• Tuberculosis and Respiratory Diseases
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• v.67 no.1
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• pp.21-26
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• 2009

Background: Non-invasive positive pressure ventilation (NPPV) ensures adequate gas exchange during bronchoscopy in spontaneously breathing, hypoxemic patients, thus avoiding endotracheal intubation. However, in some patients, endotracheal intubation is eventually required after bronchoscopy. This study investigated the incidence of intubation and predictors of a need for emergency intubation prior to NPPV bronchoscopy initiation. Methods: On a retrospective basis, we reviewed the medical records of 36 patients (median age, 55 years; interquartile range [IQR], 43~65 years) with acute hypoxemic respiratory failure who required NPPV during bronchoscopy between January 2005 and October 2007. Results: All patients were hypoxemic (median $PaO_2/FiO_2$ ratio 155; IQR 90~190), but tolerated bronchoscopy with NPPV support. SOFA score and SAPS II score immediately before NPPV initiation were 4 (3~7) and 36 (30~42), respectively. Seventeen (47%) patients needed endotracheal intubation at a median time of 22 (2~50) hours after bronchoscopy. Patients who needed intubation after bronchoscopy had a higher in-hospital mortality (11 [65%] vs. 4 [21%], p=0.017). Upon multiple logistic regression analysis, the need for intubation after bronchoscopy was independently associated with a $P_aO_2/FiO_2$ ratio (OR, 0.961; 95% CI, 0.924~0.999; p=0.047) immediately before NPPV initiation for bronchoscopy. Conclusion: The severity of the hypoxemia immediately prior to NPPV initiation for bronchoscopy was associated with the need for intubation after bronchoscopy in patients with hypoxemic respiratory failure.

• Tuberculosis and Respiratory Diseases
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• v.52 no.1
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• pp.14-23
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• 2002

Background: The opitmal ventilator setting during partial liquid ventilation(PLV) is controversial. This study investigated the effects of various gas exchange parameters during PLV in normal rabbit lungs in order to aid in the development of an optimal ventilator setting during PLV. Methods: Seven New-Zealand white rabbits were ventilated in pressure-controlled mode with the following settings; tidal volume($V_T$) 8 mL/kg, positive end-expiratory pressure(PEEP) 4 $cmH_2O$, inspiratory-to-expiratory ratio(I:E ratio) 1:2, fraction of inspired oxygen($F_TO_2$) 1.0. The respiration rate(RR) was adjusted to keep $PaCO_2$ between 35~45 mmHg. The ventilator settings were changed every 30 min in the following sequence : (1) Baseline, as the basal ventilator setting, (2) Inverse ratio, I:E ratio 2:1, (3) high PEEP, adjust PEEP to achieve the same mean inspiratory pressure (MIP) as in the inverse ratio, (4) High $V_T$, $V_T$ 15 mL/kg, (5) high RR, the same minute ventilation (MV) as in the High $V_T$. Subsequently, the same protocol was repeated after instilling 18 mL/kg of perfluorodecalin for PLV. The parameters of gas exchange, lung mechanics, and hemodynamics were examined. Results: (1) The gas ventilation(GV) group showed no significant changes in the $PaO_2$ at all phases. The $PaCO_2$ was lower and the pH was higher at the high $V_T$ and high RR phases(p<0.05). No significant changes in the lung mechanics and hemodynamics parameters were observed. (2) The baseline $PaO_2$ for the PLV was $312{\pm}$ mmHg. This was significantly lower when decreased compared to the baseline $PaO_2$ for GV which was $504{\pm}81$ mmHg(p=0.001). During PLV, the $PaO_2$, was significantly higher at the high PEEP($452{\pm}38$ mmHg) and high $V_T$ ($461{\pm}53$ mmHg) phases compared with the baseline phase. However, it did not change significantly during the inverse I:E ratio or the high RR phases. (3) The $PaCO_2$ was significantly lower at high $V_T$ and RR phases for both the GV and PLV. During the PLV, $PaCO_2$ were significantly higher compared to the GV (p<0.05). (4) There were no important or significant changes in of baseline and high RR phases lung mechanics and hemodynamics parameters during the PLV. Conclusion: During PLV in the normal lung, adequate $V_T$ and PEEP are important for optimal oxygenation.

• Korean Journal of Exercise Nutrition
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• v.25 no.1
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• pp.1-6
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• 2021

[Purpose] We determined the effect of partial sleep deprivation (PSD) after an exercise session on exercise performance on the following morning. [Methods] Eleven male athletes performed either a normal sleep trial (CON) or a PSD trial. On the first day (day 1), all subjects performed an exercise session consisting of 90 min of running (at 75% ${\dot{V}}O_{2max}$) followed by 100 drop jumps. Maximal strength (MVC) was evaluated before and after exercise. In the CON trial, the sleep duration was 23:00-7:00, while in the PSD trial, the sleep duration was shortened to 40% of the regular sleep duration. On the following morning (day 2), MVC, the metabolic responses during 20 min of running (at 75% ${\dot{V}}O_{2max}$), and time to exhaustion (TTE) at 85% ${\dot{V}}O_{2max}$ were evaluated. [Results] On day 2, neither the MVC nor ${\dot{V}}O_2$ during 20 min of running differed significantly between the two trials. However, the respiratory exchange ratio was significantly lower in the PSD trial than in the CON trial (p = 0.01). Moreover, the TTE was significantly shorter in the PSD trial than in the CON trial (p = 0.01). [Conclusion] A single night of PSD after an exercise session significantly decreased endurance performance without significantly changing muscle strength or cardiopulmonary response.

• Tuberculosis and Respiratory Diseases
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• v.63 no.5
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• pp.423-429
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• 2007

Background: Alveolar recruitment (RM) is one of the primary goals of respiratory care for an acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). The purposes of alveolar recruitment are an improvement in pulmonary gas exchange and the protection of atelectrauma. This study examined the effect and safety of the alveolar RM using pressure control ventilation (PCV) in early ALI and ARDS patients. Methods: Sixteen patients with early ALI and ARDS who underwent alveolar RM using PCV were enrolled in this study. The patients data were recorded at the baseline, and 20 minutes, and 60 minutes after alveolar RM, and on the next day after the maneuver. Alveolar RM was performed with an inspiratory pressure of $30cmH_2O$ and a PEEP of $20cmH_2O$ in a 2-minute PCV mode. The venous $O_2$ saturation, central venous pressure, blood pressure, pulse rate, $PaO_2/FiO_2$ ratio, PEEP, and chest X-ray findings were obtained before and after alveolar RM. Results: Of the 16 patients, 3 had extra-pulmonary ALI/ARDS and the remaining 13 had pulmonary ALI/ARDS. The mean PEEP was 11.3 mmHg, and the mean $PaO_2/FiO_2$ ratio was 130.3 before RM. The $PaO_2/FiO_2$ ratio increased by 45% after alveolar RM. The $PaO_2/FiO_2$ ratio reached a peak 60 minutes after alveolar RM. The Pa$CO_2$ increased by 51.9 mmHg after alveolar RM. The mean blood pressure was not affected by alveolar RM. There were no complications due to pressure injuries such as a pneumothorax, pneumomediastinum, and subcutaneous emphysema. Conclusion: In this study, alveolar RM using PCV improved the level of oxygenation in patients with an acute lung injury and acute respiratory distress syndrome. Moreover, there were no significant complications due to hemodynamic changes and pressure injuries. Therefore, alveolar RM using PCV can be applied easily and safely in clinical practice with lung protective strategy in early ALI and ARDS patients.

• Preventive Nutrition and Food Science
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• v.14 no.3
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• pp.173-178
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• 2009

This study was conducted to determine if supplementation with a compound composed of caffeine (50 mg), capsaicin (75 mg), sesamine (30 mg), L-carnitine (300 mg), banaba (50 mg) and lotus (10 mg) enhanced human autonomic nervous activities (ANS) associated with thermogenic sympathetic activity and fat utilization. Ten healthy college males (21.2$\pm$1.0 yr) volunteered for this experiment. Autonomic nervous activities associated with energy metabolism were examined at 30 min intervals for a total of 120-min while at rest and every 5-min during exercise at 50% of the ventilation threshold before and after intake of the compound or placebo with 100 ml of water for 10 days. In addition, heart rate variability power spectral analysis was used to assess human autonomic nervous activities. The results indicated that there were no significant differences in heart rate during rest and exercise among trials. Furthermore, the autonomic nervous activity tended to increase after 10-days of consumption of the test compounds during the experimental period, but the differences did not reach statistical significance. However, before and after the compound test trial there was a significantly higher respiratory gas exchange ratio (rest 0: 0.83$\pm$0.01 vs. rest 3: 0.89$\pm$0.02, p<0.05), carbohydrate oxidation (CHO) rate (rest 0: 44.57$\pm$5.83 vs. rest 2: 63.86$\pm$5.91%, p<0.05) and a lower fat oxidation rate (rest 0: 55.43$\pm$5.83 vs. rest 2: 36.14$\pm$5.91%, p<0.05. In conclusion, the results of the present study suggested that the compound composed of caffeine, capsaicin, sesamine, L-carnitine, banaba and lotus components that was evaluated in this study did not induce a significant increase in human autonomic nervous activities or lipolysis, even though the individual components have been reported to induce increased fat oxidation.

• Journal of Practical Engineering Education
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• v.6 no.1
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• pp.1-7
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• 2014

The variable control in the inductive inference for the confirmation and verification when the experimental data are collected is studied by applying the principle of probability inference. The control in engineering experiments is to protect any effect by of intervening variable except primary independent variable on the dependent variable. By the special condition the possibility for developing a phenomenon will be maximized; otherwise, by the extraneous condition the possibility for developing a phenomenon will be minimized. By doing so, the control may provide insurance for the causal relationship between the certain prior event (independent variable) and the post-event (the dependent variable). Some experiments by using both elliptical trainer and tread mill under the variable control are performed in order to find the relations between the energy expenditure, the respiratory exchange ratio (RER), and the heart rate (HR) against the exercise speed.

• Advances in Traditional Medicine
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• v.4 no.1
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• pp.18-21
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• 2004

Six volunteers (mean $age=25.7{\pm}1.7$, $height=173{\pm}1.9$ and $weight=63.4{\pm}2.3{\;}kg$) participated in a graded exercise test and one hour of basic form of ChunDoSunBup (CDSB) Qi-training to investigate the cardiorespiratory responses and exercise intensity of Qi-training, a Korean traditional psychosomatic training. In the maximal exercise, the trainee showed $96.2{\pm}8.89{\;}l/min$ in ventilation (VE), $46.0{\pm}4.4$ in breath frequency (BF), $1.31{\pm}0.05$ in respiratory exchange ratio (RER), $180.7{\pm}3.0$ in heart rate (HR), and $2.6{\pm}1.1{\;}l/min$ or $40.7{\pm}2.3{\;}ml/kg/ml$ in oxygen consumption $(VO_2)$. Qi-training induced significant changes in BF, RER, HR, and $VO_2$. The exercise intensity of Qi-training were 42.3%, 46.9% and 38.7% of $HR_{max}$ during the sound exercise, slow motion (haeng-gong) and meditation respectively and the average was 46.2% of $HR_{max}$. We conclude that Qi-training is an aerobic exercise of a light (mild) intensity exercise, and it leads to decrease the metabolic rate in the trainee by breathing efficiently and relaxing them. In addition, Qi-training may affect cardiorespiratory function of BF, RER, HR and $VO_{2max}$ in trainees.

• The Journal of Korean Physical Therapy
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• v.31 no.5
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• pp.322-327
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• 2019

Purpose: This study examined the influence of the maximal aerobic capacity on the two-year cardiac-related re-hospitalization in patients with heart failure with a reduced ejection fraction (HFrEF) in Korean society. Methods: The maximal aerobic capacity of the study population (n=95, male 63%) was evaluated using a cardiopulmonary exercise (CPX) testing system. Each patient was followed up for two years to divide the HFrEF patients into two groups according to cardiac-related re-hospitalization: re-hospitalization (RH) group (n=29, 30%) and no re-hospitalization (NRH) group (n=66, 70%). Results: The relative peak $VO_2$ (mL/kg/min, p<0.001), exercise duration (p<0.001), respiratory exchange ratio ($VCO_2/VO_2$, p=0.001), systolic blood pressure (SBP) reserve (p=0.004), heart rate (HR) reserve (p=0.007), SBP max (p=0.02), and HR max (p=0.039) were significantly lower in the RH group than the NRH group during the CPX test. On the other hand, the ventilatory efficiency (VE/VCO2 slope, p=0.02) and age (p=0.022) were significantly higher in the RH group than in the NRH group. In binary logistic regression analysis, the relative peak $VO_2$ (p=0.001, Wald Chi-square 10.137) was the strongest predictive factor on cardiac-related re-hospitalization, which was followed by $VCO_2/VO_2$ (p=0.019, Wald Chi-square 5.54). On the other hand, age (p=0.063, Wald Chi-square 3.445) did not have a significant influence on cardiac related re-hospitalization. Conclusion: The maximal aerobic capacity, especially the relative peak $VO_2$, is the strongest factor on cardiac-related re-hospitalization within two years in patients with HFrEF in Korean society.

• Biomedical Science Letters
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• v.19 no.3
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• pp.254-260
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• 2013

The purpose of this study was to survey the effects of Karvonen exercise prescription in coronary artery disease patients reaching age-predicted maximal heart rates with the exercise stress test on hemodynamic responses and cardiorespiratory fitness. The subject group was comprised of acute coronary syndrome (ACS) patients, who were divided into the maximal heart rate (MHR) group that included those who completed the test with their heart rates reaching the number of 220-age and the maximal dyspnea (MD) group that included those who could not continue the test due to respiratory difficulty and were asked to stop the test. Both groups had the exercise stress test before and after the experiment. In the exercise stress test before the experiment, the exercise prescription intensity of Karvonen was set at the target heart rates of 50~85% with a six-week exercise monitoring arrangement. As a result, there were no interactive effects in rest heart rate (RHR) according to time and group, but interactive effects were observed in maximal heart rate (MHR) (P=0.000). Both rest systolic blood pressure (RSBP) and rest diastolic blood pressure (RDBP) had no interactive effects according to time and group. Maximal systolic blood pressure (MSBP) showed significant interactive effects according to time and group (P=0.017). Maximal diastolic blood pressure (MDBP) showed no interactive effects according to time and group, while maximal rate pressure product (MRPP) showed significant interactive effects according to time and group (P=0.003). Maximal time (MT) had no interactive effects according to time and group. $VO_{2max}$ and maximal metabolic equivalent (MMET) showed significant interactive effects according to time and group (P=0.000, P=0.002, respectively), whereas maximal respiratory exchange ratio (MRER) and maximal rating of perceived exertion (MRPE) showed no interactive effects according to time and group. The exercise test that was discontinued as the subjects reached the predicted maximal heart rates considering age did not reach the maximal exercise intensity and accordingly showed low exercise effects when applied to Karvonen exercise prescription intensity. That is, the test should keep going by monitoring cardiac events, MRER and MRPE until the heart rates exceed the predicted MHR by up to 10~12 even after the subject reaches the predicted MHR considering age in the exercise stress test.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.6
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• pp.851-858
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• 2018

Objective: This study was conducted to compare different methods on effective energy evaluation of corn silage for beef cattle. Methods: Twenty Wandong bulls (Chinese indigenous yellow cattle) with initial body weight of $281{\pm}15.6kg$, were assigned to 1 of 5 dietary treatments with 4 animals per treatment in a randomized complete block design. Five dietary treatments included group 1 with corn silage only diet, group 2 with corn silage-concentrate basal diet (BD) and 3 groups with 3 test diets, which were the BD partly substituted by corn silage at 10%, 30%, and 60%. The total collection digestion trial was conducted for 5 d for each block after a 10-d adaptation period, and then an open-circuit respiratory cage was used to measure the gas exchange of each animal in a consecutive 4-d period. Results: The direct method-derived metabolizable energy and net energy of corn silage were 8.86 and 5.15 MJ/kg dry matter (DM), expressed as net energy requirement for maintenance and gain were 5.28 and 2.90 MJ/kg DM, respectively; the corresponding regression method-derived estimates were 8.96, 5.34, 5.37, and 2.98 MJ/kg DM, respectively. The direct method-derived estimates were not different (p>0.05) from those obtained using the regression method. Using substitution method, the nutrient apparent digestibility and effective energy values of corn silage varied with the increased corn silage substitution ratio (p<0.05). In addition, the corn silage estimates at the substitution ratio of 30% were similar to those estimated by direct and regression methods. Conclusion: In determining the energy value of corn silage using substitution method, there was a discrepancy between different substitution ratios, and the substitution ratio of 30% was more appropriate than 10% or 60% in the current study. The regression method based on multiple point substitution was more appropriate than single point substitution on energy evaluation of feedstuffs for beef cattle.