• 제목/요약/키워드: oxygen saturation level

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Effects of Hypovolemic Hypotension on Cardiopulmonary Functions and Acid-Base Balance (출혈성 쇼크가 심폐기능 및 산.염기평형에 미치는 영향)

  • Sou, Won-Young;Lee, Sung-Haing
    • Journal of Chest Surgery
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    • v.6 no.2
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    • pp.131-142
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    • 1973
  • Studies of cardiopulmonary function and acid-base balance were performed on 29 dogs during control period, during oligemic hypotension and following return of blood to the animals. Intravenous morphine and local anesthesia were used. Fifteen of the 29 animals survived the complete experiment. The 14 animals that failed to survive the experimental period died between 15 to 90 minutes after the onset of bleeding. The results were as follows. 1. The heart rate increased after the onset of bleeding and failed to return to control level following reinfusion. Stroke volume decreased markedly after bleeding and failed to recover after return of blood from the reservoir. Cardiac output also decreased during oligemic hypotension and was maintained at this level after re-infusion. Total peripheral resistance decreased significantly immediately after bleeding, however it increased soon over the pre-bleeding level. Central venous pressure decreased after the onset of bleeding and remained at lower level for the rest of the experimental period. Arterial blood pressure, clown to 40-45 mmHg by acute hemorrhage, was elevated near to control level. Left ventricular work decreased tremendously during oligemic hypotension and failed to return to control level with the re-infusion of blood. Hematocrit value showed no significant decrease after bleeding and increased after re-infusion. Hemoglobin decreased after the onset of bleeding and recovered to control value after re-infusion. 2. The respiratory rate fell rapidly after bleeding from 124 to 29 and remained at this lower level for the remainder of the experiment. The tidal volume increased after bleeding and was maintained at this level for the remainder of the experiment. The respiratory minute volume showed no significant changes throughout the experimental period. Oxygen consumption fell lightly in all animals during oligemic hypotension and returned to normal levels following re-infusion. Arterial oxygen content and arterial oxygen saturation decreased following bleeding and the values returned to normal levels after the return of blood from the reservoir The arterio-venous oxygen difference increased after the onset of bleeding. It failed to return to normal values following re-infusion. Arterial $Pco_2$ decreased in all animals after the beginning of the bleeding. Partial pressure of $Co_2$ continued to fall until re-infusion, after which the values returned toward normal. Animals became acidotic. The pH fell to lower level following bleeding. Lactic acid and lactate: pyruvate ratio also increased during same period. Arterial pH and lactic acid failed to return to control value and lactate: pyruvate ratio increased more after re-infusion. Sodium bicarbonate decreased after bleeding and returned to control value following re-infusion.

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Comparative Bioreactor Studies in Terms of Oxygen Transfer between Suspended and Immobilized Fungal Systems for Cyclosporin A Fermentation (Cyclosporin A 생산을 위한 액체배양과 고정화배양의 생물반응기에서의 산소전달 비교 연구)

  • 전계택
    • KSBB Journal
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    • v.9 no.2
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    • pp.211-223
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    • 1994
  • In fermentations with a 4-liter stirred tank bioreactor, a better than two-fold enhancement of the gas-liquid mass transfer coefficient$(k_La)$ in the celite-immobilized fungal cultures of Tolypocladium in flatum over the parallel conventional free-cell was observed at identical biomass concentrations, despite the higher specific oxygen uptake rate of the immobilized fungi during exponential growth. As a result oxygen sufficient conditions, i. e., dissolve oxygen(D.O.) concentrations exceeding 75% air saturation, could be maintained throughout exponential growth period of the immobilized culture, in contrast to the suspended fungal culture, whose D.O. levels fell below 50% air saturation. A linear monotonic dependence of $k_La$ upon impeller agitaion rate was found for both immobilized and conventional cultivation modes over a range of 250 to 550rpm, the slope being a function of biomass concentration for the free but not for the immobilized cell system In contrasts oxygen transfer rate was a much weaker function of aeration rate up to about 2.5 vvm for both culture configurations. Above this level, aeration rate had no further effect on the mass transfer. In addition, the immobilized cultures sustained good morphological and physiological states, leading to almost two times higher cyclosporln A (CyA) productivity overt the parallel free cell system. These experiments suggest that the celite-immobilized fungal system in a stirred tank reactor has considerable promise for scaling up cyclosporin A production in terms of high-density cultivation.

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The Effects of Kangaroo Care on Body Weight, Physiologic Responses and Behavioral States in Premature Infants (캉가루식 돌보기가 미숙아의 체중, 생리적 반응 및 행동 상태에 미치는 효과)

  • 구현영
    • Journal of Korean Academy of Nursing
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    • v.30 no.1
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    • pp.171-182
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    • 2000
  • This study was performed to investigate the effect of kangaroo care on body weight, physiological responses and behavioral states in premature infants. The subjects were 32 premature infants, fifteen for the kangaroo care group and seventeen for the control group, who hospitalized in a neonatal intensive care unit at a university-affiliated hospital. The kangaroo care was applied 8 times during the twenty five days with 40 minutes for each session. The kangaroo care provides the skin-to-skin contact during which a premature infant wearing a diaper and a hat is placed on its mother's chest. As for the measures, body weight was measured everyday. The levels of epinephrine, norepinephrine and 17-OHCS were measured twice, before beginning the first intervention and after finishing the last intervention. While each session of the care is undergoing, such physiological responses were measured periodically as heart rate, respiration rate, oxygen saturation, core temperature and skin temperature. The results were as follows : 1. The weight gain was significantly greater in the kangaroo care group than that in the control group during the period of performing the kangaroo care. 2. No significant difference was revealed between the two groups in heart rate, respiration rate, oxygen saturation and core temperature. The kangaroo care group also showed significant increases in the skin temperature. 3. The differences in the levels of epinephrine, norepinephrine and 17-OHCS were not significant between the kangaroo care and the control groups. The level of norepinephrine in the two groups was significantly increased over time. 4. Sleep pattern changed significantly in the kangaroo group from a very restless sleep to a very quiet sleep. These results suggest that kangaroo care is an effective nursing intervention for premature infants in gaining weight, achieving stable physiological responses and facilitating a quiet sleep.

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Safety and Availability of Monitored-Anesthesia Care using Propofol during Implant Surgery of the One-day Admission Patients (당일 입원 환자의 치과 수술 시 Propofol을 이용한 Monitored-Aesthesia Care (MAC)의 안정성 및 유용성에 관한 연구)

  • Kim, Bum-Soo;Kim, Young-Kyun;Yun, Pil-Young;Lee, Yong-In
    • Journal of The Korean Dental Society of Anesthesiology
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    • v.7 no.2
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    • pp.120-125
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    • 2007
  • Background: Propofol has been used extensively for short-acting intravenous sedative agent during monitored anesthesia care (MAC). This study was designed to evaluate the safety and availability of MAC using propofol in implant surgery of the one-day admission patients. Methods: In this study, subjects were divided into two groups according to ASA physical status. The heart rate, blood pressure, peripheral oxygen saturation and ECG of a patient were estimated under MAC by an anesthesiologist and the vital signs were recorded in recovery room periodically afterwards. The subjective satisfaction with regard to outpatient ambulatory surgery under MAC procedure was evaluated the next day. Results: Systolic and diastolic blood pressure were significantly decreased during MAC in ASA I group, but other remarkable changes in vital sign were not observed. There was no significant difference in pain and anxiety level between ASA I and ASA II, III group. Satisfaction rate was high in both groups. Conclusion: Monitored-Anesthesia Care using propofol during implant surgery of the one-day admission patients might be safe and available procedure because heart rate, blood pressure and oxygen saturation are stable before and during surgery, and adequate control of pain and anxiety is supported.

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Real-time Vital Signs Measurement System using Facial Image Data (안면 이미지 데이터를 이용한 실시간 생체징후 측정시스템)

  • Kim, DaeYeol;Kim, JinSoo;Lee, KwangKee
    • Journal of Broadcast Engineering
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    • v.26 no.2
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    • pp.132-142
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    • 2021
  • The purpose of this study is to present an effective methodology that can measure heart rate, heart rate variability, oxygen saturation, respiration rate, mental stress level, and blood pressure using mobile front camera that can be accessed most in real life. Face recognition was performed in real-time using Blaze Face to acquire facial image data, and the forehead was designated as ROI (Region Of Interest) using feature points of the eyes, nose, and mouth, and ears. Representative values for each channel of the ROI were generated and aligned on the time axis to measure vital signs. The vital signs measurement method was based on Fourier transform, and noise was removed and filtered according to the desired vital signs to increase the accuracy of the measurement. To verify the results, vital signs measured using facial image data were compared with pulse oximeter contact sensor, and TI non-contact sensor. As a result of this work, the possibility of extracting a total of six vital signs (heart rate, heart rate variability, oxygen saturation, respiratory rate, stress, and blood pressure) was confirmed through facial images.

Enhancement in the photocurrent of ZnO nanoparticles by thermal annealing

  • Byun, Kwang-Sub;Cho, Kyuong-Ah;Jun, Jin-Hyung;Seong, Ho-Jun;Kim, Sang-Sig
    • Journal of IKEEE
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    • v.13 no.1
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    • pp.57-64
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    • 2009
  • The optoelectrical characteristics of the ZnO nanoparticles (NPs) annealed in vacuum or oxygen condition from $200^{\circ}C$ to $600^{\circ}C$ were examined. Increased on-off ratio (or, the ratio of photocurrent to dark current) was observed when they were annealed at $300^{\circ}C$, $400^{\circ}C$ and $500^{\circ}C$ with the values enhanced about 4 orders compared to the as-prepared ZnO NPs in both annealing conditions, while the maximum efficiency was shown at the annealing temperature of $600^{\circ}C$ for the ZnO NPs annealed in vacuum with the value of 29.8 mA/W and at the temperature of $500^{\circ}C$ for those annealed in oxygen condition with the value of 40.3 mA/W. Photoresponse behavior of the ZnO NPs annealed in oxygen showed the sharp increase right after the ir exposure to the light followed by the slow decay and saturation during steady illumination, differing from the ZnO NPs annealed in vacuum which only exhibited the gradual increase. This difference occurred due to the curing effect of the oxygen vacancies. SEM images indicated no change in their morphologies with annealing, indicating the change in their internal structures by annealing, and most remarkably at $600^{\circ}C$. As for their photoluminescence(PL) spectra, the decrease of the deep-level(DL) emission was observed when they were annealed in oxygen at $400^{\circ}C$, and not at $200^{\circ}C$ and $600^{\circ}C$.

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A study on the tumor induced microvasculature using hyperspectral imaging system (초분광 이미징 시스템을 이용한 암 혈관 분석에 대한 연구)

  • Choe, Se-woon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2015.05a
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    • pp.622-624
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    • 2015
  • Tumor hypoxia caused by the unique characteristics of solid tumor sites such as lowered vascular density, irregular vasculature, longitudinal oxygen gradient, and unbalanced oxygen consumption has decreased therapeutic efficacy in several clinical trials such as radiation, chemotherapy, and surgery. Hence, tumor oxygenation studies at microvascular levels are important to provide better understanding of the complexity of microvasculature oxygen transport and exchange with tissue. However, polarographic microelectodes, was employed to measure $pO_2$ at the microvasculature level, but it is difficult to perform and does not provide significant spatial and temporal information of oxygen delivery. In this research, we introduce the hyperspectral imaging system able to provide a wide range of vascular characteristics by spatial maps on hemoglobin saturation information for better understanding of the relationship between blood oxygen delivery, hypervascularity, aberrant angiogenesis at microvasculature levels during tumor growth.

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Effect of Dissolved Oxygen on the Production of Epothilone in Bioreactor Cultures Sorangium cellulosum (Sorangium cellulosum의 생물반응기 배양에서 용존산소가 epothilone의 생산에 미치는 영향)

  • Park, Su-Jeong;Han, Se-Jong;Kim, Byung-Woo;Sim, Sang-Jun
    • KSBB Journal
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    • v.24 no.1
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    • pp.65-69
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    • 2009
  • The biological production of a potent anticancer agent, epothilone, by Sorangium cellulosum was carried out using flask and fermentor cultures. Soluble starch was selected as the main carbon source and the concentrations of lactose and yeast extract were optimized at 4 and 0 g/L, respectively, when using the flask cultures. In the fermentor cultures, the cells were cultivated at a high DO level of more than 80% of air saturation in the growth stage and then the DO level was controlled at about 50, 20 or 1-2% when the carbon source was exhausted. The epothilone production increased with decreasing DO level after the exhaustion of the carbon source, and the maximum concentration of epothilone was 5.4 mg/L. It was found that the DO level had significant regulation effects on the epothilone production.

Analysis of Effects of Multiple Environmental Factors on Early Life-history for Growth and Stress Accumulation Using a Dynamic-state-dependent Model (동적상태의존모델을 이용하여 복합적 환경영향이 어류의 초기 생활사에 미치는 영향 분석)

  • Lee, Who-Seung
    • Journal of Environmental Impact Assessment
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    • v.28 no.1
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    • pp.49-62
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    • 2019
  • Environmental changes can affect life-history traits, such as growth rate and reproduction, and organisms adapt on a given environmental condition to maximize ecological fitness. This study shows the effects of water temperature and dissolved oxygen level on early growth and accumulated damage in fish using a dynamic-state-dependent model. I have hypothesized that the level of foraging activity is related to growth and stress and so the optimal level can maximize reproductive success - ultimately, fitness. The critical temperature and dissolved oxygen (DO) is also defined as inducing the maximum growth rate at the level. So, the model predicts the highest growth rate at oxygen saturation and lower growth rate at lower or higher level of DO in water. Lower DO (i.e., hypoxia) causes slower growth rate through higher amount of accumulated stress whereas higher DO (i.e., hyperoxia) induces faster growth rate, but smaller body size. In addition, I show that there is lower impact when considering simple or independent environmental factors on environmental assessment. My findings suggest that multiple environmental factors as physiological ecology approach should be considered to improve impact assessment in environmental changes and a further study is needed to develop advanced assessment tools considering multiple environmental factors.

Selective catalytic reduction of NO by hydrocarbons over $Cu/Al_2O_3$ catalysts

  • Nam, Chang-Mo;Bernard M. Gibbs
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • v.4 no.4
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    • pp.201-208
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    • 2000
  • The reduction of NO by hydrocarbons was investigated over Cu/Al$_2$O$_3$catalysts using a stainless steel flow reactor under highly oxidising diesel exhaust conditions(up to 15%). Three different Cu loadings(1,5 and 10wt.%) on an $Al_2$O$_3$support were prepared and characterized using spectroscopic techniques. The catalytic activity tests show that different Cu loadings as well as temperature, oxygen, and hydrocarbon concentration levels significantly influence the NO reduction. Increasing Cu loadings up to 5 and 10wt.% decreases the catalytic activities for NO reduction due to the formation of a bulk crystalline CuO phase, as observed from XRD and SEM images. In particular, the visualization of the copper dispersion on the surface using the SEM-BEI technique provides information on the extent of copper saturation, particle size, and the effects on NO reduction. However, the lower Cu loading(1 wt.%) increases the catalytic activity with a temperature window of 720-810K, thereby favoring the formation of well dispersed isolated Cu species, e.g. Cu(sup)2+ ions, which is related to selective NO reduction. The effects of other reaction parameters, such as oxygen, the hydrocarbon level and type, and byproduct emissions are further discussed.

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