• 대한기계학회논문집B
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• 제30권1호
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• pp.87-94
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• 2006

This paper presents the hydrodynamic design and performance analysis method for a miniaturized centrifugal blood pump using three-dimensional computational fluid dynamics (CFD) code. In order to obtain the hydraulically high efficient configuration of a miniaturized centrifugal blood pump for cardiopulmonary circulation, a well-established commercial CFD code was incorporated considering detailed flow dynamic phenomena in the blood pump system. A prototype of centrifugal blood pump developed by the present design and analysis method has been tested in the mock circulatory system. Predicted results by the CFD code agree very well with in vitro hydraulic performance data for a centrifugal blood pump over the entire operating conditions. Preliminary in vivo animal testing has also been conducted to demonstrate the hemodynamic feasibility for use of centrifugal blood pump as a mechanical circulatory support. A miniaturized centrifugal blood pump developed by the hydraulic design optimization and performance prediction method presented herein shows the possibility of a good candidate for intra and extracorporeal cardiopulmonary circulation pump in the near future.

• Journal of Chest Surgery
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• 제12권2호
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• pp.119-126
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• 1979

This is one case report of the extremely rare congenital cardiac malformation, Double-outlet of left ventricle in corrected transposition of great arteries. 11-year-old boy complained acrocyanosis and exertional dyspnea, the parents noticed cyanosis since birth. Physical examination revealed acrocyanosis, clubbed fingers and toes, G-III pansystolic murmur on 2nd and 3rd ICS, LSB. Right heart catheterization revealed significant $O_2$ jump in ventricular level. Right and left ventriculography showed the both catheters arriving in the same ventricle i.e. anterior chamber, morphological left ventricle was in right and anterior position, simultaneous visualization of aorta and pulmonary artery and aorta locating anterior and right side of pulmonary artery. Echo cardiogram surely disclosed interventricular septum. Conclusively it was clarified that the patient has Double-outlet of left ventricle and corrected transposition of great arteries [S.L.D.]. Operation was performed to correct the anomalies under extracorporeal circulation with intermittent moderate hypothermia. Right-sided ventriculotomy disclosed the following findings. 1. Right-sided ventricle was morphological left ventricle. 2. Left-sided ventricle was morphological right ventricle. 3. Right side atrioventricular valve was bicuspid. 4. Left side atrioventricular valve was tricuspid. 5. Aortic valve was superior, anterior and right side of pulmonary valve. 6. Subpulmonary membranous stenosis. 7. Non-committed ventricular septal defect. We made a tunnel between VSD and aorta with Teflon patch so that arterial blood comes through VSD and the tunnel into aorta. After correction the patient needed assisted circulation for 135 min. to have adequate blood pressure. Postoperatively by any means, adequate blood pressure could not be maintained and expired in the evening of operation day.

• Journal of Chest Surgery
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• 제22권6호
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• pp.921-926
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• 1989

The Free fatty acid [FFA] induced massive erythrocyte crenation has been reported in patients undergoing extracorporeal circulation[EGG], suggesting that the crenated cells impair microcirculatory flow and tissue oxygenation during and after the operation. Effect of albumin administration on erythrocyte crenation was examined in 24patients undergoing open heart surgery at the department of Thoracic and Cardiovascular Surgery in the Kyung Hee University Medical Center Between January, 1989 and August, 1989: 8 patients of 24 patients [group A] were given 50 gm albumin, another 8 patients of 24 patients [group B] were g en 26 gm of albumin and the other 8 patients of 24 patients [group C] were not given any albumin as a part of the priming solution. Erythrocyte crenation was almost completely prevented in the patients given 50 gm albumin. Crenated erythrocytes d urging ECC were 3.6* 0.4 % [mean\ulcornerD] of all erythrocytes and 3.1*0.6% after ECC. This was significantly lower than in patients without albumin administration [64.2*9.5% during ECC and 28.7*1.9% after ECC]. But the effect was less striking in the patients given 25 gm albumin, 37.8* 12.0 % during ECC and 27.8*3.9 % after ECC. Maintaining an adequate level of plasma albumin is important in preventing erythrocyte crenation during ECC, improving microcirculatory flow in patients undergoing open heart surgery.

• Journal of Chest Surgery
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• 제49권4호
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• pp.273-279
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• 2016

Background: The use of extracorporeal life support (ECLS) in the setting of cardiopulmonary resuscitation (CPR) has shown improved outcomes compared with conventional CPR. The aim of this study was to determine factors predictive of survival in extracorporeal CPR (E-CPR). Methods: Consecutive 85 adult patients (median age, 59 years; range, 18 to 85 years; 56 males) who underwent E-CPR from May 2005 to December 2012 were evaluated. Results: Causes of arrest were cardiogenic in 62 patients (72.9%), septic in 18 patients (21.2%), and hypovolemic in 3 patients (3.5%), while the etiology was not specified in 2 patients (2.4%). The survival rate in patients with septic etiology was significantly poorer compared with those with another etiology (0% vs. 24.6%, p=0.008). Septic etiology (hazard ratio [HR], 2.84; 95% confidence interval [CI], 1.49 to 5.44; p=0.002) and the interval between arrest and ECLS initiation (HR, 1.05 by 10 minutes increment; 95% CI, 1.02 to 1.09; p=0.005) were independent risk factors for mortality. When the predictive value of the E-CPR timing for in-hospital mortality was assessed using the receiver operating characteristic curve method, the greatest accuracy was obtained at a cutoff of 60.5 minutes (area under the curve, 0.67; 95% CI, 0.54 to 0.80; p=0.032) with 47.8% sensitivity and 88.9% specificity. The survival rate was significantly different according to the cutoff of 60.5 minutes (p=0.001). Conclusion: These results indicate that efforts should be made to minimize the time between arrest and ECLS application, optimally within 60 minutes. In addition, E-CPR in patients with septic etiology showed grave outcomes, suggesting it to be of questionable benefit in these patients.

• Journal of Chest Surgery
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• 제54권2호
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• pp.99-105
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• 2021

Background: The number of heart transplantations (HTx) is increasing annually. Due to advances in medical and surgical support, the outcomes of HTx are also improving. Extracorporeal circulatory life support (ECLS) provides patients with decompensated heart failure a chance to undergo HTx. A medical approach involving collaboration among experienced experts in different fields should improve the outcomes and prognosis of ECLS-bridged HTx. Methods: From December 2003 to December 2018, 1,465 patients received ECLS at Samsung Medical Center. We excluded patients who had not undergone HTx or underwent repeated transplantations. Patients younger than 18 years were excluded. We also excluded patients who received an implantable durable left ventricular assist device before HTx. In total, 91 patients were included in this study. A multidisciplinary team approach began in March 2013 at our hospital. We divided the patients into 2 groups depending on whether they were treated before or after implementation of the team approach. Results: The 30-day mortality rate was significantly higher in the pre-ECLS team group than in the post-ECLS team group (n=5, 18.5% vs. n=2, 3.1%; p=0.023). The 1-year survival rate was better in the post-ECLS team group than in the pre-ECLS team group (n=57, 89.1% vs. n=19, 70.4%; p=0.023). Conclusion: We found that implementing a multidisciplinary team approach improved the outcomes of ECLS-bridged HTx. Team-based care should be adapted at HTx centers that perform high-risk HTx.

• Journal of Chest Surgery
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• 제13권3호
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• pp.186-197
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• 1980

We attempted to evaluate the effectiveness of cold blood potassium cardioplegia [Group B] compared with that of intermittent aortic cross clamp with topical hypothermia [Group A] in each six dogs. The studies were performed under the extracorporeal circulation with moderate hypothermia by using Mongrel dogs. 1. In Group A [6], it was difficult to maintain the temperature below 20?. but in Group B [6], it was possible to maintain the temperature. 2. In blood pressure and myocardial recovery ability, Group B was more excellent than Group A. 3. There was no significant difference in Na+, Ca++ and Cl- between both groups, but in K+ level, Group A was mild decreased and Group B was nearly normal level. 4. In serum LDH level, Group A was higher than Group B, but in SGOT level there was no significance between both groups. 5. On electromicroscopical study, Group A showed severe change in mitochondria, but Group B was nearly normal view. Thus we suggest that cold blood potassium cardioplegia would be more effective than intermittent aortic cross clamp with topical hypothermia for myocardial protection in open heart surgery.

• Journal of Chest Surgery
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• 제13권3호
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• pp.250-255
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• 1980

Myxoma is a benign growth constituting nearly 50% of all primary cardiac tumors. It is important because it can be abolished by surgical therapy and is usually fatal if unrecognized and untreated. Recently a wider use of echocardiogram as the screening test of valve lesions can be expected to increase the number of myxomas found preoperatively. We report a case of left atrial myxoma which was diagnosed by echocardiogram before surgery, and was successfully removed with the aid of extracorporeal circulation. The patient was a 24-year old woman who had suffered from mitral valvular symptoms for 2 months before admission. At operation, a tumor, measuring 5.2 x 4.3 x 4.7 cm, was extremely friable, villous gelatinous mass and it was removed from its origin near the closed fossa ovalis, including its stalk and a portion of the septum. The postoperative course was uneventful. The patient is clinically well and without symptoms of heart disease.

• Journal of Nutrition and Health
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• 제7권4호
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• pp.30-32
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• 1974

Hemoglobinemia is found in hemolytic anemia, paroxysmal nocturnal hemolobinuria and paroxysmal hemoglobinuria. Recently increasing use of extracorporeal circulation in cardiac surgery has stimulated the development of more precise methods for rapidly evaluating the formation and clearance of extracoporeal hemoglobin. A spectrophotometric method of analysis seemed to offer the best solution to the requirements. The method presented is on the basis of hemoglobin derivatives converted to cyanmethemoglobin, and the absorbance is measured in a spectrophotometer at 540 and 680 nm. The blank value ismeasured at 680 nm while the absorbance at 540 nm measures the hemoglobin derivatives. This method estimates all the hemoglobin derivatives such as oxyhemoglobin, carboxyhemoglobin, methemoglobin, sulfhemoglobin and hemialbumin. The method was tested in recovery experiments, which is given table 1. A good degree of correlation was obtained in a comparision with the method described by Crosby and Furth for non-hemolyzed serum. The spectrophotometric technique described offers many advantages in speed and simplicity over the chemical procedure.

• Journal of Chest Surgery
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• 제10권2호
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• pp.250-267
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• 1977

Open heart surgery has been performed on 20 patients, using hemodilution principle under the moderate hypothermia from Dec. 1975 through Aug. 1977 at the Department of Thoracic and Cardiovascular Surgery, Kyungpook National University School of Medicine. All these patients, body surface area ranged from 0.53 to 1.67$M^2$, were divided into two groups as a child group [below 15 yrs] and a adult group[above 15 yrs]. The oxygenator were primed with fresh ACD blood, 5 per cent dextrose, Hartmann`s solution, 15 per cent mannitol, sodium bicarbonate, dexamethasone and antibiotics. The average flow rate was 2.0 L/$M^2$/min. in child group and 2.3L/$M^2$/min. in adult group. The degree of hemodilution in child and adult group was 30.7% and 29.3% respectively. The minimal value of rectal temperature was $30.84{\pm}0.7^{\circ}C.$, in child group and $30.0{\pm}1.5^{\circ}C.$, in adult group. We studied the changes of hemodynamic status, blood components, electrolyte, acid-base status. blood lactic acid and urine output during and after cardiopulmonary bypass.

• Journal of Chest Surgery
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• 제19권2호
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• pp.243-249
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• 1986

Thirty-two cases of tetralogy of Fallot corrected totally using extracorporeal circulation in this department are presented during the period from April 1983 to Feb. 1986. Types of right ventricular outflow tract obstruction were a case of pulmonic valvular stenosis, 3 cases of infundibular stenosis, and 28 cases of combined type. There were associated anomaly such as 3 cases of pulmonary arterial hypoplasia, 7 cases of atrial septal defect, a case of left superior vena cava, and 2 cases of right side aortic arch. Transannular patch for right ventricular outflow tract reconstruction was necessary in 12 cases. Operative death was 6 cases and late death was a case, but other remaining cases followed up over 2 months carried out normal life.