• Journal of Chest Surgery
• /
• v.40 no.4 s.273
• /
• pp.273-279
• /
• 2007

Background: We evaluate the efficacy of ultra-hydrophilic coated bypass circuits in comparison with uncoated bypass circuits in a porcine cardiopulmonary bypass model. Material and Method: Normothermic cardiopulmonary bypass was peformed in 10 anesthetized pigs via the left atrium and ascending aorta with a centrifugal biopump. Ultra-hydrophilic coated bypass circuits wore used in 5 pigs (the study group) and uncoated bypass circuits were used for the control group. Platelet counts and platelet aggregation tests were peformed. The thrombin-antithrombin(TAT) complex level and total protein level were evaluated. Result: There were no significant changes En the platelet counts and aggregation ability of both groups. The TAT complex levels were not different between the two groups. The total protein level was significantly lower in the control group after cessation of cardiopulmonary bypass. Conclusion: The clinical effects of ultra-hydrophilic coating circuits were not remarkable, in terms of reducing inflammatory reaction and protection of platelet function. However, the effect of protection for blood protein adsorption might be acceptable.

• Journal of Chest Surgery
• /
• v.33 no.10
• /
• pp.785-791
• /
• 2000

Left ventricular dysfuction is common in immediate postoperative periods after surgical correction of heart diseases with chronic left ventricular volume overload. We speculated postoperative changes of left ventricular volume and unction in patients with patent ductus osus(PDA) who had underwent surgical repair at ages older than 16 years. Factors influencing postoperative left ventricular volume and function were also analyzed. Material and Method: From August 1989 to August 1999 thirty-siz adult patients with PDA 28 females and 8 males. were enrolled in this study. Their age ranged from 16 years to 57 years(mean :32 years). Types of surgical repair were division with primary closure in 22, division with patch closure in 6, internal obliteration using cardiopulmonary bypass in 4 and ligation in 4. Aortic clamping was combined during surgical repair in 22(61%) and cardiopulmonary bypass was used in 8(22%) Two-dimensional echocardiography studies were performed in 34(94%) preoperatively and in 25(66%) immediate postoperatively to assess postoperative changes of left ventricular internal dimensions. left ventricular volume and ejection fraction. Duration of postoperative follow-up ranged from 1 month to 99 months (mean:22 months) and 10 patients underwent 16 echocardiographic evaluation during this period Result : Preoperative and postoperative left ventricular systolic dimensions(LVIDs) were 42$\pm$8.0mm and 42$\pm$8.3mm left ventricular diastolic dimensions(LVIDd) were 64$\pm$10.0mm and 56$\pm$7.4mm left ventricular end systolic volumes(LVESV) were 62$\pm$19cc (z=1.87$\pm$0.06) and 59$\pm$24cc(z=1.78$\pm$0.08) left ventricular end diastolic volumes(LVEDL) were 169$\pm$40cc(z-1.17$\pm$0.1) and 112$\pm$29cc(z=0.85$\pm$0.1) and ejection fractions(EF) were 66$\pm$6.7% and 48$\pm$12.6% respectively. There were statistically significant differences between preoperative and postoperative values in LVDIDd(p=0.001) LVEDV(p=0.001) and EF(p=0.0001) while no significant difference is LVIDs and LVESV. Postoperative depression of ejcection fraction was significantly related with z-score of preoperative LVESV and LVEDV by univariateanalysis while LVEDV only was significant risk factor for postoperative LV dysfunction by multiple regressioin analysis ($\Delta$LVEF=-13.3-4.62$\times$LVEDV(z), p=0.001) During the follow-up periods ejection fractions become normalized in all except one patients. Conclusion ; Left ventricular function is usually deteriorated after the surgical correction of PDA in adult age and preoperative LVEDV is a major determinant of postoperative LV function.

• Journal of Chest Surgery
• /
• v.31 no.1
• /
• pp.32-39
• /
• 1998

High-dose aprotinin(Hammersmith regimen) has been widely used for years to control postoperative bleeding and reduce blood consumption in cardiac surgery but had known to cause some side-effects and had disadvantage in cost-effectiveness. The prospective controlled study of 33 patients undergoing cardiopulmonary bypass was performed to evaluate the efficacy for reducing postoperative bleeding and unfavorable effects of low-dose aprotinin. The level of hemoglobin and platelet in the blood and the amount of postoperative bleeding were assessed preoperatively, and postoperatively for the study of hemostatic function. The level of BUN and serum creatinine in the blood, levels of urine creatinine, total protein, albumin, alpha-1-microglobulin and creatinine clearance were assessed before and after the operation for the study of renal function. The aprotinin group had a significant reduction in chest tube drainage; 243$\pm$ 123 ml versus 406$\pm$303 ml(P=0.037) during 6 hours immediate-postoperatively, 494$\pm$358 ml versus 869$\pm$570 ml(P=0.045) during 24 hours postoperatively. The ratio of alpha-1-microglobulin/creatinine and microalbumin/creatinine in the urine were slightly increased in the aprotinin group postoperatively in comparison with the control group but there were no statistically significant difference(55$\pm$23 versus 24$\pm$10 in the alpha-1-microglobulin/creatinine, 56$\pm$19 versus 38$\pm$25 in the microalbumin/creatinine at post- operative 3rd day). There were no significant difference between two groups in other parameters of renal function, too. This study showed that low-dose aprotinin is an effective means of reducing postoperative bleeding without inducing significant renal dysfunction.

• Clinical and Experimental Pediatrics
• /
• v.52 no.7
• /
• pp.752-755
• /
• 2009

It is well known that hemodynamic load is one of the most important determinants of cardiac structure and function. Circadian variations in blood pressure (BP) are usually accompanied by consensual changes in peripheral resistance and/or cardiac output. In recent years, reduction in circadian variations in BP and, in particular, loss of nocturnal decline of BP were observed in hypertensive patients with left ventricular hypertrophy (LVH). The patients with only a slight or no loss of nocturnal decline of BP were considered "non-dippers". Regression of LVH was observed after prolonged antihypertensive therapy. Restoration of the circadian rhythm of BP was also observed. However, the classification of patients into "dippers" and "non-dippers" is arbitrary and poorly standardized and repeatable, and in the recent studies, most hypertensive patients with LVH were "dippers". Therefore, we should be particularly cautious about the conclusions drawn using this index. On the other hand, reduced activity of low-pressure cardiopulmonary baroreceptors and impaired day-to-night modulation of autonomic nervous system activity were observed in patients with only LVH. Therefore, alterations in cardiac structure may impair BP modulation. On the other hand, the reverse can also be trueprimary alterations in BP modulation, through a persistently elevated afterload, can increase cardiac mass. Thus, the interrelationship between cardiac structure and BP modulation is complex. Hence, new and more specific methods of evaluating circadian changes in BP are needed to better clarify the abovementioned reciprocal influences.

• Clinical and Experimental Pediatrics
• /
• v.61 no.2
• /
• pp.59-63
• /
• 2018

Purpose: Cardiomyopathy is becoming the leading cause of death in patients with Duchenne muscular dystrophy because mechanically assisted lung ventilation and assisted coughing have helped resolve respiratory complications. To clarify cardiopulmonary function, we compared cardiac function between the home ventilator-assisted and non-ventilator-assisted groups. Methods: We retrospectively reviewed patients with Duchenne muscular dystrophy from January 2010 to March 2016 at Gangnam Severance Hospital. Demographic characteristics, pulmonary function, and echocardiography data were investigated. Results: Fifty-four patients with Duchenne muscular dystrophy were divided into 2 groups: home ventilator-assisted and non-ventilator-assisted. The patients in the home ventilator group were older ($16.25{\pm}1.85years$) than those in the nonventilator group ($14.73{\pm}1.36years$) (P=0.001). Height, weight, and body surface area did not differ significantly between groups. The home ventilator group had a lower seated functional vital capacity ($1,038{\pm}620.41mL$) than the nonventilator group ($1,455{\pm}603.2mL$). Mean left ventricular ejection fraction and fractional shortening were greater in the home ventilator group, but the data did not show any statistical difference. The early ventricular filling velocity/late ventricular filling velocity ratio ($1.7{\pm}0.44$) was lower in the home ventilator group than in the nonventilator group ($2.02{\pm}0.62$. The mitral valve annular systolic velocity was higher in the home ventilator group (estimated ${\beta}$, 1.06; standard error, 0.48). Patients with Duchenne muscular dystrophy on a ventilator may have better systolic and diastolic cardiac functions. Conclusion: Noninvasive ventilator assistance can help preserve cardiac function. Therefore, early utilization of noninvasive ventilation or oxygen may positively influence cardiac function in patients with Duchenne muscular dystrophy.

• Tuberculosis and Respiratory Diseases
• /
• v.39 no.6
• /
• pp.511-516
• /
• 1992

Background: It is well known that cigarette smoking is the risk factor of lung cancer, chronic obstructive pulmonary disease and ischemic heart disease. But there are few reports about the immediate effect of cigarette smoking on the cardiopulmonary functions. The serum level of carbon monoxide increases during cigarette smoking. It is known that carbon monoxide increases respration rate, heart rate and cardiac output, with decrease in maximal oxygen consumption. So we have studied to determine the immediate effects of cigarette smoking on the cardiopulmonary function during exercise. Method: Thirteen healthy smoking male subjects were included in this study. Each subject was undertaken pulmonary function test and incremental exercise test on two separate days, one without smoking (control) and the other after smoking three cigarettes per hour for five hours. The order of the two tests was randomized. Results: 1) The mean age of the subjects was $25{\pm}4.9$ year-old and the mean smoking history was $6{\pm}5$ pack years. 2) The mean blood level of carbon monoxide on the smoking day was higher than that on the nonsmoking day ($5.97{\pm}1.34%$ vs. $1.45{\pm}0.83%$; p<0.01). 3) The mean maximal oxygen consumption on the smoking day was lower than that on the nonsmoking day ($2.09{\pm}0.32$ L/min vs. $2.39{\pm}0.32$ L/min; p<0.05). 4) The mean anaerobic threshold on the smoking day was lower than that on the nonsmoking day ($1.33{\pm}0.24$ L/min vs. $1.53{\pm}0.20$ L/min; p<0.05). 5) The mean heart rate at rest on the smoking day was higher than that on nonsmoking day ($84.38{\pm}11.06$ beats/min vs. $75.46{\pm}5.83$ beats/min; p<0.05). But the means of maximal heart rate on both days were not different. 6) The pulmonary function tests were similar on both days. Conclusion: There was no change in pulmonary function test, but the maximal oxygen consumption and anaerobic threshold were decreased on the smoking day. So it was concluded that cigarette smoking impaired the cardiovascular functions immediately during exercise.

• Journal of Chest Surgery
• /
• v.25 no.3
• /
• pp.232-239
• /
• 1992

Acute renal failure is a well known serious complication following open heart surgery and is associated with a significant increase in morbidity and mortality rate. From 1984 to 1990, 33 patients who had acute renal failure following cardiopulmonary bypass received renal replacement therapy. PD[Peritonial dialysis] was employed in 11 patients and CAVH[continous arteriovenous hemofiltration] was employed in 22 patients. Their age ranged from 3 months to 64 years[mean 25.5$\pm$7.8 years]. The disease entities included congenital cardiac anomaly in 18, valvular heart disease in 15 and aorta disease in 2 cases. Low cardiac output was thought as a primary cause of ARF except two redo valve cases who showed severe Aemolysis k depressed renal function preoperatively. Mean serum BUN and creatinine level at the onset renal replacement therapy were 65$\pm$8 mg/dl and 3.5$\pm$0.4 mg/dl respectively, declining only after reaching peak level 7&10 days following the onset of therapy. Overall hospital mortality was 72.7%[24/33]; 81%[9/11] in PD group and 68.2% [15/22] in CAVH group respectively. The primary cause of death was low cardiac output & hemodynamic depression in all the cases. The fatal complications included multiorgan failure in 7, disseminated intravascular coagulation and sepsis in 6, neurologic damage in 4 and mediastinitis in 3 cases. No measurable differences were observed between CAVH and PD group upon consequence of acute renal failure and disease per se. The age at operation, BUN/Cr level at the onset of bypass and highest BUN/Cr level and the consequence of low output status were regarded as important risk factors, determining outcome of ARF and success of renal replacement therapy. Thus, we concluded that althoght the prognosis is largely determined by severity of low cardiac output status and other organ complication, early institution of renal replacement therapy with other intensive supportive measures could improve salvage rate in established ARF patients following CPB.

• Journal of Biomedical Engineering Research
• /
• v.37 no.5
• /
• pp.153-160
• /
• 2016

This study proposes an algorithm for removal of CPR artifact in order that automated external defibrillator (AED) can effectively diagnose ECG rhythm during cardiopulmonary resuscitation (CPR). Current AED required to interrupt chest compression for reliable rhythm analysis to avoid the effect of artifacts produced by CPR. However even temporarily interruption of chest compression during CPR adversely affects the probability of restoration of spontaneous circulation (ROSC) and survival after the delivery of the shock. Therefore, we proposed a method for removal of CPR artifacts using least mean square (LMS) filter. The removal of the CPR artifacts would enable compressions to continue during AED rhythm analysis, thereby increasing the likelihood of resuscitation success. It was tested on 31 segments of shockable and 300 segments of non-shockable ECG signals recorded from three pigs during CPR. In the result, sensitivity (Se) and specificity (Sp) analysis on the test segments showed values of Se = 3.2%, Sp = 66.0% and Se = 96.8%, Sp = 98.7% in the case of unfiltered and filtered signals during CPR. In conclusion, it was shown that the proposed method can be a useful tool to exactly diagnose the ECG rhythm during the CPR.

• Journal of computational fluids engineering
• /
• v.21 no.1
• /
• pp.103-109
• /
• 2016

With the rapid increase in the number of patients with cardiopulmonary diseases, more cardiopulmonary circulatory assist devices are also needed. These devices can be employed when heart and/or lung function poorly. Due to the critical role they take, these devices have to be designed optimally from both mechanical and biomechanical aspects. This paper presents the CFD results of a baseline model of a centrifugal blood pump for the ECMO condition. The details of flow characteristics of the baseline model together with the performance curves and the modified index of hemolysis(MIH) are investigated. Then, the geometry of baseline impeller and the volute are modified in order to improve the biomechanical performance and reduce the MIH value. The numerical simulations of two cases represent that when impeller radius and prime volume decrease the MIH value also decreases. In addition, the modified geometry shows more uniform pressure distribution inside the volute. The findings provide valuable information for further modification and improvement of centrifugal blood pumps from both mechanical and biomechanical aspects.

• Journal of the Institute of Electronics Engineers of Korea SC
• /
• v.45 no.5
• /
• pp.35-43
• /
• 2008

In this study we confirmed for the cardiopulmonary ability improvement of the cycling exercise which uses a target heart beat. Consequently, we looked the resting systolic blood pressure down at 2.98% and THBI(Total Heart Beat Index) also decrements at 7.59%. But, increase of $VO_2$ max and PTT(Pulse Transit Time)were each point 24.60% and 4.92%. Increase of $VO_2$ max showed the growth of stroke volume by myocardial development. The increase of a stroke volume induces the decrease of Heart rate. The blood pressure was reduced also though the blood of many quantity was supplied at the artery. The reason is the phenomenon to be due to by an elasticity increase of the artery. We found out it through the decrease of PTT. So the cycling exercise to use consequently the target heart beat will become big aid at the health care.