• 한국가시화정보학회:학술대회논문집
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• 2006.12a
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• pp.121-124
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• 2006

The arteries are very important in cardiovascular system and easily adapt to varying flow and pressure conditions by enlarging or shrinking to meet the given hemodynamic demands. The blood flow in arteries is dominated by unsteady flow phenomena due to heart beating. In certain circumstances, however, unusual hemodynamic conditions cause an abnormal biological response and often induce circulatory diseases such as atherosclerosis, thrombosis and inflammation. Therefore quantitative analysis of the unsteady pulsatile flow characteristics in the arterial blood vessels plays important roles in diagnosing these circulatory diseases. In order to verify the hemodynamic characteristics, in-vivo measurements of blood flow inside the extraembryonic arterial bifurcation cascade of chicken embryo were carried out using a micro-PIV technique. To analyze the unsteady pulsatile flow temporally, the (low images of RBCs were obtained using a high-speed CMOS camera at 250fps with a spatial resolution of $30{\mu}m\times30{\mu}m$ in the whole blood vessels. In this study, the unusual flow conditions such as flow separation or secondary flow were not observed in the arterial bifurcations. However, the vorticity has large values in the inner side of curvature of vessels. In addition, the mean velocity in the arterial blood vessel was decreased and pulsating frequency obtained by FFT analysis of velocity data extracted in front of the each bifurcation was also decreased as the bifurcation cascaded.

• Annals of Hepato-Biliary-Pancreatic Surgery
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• v.28 no.2
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• pp.115-124
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• 2024

To compare the outcomes of low central venous pressure (CVP) to standard CVP during laparoscopic liver resection. The study design was a systematic review following the PRISMA statement standards. The available literature was searched to identify all studies comparing low CVP with standard CVP in patients undergoing laparoscopic liver resection. The outcomes included intraoperative blood loss (primary outcome), need for blood transfusion, mean arterial pressure, operative time, Pringle time, and total complications. Random-effects modelling was applied for analyses. Type I and type II errors were assessed by trial sequential analysis (TSA). A total of 8 studies including 682 patients were included (low CVP group, 342; standard CVP group, 340). Low CVP reduced intraoperative blood loss during laparoscopic liver resection (mean difference [MD], -193.49 mL; 95% confidence interval [CI], -339.86 to -47.12; p = 0.01). However, low CVP did not have any effect on blood transfusion requirement (odds ratio [OR], 0.54; 95% CI, 0.28-1.03; p = 0.06), mean arterial pressure (MD, -1.55 mm Hg; 95% CI, -3.85-0.75; p = 0.19), Pringle time (MD, -0.99 minutes; 95% CI, -5.82-3.84; p = 0.69), operative time (MD, -16.38 minutes; 95% CI, -36.68-3.39; p = 0.11), or total complications (OR, 1.92; 95% CI, 0.97-3.80; p = 0.06). TSA suggested that the meta-analysis for the primary outcome was not subject to type I or II errors. Low CVP may reduce intraoperative blood loss during laparoscopic liver resection (moderate certainty); however, this may not translate into shorter operative time, shorter Pringle time, or less need for blood transfusion. Randomized controlled trials with larger sample sizes will provide more robust evidence.

• Journal of Biomedical Engineering Research
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• v.21 no.4
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• pp.411-417
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• 2000

This paper describes the analysis of the oscillometric method based on the shape of arterial pressure and proposal of a new algorithm for estimating the blood pressure by computer simulation. In the first step, the arterial pressure model which is able to control the shape of arterial pressure was designed and then we simulated the oscillometric model using both the existing exponential model showing the static arterial pressure-volume relation and the designed arterial pressure model. By analyzing the correlation of characteristic ratio based on the shape of arterial pressure, we could find that the characteristic ratio was not the only standard parameter for estimating systolic and diastolic pressure. We were able to estimate the shape of arterial pressure by computing the correlation of arterial pressure shape with oscillation shape. Finally, we proposed an algorithm which is able to estimate systolic and diastolic pressure according to pressure(Pp) table constructed from the relation of maximum amplitude of oscillation and arterial pressure shape. We tested 60 arterial pressure waveforms having various arterial pressure shape and pulse. As a results, the absolute deviation average values of the estimation of systolic, diastolic and mean pressure were 1.62%, 2.40% and 2.20%, respectively. In conclusions, the proposed algorithm showed the possibility of usefullness in estimating the blood pressure.

• Journal of Korean Academy of Nursing
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• v.31 no.6
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• pp.1034-1043
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• 2001

To determine the frequency of past and present obesity among patients with NIDDM and to identify the differences of body fat, blood pressure and C-peptide/glucose ratio according to obese diabetic patients (BMI$\geq$25 kg/$m^2$) and nonobese (BMI<25 kg/$m^2$). Also the final factor is to observe the anthrometric change patterns in the study. Method: The weight at 20 years-old, previous maximal body weight, and acute weight loss were queried. Current height, body weight, BMI, waist & hip circumferences, waist-hip ratio, skinfold thicknesses, blood pressure, fasting blood glucose, and fasting C-peptide were measured in one hundred sixty-seven NIDDM patients. The differences of the parameters ccording to obese and nonobese, and three anthropometric change patterns were analyzed. Result: Results were as follows: 1. 66.5 % of the NIDDM patients had a history of past obesity as assessed by their maximum weight, while only 33.2% of them were currently obese (p's < 0.001). 2. The waist & hip circumferences, skinfold thicknesses, systolic, diastolic & mean arterial blood pressure in obese patients were greater than those of nonobese patients (all p's < 0.001). 3. The waist and the hip circumferences, and skinfold thicknesses (subscapula & triceps) were highest among the obese-obese group. WHR and abdominal skinfold thickness in the obese-obese and obese-nonobese groups were higher than those in the nonobese- nonobese group. Systolic & diastolic and mean arterial blood pressures in the obese-obese group were higher than those of obese-nonobese and nonobese-nonobese groups(all p's < 0.005). 4. The abdominal and subscapular skinfold thicknesses in female diabetic patients were greater than those of male patients (all p's <0.0001). Conclusion: Although most Korean NIDDM patients were previously obese, many of them were not obese during the course of the study. Greater central and upper body adiposicity and higher blood pressure was shown in obese diabetic patients. Also, greater central and upper body adiposicity was demonstrated in female diabetic patients.

• Journal of Veterinary Clinics
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• v.28 no.1
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• pp.40-45
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• 2011

Cardiovascular changes caused by $CO_2$ pneumoperitoneum during laparoscopic ovariohysterectomy (LOVH) were measured in nine healthy mixed breed dogs ($16.7{\pm}4.6kg$). The dogs were premedicated with the combination of atropine, acepromazine, and butorphanol. General anesthesia was induced with propofol and maintained with isoflurane in oxygen. Controlled ventilation maintained partial pressure of end-tidal $CO_2$ between 35-45 mmHg. The $CO_2$ pneumoperitoneum was maintained at a constant pressure of 12 mmHg and the dog was placed in the $15^{\circ}$ Trendelenburg position as LOVH was performed. Dorsal pedal artery was catheterized for measurements of heart rate (HR) and invasive arterial blood pressure (IBP). Prior to the intraperitoneal insufflation, baseline measurements of HR and IBP were made every minute for a total of 10 min. Then, measurements of HR and IBP were made every 5 min following intraperitoneal insufflation and were also made every 5 min following desufflation for a total of 10 min. The $CO_2$ pneumoperitoneum during LOVH resulted in a significant (P < 0.05) increase in systolic arterial blood pressure at the time of the onset of insufflation. In addition, diastolic and mean arterial blood pressure increased significantly (P < 0.05) at the time of the onset of insufflation and 5 min following insufflation. The mean heart rate did not change significantly during LOVH. Although IBP showed sharp initial rise following the $CO_2$ pneumoperitoneum, the changes were within physiological acceptable limits in these healthy, ventilated dogs.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.6
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• pp.885-890
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• 2012

In this study, a new blood pressure measuring system was proposed and implemented. An additional small-cuff was placed on the center of a inner cuff to measure morphological signals and new oscillometric ratio. The proposed BP-measuring system is composed of an external cuff, an inner cuff and a small-cuff. Oscillation signal from small-cuff is interpolated with 7th-order fitting polynomials and SBP, DBP ratio were 22.2% and 87.7%. Experimental data were gathered from 20 volunteers ($25{\pm}4$ years) and arterial blood pressure values were compared with auscultation, sphygmomanometers, small-cuff and inner-cuff. As a result, the difference in systolic BP between auscultation and the small-cuff was 1.93(${\pm}1.28$) mmHg, and the inner-cuff was 4.53(${\pm}4.39$) mmHg, and sphygmomanometer was 6.68(${\pm}3.99$) mmHg, and the corresponding difference in diastolic BP was 2.50(${\pm}2.04$) mmHg, 3.50(${\pm}3.19$) mmHg, 7.35(${\pm}5.62$), respectively.

• Journal of Physiology & Pathology in Korean Medicine
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• v.28 no.6
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• pp.601-606
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• 2014

The purpose of this study is to research the effects of acupuncturing BL40 and ST36 and to determine the mechanism of action of acupuncturing BL40 and ST36 by measuring the changes of regional cerebral blood flow (rCBF) and mean arterial blood pressure (MABP) in normal rats. To determine the mechanism of action of acupuncturing BL40 and ST36, pretreatment with indomethacine and methylene blue was performed. Acupuncturing BL40 and ST36 significantly increased rCBF, and the increased rCBF by acupuncturing BL40 and ST36 was significantly inhibited by pretreatment with indomethacin (1 mg/kg, i.p.), an inhibitor of cyclooxygenase, and methylene blue($10{\mu}g/kg$, i.p.), an inhibitor of guanylate cyclase. Acupuncturing BL40 and ST36 decreased MABP, and decreased MABP by acupuncturing BL40 and ST36 was not changed by pretreatment with indomethacin and methylene blue. This result suggested that acupuncturing BL40 and ST36 might significantly increase rCBF by dilating arterial diameter and mechanism of acupuncturing BL40 and ST36 might be mediated by cyclooxygenase and guanylate cyclase.

• Journal of Veterinary Clinics
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• v.22 no.3
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• pp.214-219
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• 2005

This experiment was conducted in order to identify the effect of the laryngeal mask airway and it's clinical utility on cardiovascular system, intraocular pressure and stress reaction at the time of anesthesia care. The heart rate, systolic arterial pressure, diastolic arterial pressure and intraocular pressure were significantly reduced in the experimental group to be compared with the control group. But, there were no significant differences in mean arterial pressure, central venous pressure and blood cortisol concentration between both groups. In view of the above results, it is thought that the airway management using the laryngeal mask airway will be useful to reduce the stress condition in the induction of anesthesia.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.186-189
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• 2005

In a clinical setting, developing a reliable method for the automated drug infusion system would improve a drug therapy under the unexpected and acute changes of hemodynamics. The conventional proportional-integral-derivative (PID) controller might not be able to achieve maximum performance because of the unexpected change of the intra- and inter-patient variability. The fuzzy PID control and the conventional PID control were tested under the unexpected response of mean arterial blood pressure (MAP) to a vasopressor agent during acute hypotension. Compared with the conventional PID control, the fuzzy PID control performed the robust MAP regulation regardless of the unexpected MAP response (average absolute value of the error between target value and actual MAP: 0.98 vs. 2.93 mmHg in twice response of the expected MAP and 2.59 vs. 9.75 mmHg in three-times response of the expected MAP). The result was due to the adaptive change of the proportional gain in PID parameters.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.1
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• pp.64-70
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• 2003

Jaeumgenby-tang(JGT) have been used in oriental medicine for many centuries as a therapeutic agent of vertigo caused by deficiency of qi(氣) and blood(血). Effect of Aurantii Fructus(AF) take off the phlegm by promoting the circulation of qi, Gastrodae Rhizoma(GR) has effects treating for headache, vertigo by calming the liver and suppressing hyperactivity of the liver-yang(陽). And, I designed to investigate whether injection of JGT adding AFㆍGR extract(JGTAG) affects cytotoxicity in vitro, cerebral hemodynamics [regional cerebral blood flow(rCBF), pial arterial diameter(PAD), mean arterial blood pressure(MABP)] in normal and cerebral ischemia rats by MCA occlusion method. The changes of rCBF and MABP were determinated by laser-doppler flowmetry(LDF), and the change of PAD was determinated by video microscope and width analyzer. The results were as follows in normal rats; JGTAG was not cytotoxicity in brain cells. And JGTAG was significantly increased rCBF, PAD and MABP. This results suggest that JGTAG increased significantly rCBF by dilating PAD. And the results were as follows in cerebral ischemic rats; The changes of rCBF and PAD were increased stably by treatment with JGTAG(10mg/kg, i.v.) during the period of cerebral reperfusion, and pretreatment with propranolol and indomethacin were increased JGT AG induced increase of rCBF and PAD during the period of cerebral reperfusion. We suggest that JGTAG has an anti-ischemic effect through the improvement of cerebral hemodynamics.