• Title/Summary/Keyword: Vascular resistance

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Successful Surgical Correction of Tricuspid Atresia with Complete Transposition of Great Arteries [S.D.D.]. (Modified Fontan 씨 수술법을 이용한 삼첨판막 폐쇄증과 완전대혈관전위증)

  • Park, Geon-Ju;Jo, Jung-Gu;Kim, Gong-Su
    • Journal of Chest Surgery
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    • v.18 no.4
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    • pp.569-573
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    • 1985
  • A 18-year-old female underwent surgical correction of tricuspid atresia and complete transposition of great arteries combined with atrial 8 ventricular septal defect and pulmonary stenosis. After the transection of main pulmonary artery just above the pulmonic valve, proximal portion of main pulmonary artery was closed with running suture and distal portion of main pulmonary artery anastomosed with right atrial appendage without valve insertion. Atrial septal defect was closed with running suture. Postoperative course was uneventful and she discharged on 18th postoperative day. Her condition is in very good until present. Modified Fontan`s operation without valve placement [in the condition of low pulmonary vascular resistance and good left ventricular function] may has a good result.

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Changes in Total Work, Blood Viscosity and Hematocrit during Maximum Strength Type and Endurance Type Resistance Exercise (최대근력 저항운동과 근지구력 저항운동시 총운동량, 혈액점도 및 적혈구용적률의 변화)

  • Jeong, Hwan-Jong;Jang, Tae-Su;Kim, Ki-Hong
    • Journal of the Korean Applied Science and Technology
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    • v.38 no.1
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    • pp.271-279
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    • 2021
  • The purpose of this study was to investigate the effects of maximum and endurance resistance exercises on total work, blood viscosity, and erythrocyte volume ratio. The study subjects were selected as 15 men in their twenties with 12 months or more of resistance exercise experience, and the bench press 1RM was measured before the experiment, and the experiment for each condition was cross-allocated at intervals of one week, and the maximum repetition was performed in 6 sets. As a result, the total amount of exercise showed that the muscular endurance strength was higher than that of the maximum muscular strength (p<.001), and the blood viscosity and erythrocyte volume ratio were higher after exercise than before (p<.01) regardless of the total exercise amount. In summary, it was found that blood viscosity was not affected by exercise intensity and amount of exercise, and increased with one-time resistance exercise. This is clinically significant in constructing a resistance exercise program, and it is considered to be a reference material in creating an exercise program for clinical patients related to vascular disease.

Fontan Operation in a Case of Single Functional Pulmonary Artery (심한 좌폐동맥 형성부전을 동반한 단심실 환아의 폰탄 수술 증례)

  • Kim Joon Bum;Park Jeong-Jun;Park In Sook;Seo Dong Man
    • Journal of Chest Surgery
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    • v.38 no.4 s.249
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    • pp.308-311
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    • 2005
  • The status of pulmonary circulation is regarded with utmost importance for the successful Fontan operation. The absence of unilateral pulmonary artery leads to decreased pulmonary vascular bed and elevated pulmonary vascular resistance which are the risk factors for Fontan operation. A 9-year-8-month-old female patient diagnosed as tricuspid atresia, pulmonary atresia with absent left pulmonary artery flow, received extracardiac conduit Fontan operation using 18 mm Gore-Tex graft. She was discharged on twenty sixth postoperative day with arterial $O_2$ saturation of $70\%$ on room air. On last follow up at 14 months after the operation, she was clinically well with $O_2$ saturation of $91\%$.

Analytical, Numerical, and Experimental Comparison of the Performance of Semicircular Cooling Plates (반원형 구조의 냉각판 성능에 관한 해석적/수치해석적/실험적 비교)

  • Cho, Kee-Hyeon;Kim, Moo-Hwan
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.35 no.12
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    • pp.1325-1333
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    • 2011
  • An analytical, numerical, and experimental comparison of the hydraulic and thermal performance of new vascular channels with semicircular cross sections was conducted. The following conditions were employed in the study: Reynolds number, 30-2000; cooling channels with a volume fraction of the cooling channels, 0.04; and pressure drop, $30-10^5$ Pa. Three flow configurations were considered: first, second, and third constructal structures with diameters optimized for hydraulic operations. To validate the proposed vascular designs by an analytical approach, 3-D numerical analysis was performed. The numerical model was also validated by the experimental data, and the comparison results were in excellent agreement in all cases. The validation study against the experimental data showed that compared to traditional channels, the optimized structure of the cooling plates could significantly enhance heat transfer and decrease pumping power.

Effects of Na-K Pump Inhibition on Contractility of Resistant Arteries in the Rabbit (저항동맥의 수축성에 대한 연구)

  • Ham, Si-Yeong;Kim, Gi-Hwan;Seo, Gyeong-Pil
    • Journal of Chest Surgery
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    • v.28 no.12
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    • pp.1079-1095
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    • 1995
  • Recently endogenous digitalis-like substances were found in the blood of various cardiovascular diseases and they have been considered one of the causes of evoking hypertension. However, the mechanism of endogenous digitalis-like substances-induced hypertension is not clarified yet. Therefore, the effects of Na-K pump inhibition on the contractility of vascular smooth muscle[conduit and resistant artery were investigated, using organ bath and bioassay experiment. Aortic and carotid arterial rings[conduit artery and the branches of brachial and superior mesenteric artery[resistant artery were used to find the effect of Na-K pump inhibition. The results obtained were as followes;The magnitudes of contractions induced by norepinephrine, serotonin, or acetylcholine in all these arteries were significantly increased by the inhibition of Na-K pump. The increased contractile responses to these agonists, especially to serotonin, were much more prominant in resistant arteries. Nitroprusside-induced relaxations were attenuated by Na-K pump inhibition and there were no significant differences in the effects of Na-K pump inhibition on nitroprusside-induced relaxations of these blood vessels. Endothelium-dependent relaxation was suppressed by the inhibition of Na-K pump, especially by the administration of ouabain, and this inhibitory effect was much more prominent in the branches of superior mesenteric artery, compared with other arteries. In the branches of superior mesenteric arteries, endothelium-dependent relaxation was completely blocked by ouabain. The release of EDRF was partially suppressed by Na-K pump inhibition.From the above results, it is suggested that the hypertension due to the increase in vascular resistance can be evoked by the inhibition of Na-K pump and endogenous digitalis-like substances induce hypertension through this mechanism.

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Role of Nitric Oxide Produced During Endotoxic Shock in Sympathetic Nervous Function (Endotoxin에 의해 생성된 혈관의 nitric oxide가 교감신경계에 미치는 영향)

  • 박관하
    • Toxicological Research
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    • v.12 no.2
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    • pp.195-201
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    • 1996
  • Endotoxic shock causes death in humans and animals via extreme hypoperfusion of peripheral organs. A massive production of nitric oxide (NO) both from the endothelical cells and smooth muscle cells has been proposed as a possible mechanism in this process. Since NO attenuated the contractility to vasoconstricting agents such as norepinephrine (NE) by directly acting on the smooth muscle cells, this mechanism was considered mainly as a postsynaptic mechanism. In this research it was investigated whether NO, thus released, also participates in the presynaptic events for the regulation of vascular tone in endotoxic shock. The role of NO was studied by adding NO donors or NO synthase inhibitor $N^\omega $methyl-L-arginine (NMA) in stimulated sympathetic nerves of the mesenteric vascular bed and the Langendorff heart of rats. Sodium nitroprusside (SNP), an NO donor, reduced the pressor responses of isolated mesenteric artery either to electrical stimulation or exogenously administered phenylephrine (PE). In this mesentery, although neither agent influenced NE release, in the presence of the adrenergic $\alpha_2$-receptor antagonist yohimbine, elecrical stimulation-evoked NE release was augumented by SNP. In the heart SNP facilitated the NE release induced by electrical stimulation, while NMA had no effect. From these results it is proposed that there exists a local reflex phenomenon in the junction between the sympathetic nerve terminals and the smooth muscle of resistance blood vessels; by which sympathetic responses are reduced by NO at the postjunctional level while NO facilitates NE release contributing to augumentation of sympathetic tone. All these facts suggest that NO produced during endotoxic shock has dual effects: whereas NO blunts the vasoconstrictive activity of NE at the postsynaptic level, NO presynaptically facilitates the release of NE from sympathetic nerve terminals.

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The Effects of Nitric Oxide Inhibitor on Hyperdynamic Circulation in Portal Hypertensive Rats (산화 질소 억제제가 문맥 고혈압 쥐의 혈역학 변화에 미치는 영향)

  • Kim, Pill-Young;Jang, Byeong-Ik;Kim, Tae-Nyeun;Chung, Moon-Kwan
    • Journal of Yeungnam Medical Science
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    • v.16 no.2
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    • pp.181-192
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    • 1999
  • Background: Nitric oxide, a vasodilator synthesized from L-arginine by vascular endothelial cells, accounts for the biological activity of endothelium derived relaxing factor. Previous studies demonstrated that nitric oxide inhibitor, $N^{\omega}$-Nitro-L-Arginine(NNA) diminished the hyperdynamic splanchnic and systemic circulation in portal hypertensive rats The present study was done to determine the role of nitric oxide in the development of hyperdynamic circulations in the prehepatic portal hypertensive rat model produced by partial portal vein ligation. Methods: The portal hypertensive rats were divided into water ingestion group and NNA ingestion group. After partial portal vein ligation, NNA ingestion group and water ingestion group received NNA 1mg/kg/day and plain water through the mouth for 14 days, respectively. Cardiac output, mean arterial pressure, organ blood flow and porto-systemic shunting were measured by radioisotope labeled microsphere methods. Vascular resistances were calculated by standard equation. Results: There were significant decreases in mean arterial pressure, increases in cardiac output and cardiac index, and decreases in total systemic and splanchnic vascular resistance in portal hypertensive rats compared to normal control group (p<0.01). Compared to the water ingestion group, significantly increased mean arterial pressure with decreased cardiac output and cardiac index were developed in the NNA ingestion group. Total systemic and splanchnic vascular resistance were significantly increased in the NNA ingestion group compared to water ingestion group (p<0.05). But, there was no significant difference in portal pressure between the two groups. Conclusion: The hemodynamic results of this study indicate that hyperdynamic circulation in prehepatic portal hypertensive rat mode1 was attenuated by ingestion of NNA. Nitric oxide may play an important role in the development of hyperdynamic circulation with splanchnic vasodilation in chronic portal hypertension.

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Attenuation of pneumoperitoneum-induced hypertension by intra-peritoneal lidocaine before pneumoperitoneum in laparoscopic cholecystectomy (복강경 담낭절제술 시 공기배증 전에 주입한 복강 내 lidocaine의 공기배증 후 혈압상승 완화효과)

  • Song, Sun Ok;Lee, Hae Mi;Yun, Sung Soo;Yu, Hwarim;Shim, Soo Young;Kim, Heung Dae
    • Journal of Yeungnam Medical Science
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    • v.33 no.2
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    • pp.90-97
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    • 2016
  • Background: We have previously found that intra-peritoneal lidocaine instillation before pneumoperitoneum attenuates pneumoperitoneum-induced hypertension. Whether this procedure alters patient's hemodynamic status during operation should be determined for clinical application. This study elucidated the possible mechanism of the attenuation of the pneumoperitoneum-induced hypertension by intra-peritoneal lidocaine before pneumoperitoneum. Methods: Thirty-four patients underwent laparoscopic cholecystectomy (LC) were randomly allocated into two groups. After induction of general anesthesia, 200 mL of 0.2% lidocaine (lidocaine group, n=17), or normal saline (control group, n=17) were sub-diaphragmatically instilled 10 minutes before pneumoperitoneum. The changes in systolic blood pressure, heart rate, central venous pressure, stroke volume, cardiac output, and systemic vascular resistance were compared between the groups. The number of analgesics used during post-operative 24 h was compared. Results: Systolic blood pressure was elevated during pneumoperitoneum in both groups (p<0.01), but the degree of elevation was significantly reduced in the lidocaine group than in the control (p<0.01). However, stroke volume and cardiac output were decreased and systemic vascular resistance was increased after induction of pneumoperitoneum (p<0.05) without statistical difference between two groups. The number of analgesics used was significantly reduced in the lidocaine group (p<0.01). Conclusion: These data suggest that intra-peritoneal lidocaine before pneumoperitoneum does not alter patient's hemodynamics, and attenuation of pneumoperitoneum-induced hypertension may be the consequence of reduced intra-abdominal pain rather than the decrease of cardiac output during pneumoperitoneum. Therefore, intra-peritoneal lidocaine instillation before pneumoperitoneum is a useful method to manage an intraoperative pneumoperitoneum-induced hypertension and to control postoperative pain without severe detrimental hemodynamic effects.

Descending Aorta Blood Flow Characteristics before the Development of Necrotizing Enterocolitis in Preterm Neonates

  • Kim, Kyung Min;Kim, Hyo Sup;Yoon, Ji Hong;Lee, Eun-Jung;Yum, Sook Kyung;Moon, Cheong-Jun;Youn, Young-Ah;Kwun, Yoo Jin;Lee, Jae Young;Sung, In Kyung
    • Neonatal Medicine
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    • v.25 no.2
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    • pp.78-84
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    • 2018
  • Purpose: To investigate the hemodynamic risk factors for necrotizing enterocolitis (NEC), we analyzed the characteristics of descending aorta (DA) blood flow in preterm neonates, who later developed NEC. Methods: This was an observational case-control study on 53 preterm neonates at a tertiary referral center. Clinical and echocardiographic data were collected from 23 preterm neonates with NEC (NEC group), and compared with those of 30 preterm neonates without NEC (control group). Echocardiography was done at a median (interquartile range) of 5 (3-9) days after birth and 2 (1-2.5) days before the diagnosis of NEC. Results: Basic clinical characteristics including gestational age, birth weight, Apgar score, breast feeding status, use of umbilical catheters, and mode of invasive ventilator care were similar between the groups. Compared with the control group, the lowest diastolic velocity of DA was significantly decreased, whereas the diastolic reverse flow and the ratio of diastolic reverse to systolic forward flows were significantly increased in the NEC group. In addition, the resistive index (RI) of DA was significantly increased in the NEC group and showed a positive association with the development of NEC. Multivariate logistic regression analysis showed that increasing RI of DA was an independent risk factor for the development of NEC (P=0.008). Conclusion: Significant changes in DA flow characteristics including decreased diastolic velocity and increased diastolic reverse flow along with increased peripheral vascular resistance were observed before the development of NEC in preterm neonates. These findings may help clinicians stratify in advance neonates at a risk of developing NEC and may help improve outcomes in these neonates.

Alteration of Vascular Reactivity in Cadmium-poisoned Rabbits (카드뮴 중독(中毒)에 의한 이곡혈관운동성(耳穀血管運動性)의 변동(變動))

  • Hong, Ki-Whan;Rhim, Byung-Yong
    • The Korean Journal of Pharmacology
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    • v.18 no.1
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    • pp.23-31
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    • 1982
  • 1) Experiments were undertaken to elucidate the mechanism which elevates the systemic arterial blood pressure by cadmium (Cd). 2) The mean arterial pressure and peripheral resistance of central ear artery in Cd-poisoned rabbit were significantly increased in comparison with those in control. 3) The vascular pressure response to electrical stimulation in Cd-poisoned group was less than that in control. However, in the former group it showed the supersensitivity to norepinephrine. 4) The response to electrical stimulation was diminished by sodium arachidonate in the ear artery, on the contrary, it was rather enhanced in the vessel of Cd-poisoned group. The responses in both groups were reduced by pretreatment with either $PGE_2\;or\;PGF_{2{\alpha}}$. 5) The response to electrical stimulation was not affected in control, but enhanced in Cd-poisoned group by pretreatment with indomethacin. 6) When the ear artery of control group was perfused with physiological salt solution (PSS) the response to electrical stimulation was not changed by indomethacin, it was much enhanced without affecting on the response to norepinephrine when $K^+-free\;PSS$, was used. These results demonstrate the evidence that the alteration of regulatory mechanism on the vessels was causally related to the elevation of arterial pressure and the increase in peripheral resistance in Cd-poisoned rabbits.

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