• Neonatal Medicine
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• v.25 no.1
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• pp.1-6
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• 2018

Extremely low birth weight infants remain at increased risk of intraventricular hemorrhage from the fragile vascular bed of the germinal matrix; the roles of hypotension (ischemia) and reperfusion (hyperemia) in the development of intraventricular hemorrhage are still debated. Cerebrovascular pressure autoregulation protects the brain by maintaining constant cerebral blood flow despite changes in blood pressure. The ontogeny of cerebrovascular pressure autoregulation has not been well established and uncertainty remains about the optimal arterial blood pressure required to support brain perfusion. Another important aspect of premature cerebral hemodynamics is the critical closing pressure--the arterial blood pressure at which cerebral blood flow ceases. Interestingly, in premature infants, the critical closing pressure approximates the mean arterial blood pressure. Often in this unique population, cerebral blood flow occurs only during systole when the diastolic arterial blood pressure is equal to the critical closing pressure. Moreover, the diastolic closing margin, a metric of cerebral perfusion that normalizes diastolic arterial blood pressure to the critical closing pressure, may be a better measure than arterial blood pressure for defining cerebral perfusion in premature infants. Elevated diastolic closing margin has been associated with intraventricular hemorrhage. This review summarizes the current state of understanding of cerebral hemodynamics in premature infants.

• Journal of Chest Surgery
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• v.17 no.3
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• pp.418-423
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• 1984

Appreciation of the large volume deficits which may occur in surgical or trauma patients due to blood loss has led to vigorous transfusion techniques designed to overt hypovolemic shock and ischemic damage to vital organs which may develop in minutes during the hypovolemic state. In a significant proportion of patients treated with massive rapid blood or fluid transfusion, hypervolemia occurs and life threatening pulmonary edema may develop. Especially, hypervolemia may occur during transfusion for preventing development of the so-called low output syndrome following cardiac surgery. However, the most effective indicator which reveals the adequate level of transfusion is not settled yet. The present study was aimed to compare the effectiveness of the indicators suggested thus far and to determine the most sensitive one. Eight dogs were experimentally studied in terms of left atrial pressure, pulmonary arterial systolic pressure, central venous pressure, mean systemic arterial pressure and heart rate before and after induced hypervolemia with infusion of 600ml heparinized homologous blood. Immediately after induced overtransfusion of the blood, pulmonary arterial systolic pressure increased 75.0%, in omparison with the control before transfusion, left atrial pressure 58.8%, central venous pressure 44.6%, and mean systemic arterial pressure 10.1%, one hour after transfusion, pulmonary arterial systolic pressure 40.0%, left atrial pressure 21.2%, central venous pressure 14.5%, and mean systemic arterial pressure 3.2%, central venous pressure 14.5%, and mean systemic arterial pressure 3.2%, respectively. Heart rate showed no significant change throughout the experiment. These result suggested that the changes of the pulmonary arterial systolic pressure is the most sensitive indicator for detection of hypervolemia during blood transfusion.

• The Korean Journal of Nuclear Medicine
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• v.1 no.2
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• pp.1-25
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• 1967

In 20 normal cases and 39 pulmonary tuberculosis cases, regional pulmonary arterial blood flow measurements and lung perfusion scans by $^{131}I$-Macroaggregated albumin, lung inhalation scans by colloidal $^{198}Au$ and spirometries by respirometer were done at the Radiological Research Institute. The measured lung function tests were compared and the results were as the following: 1. The normal distribution of pulmonary blood flow was found to be $54.5{\pm}2.82%$ to the right lung and $45.5{\pm}2.39%$ to the left lung. The difference between the right and left pulmonary arterial blood flow was significant statistically (p<0.01). In the minimal pulmonary tuberculosis, the average distribution of pulmonary arterial blood flow was found to be $52.5{\pm}5.3%$ to the right lung and $47.5{\pm}1.0%$ to the left lung when the tuberculous lesion was in the right lung, and $56.2{\pm}4.4%$ to the right lung and $43.8{\pm}3.1%$ to the left lung when the tuberculous lesion was in the left lung. The difference of pulmonary arterial blood flow between the right and left lung was statistically not significant compared with the normal distribution. In the moderately advanced pulmonary tuberculosis, the average distripution of pulmonary arterial blood flow was found to be $26.9{\pm}13.9%$ to the right lung and $73.1{\pm}13.9%$ to the left lung when the tuberculous lesion was more severe in the right lung, and $79.6{\pm}12.8%$ to the right lung and $20.4{\pm}13.0%$ to the left lung when the tuberculous lesion was more severe in the left lung. These were found to be highly significant statistically compared with the normal distribution of pulmonary arterial blood flow (p<0.01). When both lungs were evenly involved, the average distribution of pulmonary arterial blood flow was found to be $49.5{\pm}8.01%$ to the right lung and $50.5{\pm}8.01%$ to the left lung. In the far advanced pulmonary tuberculosis, the average distribution of pulmonary arterial blood flow was found to be $18.5{\pm}11.6%$ to the right lung and $81.5{\pm}9.9%$ to the left lung when the tuberculous lesion was more severe in the right lung, and $78.2{\pm}8.9%$ to the right lung and $21.8{\pm}10.5%$ to the left lung when the tuberculous lesion was more severe in the left lung. These were found to be highly significant statistically compared with the normal distribution of pulmonary arterial blood flow (p<0.01). When both lungs were evenly involved the average distribution of pulmonary arterial blood flow was found to be $56.0{\pm}3.6%$ to the right lung and $44.0{\pm}3.2%$ to the left lung. 2. Lung perfusion scan by $^{131}I$-MAA in patients with pulmonary tuberculosis was as follows: a) In the pretreated minimal pulmonary tuberculosis, the decreased area of pulmonary arterial blood flow was corresponding to the chest roentgenogram, but the decrease of pulmonary arterial blood flow was more extensive than had been expected from the chest roentgenogram in the apparently healed minimal pulmonary tuberculosis. b) In the pretreated moderately advanced pulmonary tuberculosis, the decrease of pulmonary arterial blood flow to the diseased area was corresponding to the chest roentgenogram, but the decrease of pulmonary arterial blood flow was more extensive in the treated moderately advanced pulmonary tuberculosis as in the treated minimal pulmonary tuberculosis. c) Pulmonary arterial blood flow in the patients with far advanced pulmonary tuberculosis both before and after chemotherapy were almost similar to the chest roentgenogram. Especially the decrease of pulmonary arterial blood flow to the cavity was usually greater than had been expected from the chest roentgenogram. 3. Lung inhalation scan by colloidal $^{198}Au$ in patients with pulmonary tuberculosis was as follows: a) In the minimal pulmonary tuberculosis, lung inhalation scan showed almost similar decrease of radioactivity corresponding to the chest roentgenogram. b) In the moderately advanced pulmonary tuberculosis the decrease of radioactivity in the diseased area was partly corresponding to the chest roentgenogram in one hand and on the other hand the radioactivity was found to be normally distributed in stead of tuberculous lesion in the chest roentgenogram. c) In the far advanced pulmonary tuberculosis, lung inhalation scan showed almost similar decrease of radioactivity corresponding to the chest roentgenogram as in the minimal pulmonary tuberculosis. 4. From all these results, it was found that the characteristic finding in pulmonary tuberculosis was a decrease in pulmonary arterial blood flow to the diseased area and in general decrease of pulmonary arterial blood flow to the diseased area was more extensive than had been expected from the chest roentgenogram, especially in the treated group. Lung inhalation scan showed almost similar distribution of radioactivity corresponding to the chest roentgenogram in minimal and far advanced pulmonary tuberculosis, but there was a variability in the moderately advanced pulmonary tuberculosis. The measured values obtained from spirometry were parallel to the tuberculous lesion in chest roentgenogram.

• Clinical and Experimental Pediatrics
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• v.45 no.4
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• pp.449-453
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• 2002

Purpose : Arterial blood gas analysis is frequently performed in neonatal intensive care unit (NICU) to evaluate ventilation and the metabolic state of critically ill infants. In occasions when umbilical arterial catheterization is not available, frequent arterial puncture is mandatory. This requires some technical skill and may occasionally have side effects. So we studied the validity of capillary blood gas analysis which can be performed conveniently compared with arterial blood. Methods : Twenty-four neonates admitted to NICU during April to Aug. 2001 were studied. They were more than two weeks old without indwelling arterial catheters. Thirty-six times, simultaneous arterial, and capillary blood gases were drawn by puncture and the pH, $pCO_2$ and $pO_2$ of each sample was measured. Blood pressure and body temperature was checked before sampling to rule out impaired peripheral circulation. Capillary blood was collected from warmed heels. Results : There was a strong correlation between capillary and arterial pH(r=0.91, P<0.05). The absolute value of the difference between arterial and capillary pH was less than 0.05. Also capillary $pCO_2$ showed correlation with arterial $pCO_2$(r=0.77, P<0.05). Despite a statistically significant correlation between capillary and arterial $pO_2$(r=0.68, P<0.05), the absolute value of the difference was more than 10 mmHg in 92% of cases. Conclusion : Capillary blood gases accurately reflected arterial pH and $pCO_2$ and showed a relative correlation with $pO_2$. Capillary blood gas analysis can be a useful alternative to arterial blood when continuation of the umbilical arterial catheter is no longer available.

• The Journal of Internal Korean Medicine
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• v.38 no.2
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• pp.110-117
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• 2017

Objective: This study was undertaken to examine the effect of Cortex Phellodendri on prostatic urethral pressure and mean arterial blood pressure of rabbits. Methods: To measure prostatic urethral pressure and mean arterial blood pressure, a Mikro-Tip catheter transducer was inserted and positioned in the prostatic urethra and left carotid artery. After a stabilizing period, phenylephrine ($1{\mu}/kg$) was intravenously administered two or three times to increase the urethral pressure and mean arterial blood pressure. Cortex Phellodendri (2.5 mg/kg and 5 mg/kg doses of Cortex Phellodendri extracted from 80% Ethanol) was administered intravenously, followed by phenylephrine, with no time interval between the doses. The urethral pressure and mean arterial blood pressure were then measured to determine whether they had stabilized. Results and Conclusion: Cortex Phellodendri appeared to inhibit phenylephrine-induced increases in prostatic urethral pressure and mean arterial blood pressure.

• Journal of Acupuncture Research
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• v.27 no.3
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• pp.47-57
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• 2010

Experimental Study of Taegye($KI_3$) Taebaek($SP_3$) Draining Acupuncture on the Improvement of Cerebral Blood flow and Arterial Blood Pressure. Objectives : This study was designed to investigate the effects of acupuncture on Taegye($KI_3$) Taebaek($SP_3$) draining and determine the mechanism of action of PCBL by measuring the changes of regional cerebral blood flow (rCBF) and mean arterial blood pressure (MABP) in normal rats. Methods : This study was designed to investigate whether acupuncture on Taegye($KI_3$) Taebaek($SP_3$) draining affect Regional cerebral blood flow(rCBF), Mean arterial blood pressure(MABP) in normal rats. To make manifest whether acupuncture on Taegye($KI_3$) Taebaek($SP_3$) draining was mediated by inhibitor of cyclooxygenase or guanylate cyclase which diate arterial diameter. Results 1. Acupuncture on Taegye($KI_3$) Taebaek($SP_3$) draining significantly increased rCBF but decreased MABP. This result suggests that Acupuncturing on Taegye($KI_3$) Taebaek($SP_3$) draining might significantly increase rCBF by dilating arterial diameter. 2. Acupuncture on Taegye($KI_3$) Taebaek($SP_3$) draining induced increase of rCBF was significantly inhibited by pretreatment with indomethacin (1 mg/kg, i.p.), an inhibitor of cyclooxygenase. 3. This result suggests that the action of Acupuncture on Taegye($KI_3$) Taebaek($SP_3$) draining might be mediated by cyclooxygenase.

• Transactions on Electrical and Electronic Materials
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• v.9 no.1
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• pp.38-43
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• 2008

Using an arterial pressure-volume (APV) model, we performed an analysis of the conventional blood pressure estimation method using an oscillometric sphygmomanometer with computer simulation. Traditionally, the maximum amplitude algorithm (MAA) has been applied to the oscillation waveforms of the APV model to obtain the mean arterial pressure and the characteristic ratio. The estimation of mean arterial pressure and characteristic ratio was significantly affected by the shape of the blood pressure waveforms and the cutoff frequency of high-pass filter (HPF) circuitry. Experimental errors result from these effects when estimating blood pressure. To determine an algorithm independent of the influence of waveform shapes and parameters of HPF, the volume oscillation of the APV model and the phase shift of the oscillation with fast Fourier transform (FFT) were tested while increasing the cuff pressure from 1 mmHg to 200 mmHg (1 mmHg/s). The phase shift between ranges of volume oscillation was then only observed between the systolic and the diastolic blood pressures. The same results were obtained from simulations performed on two different arterial blood pressure waveforms and one hyperthermia waveform.

• 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.

• Proceedings of the KOSOMBE Conference
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• v.1998 no.11
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• pp.177-178
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• 1998

This paper is a study on compensation for error in estimation of mean pressure according to the change of arterial pressure shape. Because arterial pressure shape affects the mean pressure and blood volume which are important factors for measurement of blood pressure(BP), change of arterial pressure shape cause BP measurement error. In order to solve this problem, we add the compensation function C($\alpha$), depending on arterial pressure shape, to mathematical oscillometric model. Consequently, we could accurately estimate the blood pressure by correcting of the error using compensation function.

• Journal of Oriental Neuropsychiatry
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• v.18 no.1
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• pp.185-196
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• 2007

Objective : This experimental Study was designed to investigate the effects of FOENICULI FRUCTUS(FF) on the change of inhibition lactate dehydrogenase(LDH) activity in neuronal cells and cytokines production in serum of cerebral ischemic rats. Method : FOENICULI FRUCTUS(FF)freeze dry powder and FF on the LDH activity in neuronal cells. Changes of FF on the physiological parameters(PaO2, PaCO2, MABP and HR) in crerbral ischemic rats. Effects of FF on the IL-1beta production, $TNF-{\alpha}$ production, $TGF-{\beta}$ production, and IL-10 in serum of cerebral ischemic rats. MCAO :. cytokines production of serum by drawing from femoral arterial blood after MCAO 1 hr. Reperfusion : cytokines production of serum by drawing from femoral arterial blood after reperfusion 1 hr. Results and Conclusion : 1. FF did not inhibit lactate dehydrogenase(LDH) activity in neuronal cells. 2. In serum by drawing from femoral arterial blood after middle cerebral arterial occlusion(MCAO) 1 hr and reperfusion 1 hr, sample group was significantly decreased $IL-l{\beta}$ production compared with control group 3. In serum by drawing from femoral arterial blood after MCAO 1 hr and reperfusion 1 hr, sample group was significantly decreased $TNF-{\alpha}$ production compared with control group. 4. In serum by drawing from femoral arterial blood after MCAO 1 hr and reperfusion 1 hr, sample group was significantly increased $TGF-{\beta}$ production compared with control group. 5. In serum by drawing from femoral arterial blood after reperfusion 1 hr, sample group was significantly increased IL-10 production compared with control group. This results were suggested that FF had inhibitive effect on the brain damage by inhibited LDH activity, $IL-l{\beta}$ and $TNF-{\alpha}$production, but accelerated $TGF-{\beta}$ production and IL-10 production.