• Title/Summary/Keyword: Venous pressure

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A Three-dimensional Biomechanical Model for Numerical Simulation of Dynamic Pressure Functional Performances of Graduated Compression Stocking (GCS)

  • Liu, Rong;Kwok, Yi-Lin;Li, Yi;Lao, Terence-T;Zhang, Xin;Dai, Xiao-Qun
    • Fibers and Polymers
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    • v.7 no.4
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    • pp.389-397
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    • 2006
  • The beneficial effects of graduated compression stockings (GCS) in prophylaxis and treatment of venous disorders of human lower extremity have been recognized. However, their pressure functional performances are variable and unstable in practical applications, and the exact mechanisms of action remain controversial. Direct surface pressure measurements and indirect material properties testing are not enough for fully understanding the interaction between stocking and leg. A three dimensional (3D) biomechanical mathematical model for numerically simulating the interaction between leg and GCS in dynamic wear was developed based on the actual geometry of the female leg obtained from 3D reconstruction of MR images and the real size and mechanical properties of the compression stocking prototype. The biomechanical solid leg model consists of bones and soft tissues, and an orthotropic shell model is built for the stocking hose. The dynamic putting-on process is simulated by defining the contact of finite relative sliding between the two objects. The surface pressure magnitude and distribution along the different height levels of the leg and stress profiles of stockings were simulated. As well, their dynamic alterations with time processing were quantitatively analyzed. Through validation, the simulated results showed a reasonable agreement with the experimental measurements, and the simulated pressure gradient distribution from the ankle to the thigh (100:67:30) accorded with the advised criterion by the European committee for standardization. The developed model can be used to predict and visualize the dynamic pressure and stress performances exerted by compression stocking in wear, and to optimize the material mechanical properties in stocking design, thus, helping us understand mechanisms of compression action and improving medical functions of GCS.

Role of the Inferior Thyroid Vein after Left Brachiocephalic Vein Division During Aortic Surgery

  • Park, Hyung-Ho;Kim, Bo-Young;Oh, Bong-Suk;Yang, Ki-Wan;Seo, Hong-Joo;Lim, Young-Hyuk;Kim, Jeong-Jung
    • Journal of Chest Surgery
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    • v.35 no.7
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    • pp.530-534
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    • 2002
  • Background: In aortic surgery, division and ligation of the left brachiocephalic vein(LBV) may improve exposure of the aortic arch but controversy continues about the safety of this division and whether a divided vein should be reanastomosed after arch replacement was completed. The safety of LBV division and the fate of the left subclavian venous drainage after LBV division were studied. Material and Method: From November 1998 to January 2001, planned division and ligation of the LBV on the mid-line after median sternotomy was peformed in 10 patients during the aortic surgery with the consideration of local anatomy and distal aortic anastomosis. Assessment for upper extremity edema and neurologic symptoms, measurement of venous pressure in the right atrium and left internal jugular vein, and digital subtraction venography(DSV) of the left arm were made postoperatively. Result: In 10 patients there was improvement in access to the aortic arch for procedures on the ascending aorta or aortic arch. The mean age of patients was 62 years(range 24 to 70). Follow-up ranged from 3 weeks to 13 months. One patient died because of mediastinitis from methicilline-resistant staphylococcus aureus strain. All patients had edema on the left upper extremity, but resolved by the postoperative day 4. No patient had any residual edema or difficulty in using the left upper extremity during the entire follow-up period. No patient had postoperative stroke. Pressure difference between the right atrium and left internal jugular vein was peaked on the immediate postoperative period(mean peak pressure difference = 25mmHg), but gradually decreased, then plated by the postoperative day 4. In all DSV studies left subclavian vein flowed across the midline through the inferior thyroid venous plexus. Conclusion: We conclude that division of LBV is safe and reanastomosis is not necessary if inferior thyroid vein, which is developed as a main bridge connecting the left subclavian vein with right venous system, is preserved.

Relationship Among Dietary Intake, Blood Level, and Urinary Excretion of Minerals and Blood Pressure in Korean Rural Adult Men and Women (농촌 성인 남녀의 무기질 섭취량, 혈액수준 및 소변중 배설량과 혈압과의 관계에 대한 연구)

  • 승정자
    • Journal of Nutrition and Health
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    • v.26 no.1
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    • pp.89-97
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    • 1993
  • This study was carried out to estimate the relationship between dietary intake, blood level, and urinary excretion of minerals and blood pressure in 30 healthy adults living in rural area of Korea(12 males and 18 females). Analysis for the nutritional status of the subjects were performed by 3-day dietary intake record, duplicated diet collection, 24-hour urine collection, and venous blood sampling before measuring blood pressure. The mean blood pressure of subjects was 117.50/80.83mmHg in males and 110.00/73.89mmHg in females. The mean daily intakes of Na, K, Ca, P, Mg, Fe, Cu, Zn estimated for 3 days were 199.97mEq, 49.56mEq, 452.50mg, 725.57mg, 240.40mg, 12.48mg, 3.41mg, 8.28mg, respectively. The serum concentration of Na, K, Ca, P, Mg, Fe, Cu, Zn were 139.83mEq/dl, 4.06mEq/dl, 8.86mg/dl, 3.28mg/dl, 2.13mg/dl, 0.12mg/dl, 0.12mg/dl, 0.14mg/dl, respectively. The 24-hour urinary excretions of Na, K, Ca, p, Mg, Fe, Cu, Zn estimated for 169.60mEq, 39.37mEq, 80.40mg, 398.97mg, 64.77mg, 0.21mg, 0.07mg, 0.29mg, respectively. No significant correlation was found between dietary intake, serum concentration, and urinary excretion of minerals and blood pressure. But, the serum Ca/Mg ratio showed negative correlation with the systolic and diastolic blood pressure at the level of significance of 5%. The study verifies the need for more systematic studies on interrelationship among minerals and mineral requirements in normotensive and hypertensive subjects.

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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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Experimental Studies on Extracorporeal Circulation by Rygg-Kyvsgaard Heart-Lung Machine, Hartman`s Solution Prime,and Moderate Hypothermia: [Part I] (Hartmann`s 용액으로 충진한 혈희석 체외순환에 관한 실험적 연구: (1보: 심폐기 Rygg-Kyvsgaard 의 혈산화와 혈압 및 혈액상에 미치는 영향))

  • 지행옥
    • Journal of Chest Surgery
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    • v.4 no.2
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    • pp.69-80
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    • 1971
  • Total body perfusion using Rygg-Kyvsgaard Heart-Lung-Machine, Mark IV, Polystan was attempted in the dogs by the hemodilution method with total prime of buffered Hartman's solution and under hypothermia. The first of all, the functions of Rygg--Kyvsgaard Heart-Lung-Machine and the effects of the hemodilution perfusion by buffered Hartman's solution was studied. At the same time the changes of blood pressure, oxygen consumption, and influence on the blood pictures were observed before, during, and in 1-3 days after perfusion. Hemodilution rates were the average 74. 22cc/Kg(the ranges of 67 to 81 cc/Kg) and perfusion flow rates were maintained in the mean 62. 6cc/Kg/min., Although it was possible to check up to 87 cc/ Kg/min. The total body perfusion continued for 60-80 minutes. Hypothermia was employed between $36^{\circ}C$ and $32^{\circ}C$ of the rectal temperature. Arterial pressure was ranged approximately between 68mmHg and 149mmHg, but generally, it was maintained over 80mmHg. Venous pressure was measured between 6.5cm $H_2O$and 11.5cm $H_2O$. Optimum oxygenation can be expected when oxygen flow into the disposable bubble oxygenator was maintained approximately at 3.5 L/min .. Inthis way, the oxygen contents were measured in the mean value of 13.11${\pm}$O.56 vol. % of arterial blood and 8.67+1.08 vol.% of venous blood(P${\pm}$0.86 vol.% in arteriovenous oxygen difference and 2. 97${\pm}$0.62cc/Kg in oxygen consumption were calculated. According to these dates, it is as plain as pikestaff that excellent oxygenation and good tissue perfusion was accomplished. Erythrocyte, hemoglobin and hematocrit were decreased about 38% during extracorporeal circulation and these were not recovered until 1-3 days after perfusion. These decrease was resulted from relatively high degree of hemodilution rate and no blood transfusion to compensate during these experimental studies. The platelets were also decreased about 76% during perfusion, but on the contrary, it was increased progressively after perfusion and in 1-3 days after perfusion was returned to the control level. Leucocyte were also decreased during perfusion, but it was increased progessively after perfusion and in 1-3 days after perfusion exceed the control level. This increase was resulted from postoperative infection of the wound, but its analysis were not changed significantly.

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Effects of Stellate Ganglion Block on the Peri-operative Vasomotor Cytokine Content and Intrapulmonary Shunt in Patients with Esophagus Cancer

  • Guo, Wei;Jin, Xiao-Ju;Yu, Jun;Liu, Yang;Zhang, Jian-Ping;Yang, Da-Wei;Zhang, Lei;Guo, Jiang-Rong
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.21
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    • pp.9505-9509
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    • 2014
  • Objective: To investigate the effects of stellate ganglion block (SGB) on the peri-operative vasomotor cytokine content and intrapulmonary shunt in patients with esophagus cancer who underwent thoracotomy. Materials and Methods: Forty patients undergoing elective resection of esophageal cancer patients who had I~II American Society of Anesthesiologist (ASA) were randomly divided into total intravenous anesthesia group (group N, n=20) and total intravenous anesthesia combined with SGB group (group S, n=20, 0.12 mL/kg 1% lidocaine was used for SGB 10 min before induction). Heart rate (HR), mean arterial pressure (MAP), central venous pressure (CVP), mean pulmonary arterial pressure (MPAP) and continuous cardiac output (CCO) were continuously monitored. The blood from internal jugular vein was drawn respectively before induction ($T_0$), and 30 min ($T_1$), 60 min ($T_2$) and 120 min ($T_3$) after one-lung ventilation (OLV), and 30 min (T4) after two-lung ventilation. The contents of plasma endothelin (ET), nitric oxide (NO) and calcitonin gene-related peptide (CGRP) were detected with enzyme linked immunosorbent assay (ELISA). Meanwhile, arterial and mixed venous blood samples were collected for determination of blood gas and calculation of intrapulmonary shunt fraction (Qs/Qt). Results: During OLV, ET contents were increased significantly in two groups (P<0.05), and no significant difference was presented (P>0.05). NO content in group S was obviously higher than in group N at T3 (P<0.05), whereas CGRP content in group N was markedly lower than in group S at each time point (P<0.05). Qs/Qt was significantly increased in both groups after OLV, but there was no statistical significant regarding the Qs/Qt at each time point between two groups. Conclusions: Total intravenous anesthesia combined with SGB is conducive to regulation of perioperative vasomotor cytokines in thoracotomy, and has little effect on intrapulmonary shunt at the time of OLV.

Effects of Injectable Anesthetics on Fluorescein Retinal Angiographic Phases in Dogs

  • Jang, Jae-Young;Kim, Young-Sam;Kim, Won-Tae;Jung, Chang-Su;Kim, Hyun-Ah;Kim, Min-Su;Yi, Na-Young;Jeong, Man-Bok;Nam, Tchi-Chou;Seo, Kang-Moon
    • Journal of Veterinary Clinics
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    • v.25 no.6
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    • pp.488-493
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    • 2008
  • This study compared the effect of injectable combinations of anesthetics on each of the fluorescein angiographic phases in order to determine the most useful anesthetic combination for the procedure. Acepromazineketamine (AK), xylazine-ketamine (XK), diazepam-ketamine (DK) and zolazepam-tiletamine (ZT) group were administered randomly to 8 dogs with a two-week interval between different combination doses. The vital signs including the heart rate and arterial pressure were measured before anesthesia and every five minutes during anesthesia. Serial angiographic images were obtained after injecting a sodium fluorescein dye (25 mg/kg) and the onset time of arterial phase (AP), arteriovenous phase (AVP), early venous phase (EVP) and late venous phases (LVP) were recorded. The onset time of the AP, AVP and EVP were significantly slower in the AK and XK groups than in the DK and ZT groups. The total duration of the AP and AVP in the AK group was significantly longer than those in the ZT group. The heart rates were significantly higher in the DK and ZT groups. The arterial pressure was significantly higher in the AK and XK groups (p<0.05). There were significant differences in each angiographic onset time and duration depending on the changes in the heart rates and arterial pressure. The AK and XK groups showed a long angiographic duration allowing an accurate evaluation. Overall, it is believed that AK and XK are more useful for performing fluorescein retinal angiography than DK and ZT.

A Prospective Clinical Study of Crystalloid and Colloid Solutions as Priming Additive Fluids for Cardiopulmonary bypass of the Small Children (소아에서 인공심폐기 충전액의 첨가용액으로서 사용한 crystalloid와 colloid 용액에 관한 임상연구)

  • Han, Jae-Jin;Seo, Gyeong-Pil
    • Journal of Chest Surgery
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    • v.25 no.5
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    • pp.469-479
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    • 1992
  • Searching for the clinical effects of colloid solutions that used to increasing the oncotic pressure of priming solutions at the cardiopulmonary bypass, 29 patients [who were diagnosised as simple VSD around 10kg of body weight and scheduled to be operated from June 1990 to December 1990 at Sejong General Hospital] were divided randomly and prospectively to the two groups: A group [15] was received 4gm% albumin as addition to the priming solutions and B Group [14] the same amount of Ringer`s lactated solution. 34 clinical parameters [Body weight, sex, age, body surface area, Qp/Qs, pulmonary arterial pressure, cardiopulmonary bypass time, anesthetic time, intraoperatively infused crystalloid and colloid amount, hemoglobin, hematocrit, serum sodium concentration, serum osmolarity, urine osmolarity, urine specific gravity, serum concentration, serum osmolarity, urine osmolarity, urine specific gravity, serum protein, serum albumin concentration, urine output, central venous pressure, postoperatively infused colloid amount, immedediate post-operative peak inspiratory pressure, cardiac index, blood pressure and pump flow during cardiopulmonary bypass, inotro-pic assist, diuretics, extubation period, total drain amount, duration of ICU] were measured and compaired between the two groups. There were no differences of preoperative and operative clinical parameters. And postoper-atively, practically there were no nearly differences at the clinical outcomes between the two groups, but some parameters [cardiac index, PIP, BP and pumpflow during CPB, etc] contributed to being preferable to the Group A at certain times [P<0.05]. Conclusively, it might be thought that the priming solution of cardiopulmonary bypass added by colloid solution had some beneficial effects on the patients, especially younger and associated with complex anomaly to be expected taken longer time of cardiopulmonary bypass, and more studies about the neonatal and complex anomaly cases were needed in that points.

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Rebound Pulmonary Hypertension After Nitric Oxide Withdrawal (산화질수(Nitric Oxide) 중단 후의 반동성폐고혈압)

  • 이현우;이재웅;현성열;박철현;박국양;이경천
    • Journal of Chest Surgery
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    • v.33 no.2
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    • pp.132-138
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    • 2000
  • Background: Inhaled nitric oxide therapy causes selective pulmonary vasodilation in congenital heart diseases with pulmonary hypertension. However discontinuation of inhaled nitric oxide therapy may be complicated by abrupt life-threatening rebound pulmonary hypertension(RPH) The purpose of this study was to prevent by comparing group I(without RPH n=13) and group II(with RPH n=6) to determine the risk factors involved inthe development of the RPH. Material and Method: Between Januarty 6, 1998 and April 14, 1999. we studied 19 consecutive children who were treated with inhaled nitric oxide for clinically significant pulmonary hypertension after an open heart surgery for congenital heart disease. the ratio of males and females was 12:7 ranging in age from 10 days to 6040 days(16 years) To identify the effects of nitric oxide between two groups we measured heart rate mean and systolic pulmonary arterial pressure mean and systolic systemic arterial pressure central venous pressure pH paO2/FiO2 and O2 saturation before and after the initiation and just before the withdrawal of the inhaled nitric oxide. result: In 6 of 19 patients(32%) withdrawal of inhaled nitric oxide caused RPH. In the two groups inhaled nitrix oxide decreased in pulmonary arterial pressure(PAP) without decreasing the systemic arterial pressure(SAP) and increased PaO2/FiO2 Compared with patients who had no RPH(group I) patients who had RPH(group II) were older in age (1204$\pm$1688 versus 546$\pm$1654 days p<0.05) received less nitric oxide therapy(34$\pm$18 versus 67$\pm$46 hours p<0.05) has shorter weaning process(5$\pm$3 versus 15一13 hours p<0.05) and received lowerconcentration of initial nitric oxide supply(11$\pm$8 versus 17$\pm$8 ppm p>0.05) and lower concentration just before the withdrawal nitric oxide(4.2$\pm$2.6 versus 5.6$\pm$2.6 ppm, p>0.05) Conclusion : We speculate that older age shorter of nitric oxide therapy shorter weaning process are the risk factors of RPH.

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Simulation of Cardiovascular System for an Optimal Sodium Profiling in Hemodialysis

  • Lim, K.M.;Min, B.G.;Shim, E.B.
    • International Journal of Vascular Biomedical Engineering
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    • v.2 no.2
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    • pp.16-26
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    • 2004
  • The object of this study is to develop a mathematical model of the hemodialysis system including the mechanism of solute kinetics, water exchange and also cardiovascular dynamics. The cardiovascular system model used in this study simulates the short-term transient and steady-state hemodynamic responses such as hypotension and disequilibrium syndrome (which are main complications to hemodialysis patients) during hemodialysis. It consists of a 12 lumped-parameter representation of the cardiovascular circulation connected to set-point models of the arterial baroreflexes, a kinetic model (hemodialysis system model) with 3 compartmental body fluids and 2 compartmental solutes. We formulate mathematically this model in terms of an electric analog model. All resistors and most capacitors are assumed to be linear. The control mechanisms are mediated by the information detected from arterial pressoreceptors, and they work on systemic arterial resistance, heart rate, and systemic venous unstressed volume. The hemodialysis model includes the dynamics of urea, creatinine, sodium and potassium in the intracellular and extracellular pools as well as fluid balance equations for the intracellular, interstitial, and plasma volumes. Model parameters are largely based on literature values. We have presented the results on the simulations performed by changing some model parameters with respect to their basal values. In each case, the percentage changes of each compartmental pressure, heart rate (HR), total systemic resistance (TSR), ventricular compliance, zero pressure filling volume and solute concentration profiles are represented during hemodialysis.

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