Activities of Daily Living ; Breathing Exercises ; Cardiac Surgical Procedures/adverse effects* ; Respiratory Muscles ; Muscle Strength/physiology*

Mechanical ventilation (MV) is an effective treatment for respiratory failure. In recent years, it has been found that MV can not only cause ventilation-associated lung injury (VALI), but also cause ventilation-induced diaphragmatic dysfunction (VIDD). Although the injury site and etiology are not the same, they are interrelated and mutually causal, and eventually lead to weaning failure. Studies have indicated that diaphragmatic function protection strategy should be implemented in patients on MV. That is, the entire process from assessing the ability of spontaneous breathing before MV, to the initiation of spontaneous breathing and to weaning during MV. For patients on MV, continuous monitoring of respiratory muscle strength should be conducted. Early prevention, early intervention and timely detection of VIDD may reduce the occurrence of difficult weaning, resulting in improved prognosis. This study mainly discussed the risk factors and pathogenesis of VIDD.
Humans ; Respiration, Artificial ; Respiratory Muscles ; Respiration ; Diaphragm ; Cognition

Central hypoventilation syndrome is a rare and fatal condition resulting from various central nervous system disorders that is characterized by a failure of automatic breathing. We report a case of central hypoventilation syndrome following posterior circulation stroke whose pulmonary function was improved by respiratory rehabilitation. A 59-year-old woman with a history of hemorrhagic stroke of the bilateral cerebellum was hospitalized due to pneumonia. A portable ventilator was applied via tracheostomy, recurrent episodes of apnea and hypercapnia impeded weaning. A respiratory rehabilitation program including chest wall range of motion exercise, air stacking exercise, neuromuscular electrical stimulation (NMES) on abdominal muscles, upper extremity ergometer, locomotor training, high-frequency chest wall oscillator, mechanical insufflation, and exsufflation was employed, as spirometry showed a severe restrictive pattern. A spontaneous breathing trial was started, and a portable ventilator was applied for 8 hours, only during nighttime, to prevent sudden apneic event. After 4 weeks of treatment, follow-up spirometry showed much improved respiratory parameters. This case suggests that respiratory rehabilitation can improve pulmonary function parameters and quality of life in central hypoventilation syndrome.
Abdominal Muscles ; Apnea ; Central Nervous System Diseases ; Cerebellum ; Electric Stimulation ; Female ; Follow-Up Studies ; Humans ; Hypercapnia ; Hypoventilation ; Insufflation ; Middle Aged ; Pneumonia ; Quality of Life ; Range of Motion, Articular ; Rehabilitation ; Respiration ; Respiratory Center ; Spirometry ; Stroke ; Thoracic Wall ; Tracheostomy ; Upper Extremity ; Ventilators, Mechanical ; Weaning

PURPOSE: Changes in the curvature of the vertebral columns of elderly women with increasing age causes various side effects and disorders. Therefore, this study was conducted to evaluate the effectiveness of the 8-figure scapular brace to improve pulmonary function and balance ability based on lung capacity and foot pressure by increasing the vertebral curvature. METHODS: Seventeen elderly women with a forward head posture were selected. Women were asked to wear the 8-figure scapular brace and the forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) were measured, as were changes in foot pressure. Measurements were conducted three times each and the mean values were used for subsequent analyses. For static evaluation, we used the paired t-test to identify differences between pre and post values. RESULTS: There was no significant difference in FEV1 and FVC before and after use of the brace (p>0.05); however, there was a significant decrease in forefoot pressure and an increase in rearfoot pressure following application of the brace (p < 0.05). CONCLUSION: Application of the 8-figure scapular brace to correct vertebral curvature in elderly women influenced pressure distribution change from immediate effect body arrange of cervical and thoracic. However, wearing the 8-figure scapular brace may interfere with expansion of the chest and therefore respiratory muscle activity. Accordingly, it is necessary to apply appropriate treatment when wearing a scapular brace and to allow a sufficient intervention period while also providing therapeutic interventions such as posture correction or respiration training.
Aged* ; Braces* ; Female ; Foot* ; Forced Expiratory Volume ; Head* ; Humans ; Lung Volume Measurements ; Posture* ; Respiration ; Respiratory Muscles ; Spine ; Thorax ; Vital Capacity

PURPOSE: Frequent desaturation due to immature incoordination of suck-swallow-breathing in preterm infants can influence multiple organs such as the heart, lungs, and brain, which can then affect growth and development. Most notably in preterm infants, feeding desaturation may even affect pulmonary function during gavage feeding. Because respiratory muscle activities may reflect the work required during respiration, we evaluated the differences in these activities between full-term and preterm infants with feeding desaturation, and investigated the correlations with clinical variables. METHODS: Nineteen preterm infants with feeding desaturation (group 1) and 19 age-matched full-term infants (group 2) were evaluated. Oromotor function was evaluated using video recording. The root-mean-squre (RMS) envelope of the electromyography signal was calculated to quantify the activities of muscles involved in respiration. The differences in RMS between both groups and the correlation with clinical variables including gestational age (GA), birth weight (BW), and Apgar scores (AS) at 1 and 5 minutes after birth were evaluated. RESULTS: The RMS values of the diaphragm (RMS-D) and rectus abdominis (RMS-R) were significantly greater in group 1 compared to group 2, and the 1- and 5-min AS were significantly lower in group 1 compared to group 2. RMS-D and RMS-R were inversely correlated with GA, BW, 1- and 5-min AS in all infants. CONCLUSION: This study showed that respiratory muscle activities were augmented during feeding in preterm infants compared to full-term infants. Additionally, respiratory muscle activities were inversely correlated with all clinical variables.
Ataxia ; Birth Weight ; Brain ; Diaphragm ; Electromyography ; Gestational Age ; Growth and Development ; Heart ; Humans ; Infant ; Infant, Newborn ; Infant, Premature* ; Lung ; Muscles ; Parturition ; Rectus Abdominis ; Respiration ; Respiratory Muscles* ; Video Recording

PURPOSE: This study evaluated the effects of respiratory muscle training on respiratory function, balance, and activities of daily living (ADL) in patients with stroke. METHODS: The study included 21 patients with stroke, divided into the experimental group and control group. Both groups underwent traditional physical therapy once a day for 30 minutes, five times weekly for 6 weeks. The experimental group underwent additional respiratory muscle training once a day, five times a week during the study period. Maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), Berg balance scale (BBS), and Korean-modified Barthel index (K-MBI) were measured before and after the study period. For statistical analysis, paired t-test was used to compare the difference between the pre and post values. Independent t-test was used compare the differences between groups. RESULTS: Both groups had significantly improved MIP, MEP, BBS, and K-MBI scores after the study period. The experimental group had significantly improved MIP, MEP, BBS, and K-MBI scores. CONCLUSION: These results suggest that respiratory muscle training improves respiratory function, balance, and ADL in patients with stroke.
Activities of Daily Living* ; Breathing Exercises* ; Humans ; Respiratory Muscles* ; Stroke*

Management of mechanical ventilation is essential for patients with neuro-critical illnesses who may also have impairment of airways, lungs, respiratory muscles, and respiratory drive. However, balancing the approach to mechanical ventilation in the intensive care unit (ICU) with the need to prevent additional lung and brain injury, is challenging to intensivists. Lung protective ventilation strategies should be modified and applied to neuro-critically ill patients to maintain normocapnia and proper positive end expiratory pressure in the setting of neurological closed monitoring. Understanding the various parameters and graphic waveforms of the mechanical ventilator can provide information about the respiratory target, including appropriate tidal volume, airway pressure, and synchrony between patient and ventilator, especially in patients with neurological dysfunction due to irregularity of spontaneous respiration. Several types of asynchrony occur during mechanical ventilation, including trigger, flow, and termination asynchrony. This review aims to present the basic interpretation of mechanical ventilator waveforms and utilization of waveforms in various clinical situations in the neuro-ICU.
Brain Injuries ; Humans ; Intensive Care Units ; Lung ; Positive-Pressure Respiration ; Respiration ; Respiration, Artificial ; Respiratory Muscles ; Tidal Volume ; Ventilation ; Ventilator-Induced Lung Injury ; Ventilators, Mechanical

Pulseless electrical activity (PEA) is a clinical condition characterized by unresponsiveness and lack of palpable pulse in the presence of organized cardiac electrical activity and is caused by a profound cardiovascular insult (e.g., severe prolonged hypoxia or acidosis, extreme hypovolemia, or flow-restricting pulmonary embolus). Amyotrophic lateral sclerosis (ALS) is a disease that is characterized by progressive degeneration of all levels of the motor nervous system. Damage to the respiratory system and weakness of the muscles may increase the likelihood of an emergency situation occurring in patients with ALS while under general anesthesia. We report a case of PEA during the induction of general anesthesia in a patient with ALS who presented for dental treatment and discuss the causes of PEA and necessary considerations for general anesthesia in patients with ALS.
Acidosis ; Amyotrophic Lateral Sclerosis* ; Anesthesia, General* ; Anoxia ; Emergencies ; Humans ; Hypovolemia ; Muscles ; Nervous System ; Peas ; Respiratory System