No abstract available.
Dermatomyositis* ; Respiratory Muscles*

BACKGROUND: Pressure support(PS) is becomimg a widely accepted method of mechanical ventilation either for total unloading or for partial unloading of respiratory muscle. The aim of the study was to find out if PS exert different effects on respiratory mechanics in synchronized intermittent mandatory ventilation(SIMV) and continuous positive airway pressure (CPAP) modes. METHODS: 5, 10 and 15 cm H2O of PS were sequentially applied in 14 patients(69+/-12 yrs, M:F=9:5) and respiratory rate (RR), tidal volume(VT), work of breathing(WOB), pressure time product(PTP), P(0.1), and T(1)/T(TOT) were measured using the CP-100 pulmonary monitor(Bicore, USA) in SIMV and CPAP modes respectively. RESULTS: 1) Common effects of PS on respiratory mechanics in both CPAP and SIMV modes As the level of PS was increased(0, 5, 10, 15 cm H2O), VT was increased in CPAP mode(0.28+/-0.09, 0.29+/-0.09, 0.31+/-0.11, 0.34+/-0.12 L, respectively, p=0.001), and also in SIMV mode(0.31+/-0.15, 0.32+/-0.09, 0.34+/-0.16, 0.36+/-0.15 L, respectively, p=0.0215). WOB was decreased in CPAP mode(1.40+/-1.02, 1.01+/-0.80, 0.80+/-0.85, 0.68+/-0.76 joule/L, respectively, p=0.0001), and in SIMV mode(0.97+/-0.77, 0.76+/-0.64, 0.57+/-0.55, 0.49+/-0.49 joule/L, respectively, p=0.0001). PTP was also decreased in CPAP mode(300+/-216, 217+/-165, 179+/-187, 122+/-114cm H2O * sec/min, respectively, p=0.0001), and in SIMV mode(218+/-181, 178+/-157, 130+/-147, 108+/-129cm H2O.sec/min, respectively, p=0.0017). 2) Different effects of PS on respiratory mechanics in CPAP and SIMV modes By application of PS (0, 5, 10, 15 cm H2O), RR was not changed in CPAP mode(27.9+/-6.7, 30.0+/-6.6, 26.1+/-9.1, 27.5+/-5.7/min, respectively, p=0.505), but it was decreased in SIMV mode (27.4+/-5.1, 27.8+/-6.5, 27.6+/-6.2, 25.1+/-5.4/min, respectively, p=0.0001). P(0.1) was reduced in CPAP mode(6.2+/-3.5, 4.8+/-2.8, 4.8+/-3.8, 3.9+/-2.5 cm H2O, respectively, p=0.0061), but not in SIMV mode(4.3+/-2.1, 4.0+/-1.8, 3.5+/-1.6, 3.5+/-1.9 cm H2O, respectively, p=0.054). T(1)/T(TOT) was decreased in CPAP mode(0.40+/-0.05, 0.39+/-0.04, 0.37+/-0.04, 0.35+/-0.04, respectively, p=0.0004), but not in SIMV mode(0.40+/-0.08, 0.35+/-0.07, 0.38+/-0.10, 0.37+/-0.10, respectively, p=0.287). 3) Comparison of respiratory mechanics between CPAP+PS and SIMV alone at same tidal volume. The tidal volume in CPAP+PS 10 cm H2O was comparable to that of SIMV alone. Under this condition, the RR(26.1+/-9.1, 27.4+/-5.1/min, respectively, p=0.516), WOB(0.80+/-0.85, 0.97+0.77 joule/L, respectively, p=0.485), P0.1(3.9+/-2.5, 4.3+/-2.1 cm H2O, respectively, p=0.481) were not different between the two methods, but PTP(179+/-187, 218+/-181 cmH2O.sec/min, respectively, p=0.042) and T(1)/T(TOT)(0.37+/-0.04, 0.40+/-0.08, respectively, p=0.026) were significantly lower in CPAP+PS than in SIMV alone. CONCLUSION: PS up to 15 cm H2O increased tidal volume, decreased work of breathing and pressure time product in both SIMV and CPAP modes. PS decreased respiration rate in SIMV mode but not in CPAP mode, while it reduced central respiratory drive(P(0.1)) and shortened duty cycle (T(1)/T(TOT)) in CPAP mode but not in SIMV mode. By 10 cm H2O of PS in CPAP mode, same tidal volume was obtained as in SIMV mode, and both methods were comparable in respect to RR, WOB, P(0.1), but CPAP+PS was superior in respect to the efficiency of the respiratory muscle work (PTP) and duty cycle(T(1)/T(TOT)).
Continuous Positive Airway Pressure ; Respiration, Artificial ; Respiratory Mechanics* ; Respiratory Muscles ; Respiratory Rate ; Tidal Volume ; Work of Breathing

PURPOSE: To assess the ability of a mechanical in-exsufflator (MI-E), either alone or in combination with manual thrust, to augment cough in patients with neuromuscular disease (NMD) and respiratory muscle dysfunction. MATERIALS AND METHODS: For this randomized crossover single-center controlled trial, patients with noninvasive ventilator-dependent NMD were recruited. The primary outcome was peak cough flow (PCF), which was measured in each patient after a cough that was unassisted, manually assisted following a maximum insufflation capacity (MIC) maneuver, assisted by MI-E, or assisted by manual thrust plus MI-E. The cough augmentation techniques were provided in random order. PCF was measured using a new device, the Cough Aid. RESULTS: All 40 enrolled participants (37 males, three females; average age, 20.9±7.2 years) completed the study. The mean (standard deviation) PCFs in the unassisted, manually assisted following an MIC maneuver, MI-E-assisted, and manual thrust plus MI-E-assisted conditions were 95.7 (40.5), 155.9 (53.1), 177.2 (33.9), and 202.4 (46.6) L/min, respectively. All three interventions significantly improved PCF. However, manual assistance following an MIC maneuver was significantly less effective than MI-E alone. Manual thrust plus MI-E was significantly more effective than both of these interventions. CONCLUSION: In patients with NMD and respiratory muscle dysfunction, MI-E alone was more effective than manual assistance following an MIC maneuver. However, MI-E used in conjunction with manual thrust improved PCF even further.
Cough* ; Female ; Humans ; Insufflation ; Male ; Neuromuscular Diseases ; Respiratory Muscles*

PURPOSE: To assess the ability of a mechanical in-exsufflator (MI-E), either alone or in combination with manual thrust, to augment cough in patients with neuromuscular disease (NMD) and respiratory muscle dysfunction. MATERIALS AND METHODS: For this randomized crossover single-center controlled trial, patients with noninvasive ventilator-dependent NMD were recruited. The primary outcome was peak cough flow (PCF), which was measured in each patient after a cough that was unassisted, manually assisted following a maximum insufflation capacity (MIC) maneuver, assisted by MI-E, or assisted by manual thrust plus MI-E. The cough augmentation techniques were provided in random order. PCF was measured using a new device, the Cough Aid. RESULTS: All 40 enrolled participants (37 males, three females; average age, 20.9±7.2 years) completed the study. The mean (standard deviation) PCFs in the unassisted, manually assisted following an MIC maneuver, MI-E-assisted, and manual thrust plus MI-E-assisted conditions were 95.7 (40.5), 155.9 (53.1), 177.2 (33.9), and 202.4 (46.6) L/min, respectively. All three interventions significantly improved PCF. However, manual assistance following an MIC maneuver was significantly less effective than MI-E alone. Manual thrust plus MI-E was significantly more effective than both of these interventions. CONCLUSION: In patients with NMD and respiratory muscle dysfunction, MI-E alone was more effective than manual assistance following an MIC maneuver. However, MI-E used in conjunction with manual thrust improved PCF even further.
Cough* ; Female ; Humans ; Insufflation ; Male ; Neuromuscular Diseases ; Respiratory Muscles*

Myasthenia gravis is a rare disease entity in Korea, and its occurrence with a thymoma is even rarer. Myasthenia gravis has offered many difficult problems for the anesthesiologist because it affects respiratory muscles frequently and perioperative management of these patients is difficult. The authors aensthetized a patient with myasthenia gravis and thymoma. We report this experience with a brief literature review.
Humans ; Korea ; Myasthenia Gravis* ; Rare Diseases ; Respiratory Muscles ; Thymoma*

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*

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

BACKGROUND: Organophosphate poisoning is one of the most common toxicologic emergencies in Korea. Acute organophosphate poisoning and delayed polyneuropathy by ingestion are well published. There have been several reports about intermediate syndrome in organophosphate poisoning by ingestion but few about intermediate syndrome via dermal route. CASE REPORT: We observed a 59-years-old male who had weakness of proximal limb muscles and respiratory muscles 2 days after dermal exposure by unidentified pesticide. The paralytic symptoms lasted up to 20 days but the delayed polyneuropathy did not develop. The patient needed mechanical ventilatory support for 2 weeks and had completely recovered from IMS 6 weeks later. Electrophysiological study was characterized by an axonal polyneuropathy pattern on the proximal limb muscles. Serum acetylcholinesterase level was below half of normal level. Clinical manifestations and electrophysiological study support the clinical diagnosis of intermediate syndrome. CONCLUSION: Intermediate syndrome is commonly developed by ingestion of organophosphate but, as in this case, dermal absorption can also lead to intermediate syndrome. More detailed history taking and close observation is needed for about 3 or more days after intoxication because of the risk of respiratory failure.
Absorption ; Acetylcholinesterase ; Axons ; Diagnosis ; Eating ; Emergencies ; Extremities ; Humans ; Korea ; Male ; Muscles ; Organophosphate Poisoning* ; Polyneuropathies ; Respiratory Insufficiency ; Respiratory Muscles

It is said that respiratory failure as an initial manifestation is extremely rare in adult polymyositis. Respiratory failure has been reported in the terminal stage of polymyositis and usually unresponsive to steroid therapy. We experienced two cases of polymyositis presenting with respiratory failure at onset due to respiratory muscle weakness. On admission they had only short history of increasing dyspnea and mild limb weakness before respiratory failure. Diagnosis of polymyositis was established by muscle enzyme, electromyography and muscle biopsy. Oral steroid therapy was initiated with assisted ventilation which resulted in good recovery. Although respiratory failure due to preferential respiratory muscle involvement is very rare, polymyositis should be considered as one of underlying diseases causing severe respiratory failure.
Adult ; Biopsy ; Diagnosis ; Dyspnea ; Electromyography ; Extremities ; Humans ; Polymyositis* ; Respiratory Insufficiency* ; Respiratory Muscles ; Ventilation

Respiratory pump failure is a condition which the respiratory system can not meet the metabolic demand because of the inability of respiratory muscles to ventilate the lungs without any pulmonary pathology. Two cases of respiratory pump failure(myasthenia gravis and Guillian-Barre syndrome) had been treated with controlled and assisted ventilation using the Bennet MA II ventilator. Large tidal volume with high peak flow rate was given to permit leakage of gases during inspiration when the patients were ventilated with CMV with asaistance. This made the patients capable of communicating with persons by phonation which was the greatest advanage of this mode of assisted ventilation.
Gases ; Humans ; Lung ; Pathology ; Phonation ; Respiratory Muscles ; Respiratory System ; Tidal Volume ; Ventilation ; Ventilators, Mechanical