• 대한한방내과학회지
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• 제19권1호
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• pp.157-167
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• 1998

Background and Purpose : Cerebrovascular reactivity(CVR) can be estimated by measuring the change of cerebral blood flow that occurs during vasostimulation. To estimate the cerebrovascular reactivity, we investigated the change of flow velocity of the middle cerebral artery(MCA) during hyperventilation and hypoventilation with the transcranial doppler. So we studied whether the CVR measured by this method could show a significant difference between the normal and the cerebral infarction subjects and whether the CVR may decrease with age in normal subjects. Methods : Using transcranial doppler, we measured the mean velocity(Vm), the pulsatility index(P.I.) at the resting state, the end of breath-holding and the end of hyperventilation in 36 normal and 10 cerebral infarction subjects, so we calculated the percentile change of mean velocity(%${\Delta}$Vm) and P.I.(%${\Delta}$P.I.) after the vasostimulation. We estimated the change of Vm, P.I., %${\Delta}$Vm and %${\Delta}$P.I. by the age group and compared those parameters between the age-matched normal control and cerebral infarction subjects. Results : The Vm in MCA significantly decreased with age(p<0.05), but there was no significant difference in Vm and P.I. between normal and cerebral infarction subjects. The %${\Delta}$Vm and %${\Delta}$P.I. in response to hyperventilation significantly decreased with age in MCA and there was significant difference in $%{\Delta}Vm$ of MCA after breath-holding between the normal and cerebral infarction subjects. Conclusion : The breath-holding and hyperventilation tests could be non-invasive and useful methods in estimation of the cerebrovascular reactivity and could be applied in the basal and follow-up evaluation of the cerebrovascular reserve of the ischemic stroke patients.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제33권5호
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• pp.375-384
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• 2011

Purpose: The advent of microsurgical technique and instruments, particularly in the field of perforator flap and supermicrosurgery, which have expanded the scope of microsurgery. However, supermicroanastomosis without any compression, tension, or distortions must be achieved to reach successful outcomes. Small-caliber vessels, such as those with an internal diameter less than 0.2 mm, are susceptible to inadvertent twisting of the anastomosis. In this study, using the superficial inferior epigastric artery (SIEA)-based flap model in Sprague-Dawley (SD) rats, we evaluated the acceptable limits of twisting effects on supermicroanastomotic sites. Methods: A total of 20 supermicroanastomoses were performed using the SIEA-based flap model in 10 male SD rats, 10-weeks-of-age, weighing 300~350 g. Rats were divided into five groups of two with four flaps as follows: 1) sham, 2) control group with end to end SIEA arterial supermicroanastomosis, 3) experimental I (EA1) with $90^{\circ}$ twisting, 4) experimental II (EA2) with $180^{\circ}$ twisting, and 5) experimental III (EA3) with $270^{\circ}$ twisting of the supermicroanastomosis. Each SIEA was anastomosed using six 11-0 $Ethilon^{(R)}$ (Ethicon Inc. Co., NJ, USA) stitches except in the sham group where the SIEA was only clamped with Supermicro vascular $clamps^{(R)}$ (S&T, Neuhausen, Switzerland) for 20 minutes. Results: The anastomosed arterial patency showed no remarkable changes according to doppler waveforms measured with a Smardop 45 Doppler System (Hadeco Inc., Kawasaki, Japan). The pulsatility index (PI) was increased at postoperative day 10 in the EA2 and EA3 groups, and the resistance index (RI) showed no statistically significant difference between preoperative and postoperative values at 10 days. Histologic specimens from the EA3 group showed increased tunica media necrosis, convolution of the internal elastic lamina, densely packed platelets, fibrin, and erythrocytes. Flap viability and anastomosed vessel patency were not significantly affected by the degree of arterial twisting in this study, other than in the EA3 group where minor effects on arterial patency of the microanastomoses were encountered. Conclusion: It appears that minor twisting on small caliber arteries, used in supermicroanastomoses, can be tolerated. However, twisting should be avoided as much as possible, and more than $180^{\circ}$ twisting must be prevented in clinical practice.

• Journal of Chest Surgery
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• 제49권3호
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• pp.145-150
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• 2016

Background: Extracorporeal circulation (ECC) can induce alterations in blood viscoelasticity and cause red blood cell (RBC) aggregation. In this study, the authors evaluated the effects of pump flow pulsatility on blood viscoelasticity and RBC aggregation. Methods: Mongrel dogs were randomly assigned to two groups: a nonpulsatile pump group (n=6) or a pulsatile pump group (n=6). After ECC was started at a pump flow rate of 80 mL/kg/min, cardiac fibrillation was induced. Blood sampling was performed before and at 1, 2, and 3 hours after ECC commencement. To eliminate bias induced by hematocrit and plasma, all blood samples were adjusted to a hematocrit of 45% using baseline plasma. Blood viscoelasticity, plasma viscosity, hematocrit, arterial blood gas analysis, central venous $O_2$ saturation, and lactate were measured. Results: The blood viscosity and aggregation index decreased abruptly 1 hour after ECC and then remained low during ECC in both groups, but blood elasticity did not change during ECC. Blood viscosity, blood elasticity, plasma viscosity, and the aggregation index were not significantly different in the groups at any time. Hematocrit decreased abruptly 1 hour after ECC in both groups due to dilution by the priming solution used. Conclusion: After ECC, blood viscoelasticity and RBC aggregation were not different in the pulsatile and nonpulsatile groups in the adult dog model. Furthermore, pulsatile flow did not have a more harmful effect on blood viscoelasticity or RBC aggregation than nonpulsatile flow.

• 대한의생명과학회지
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• 제12권4호
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• pp.375-383
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• 2006

The physiological responses following stress are different in individual or personality. We performed this study to clarify gender differences in influences of noise stress on physiological factors. 70 healthy subjects, which was divided man (n=30) and woman (n=40) groups, were exposed to 85 decibels of excavator noise for 15 minutes. Cardiac factors such as heart rate (HR), systolic and diastolic blood pressures (SBP and DBP, respectively), and heart rate-systolic pressure product (RPP) were determined. Transcranial Doppler ultrasound (TCD) was used to measure mean blood flow velocity (Vm), pulsatility index (PI), and resistance index (RI) in the middle, anterior and posterior cerebral arteries (MCA, ACA and PCA, respectively) before and during noise exposure. Cortisol level and hematological variables were also measured before (baseline) and immediately after the end of noise exposure. In the both groups HR, SBP, and RPP significantly decreased during noise exposure (P<0.05) but not significantly different between two groups (P>0.05). Vms of three cerebral arteries in man group decreased, whereas Vm of PCA in woman group fell during noise exposure (P<0.05). Vm, PI and RI in MCA and ACA during noise exposure were low in man group compared with woman group (P<0.05). Vm of PCA was low, whereas PI and RI of PCA were high in man group compared with woman group during noise exposure (P<0.05). Total leukocyte and red blood cell (RBC) counts slightly decreased during noise exposure but not significant (P>0.05). Levels in hematological variables decreased but not significant changed following noise exposure. Decreased rate of total leukocyte in man group was higher (P<0.05). Cortisol levels in the both groups decreased immediately after the end of noise exposure, while the decreased rate in man group was greater than that in woman group (p<0.05). These findings indicate that a transient exposure to experimental excavator noise may cause decreased changes in cardiac factors, cerebral hemodynamics and cortisol levels and the changes may be greater in men than in women.

• 대한한방내과학회지
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• 제35권1호
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• pp.24-36
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• 2014

Objectives : This study was performed to evaluate the effects of moxibustion on cerebral blood flow, peripheral blood flow and blood pressure. Methods : We designed a randomized, cross-over study that included 20 healthy, male volunteers who were randomly assigned to one of two groups (the moxibustion group or the control group). The initial trial was followed by a washout period of one week before the groups were switched and the trial repeated. The cerebral blood flow and peripheral blood flow of the volunteers in both groups were measured by mean velocity (Vm), peak systolic velocity (Vs), pulsatility index (PI), perfusion units (PU) and mean blood pressure (BP) before the intervention (baseline), 30 minutes after the intervention, and again 60 minutes after the intervention. Results : 1. The Vm increased significantly in the moxibustion group. The Vs also constantly increased in moxibustion group, but there was no significant difference. 2. The PI decreased significantly in the control group at 0-30 minutes and in the moxibustion group at 30-60 minutes. 3. The PU constantly decreased in moxibustion group. In control group, the PU decreased at 30 minutes and increased slightly at 60 minutes. 4. The mean blood pressure did not show any significant difference between the two groups. Conclusions : This study shows that moxibustion at CV12 increased the cerebral blood flow. Based on this result, we can suggest that moxibustion at CV12 might be helpful in improving the functional recovery of stroke patients. However, further research needs to be conducted on a larger numbers of subjects in order to confirm these effects.

• 대한한방내과학회지
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• 제25권3호
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• pp.418-426
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• 2004

Objectives : This study was designed to research whether transcranial doppler ultrasound(TCD) can yield a suitable diagnosis or prognosis for dizziness. Methods : To evaluate the blood flow, we measured the mean velocity(Vm), peak systolic velocity(Vs) and pulsatility index(PI) of the middle cerebral artery(MCA), vertebral artery(VA) and basilar artery(BA) in 54 dizziness patients and 44 normal subjects. To investigate the difference between dizziness patients and normal subjects, we selected 54 dizziness patients diagnosed normal by Brain MRI, and 44 normal subjects who did not have any symptoms of hyperlipemia, hypertension, diabetes melitus, heart disease, or smoking, diagnosed normal by Brain MRI. 30-69 year olds were divided into 30-49 year olds, 50-59 year olds and 60-69 year olds. Results : In normal subjects, there was a significantly higher Vm, Vs in the MCA and BA, and Vs in the VA of female subjects, and there was a significant difference in PI in the MCA and BA increasing with age. In comparison with normal subjects, dizziness patients had a significantly lower Vm in the BA. Male dizziness patients had significantly lower PI in the MCA. 30-49 year olds had significantly lower Vm in the BA. Conclusions : The significant difference in blood flow velocities in the BA between dizziness patients and normal subjects suggests that dizziness is related to blocking of blood flow in the BA and that diagnosis and prognosis can be made through TCD. More detailed study of dizziness patients will be needed.

• 생명과학회지
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• 제19권11호
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• pp.1658-1665
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• 2009

15분간의 1회성 유산소 운동 시 염증성 표지자들의 변화와 여러 생리학적 변수들 간의 상관관계를 밝히기 위해 30명의 젊은 남성을 대상으로 연구를 실시하였다. 운동 후 인터루킨-6(IL-6) 농도, 평균적혈구 혈색소 농도, 심박수, 수축기혈압, 중대뇌동맥 박동지수(PI) 및 저항지수(RI)는 운동 전 보다 증가하였다. 총백혈구수, 혈소판 수, 저밀도콜레스테롤은 운동후 약간 감소되는 경향이 있었다. 운동 전 IL-6농도와 수축기 혈압 간에 양의 상관성이, 운동 후 IL-6농도와 PI 및 RI 사이에 각각 양의 상관관계를 보였다. 운동 후 시기에 고민감도 C-반응단백 농도와 수축기혈압 또는 심박수와 각각 음의 상관성을 보였고, 운동 전 시기에 활성산소 농도와 수축기혈압, 이완기 혈압, 또는 심박수와 각각 양의 상관성을 나타내었다. 운동후 활성산소 농도와 중대뇌동맥의 혈류속도 간에 음의 상관성이 있었다. 운동 전 적혈구 지수(적혈구 수, 평균적혈구 용적, 평균적혈구혈색소, 평균적혈구 혈색소 농도)와 IL-6농도 사이에 반비례적 상관성이 있었다. 운동 후 활성산소 농도와 운동후 총백혈구수, 림프구수, 단구수 간에 음의 상관관계가 있었다. 운동 전, 마그네슘 농도와 IL-6, 고민감도 C-반응단백, 활성 산소 농도 사이에 음의 상관성이 있었다. 그리고 그 외 일부 생화학적 변수 및 전해질 농도와 염증성 표지자들 사이에 양혹은 음의 상관성이 있었다. 이러한 결과들은 짧은 시간 동안의 1회성 경도 유산소 운동역시 염증성 표지자들과 혈액변인 사이에 유의한 상관관계를 미칠 수 있으나 향후 좀 더 많은 연구를 통해 일회성 혹은 규칙적인 운동에 따른 성별 간 혹은 연령대별 생리학적 차이를 함께 규명할 필요 역시 있다.