• Title/Summary/Keyword: pulmonary artery perfusion pressure

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An Assessment of Allograft Function in Canine Single Lung Transplantation (일측 폐이식 실험견에서 이식폐의 기능 평가연구)

  • 박창권
    • Journal of Chest Surgery
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    • v.28 no.12
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    • pp.1096-1106
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    • 1995
  • We experienced 7 cases of left single lung transplantation in 14 mongrel dogs and analyzed graft lung function by hemodynamics, blood gas analysis, chest X-ray, biopsy and perfusion lung scan. We performed right pulmonary artery cuff[PA cuff for analysis of graft lung function in 3 cases. The donor lungs were flushed with modified Euro-Collins solution[n=3 or low potassium dextran glucose solution[n=4 and preserved for 4 to 5 hours[n=4 or 24 hours[n=3 at 10o C and implanted to the dogs with similar weight . Assessment of left graft lung was done by occluding the right pulmonary artery for 10 minutes using PA cuff. Assessment for graft lung function was done immediately after an operation and after 3 days, 7days and 3 weeks postoperatively. Four dogs survived for 3days, 7days[2 cases and 3 weeks respectively. Other three dogs expired within 3 hours of reperfusion. Immediate perfusion scans of left lung in four survived dogs after reperfusion were 42.1%, 36% , 11% and 5.9% respectively, and another dog with 4.8% perfusion to left lung was dead due to left atrial thrombi after 3 hours reperfusion. In one case among three acute rejections follow-up perfusion scan was done on 3rd and 11th postoperative day and the result decreased from 36% perfusion immediate postoperatively to 21% and 15% respectively. Three expired dogs postoperatively couldn`t tolerate occlusion of right pulmonary artery with above 40 mmHg of mean pulmonary artery pressure. On the other hand, three survival dogs postoperatively tolerated occlusion of right pulmonay artery with less than 30 mmHg of mean pulmonary artery pressure. and one dog couldn`t tolerate same procedure immediate postopertively but in 2 hours reperfusion later tolerated with 29 mmHg of mean pulmonary artery pressure.In conclusion we couldn`t compare the effect of two flushing solutions but low potassium dextran glucose solution showed relatively safe preservation effect in cases with preservation of more than 20 hours. Also canine left single lung transplantation model with PA cuff indicated useful method for the assessment of graft lung function with effect of lung preservation.

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Inhibitory Effect of Enalapril in Combination with Ginkgo biloba Extract (EGb 761) on the Monocrotaline-induced Pulmonary Hypertension Rats (Monocrotaline에 의해 유발된 폐고혈압 흰쥐에 있어 Enalapril 및 Ginkgo biloba Extract(EGb 761)의 병용 투여시 억제효과)

  • 이영미;안형수;임세진;안령미
    • YAKHAK HOEJI
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    • v.43 no.4
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    • pp.487-493
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    • 1999
  • Effects of Ginkgo biloba extract (EGb 761) on the anti-pulmonary hypertensive action of enalapril were evaluated in rats. Pulmonary hypertension was induced by monocrotaline treatment (60mg/kg, i.p.) in normotensive rats. In the systolic pulmonary artery pressure, the control group was 33$\pm$2 mmHg, comparing to the normal group of 19$\pm$1 mmHg. That of enalapril group(20mg/kg/day, p.o.) was 26$\pm$2 mmHg. In the isolated lung preparation, acetylcholine, which was endothelium dependent vasodilator, induced the decrease of pulmonary artery perfusion pressure(-2.0$\pm$0.7 mmHg) in normal group, but the increase of that of 3.4$\pm$0.6 and 3.0$\pm$0.9 mmHg in control and enalapril group, respectively. And that of the combined group was -0.5$\pm$0.2 mmHg. In the isolated pulmonary artery, acetylcholine(10-5M) induced the relaxation of 65$\pm$6% in normal group, but 15 and 8% in control and enalapril group, respectively. And that of the combined group was resulted 55$\pm$2%. These results suggested that co-administration of Ginkgo biloba extract(EGb 761) potentiated the anti-pulmonary hypertensive effects of enalapril through the increase of pulmonary vasodilation due to the protection of endothelial cell by antioxidant action of Ginkgo biloba extract (EGb 761).

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Lung Preservation Study for Above 20 Hours of LPDG Solution in Canine Lung Allotransplactation (폐이식 실험견에서 LPDG용액을 이용한 20시간 이상 폐보존효과 관찰)

  • Park, Chang-Gwon;Gwon, Geon-Yeong;Yu, Yeong-Seon
    • Journal of Chest Surgery
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    • v.30 no.10
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    • pp.949-960
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    • 1997
  • Background. Limited ischemic tolerance of the lung has remained one of the factors that limits the expansion of pulmonary transplantation as a treatment for end-stage pulmonary disease. Numerous studies on safe long term preservation for lung transplantation has been performed for the purpose of developing ideal preservation solution with extracellular type or intracellular type solutions. In this. study, we examined the efficacy of L DG solution in lung preservation longer than 20 hours by comparison with modified Euro-Collins solution. Iwethods. Thirty-(our adult mongrel dogs were divided into two groups. Donor lungs were flushed with LPDG solution(n=9) or modified Euro-Collins(MEC) solution(n=8) and stored for 24 hours at 1$0^{\circ}C$. All donor lungs were perfused through the pulmonary arteries with solutions containing prostaglandin El and verapamil. Left canine lung allotransplantations wereperformed. Assessment(hemodynamic indices and arterial blood gas analysis) of left implanted lung was made by occluding the right pulmonary artery for ten minutes using pulmonary artery Cuff. Assessment was repeated at the interval of 30 minutes, one hour, and two hours later after reperfusion and then chest X-ray, computed tomogram and lung perfusion scan were obtained. In survival dogs follow-up studies were done with assessment with chest X-ray, computed tomogram of the chest and lung perfusion scan on 7th day postoperatively. After preservation above 20 hours, pathological examinations for ultrastructural findings on right lung were performed in each group. Results. With respect to arterial oxygen tension, LPDG group was superior to MEC but there was no statistical significance for 2 hours after reperfusion. Mean pulmonary artery pressure was less increased(p < 0.05) and cardiac output higher(p <0.05) than MEC group until 2 hours after reperfusion. After 2 hours of reperfusion, both groups showed transplanted lung function deteriorated gradually. Perfusion scan of the transplanted lung in LPDG group showed better perfusion rate in immediate post-reperfusion, 3 days and 7 days later respectively but there was no statistical significance and corelation with PaO2 and computed tomoRravhic views. In scanning electron microscopy of pulmonary artery after preservation, LPDG group relatively shows less irregular protrusion of the inner surface of endothelial cell of poulmonary artery than MEC group. Conclusions, e concluded that LPDG solution can offer safe lung preservation above 20 hours with adequate immunosuppressive therapy and prevention of the infection.

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Animal Experiment of the Pneumatic Ventrivular Assist Device (공압식 심실 보조기의 동물실험)

  • Park, Seong-Sik;Kim, Sam-hyun;Seo, Pil-won;Choi, Chang-hyu;Lee, Sang-hoon;Lee, Hyuk-soo;Hwang, Seung-ok;Ahn, Hyuk
    • Journal of Chest Surgery
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    • v.32 no.12
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    • pp.1065-1077
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    • 1999
  • Background : Ventricular assist devices(VADs) are being used for patients in postcvardiotomy cardiogenic shock status bridge to cardiac transplant settings and in post-myocardial infarction cardiogenic shock. The VAD which was developed at the Deparment of medical engineering in Dankook University College of Medicine was a pneumatically driven device and can maintain pulsatile flow. The goal of this study is to develop animal experimental models using the VAD and to clarify the reliability and hemodynamic property adequacy of end organ perfusion durability and severity of thrombotic-hemolytic tendency of the device. Material and Method : The pneumatic VAD was applied to 8 adult female lambs, We examined some hemodynamic parameters such as arterial blood pressure pulmonary capillary wedge pressure(pcwp) pulmonary artery pressure(PAP) left atrial pressure hour urine output cardiac index VAD flow EKG to determine the reliability of the VAD and hemodynamic compatibility of the experimental animals within 24 hours of experiment. We also observed the end organ perfusion durability of the VAD and thrombotic-hemolytic property of the VAD after 24 hours of VAD insertion. Result: We could monitor all hemodynamic parameters including pcwp PAP cardiac index EKG, adn hour urine as true clinical settings. We observed that the reliability of the VAD was excellent and the hemodynamic property of the experimental animal and end organ perfusion were adequate within 24 hours of experiment. In four lambs surviving 24 hours after insertion the reliability of the VAD and end organ perfusion were excellent and no thrombotic-hemolytic tendency was noted. However after 15 days of experiment the diaphragm of the VAD was torn and it was recommende that the durability of the VAD should be extended. Conclusion : e conclude that the pneumatic VAD developed at Dankook University Biomedical Engineering has good hemodynamic property and low thromboembolic tendency and presents adequate end organ perfusion but we noted that the durability of the device should be expanded further. It will be possible to do more reliable experiment in the future according to the animal experimental method developed in this study especially with the heart failure models.

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Open Heart Surgery of Congenital Heart Diseases -Report of Four Cases- (선천성심질환(先天性心疾患)의 심폐기(心肺器) 개심수술(開心手術) - 4례(例) 보고(報告) -)

  • Kim, Kun Ho;Park, Young Kwan;Jee, Heng Ok;Kim, Young Tae;Rhee, Chong Bae;Chung, Yun Chae;Oh, Chull Soo
    • Journal of Chest Surgery
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    • v.9 no.1
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    • pp.1-9
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    • 1976
  • The present. study reports four cases of congenital heart diseases, who received open heart surgery by the Sarn's Heart-Lung-Machine in the department of Thoracic Surgery, Hanyang University Hospital during the period between July 1975 and May 1976. The Heart-Lung-Machine consisted of the Sarn's five head roller pump motor system (model 5000), heat exchanger, bubble trap, the Rygg-Kyvsgaard oxygenator, and monitors. The priming of pump oxygenator was carried out by the hemodilution method using Hartman's solution and whole blood. Of the four cases of the heart diseases, three whose body weight were below 30kg, received the partial hemodilution priming and the remaining one whose body weight was 52kg received the total hemodilution priming with Hartman's solution alone. The rate of hemodilution was in the average of 60.5ml/kg. Extracorporeal circulation was performed at the perfusion flow rate of the average 94.0ml/kg/min, and at the moderate hypothermia between 35'5"C and 30'5"C of the rectal temperature. In the total cardiopulmonary bypass, arterial blood pressure was anged between 30 mmHg and 85 mmHg, generally maintaining over 60 mmHg and venous pressure was measured between 4 and $23cmH_2O$, generally maintaining below $10cmH_2O$. The first case: The patient, a nine year old girl having the symptoms and physical signs typical to cardiac anomaly was definitely diagnosed as isolated pulmonary stenosis through the cardiac catheterization. There was, however, no cyanosis, no pathological finding by X-ray and E.C.G. tracings. The valvulotomy was performed through the arteriotomy of pulmouary artery under the total cardiopulmonary bypass. Postoperative course of the patient was uneventful, and murmur and the clinical symptoms disappeared. The second case: A 12 year old boy with congenital heart anomaly was positively identified as having ventricular septal defect through the cardiac catheterization. As in the case with the first case, the patient exhibited the symptoms and physical signs typical to cardiac anomaly, but no pathological abnormality by X-ray and E.C.G. tracings. The septal defect was localized on atrioventricular canal and was 2 by 10 mm in size. The septal defect was closed by direct simple sutures under the cardiopulmonary bypass. Postoperative hemodynamic study revealed that the pressure of the right ventricle and pulmonary artery were decreased satisfactory. Postoperative course of the patient was uneventful, and murmur and the clinical symptoms disappeared. The third case: The patient, a 19 year old girl had been experienced the clinical symptoms typical to cardiac anomaly for 16 years. The pink tetralogy of Fallot was definitey diagnosed through the cardiac catheterization. The patient was placed on an ablolute bed rest prior to the operation because of severe exertional dyspnea, fatigability, and frequent syncopal attacks. However, she exhibited very slight cyanosis. Positive findings were noted on E.C.G. tracings and blood picture, but no evidence of pathological abnormality on X-ray was observed. All of the four surgical approaches such as Teflon patch closure (3 by 4cm in size) of ventricular septal defect, myocardial resection of right ventricular outflow tract, valvulotomy of pulmonary valvular stenosis, and pericardial patch closing of ventriculotomy wound were performed in 95 minutes under the cardiopulmonary bypass. Postoperative hemodynamic study revealed that the pressure of the right ventricle was decreased and pulmonary artery was increased satisfactorily. Postoperative course of the patient was uneventful, and murmur and the clinical symptoms disappeared. The fourth case: The patient, a 7 1/4 year old girl had the symptoms of cardiac anomaly for only three years prior to the operation. She was positively identified as having acyanotic tetralogy of Fallot by open heart surgery. The patient showed positive findings by X-ray and E.C.G. tracings, but exhibited no cyanosis and normal blood picture. All of the three surgical approaches, such a myocardial resection of hypertrophic sight ventricular outflow tract, direct suture closing of ventricular septal defect and pericardial patch closing of ventriculotomy wound were carried out in 110 minutes under the cardiopulmonary bypass. Postoperative hemodynamic study revealed that the pressure of the right ventricle was decreased and pulmonary artery was increased satisfactorily. Postoperative course of the patient was uneventful, and the symptoms disappeared.

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Morphologic Changes of the Pulmonary Arteries after Stent Implantation on Branch Pulmonary Artery Stenosis - Impact of Pulmonary Insufficiency - (폐동맥 분지협착에 스텐트 삽입 후 유발되는 폐동맥의 형태변화 - 폐동맥 폐쇄 부전의 역할 -)

  • Kim, Me Jin;Kang, Du Cheol;Choi, Jae Young;Lee, Jong Kyun;Sul, Jun Hee;Lee, Sung Kyu
    • Clinical and Experimental Pediatrics
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    • v.46 no.1
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    • pp.67-75
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    • 2003
  • Purpose : Intravascular stent implantation for the treatment of postoperative branch pulmonary artery(PA) stenosis has been used successfully. However, the cross sectional area of contralateral branch PA does not regress in spite of the successful dilation of the stenotic branch PA after stent implantation. We analyzed the morphologic and hemodynamic factors on the size of branch PA after successful stent implantation. Methods : The subjects in our study were 23 children who had undergone stent implantaion from Jan. 1995 to Jul. 2002 in the Division of Yonsei Pediatric Cardiology. We evaluated the cross sectional area index(CSAI) of branch PA before and after stent implantation at follow-up catheterization. We also investigated factors such as residual pulmonary stenosis, pulmonary regurgitation(PR), systolic pressure of right ventricle, and lung perfusion scan. Results : The CSAI of the RPA without stenosis changed from mean $238{\pm}17mm^2/BSA$ to mean $249{\pm}20mm^2/BSA$(P=0.47), but didn't regress. The CSAI of the LPA with stenosis was increased effectively by stent implantation from the mean $102{\pm}12mm^2/BSA$ to mean $125{\pm}11mm^2/BSA$(P< 0.05). At follow up after stent implantation, the CSAI of PA is correlated with the residual PR fraction after stent implantation. Conclusion : In a group with increased residual PR, CSAI of RPA was found to be significantly increased between the pre- and post-stages of stent implantation. So, we suspect that the pulmonary regurgitation remaining after right ventricle outlet tract(RVOT) dilatation surgery is correlated with the increase in CSAI of RPA.

The Clinical Outcome of Pulmonary Thromboendarterectomy for the Treatment of Chronic Pulmonary Thromboembolism (만성 폐동맥 색전증 환자에서의 폐동맥 내막절제술의 임상적 결과)

  • Bang, Jeong-Hee;Woo, Jong-Soo;Choi, Pil-Jo;Jo, Gwang-Jo;Park, Kwon-Jae;Kim, Si-Ho;Yie, Kil-Soo
    • Journal of Chest Surgery
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    • v.43 no.3
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    • pp.254-259
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    • 2010
  • Background: Diagnosing chronic pulmonary embolism at an early stage is difficult because of the patient’s nonspecific symptoms. This condition is not prevalent in Korea, and in fact, there have been only a few case reports on this in the Korean medical literature. We analyzed the surgical outcome of performing pulmonary thromboendarterectomy in patients with chronic pulmonary embolism. Material and Method: The study subjects included those patients who underwent surgery for chronic pulmonary embolism from 1996 to 2008. For making the diagnosis, echocardiography, chest CT and a pulmonary perfusion scan were performed on the patients who complained of chronic dyspnea. Result: Pulmonary endarterectomy was performed as follows: by incision via a mid-sternal approach (7 patients); by incision via a left posterolateral approach (1 patient); using the deep hypothermic circulatory arrest technique (4 patients); under ventricular fibrillation (3 patients); and under cardioplegic arrest (1 patient). The postoperative systolic pulmonary artery blood pressure significantly decreased from a preoperative value of $78.9{\pm}14.5\;mmHg$ to $45.6{\pm}17.6\;mmHg$ postoperatively (p=0.000). The degree of tricuspid regurgitation was less than grade II after surgery. Two patients died early on, including one patient who had persistent pulmonary hypertension without improvement and right heart failure. Conclusion: Patients who have chronic pulmonary embolism are known to have a poor prognosis. However, we think that early surgical treatment along with making the proper diagnosis before the aggravation of right heart failure can help improve the quality of a patient's life.

The Comparative Study of on Pump CABG during Pulsatile $(T-PLS^{TM})$ and Nonpulsatile $(Bio-pump^{TM})$ Perfusion (관상동맥우회술 시 사용된 박동성펌프$(T-PLS^{TM})$와 비박동성펌프$(Bio-pump^{TM})$의 비교연구)

  • Park Young-Woo;Her Keun;Lim Jae-Ung;Shin Hwa-Kyun;Won Yong-Soon
    • Journal of Chest Surgery
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    • v.39 no.5 s.262
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    • pp.354-358
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    • 2006
  • Background: Pulsatile pumps for extracorporeal circulation have been known to be better for tissue perfusion than non-pulsatile pumps but be detrimental to blood corpuscles. This study is intended to examine the risks and benefits of $T-PLS^{TM}$ through the comparison of clinical effects of $T-PLS^{TM}$ (pulsatile pump) and $Bio-pump^{TM}$ (non-pulsatile pump) used for coronary bypass surgery. Material and Method: The comparison was made on 40 patients who had coronary bypass using $T-PLS^{TM}\;and\;Bio-pump^{TM}$ (20 patients for each) from April 2003 to June 2005. All of the surgeries were operated on pump beating coronary artery bypass graft using cardiopulmonary extra-corporeal circulation. Risk factors before surgery and the condition during surgery and the results were compared. Result: There was no significant difference in age, gender ratio, and risk factors before surgery such as history of diabetes, hypertension, smoking, obstructive pulmonary disease, coronary infarction, and renal failure between the two groups. Surgery duration, hours of heart-lung machine operation, used shunt and grafted coronary branch were little different between the two groups. The two groups had a similar level of systolic arterial pressure, diastolic arterial pressure and mean arterial pressure, but pulse pressure was measured higher in the group with $T-PLS^{TM}\;(46{\pm}15\;mmHg\;in\;T-PLS^{TM}\;vs\;35{\pm}13\;mmHg\;in\;Bio-pump^{TM},\;p<0.05)$. The $T-PLS^{TM}$-operated patients tended to produce more urine volume during surgery, but the difference was not statistically significant $(9.7{\pm}3.9\;cc/min\;in\;T-PLS^{TM}\;vs\;8.9{\pm}3.6\;cc/min\;in\;Bio-pump^{TM},\;p=0.20)$. There was no significant difference in mean duration of respirator usage and 24-hour blood loss after surgery between the two groups. Plasma free Hb was measured lower in the group with $T-PLS^{TM}\;(24.5{\pm}21.7\;mg/dL\;in\;T-PLS^{TM}\;versus\;46.8{\pm}23.0mg/dL\;in\;Bio-pump^{TM},\;p<0.05)$. There was no significant difference in coronary infarction, arrhythmia, renal failure and morbidity rate of cerebrovascular disease. There was a case of death after surgery (death rate of 5%) in the group tested with $T-PLS^{TM}$, but the death rate was not statistically significant. Conclusion: Coronary bypass was operated with $T-PLS^{TM}$ (Pulsatile flow pump) using a heart-lung machine. There was no unexpected event caused by mechanical error during surgery, and the clinical process of the surgery was the same as the surgery for which $Bio-pump^{TM}$ was used. In addition, $T-PLS^{TM}$ used surgery was found to be less detrimental to blood corpuscles than the pulsatile flow has been known to be. Authors of this study could confirm the safety of $T-PLS^{TM}$.

THE CURRENT STATUS OF BIOMEDICAL ENGINEERING IN THE USA

  • Webster, John G.
    • Proceedings of the KOSOMBE Conference
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    • v.1992 no.05
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    • pp.27-47
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    • 1992
  • Engineers have developed new instruments that aid in diagnosis and therapy Ultrasonic imaging has provided a nondamaging method of imaging internal organs. A complex transducer emits ultrasonic waves at many angles and reconstructs a map of internal anatomy and also velocities of blood in vessels. Fast computed tomography permits reconstruction of the 3-dimensional anatomy and perfusion of the heart at 20-Hz rates. Positron emission tomography uses certain isotopes that produce positrons that react with electrons to simultaneously emit two gamma rays in opposite directions. It locates the region of origin by using a ring of discrete scintillation detectors, each in electronic coincidence with an opposing detector. In magnetic resonance imaging, the patient is placed in a very strong magnetic field. The precessing of the hydrogen atoms is perturbed by an interrogating field to yield two-dimensional images of soft tissue having exceptional clarity. As an alternative to radiology image processing, film archiving, and retrieval, picture archiving and communication systems (PACS) are being implemented. Images from computed radiography, magnetic resonance imaging (MRI), nuclear medicine, and ultrasound are digitized, transmitted, and stored in computers for retrieval at distributed work stations. In electrical impedance tomography, electrodes are placed around the thorax. 50-kHz current is injected between two electrodes and voltages are measured on all other electrodes. A computer processes the data to yield an image of the resistivity of a 2-dimensional slice of the thorax. During fetal monitoring, a corkscrew electrode is screwed into the fetal scalp to measure the fetal electrocardiogram. Correlations with uterine contractions yield information on the status of the fetus during delivery To measure cardiac output by thermodilution, cold saline is injected into the right atrium. A thermistor in the right pulmonary artery yields temperature measurements, from which we can calculate cardiac output. In impedance cardiography, we measure the changes in electrical impedance as the heart ejects blood into the arteries. Motion artifacts are large, so signal averaging is useful during monitoring. An intraarterial blood gas monitoring system permits monitoring in real time. Light is sent down optical fibers inserted into the radial artery, where it is absorbed by dyes, which reemit the light at a different wavelength. The emitted light travels up optical fibers where an external instrument determines O2, CO2, and pH. Therapeutic devices include the electrosurgical unit. A high-frequency electric arc is drawn between the knife and the tissue. The arc cuts and the heat coagulates, thus preventing blood loss. Hyperthermia has demonstrated antitumor effects in patients in whom all conventional modes of therapy have failed. Methods of raising tumor temperature include focused ultrasound, radio-frequency power through needles, or microwaves. When the heart stops pumping, we use the defibrillator to restore normal pumping. A brief, high-current pulse through the heart synchronizes all cardiac fibers to restore normal rhythm. When the cardiac rhythm is too slow, we implant the cardiac pacemaker. An electrode within the heart stimulates the cardiac muscle to contract at the normal rate. When the cardiac valves are narrowed or leak, we implant an artificial valve. Silicone rubber and Teflon are used for biocompatibility. Artificial hearts powered by pneumatic hoses have been implanted in humans. However, the quality of life gradually degrades, and death ensues. When kidney stones develop, lithotripsy is used. A spark creates a pressure wave, which is focused on the stone and fragments it. The pieces pass out normally. When kidneys fail, the blood is cleansed during hemodialysis. Urea passes through a porous membrane to a dialysate bath to lower its concentration in the blood. The blind are able to read by scanning the Optacon with their fingertips. A camera scans letters and converts them to an array of vibrating pins. The deaf are able to hear using a cochlear implant. A microphone detects sound and divides it into frequency bands. 22 electrodes within the cochlea stimulate the acoustic the acoustic nerve to provide sound patterns. For those who have lost muscle function in the limbs, researchers are implanting electrodes to stimulate the muscle. Sensors in the legs and arms feed back signals to a computer that coordinates the stimulators to provide limb motion. For those with high spinal cord injury, a puff and sip switch can control a computer and permit the disabled person operate the computer and communicate with the outside world.

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