• Journal of Chest Surgery
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• v.6 no.1
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• pp.7-14
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• 1973

Ventilatory functions and arterial respiratory gases were studied in 24 patients who underwent resectional surgery for pulmonary tuberculosis. Postoperative measurements were made 24 hours, 72 hours and 7 days after surgery and the results were compared to preoperative values. Twenty-four hours postoperatively, there occurred striking increase in respiratory rate, minute ventilation, dead space ventilation and dead space tidal volume ratio, and the increase in minute ventilation was caused primarily by the increase in respiratory rate. However, alveolar ventilation, oxygen consumption, carbon dioxide elimination and respiratory quotient showed no significant postoperative changes although two of the last values showed slight decreases 24 hours after surgery. The lowest arterial oxygen saturation level was obtained 24 hours postoperatively followed by gradual rises but not to the preoperative levels until 7 days after surgery. A decreased arterial carbon dioxide tension with elevated pit was noted 24 hours after surgery, which returned to the preoperative level on the following measurement.

• The Korean Journal of Emergency Medical Services
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• v.9 no.2
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• pp.55-78
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• 2005

The purpose of this study was to provide basic data for the improvement of the guidelines and training programs regarding the cardiopulmonary resuscitation performance of bystanders who can respond to the incidents in earlier times as the first responder of the cardiac arrest incident, by reviewing the performance of basic CPR and the influencing factors after providing 70 students of Department of Emergency Medical Technology with the CPR training. For the purpose of the study, the collected data were computerized and analyzed by SPSS-WIN program(ver. 10.1). The results for this study were as follows The duration of session between the groups in the BLS CPR were 3 minutes and 36 seconds, 2 minutes and 32 seconds respectively. The average compression number per minute were 24.3 times and 33,2 times respectively(p=.000), and the average compression rate per minute were 112 times and 122 times respectively(p=.000). The average ventilation number per minute were 3.54 times and 5.1 times respectively(p=.000). The errors in compression "Too shallow" were 20.73 times(34.6%) and 23,23 times(38,7%) out of 60 times in 4 cycles with the standard of 38 nun. In CPR performance results according to gender in the first episode, males showed better results in compression depth as 41.5 mm comparing to females average 38.2 mm(p=.015). When ventilation results were compared according to the use of FS, the average ventilation number per minute, total ventilation per minute and the average volume per episode were significantly higher when FS was not used(<.040), There was no significant difference in ventilation accuracy between two groups. According to the results, we need to improve and distribute portable barrier devices, and to be familiar with those devices. We need to enforce ventilations as well as to include compressions so that faster and more accurate CPR can be performed. Additionally, we need to exclude ventilation only cases, minimize the interference time of chest compression due to inaccurate ventilation, simplify or minimize the complicatedness of CPR performance and responding time related to breathing, provide first responders with various training programs such as initial assessment and ventilations only, or initial assessment and chest compression-only CPR and than provide advanced training with AHA BLS education including CPR for more than two people according to CPR skills and target characteristics.

• Fashion & Textile Research Journal
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• v.7 no.1
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• pp.75-80
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• 2005

The purpose of this study was to investigate the effects of silt ventilation system on physiological responses. We measured rectal temperature, local skin temperature, clothing microclimate, blood pressure, heart rate, energy metabolism, body weight loss and subjective sensation during 70 minute, 50 min exercise period and 20 min rest period. The five women subjects randomly wore sportswear without slit ventilation system(NS sportswear) and sportswear with slit ventilation system(S sportswear) under the environmental condition of $25^{\circ}C$, 50%RH. The results of this study are as follows; Rectal temperature, mean skin temperature, clothing microclimate, blood pressure, heart rate, energy metabolism and body weight loss were significantly lower level in 'S sportswear'. In 'S sportswear', subjects replied less hot, less uncomfortable and less wet. Slit ventilation system can be used for bellow effect which is meaningful device of convection during exercise. We could find out that 'S sportswear' has advantage in physiological function.

• The Korean Journal of Emergency Medical Services
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• v.19 no.2
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• pp.7-17
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• 2015

Purpose: This study aimed to compare the effects of rescue ventilation maneuvers on the quality of two-rescuer cardiopulmonary resuscitation (CPR). Methods: We implemented mouth to mouth (MMV), mouth to pocket mask (MPV) and bag-valve mask ventilation (BMV) maneuvers. Each team of two-nurses was randomized to perform three consecutive sessions of two-rescuer CPR by using three artificial ventilation maneuvers. Results: The subjects were 26 teams of nurses (female: 96.2%, male: 3.8%, age: 26.6 years). Failed ventilation was more frequent in BMV ($2.23{\pm}2.21$, p <.001) than MMV ($0.31{\pm}0.74$) and MPV ($0.38{\pm}0.64$). BMV had more compressions per minute ($93.7{\pm}5.7$) than MMV ($87.0{\pm}7.2$, p = .001) and shorter total compression pause time ($46.1{\pm}5.8sec$) and compression pause fraction ($23.3{\pm}2.2%$) than MMV ($54.8{\pm}10.3sec$, p = .001, $25.5{\pm}3.5%$, p = .001, respectively) and MPV ($53.1{\pm}7.1sec$, p =. 006 and $25.8{\pm}2.6%$, p = .006, respectively). Conclusion: In our simulation study, BMV reduced the compression pause time and increased the number of compressions per minute, thus indicating CPR provided to patients was effective. However, considering the high rate of ventilation failure, we recommend periodic training.

• The Korean Journal of Physiology
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• v.5 no.2
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• pp.29-40
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• 1971

Oxygen consumption, pulmonary ventilation, heart rate, and breathing frequency were measured on 8 men walking on a treadmill carrying load of 9 kg on hand, back, or head. Besides measurements were made on subjects carrying loads of 2.6 kg each on both feet. The speed of level walking was 4, 5, and 5.5km/hr and a fixed speed off km/hr with grades of 0, 3, 6, and 9%. Comparisons were made between free walking without load and walking with various types of loads. The following results were obtained. 1. In level or uphill walking the changes in oxygen consumption, pulmonary ventilation, breathing frequency and heart rate were smallest in back load walking, and largest in hand load walking. The method of back load was most efficient and hand load was the least efficient. The energy cost in head load walking was smaller than that of in hand load walking. It was assumed that foot load costed more energy than hand load. 2. In level walking the measured parameters increased abruptly at the speed of 5.5 km/hr. Oxygen consumption in a free walking at 4 km/hr was 11.4ml/kg b.wt., and 13.1 ml/kg b.wt. 5.5 km/hr, and in a hand load walking at 4 km/hr was 13.9, and 18.8 ml/kg b. wt. at 5.5 km/hr. 3. In uphill walking oxygen consumption and other parameters increased abruptly at the grade of 6%. Oxygen consumption at 4 km/hr and 0% grade was 11.4 ml/kg b. wt., 13.6 at 6% grade, and 16.21/kg b. wt. at 9% grade in a free walking. In back load walking oxygen consumption at 4km/hr and 0% grade was 12.3 ml/kg b.wt.,14.9 at 6% grade, and 18.7 ml/kg b.wt. In hand load walking the oxygen consumption was the greatest, namely, 13.9 at 0% grade, 17.9 at 6%, and 20.0 ml/kg b. wt. at 9% grade. 4. Both in level and uphill walking the changes in pulmonary ventilation and heart rate paralleled with oxygen consumption. 5. The changes in heart rate and breathing frequency in hand load were characteristic. Both in level and uphill walk breathing frequency increased to 30 per minute when a load was held on hand and showed a small increase as the exercise became severe. In the other method of load carrying the Peak value of breathing frequency was less than 30 Per minute. Heart rate showed 106 beats/minute even at a speed of 4 km/hr when a load was held on hand, whereas, heart rate was between, 53 and 100 beats/minute in the other types of load carriage. 6. Number of strides per minute in level walking increased as the speed increased. At the speed floater than 5 km/hr number of strides per minute of load carrying walk was greater than that of free walking. In uphill walk number of strides per minute decreased as the grade increased. Number of strides in hand load walk was greatest and back load walk showed the same number of strides as the free walk.

• Korean Journal of Agricultural Science
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• v.39 no.2
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• pp.271-277
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• 2012

Dimensions, operation conditions and improvement items for round roof windows were investigated in arch shape single-span plastic greenhouse with roof vents, and natural ventilation performance was analyzed based on the ventilation theory. Diameter of round roof windows was mostly 60 cm, and chimney height projected on roof was average 30 cm. Installation space was mostly 5 to 6 m but farmhouse of 10 m and over was 16.7% also. A round roof window which has 60 cm diameter was installed to 6 m space generally and 80 cm diameter was installed to 10 m space, but correct standards did not exist. There were a lot of opinions that ventilation effect of round roof windows is fairly good and user satisfaction is generally excellent. It is problem that there is few effects in summer and that vinyl around each vent tears well and rainwater leaks, and improvement hope item required development of automatic control system. In the wind speed of 0.3 m/s, it was estimated that natural ventilation rates were 0.69, 0.55, 0.50 and 0.48 volumes per minute in case of 2, 4, 6 and 8 m installation space for round roof windows, respectively. It was analyzed that the ratio of ventilation due to buoyancy out of total ventilation were 65.2, 41.9, 29.9 and 22.8% in case of 2, 4, 6 and 8m installation space, respectively. By the round roof windows installed at space of 6 m, ventilation rate was estimated to 0.5 volumes per minute, and we can expect the increase in ventilation rate of 30%. In order to meet the recommended ventilation rate for summer season, we have to install the round roof windows at space of 1 to 2 m. However, it is difficult to apply those installation space because of falling productivity due to lower light transmittance as well as rising costs. It is estimated that the installation space of 6m is appropriate for spring or fall season. Therefore it is necessary to encourage installing the roof windows in single-span plastic greenhouses.

• Clinical and Experimental Emergency Medicine
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• v.3 no.3
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• pp.148-157
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• 2016

Objective Our aim was to compare the compression quality, exercise intensity, and energy expenditure in 5-minute single-rescuer cardiopulmonary resuscitation (CPR) using 15:1 or 30:2 compression-to-ventilation (C:V) ratios or chest compression only (CCO). Methods This was a randomized, crossover manikin study. Medical students were randomized to perform either type of CPR and do the others with intervals of at least 1 day. We measured compression quality, ratings of perceived exertion (RPE) score, heart rate, maximal oxygen uptake, and energy expenditure during CPR. Results Forty-seven students were recruited. Mean compression rates did not differ between the 3 groups. However, the mean percentage of adequate compressions in the CCO group was significantly lower than that of the 15:1 or 30:2 group ($31.2{\pm}30.3%$ vs. $55.1{\pm}37.5%$ vs. $54.0{\pm}36.9%$, respectively; P<0.001) and the difference occurred within the first minute. The RPE score in each minute and heart rate change in the CCO group was significantly higher than those of the C:V ratio groups. There was no significant difference in maximal oxygen uptake between the 3 groups. Energy expenditure in the CCO group was relatively lower than that of the 2 C:V ratio groups. Conclusion CPR using a 15:1 C:V ratio may provide a compression quality and exercise intensity comparable to those obtained using a 30:2 C:V ratio. An earlier decrease in compression quality and increase in RPE and heart rate could be produced by CCO CPR compared with 15:1 or 30:2 C:V ratios with relatively lower oxygen uptake and energy expenditure.

• Clinical and Experimental Pediatrics
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• v.48 no.12
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• pp.1310-1316
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• 2005

Mechanical ventilation in children has some differences compared to in neonates or in adults. The indication of mechanical ventilation can be classified into two groups, hypercapnic respiratory failure and hypoxemic respiratory failure. The strategies of mechanical ventilation should be different in these two groups. In hypercapnic respiratory failure, volume target ventilation with constant flow is favorable and pressure target ventilation with constant pressure is preferred in hypoxemic respiratory failure. For oxygenation, fraction of inspired oxygen($FiO_2$) and mean airway pressure(MAP) can be adjusted. MAP is more important than FiO2. Positive end expiratory pressure(PEEP) is the most potent determinant of MAP. The optimal relationship of $FiO_2$ and PEEP is PEEP≒$FiO_2{\times}20$. For ventilation, minute volume of ventilation(MV) product of tidal volume(TV) and ventilation frequency is the most important factor. TV has an maximum value up to 15 mL/kg to avoid the volutrauma, so ventilation frequency is more important. The time constant(TC) in children is usually 0.15-0.2. Adequate inspiratory time is 3TC, and expiratory time should be more than 5TC. In some severe respiratory failure, to get 8TC for one cycle is impossible because of higher frequency. In such case, permissive hypercapnia can be considered. The strategy of mechanical ventilation should be adjusted gradually even in the same patient according to the status of the patient. Mechanical ventilators and ventilation modes are progressing with advances in engineering. But the most important thing in mechanical ventilation is profound understanding about the basic pulmonary mechanics and classic ventilation modes.

• Journal of Korea Entertainment Industry Association
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• v.14 no.7
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• pp.477-485
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• 2020

This study is a random allocation similar experimental study to compare and analyze the difference in BVM (Bag-Valve-Mask) ventilation volume according to the characteristics of the rescuer's hand and the type of mask using a standardized mannequin. To this end, the Basic Life Resuscitation Education Center of D University in gwangju. Recruiting 39 students who have completed the basic resuscitation course for emergency medical personnel and the Korean-style specialized cardiac rescue course, In addition to measuring the physical characteristics of the hand, the average amount of ventilation per minute using a bag-mask was measured and analyzed. As a result, the type of mask that was not most affected by the characteristics of the hand and provided adequate Minute Ventilation was the soft type (tube, silicone) mask. On the other hard (tube, silicone) masks were found to be unsuitable for general use as they were greatly affected by the characteristics of workers' hands. COVID-19 is currently increasing the risk of transmission to paramedics and patients. Considering this situation, the universal use of a semi-permanent hard-type mask, which is disadvantageous not only for preventing infection but also for proper ventilation, should be avoided. In addition to the ease of use, it should be actively utilized in the field by supplying a soft type mask that can provide stable ventilation even with 'predominance recognition' and proper ventilation.

• The Korean Journal of Emergency Medical Services
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• v.22 no.1
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• pp.49-59
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• 2018

Purpose: The purpose of this study was to develop an assistant device for the promotion of bag-valve-mask ventilation based on a non-equivalent control group pre-test and post-test design. Methods: The experimental tool was a mask assistance device developed by the researchers. Data were analyzed using SPSS 21.0 with the cardiopulmonary resuscitation (CPR) evaluation program from August 18 to 30, 2016. The research tools included general, hand-related, and ventilation-related characteristics. Results: Before and after using the mask assistance device, the tidal volume increased by 64 mL (p<.001) from 461.76 mL to 525.86 mL. The tidal volume for control was 477.86 mL, and there was a statistical difference (p<.05). The ventilation frequency in device users was 10 times per minute for a total of 20 ventilations with before 10.65 after 10 times, and that of the control group was before 10.36 times after 10 times; there was no difference in both groups(p>.05). The accuracy of the assistance device was $81.72{\pm}30.86%$, which was a very high value. However, the accuracy of ventilation in the control group with no assistance device was $18.97{\pm}32.44%$, which was a very low accuracy rate. Conclusion: This study's results suggested utilizing the newly-developed mask assistance device in CPR, and showed increases in tidal volume and accuracy of ventilation using the bag-valve-mask ventilation equipment. The general and hand-related characteristics did not have any effect, so the use of the device proved to increase the efficacy in all users.