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2.
Thorac Cardiovasc Surg ; 52(4): 230-1, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15293160

RESUMO

Coronary artery aneurysms are a rare condition with left-main trunk aneurysms occurring in only about 0.1 % of the population. We report on a giant left-main coronary artery aneurysm in a young male status post two previous open-heart operations. The aneurysm was successfully treated by patch occlusion of the ostial orifice and coronary revascularization of the left anterior descending and circumflex arteries.


Assuntos
Procedimentos Cirúrgicos Cardiovasculares/métodos , Aneurisma Coronário/cirurgia , Adulto , Fístula Artério-Arterial/complicações , Aneurisma Coronário/complicações , Aneurisma Coronário/diagnóstico , Angiografia Coronária , Anomalias dos Vasos Coronários , Ventrículos do Coração/anormalidades , Humanos , Imageamento por Ressonância Magnética , Masculino , Recidiva , Reoperação , Resultado do Tratamento
3.
Eur J Cardiothorac Surg ; 20(4): 842-6, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11574235

RESUMO

OBJECTIVE: The natural history of medically treated multivalvular endocarditis is associated with dismal short and long term survival. However, the impact of surgical intervention on these results is relatively unknown. The objective of this retrospective study was to report our long-term results in patients requiring multivalve surgery for multivalvular endocarditis. METHODS AND RESULTS: Over a 24 year period beginning in 1972, multivalve surgical procedures were performed on 63 patients for infective endocarditis. Prosthetic valve endocarditis was present in 25 (40%), and acute or active endocarditis in 38 (60%). The early mortality was 16%. Out of 53 patients discharged from the hospital 87+/-4% were alive at 5 years and 64+/-9% at 10 years. There was no difference in early or late mortality between patients with prosthetic and native endocarditis (P=0.15 and P=0.77 for early and late mortality, respectively). The presence of active endocarditis did not affect operative outcome or late mortality. Twenty-one patients (88%) were in NYHA FC I, and none were in NYHA FC IV. The only prognostic factor of early and late mortality was the presence of an abscess at the time of the surgery. CONCLUSIONS: These results indicate that multivalve infective endocarditis treated surgically is associated with acceptable early and late mortality and excellent postoperative functional status. The early surgical intervention prior to an abscess formation offers the best chance for survival of patients with multivalve endocarditis.


Assuntos
Bioprótese , Endocardite Bacteriana/cirurgia , Doenças das Valvas Cardíacas/cirurgia , Próteses Valvulares Cardíacas , Adolescente , Adulto , Idoso , Endocardite Bacteriana/mortalidade , Feminino , Seguimentos , Doenças das Valvas Cardíacas/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/mortalidade , Complicações Pós-Operatórias/cirurgia , Desenho de Prótese , Reoperação , Estudos Retrospectivos , Taxa de Sobrevida
4.
Eur J Cardiothorac Surg ; 20(2): 252-6, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11463540

RESUMO

OBJECTIVE: The composite mechanical valve conduit has been most commonly used for patients who require combined aortic valve, root, and ascending aorta replacement, but is limited, especially in the elderly, because of the need for long-term anticoagulation. We report the first consecutive series of patients in whom a composite stentless valve with graft extension, which does not require long-term anticoagulation, was performed. METHODS: Between April 1998 and July 2000, eight patients with severe aortic root and ascending aortic pathology underwent a combined aortic valve, root, and ascending aorta replacement with a Freestyle stentless porcine valve with a Hemashield graft extension. Mean age was 74 (range 56--82), three were males. Concomitant procedures included coronary artery bypass graft (CABG) alone (n=2), mitral valve replacement with atrial septal defect repair (n=1) and CABG with septal myomectomy (n=1). RESULTS: Operative mortality was zero. Median aortic cross-clamp and cardiopulmonary bypass times were 150 and 203 min, respectively. Two patients returned to the operating room for bleeding. Median blood transfusions and hospital length of stay were 4 units and 11 days, respectively. CONCLUSIONS: The composite stentless valve with graft extension is a reasonable alternative to a mechanical valve conduit for patients who require a combined aortic valve, root, and ascending aorta replacement, in whom anticoagulation is not desirable or contraindicated.


Assuntos
Aneurisma da Aorta Torácica/cirurgia , Insuficiência da Valva Aórtica/cirurgia , Bioprótese , Implante de Prótese Vascular , Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Idoso , Idoso de 80 Anos ou mais , Anastomose Cirúrgica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese
5.
Ann Vasc Surg ; 15(6): 713-5, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11769158

RESUMO

Morbidity of infrainguinal bypass surgery is mostly related to cardiac complication, graft thrombosis, and wound infections. Neurologic complications in these patients are unusual and generally related to traumatic peripheral nerve injury or ischemia. Anterior spinal cord ischemia, manifest clinically as flaccid paraplegia or lower extremity paraparesis, is a complication usually associated with aortic surgery. Reported here is a case of an 81-year-old male who developed spinal cord ischemia after infrainguinal bypass under epidural anesthesia.


Assuntos
Canal Inguinal/cirurgia , Complicações Pós-Operatórias/etiologia , Isquemia do Cordão Espinal/etiologia , Procedimentos Cirúrgicos Vasculares , Idoso , Idoso de 80 Anos ou mais , Aneurisma da Aorta Abdominal/complicações , Aneurisma da Aorta Abdominal/cirurgia , Veia Femoral/transplante , Humanos , Imageamento por Ressonância Magnética , Masculino , Veia Safena/transplante , Tomografia Computadorizada por Raios X , Procedimentos Cirúrgicos Vasculares/efeitos adversos
6.
Ann Thorac Surg ; 67(5): 1497-9, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10355448

RESUMO

The outcome of patients with thoracic or thoracoabdominal aortic aneurysm is often determined by the concomitant coronary artery disease. Two patients with thoracic and thoracoabdominal aortic aneurysm and concomitant single-vessel coronary artery disease underwent combined myocardial revascularization and repair of aortic aneurysm. The operations were performed through a left thoracotomy and thoracoabdominal incision with distal aortic perfusion using a partial femoro-femoral bypass and selective right lung ventilation. Coronary anastomoses were performed on the beating heart, and the aneurysm was replaced with a woven Dacron tube graft.


Assuntos
Aneurisma da Aorta Torácica/complicações , Aneurisma da Aorta Torácica/cirurgia , Ponte de Artéria Coronária , Doença das Coronárias/complicações , Doença das Coronárias/cirurgia , Idoso , Implante de Prótese Vascular , Feminino , Humanos , Masculino
7.
Eur J Cardiothorac Surg ; 11(1): 157-61, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9030805

RESUMO

OBJECTIVE: There is a growing body of evidence that perfusion temperature during cardiopulmonary bypass (CPB) influences postoperative systemic vascular resistance (SVR). The reason for this is not clear. Extracorporeal circulation can provoke raised plasma levels of endothelin-1 (ET-1), a very potent vasoconstrictor peptide produced by endothelial cells. We therefore analysed the effect of CPB temperature on postoperative vascular resistance and plasma concentrations of ET-1. METHODS: Thirty four patients undergoing elective coronary artery bypass grafting procedures were randomly assigned for either normothermic (37 degrees C, n = 17) or hypothermic CPB (28 degrees C, n = 17). Serial measurements of SVR and plasma ET-1 concentrations were performed before, during, and until 9 h after CPB measured. RESULTS: As a consequence of CPB, plasma ET-1 levels increased slightly in both groups. In normothermic patients, ET-1 reached maximal levels at the end of CPB whereas ET-1 levels in patients after hypothermic CPB had a tendency to further increase during the stay in the intensive care unit. Plasma ET-1 levels were significantly higher in patients 9 h postoperatively after hypothermic CPB (1.94 +/- 0.28 vs. 1.30 +/- 0.12 pg/ml, P = 0.033), which was associated with significantly higher systemic vascular resistance index (SVRI) in these patients (area under the curve; 1978 +/- 76 vs. 1626 +/- 69 dyne s/cm5 per m2, P = 0.003). Plasma ET-1 levels showed a positive correlation with postoperative SVRI (P = 0.008, r = 0.51) and a negative correlation with minimal rectal temperature during CPB (P = 0.006, r = 0.55). CONCLUSIONS: These results suggests that the hemodynamic differences after normothermic and hypothermic CPB might be mediated, at least in part, by temperature dependent changes in ET-1 plasma levels.


Assuntos
Ponte Cardiopulmonar , Doença das Coronárias/cirurgia , Endotelina-1/fisiologia , Hemodinâmica/fisiologia , Hipotermia Induzida , Complicações Pós-Operatórias/fisiopatologia , Adulto , Idoso , Doença das Coronárias/fisiopatologia , Cuidados Críticos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Resistência Vascular/fisiologia
8.
Ann Thorac Surg ; 62(4): 1146-51, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8823104

RESUMO

BACKGROUND: There is some evidence that continuous warm blood cardioplegia offers good myocardial protection; however, the effects of interrupting cardioplegia remain controversial. To study this, we compared the effects of continuous and intermittent antegrade warm (37 degrees C) blood cardioplegia on functional recovery after prolonged cardiac arrest (180 minutes). METHODS: Twenty-four juvenile pigs were randomly assigned into four groups. Group 1 received continuous cardioplegia, group 2 underwent several periods of 15 minutes of cardioplegia interrupted by 5 minutes of normothermic ischemia, and group 3 underwent several periods of 10 minutes of cardioplegia interrupted by episodes of 10 minutes. The hearts of group 4 received no cardioplegia. Left ventricular systolic function was assessed from fractional left ventricular shortening and percentage left ventricular wall thickening, and left ventricular diastolic function was determined from the time constant of relaxation and the constant of myocardial stiffness. RESULTS: Systolic and diastolic functions were slightly depressed 1 and 2 hours after cross-clamp removal in all four groups, without significant differences among the groups. CONCLUSIONS: These data suggest that antegrade warm blood cardioplegia can be interrupted for up to 10 minutes without obvious negative effects on left ventricular function in the normal myocardium, provided that the intermittent doses of cardioplegia are sufficient to restore the metabolic demands of the arrested myocardium.


Assuntos
Parada Cardíaca Induzida/métodos , Função Ventricular Esquerda , Animais , Sangue , Pressão Sanguínea , Circulação Coronária , Suínos , Temperatura , Fatores de Tempo
9.
J Pediatr Surg ; 31(9): 1265-7, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8887098

RESUMO

Phrenic nerve injury with resulting diaphragm paralysis occurred in 25 (1.5%) of 1,656 cardiac surgical procedures in children during a 10-year period. Phrenic nerve injury was most commonly noted in patients who had undergone previous cardiac surgery (16 of 165, 10%; P < .0001), typically after a previous Blalock-Taussig shunt (10 of 53, 19%; P = .007). Plication of the diaphragm (7 thoracic, 4 abdominal) was performed in 11 patients (44%). Indications for plication were inability to wean from mechanical ventilation (5 patients) and persistent or recurrent respiratory distress (6 patients). The patients who needed diaphragm plication were significantly younger than those who were managed conservatively (median, 11 months [4 days to 23 months] versus 20 months [4 months to 16 years]; P = .01). All patients older than 2 years were extubated within 3 days (mean, 1.5 days) and did not need any surgical intervention. The median follow-up period was 3.2 years, and no patient has had recurrent respiratory problems. There were no deaths as a direct result of phrenic nerve injury. Phrenic nerve injury after cardiac surgery is a serious complication that often leads to respiratory insufficiency in patients under than 2 years of age. For such patients, early diaphragm plication is a simple and effective procedure that prevents the complications of prolonged mechanical ventilation.


Assuntos
Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Nervo Frênico/lesões , Paralisia Respiratória/etiologia , Adolescente , Criança , Pré-Escolar , Diafragma/cirurgia , Cardiopatias Congênitas/cirurgia , Humanos , Lactente , Recém-Nascido
10.
ASAIO J ; 42(4): 246-9, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8828778

RESUMO

An extra corporeal venovenous bypass circuit (right atrium to pulmonary artery), including an intravascular gas exchanger in a blood chamber with a variable inner diameter, was developed for ex vivo evaluation of the host vessel diameter/intravascular oxygen transfer relationship. Three host vessel diameters mimicking different configurations of the caval axis were studied in three bovine experiments (body weight 82 +/- 3 kg). Blood flow was 3,000 ml/min and device oxygen inflow was 2,300 ml/min. Serial blood samples were taken for 26 mm, 23 mm, and 20 mm inner blood chamber diameters after hemodynamic stabilization before and after exposure of the circulating blood to the intravascular gas exchanger (sampling ports at blood chamber inlet and outlet). Measured oxygen saturation at the blood chamber inlet was 25.0 +/- 11.7% for the 26 mm diameter as compared to 31.7 +/- 12.6% for 23 mm, and 28.7 +/- 9.2% for 20 mm. At the outlet, the corresponding O2 saturations were 34.5 +/- 11.5% for 26 mm, 42.9 +/- 8.8% for 23 mm, and 43.2 +/- 6.2 for 20 mm. Total O2 transfer was 24.9 +/- 11.5 ml/min for 26 mm, 31.9 +/- 7.4 ml/min for 23 mm, and 35.9 +/- 12.2 ml/min for 20 mm (p < 0.05). Likewise, O2 transfer rate was 8.3 +/- 3.8 ml/L, 10.6 +/- 2.4 ml/L, and 12.0 +/- 4.0 ml/L (p < 0.05). Parallel analyses of total CO2 transfer and CO2 transfer rates provided less consistent findings. At 3 L/min, the pressure drop between the inlet and outlet of the blood chamber was 12 +/- 3 mmHg for 26 mm, 26 +/- 1 mmHg for 23 mm, and 38 +/- 2 mmHg for 20 mm diameters (p < 0.001). The authors conclude that oxygen transfer of a given intravascular gas exchanger appears to be indirectly proportional to the host vessel diameter. Increasing blood pressure gradient as a function of decreasing diameter has to be considered in clinical application.


Assuntos
Consumo de Oxigênio/fisiologia , Oxigenadores , Animais , Velocidade do Fluxo Sanguíneo/fisiologia , Pressão Sanguínea/efeitos dos fármacos , Vasos Sanguíneos/fisiologia , Dióxido de Carbono/metabolismo , Bovinos , Pressão Parcial
11.
Ann Thorac Surg ; 60(6): 1665-70, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8787460

RESUMO

BACKGROUND: The intravascular gas exchanger is a lung assist device for augmentation of gas exchange in critically ill patients with severe acute respiratory failure. These patients often require inotropic support therapy due to the cardiovascular instability that almost inevitably accompanies severe respiratory failure. METHODS: We investigated the interaction of vasoactive medication (dopamine, nitroglycerin, and noradrenaline) with the gas exchange performances of the intravascular gas exchanger in a bovine experimental model. RESULTS: Dopamine administration highly increased cardiac output, caval flow rates, and diameter of vena cava inferior. These effects resulted in a significant increase in oxygen transfer (baseline, 35 +/- 6 mL/min versus 153 +/- 27 mL/min at 20 micrograms.kg-1.min-1 of dopamine, p < 0.001) and carbon dioxide elimination (baseline, 35 +/- 2 mL/min versus 47 +/- 4 mL/min at 20 micrograms.kg-1.min-1 of dopamine, p < 0.001). Administration of nitroglycerin did not cause significant changes of the hemodynamic parameters nor did it affect the oxygen transfer or carbon dioxide elimination. Noradrenaline caused a moderate increase in cardiac output and caval flow, but no changes of caval diameter. hemodynamic changes were accompanied by an increase in oxygen transfer from 38 +/- 5 mL/min to 68 +/- 7 mL/min (p < 0.01) and carbon dioxide elimination from 33 +/- 1 mL/min to 40 +/- 1 mL/min (p = 0.03). The multiple regression analysis showed significant influence of changes in cardiac output on oxygen transfer (p < 0.001) and carbon dioxide elimination (p = 0.004). The administration of vasoactive drugs induced slight changes in caval diameter that did not significantly affect the gas transfer. CONCLUSIONS: The results from our study reveal the major influence of cardiac output on efficiency of gas transfer of the intravascular oxygenator.


Assuntos
Hemodinâmica , Oxigenadores , Troca Gasosa Pulmonar , Animais , Velocidade do Fluxo Sanguíneo , Débito Cardíaco/efeitos dos fármacos , Bovinos , Dopamina/farmacologia , Hemodinâmica/efeitos dos fármacos , Nitroglicerina/farmacologia , Norepinefrina/farmacologia , Troca Gasosa Pulmonar/efeitos dos fármacos , Vasoconstritores/farmacologia , Vasodilatadores/farmacologia , Veia Cava Inferior/efeitos dos fármacos , Veia Cava Inferior/fisiologia
12.
Chest ; 108(6): 1551-6, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7497759

RESUMO

To test the hypothesis that acute lung injury during cardiopulmonary bypass (CPB) is related to the activation of neutrophils and the body temperature during bypass, we determined the differential WBC count, plasma elastase concentrations, and lung function before, during, and after CPB in 38 patients undergoing elective coronary artery bypass surgery. The patients were randomly assigned to receive either normothermic (n = 19, rectal temperature: 35.9 +/- 0.1 degrees C, mean +/- SE) or hypothermic (n = 19, 29.2 +/- 0.5 degrees C) CPB. The cellular response to the extracorporeal circulation was significantly delayed in the hypothermic group with a later onset of neutrophilia and a later increase in plasma elastase levels during bypass. Lung function deteriorated significantly after CPB as assessed by respiratory index, alveolar-arterial oxygen gradient, and intrapulmonary shunt, independent of bypass temperature. There was a positive correlation between peak elastase concentrations and postoperative respiratory index as well as intrapulmonary shunt (R2 = 0.5, p = 0.002 and R2 = 0.45, p = 0.003, respectively). Besides peak plasma elastase levels, multiple regression revealed no significant influence of other independent factors on postoperative lung dysfunction in our patients.


Assuntos
Ponte Cardiopulmonar/efeitos adversos , Neutrófilos/fisiologia , Síndrome do Desconforto Respiratório/etiologia , Temperatura Corporal , Feminino , Humanos , Contagem de Leucócitos , Elastase de Leucócito , Masculino , Pessoa de Meia-Idade , Elastase Pancreática/sangue , Síndrome do Desconforto Respiratório/sangue , Síndrome do Desconforto Respiratório/fisiopatologia , Mecânica Respiratória
13.
J Thorac Cardiovasc Surg ; 109(6): 1138-45, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7776678

RESUMO

The accumulation of activated leukocytes in the pulmonary circulation plays an important role in the pathogenesis of lung dysfunction associated with cardiopulmonary bypass. Animal studies have demonstrated that the elimination of leukocytes from the circulation reduces postoperative lung injury and improves postoperative pulmonary function. We conducted a prospective randomized clinical study to evaluate whether postoperative lung function could be improved by use of a leukocyte filter during cardiopulmonary bypass. Elective coronary artery bypass grafting was done with a leukocyte-depleting arterial blood filter incorporated in the extracorporeal circuit (14 patients, leukocyte filter group) or without the filter (18 patients, control group). Blood samples collected at intervals before, during, and after operation were used for analysis of blood cell counts, elastase concentrations, and arterial blood gases. The use of the leukocyte filter caused no significant reduction in leukocyte count (p = 0.86). There were no differences in postoperative lung function between the groups, as assessed through (1) oxygenation index (290 for leukocyte filter group compared with 329 for control group, 95% confidence interval, 286 to 372, p = 0.21), (2) pulmonary vascular resistance (p = 0.10), and (3) intubation time (16.6 hours for leukocyte filter group versus 15.7 hours for control group, 95% confidence interval, 12.1 to 19.1 hours, p = 0.72). The levels of neutrophil elastase were significantly higher at the end of cardiopulmonary bypass in the leukocyte filter group (460 microgram/L in leukocyte filter group versus 230 microgram/L in control group, 95% confidence interval, 101 to 359 microgram/L, p = 0.003). We conclude that the clinical use of the present form of leukocyte-depleting filter did not improve any of the postoperative lung function parameters analyzed in this study.


Assuntos
Ponte Cardiopulmonar/métodos , Ponte de Artéria Coronária/métodos , Leucócitos , Pneumopatias/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Ponte Cardiopulmonar/instrumentação , Separação Celular , Filtração/instrumentação , Humanos , Contagem de Leucócitos , Elastase de Leucócito , Masculino , Pessoa de Meia-Idade , Elastase Pancreática/sangue , Fatores de Tempo , Resistência Vascular/fisiologia
14.
Crit Care Med ; 23(5): 944-9, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7736755

RESUMO

OBJECTIVE: To compare the methods for continuous and bolus thermodilution cardiac output measurements. DESIGN: In vivo and in vitro experimental studies. SETTING: Surgical research division in a university hospital. SUBJECTS: Eight calves and flow bench model. INTERVENTIONS: Data were collected in vivo from eight calves instrumented with pulmonary artery catheters, which allowed both continuous and bolus thermodilution measurements. The pulmonary artery catheter was placed through the external jugular vein. All in vitro measurements were performed using a flow bench model. MEASUREMENTS AND MAIN RESULTS: A total of 232 bolus and continuous thermodilution measurements were analysed in vivo to determine the degree of agreement between the two methods. The absolute measurement bias was 0.14 L/min with 95% confidence limits ranging from -0.83 to 1.15 L/min. In vitro analysis of 576 measurements at six different temperature points (range 31 degrees to 41 degrees C), using clinically relevant flows (2 to 9 L/min), showed overestimation of flow values using continuous and bolus thermodilution methods. However, the continuous method showed better accuracy by a lower degree of overestimation. Systematic error was 9.7 +/- 8.4 (SD) % for continuous and 11.1 +/- 6.3% for the bolus method (p < .001). This effect was especially evident at lower flow rates. The influence of various temperatures on the accuracy and reproducibility of both methods of measurement was statistically significant but not clinically relevant. The infusion of lactated Ringer's lactate solution (infusion rates 100 to 1000 mL/hr) affects both methods at a low flow rate of 2 L/min, without causing a significant effect on continuous measurement at a higher flow rate (4 L/min). Shunting of 50% of circulating volume to the distal part of the thermal filament of the pulmonary catheter impaired the accuracy of continuous measurement without affecting results from bolus measurements (systematic error -26.8 +/- 8.2% for continuous and -5.2 +/- 4.1% for bolus thermodilution). CONCLUSIONS: Continuous thermodilution cardiac output measurement provided higher accuracy and greater resistance to thermal noise than standard bolus measurements. The correct placement of the catheter is essential for precise measurements.


Assuntos
Débito Cardíaco , Termodiluição/métodos , Análise de Variância , Animais , Cateterismo Periférico/instrumentação , Cateterismo Periférico/métodos , Bovinos , Estudos de Avaliação como Assunto , Modelos Cardiovasculares , Modelos Estruturais , Análise de Regressão , Reprodutibilidade dos Testes , Estatísticas não Paramétricas , Temperatura , Termodiluição/instrumentação , Termodiluição/estatística & dados numéricos
15.
Ann Thorac Surg ; 59(1): 137-43, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7818312

RESUMO

To evaluate the influence of perfusion temperature on systemic effects of cardiopulmonary bypass (CPB), 30 patients undergoing elective coronary artery bypass grafting were randomly assigned to either normothermic (warm, n = 14, 36 degrees C) or hypothermic (cold, n = 16, 28 degrees C) CPB. Serial hemodynamic measurements and blood samples were obtained before, during and after the CPB procedure. During CPB, there were no differences between both groups in the need for vasopressors (norepinephrine, phenylephrine), urinary output, or fluid balance. In the early postoperative period, normothermic CPB patients had significantly lower systemic vascular resistance and higher cardiac index measurements (mean +/- standard error: systemic vascular resistance, 880 +/- 27 versus 1,060 +/- 57 dyne.s.cm-5, p = 0.025; cardiac index, 3.6 +/- 0.1 versus 2.9 +/- 0.1 L.min-1.m-2, p = 0.01) without differences in the administration of vasoactive drugs. Blood loss was significantly higher in patients after hypothermic CPB (median [range] body surface area: 370 [180-560] versus 490 [280-2,120] mL/m2, p = 0.0006), with a greater need for transfusion of erythrocytes and fresh frozen plasma. Plasma levels of tumor necrosis factor and soluble tumor necrosis factor receptors increased during and after CPB, independent of perfusion temperature. This study suggests a significant influence of CPB temperature and respective perfusion management on postoperative hemodynamics and blood loss. Normothermic CPB is not associated with additional systemic adverse effects.


Assuntos
Ponte Cardiopulmonar/métodos , Perda Sanguínea Cirúrgica , Transfusão de Sangue , Ponte de Artéria Coronária , Feminino , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Receptores do Fator de Necrose Tumoral/análise , Temperatura , Fator de Necrose Tumoral alfa/análise
16.
Int J Artif Organs ; 17(12): 651-6, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7759145

RESUMO

The present study was designed for ex vivo evaluation of a heparin coated hard shell venous reservoir in comparison to uncoated control reservoirs. An open chest bovine right heart bypass model (n = 9, bodyweight 72 +/- 6 kg) with passive blood drainage from the right atrium into the venous reservoir and active retransfusion into the pulmonary artery (roller pump) was selected for this purpose. Clear priming was used for the open perfusion circuit. No heparin was given before or during the evaluation period which was scheduled for 6 hours. Reservoir blood flow was at the beginning 3.5 +/- 0.6 l/min for coated versus 3.4 +/- 0.3 l/min for uncoated (NS). After 6 hours, blood flow was 3.3 +/- 0.1 l/min for coated versus 2.7 +/- 0.4 l/min for uncoated (p < 0.05). Hematocrit moved from a baseline level of 30 +/- 2% for coated versus 28 +/- 3% for uncoated (NS) to 28 +/- 3% for coated versus 27 +/- 5% for uncoated (NS) after 6 hours. Prebypass platelet levels of 100% in both groups moved to 84 +/- 3% for coated versus 78 +/- 23% for uncoated (NS) after 6 hours. Activated coagulation time (ACT) before bypass was 148 +/- 12 s for coated and 153 +/- 6 s for uncoated (NS). After 6 hours, ACT was 160 +/- 9 s for coated versus 152 +/- 5 s for uncoated (NS). Thrombin time before bypass was 15 +/- 2 s for coated versus 16 +/- 2 s for uncoated (NS).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Circulação Coronária/fisiologia , Derivação Cardíaca Direita/instrumentação , Heparina/normas , Artéria Pulmonar/ultraestrutura , Animais , Antitrombina III/metabolismo , Coagulação Sanguínea/fisiologia , Plaquetas/citologia , Plaquetas/metabolismo , Proteínas Sanguíneas/metabolismo , Bovinos , Fibrinopeptídeo A/metabolismo , Hematócrito , Heparina/química , Agregação Plaquetária/fisiologia , Artéria Pulmonar/metabolismo , Tempo de Coagulação do Sangue Total
17.
Helv Chir Acta ; 60(6): 1159-62, 1994 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-7875998

RESUMO

The hemopump HP 31 is an improved version of a catheter-mounted, transvalvular, left ventricular assist device, which can be placed into the left ventricle through the ascending aorta. The purpose of this study was to examine the influence of hematocrit and afterload on the pump flow. The hemopump was tested using a flow bench model filled with heparinized bovine blood. The measurements were performed at four various hematocrit values: 16%, 24%, 32%, and 40%. The pump flow was measured at each hematocrit value under increasing afterload pressures (40-120 mm Hg), by all pump speed levels (n = 7). The average pump flow at highest pump speed and lowest afterload was 5.1 +/- 0.3 l/min (mean +/- standard deviation). The influence of afterload on the pump flow was statistically significant (p < 0.001). The highest afterload pressure of 120 mm Hg caused a reduction in pump flow of 24 +/- 5%. The alterations of hematocrit values caused no statistically significant influence on the pump flow (p = 0.72). The results of our study enabled the construction of the nomogram for the in vivo determination of the pump flow. The in vivo performances of the hemopump can be improved through the afterload reduction, especially in the weaning phase of treatment. The oxygen delivery can be improved through the increase in hematocrit values without significant impairment of the pump flow.


Assuntos
Coração Auxiliar , Hemodinâmica/fisiologia , Animais , Velocidade do Fluxo Sanguíneo/fisiologia , Pressão Sanguínea/fisiologia , Bovinos , Desenho de Equipamento , Hematócrito
18.
Ann Thorac Surg ; 58(3): 677-83; discussion 683-4, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7944688

RESUMO

The purpose of the study was to investigate the effect of omental microvascular cell seeding on the patency of small-diameter Dacron prostheses usable for coronary artery bypass grafting. In a canine carotid artery model, each dog (n = 64) received one seeded and one similar nonseeded Dacron prosthesis (internal diameter = 4 or 6 mm). Enzymatically harvested omental microvascular cells (omentum = 27.6 +/- 5.9 g [+/- the standard deviation]; range, 17 to 50 g) were seeded prior to implantation. The seeding density was 1.91 +/- 0.26 [+/- the standard error] x 10(6) cells/cm2 of graft surface. Dipyridamole (75 mg/d) and acetylsalicylic acid (325 mg/d) were administered orally for 4 weeks postoperatively. The prostheses were explanted between 2 and 52 weeks after placement. The results were assessed by angiography; light, scanning electron, and transmission electron microscopy; and morphometry. The seeded grafts developed a uniform luminal monolayer of endothelial cells with minimal platelet or cellular deposition. These grafts also had a significantly higher overall patency rate and significantly larger thrombus-free surface areas than the nonseeded grafts. The overall actuarial patency rates at 1 week, 5, 12, 26, and 52 weeks were 100%, 98%, 93%, 93%, and 93%, respectively, for seeded Dacron grafts and 100%, 91%, 61%, 54%, and 18%, respectively, for nonseeded grafts. The patency rates of Dacron grafts usable for coronary artery bypass grafting are significantly improved by seeding with omental microvascular cells in a canine model.


Assuntos
Prótese Vascular/instrumentação , Artérias Carótidas/cirurgia , Transplante de Células , Ponte de Artéria Coronária/instrumentação , Endotélio Vascular/citologia , Omento , Polietilenotereftalatos , Próteses e Implantes , Grau de Desobstrução Vascular , Análise Atuarial , Animais , Prótese Vascular/métodos , Divisão Celular , Ponte de Artéria Coronária/métodos , Cães , Endotélio Vascular/fisiologia , Sobrevivência de Enxerto , Microscopia Eletrônica de Varredura , Modelos Biológicos , Desenho de Prótese , Propriedades de Superfície , Fatores de Tempo
19.
Thorac Cardiovasc Surg ; 42(1): 32-5, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8184391

RESUMO

The current study was designed to evaluate a method for continuous measurement of cardiac output. The system consists of a modified pulmonary artery catheter that uses the thermodilution principle for determination of cardiac output. The evaluation was performed in vitro and in vivo. In-vitro evaluation was performed using a simple flow bench model (flow 2-9 L/min). Both continuous and bolus thermodilution methods were compared. Both methods showed good correlation with the pump flow calibrated using a volumetric tank and timer (correlation coefficient (r) for bolus thermodilution = 0.92, r for continuous thermodilution = 0.90). In-vivo evaluation was performed in six bovine experiments. Data from a total of 87 pairs of bolus versus continuous measurements were obtained. The cardiac output ranged from 1.9 to 8.9 L/min. The absolute measurement bias was not significant (mean: -0.07 L/min; 95% confidence limits: -0.87 and 0.73 L/min). The squared correlation coefficient from linear regression was 0.92. The results from this study suggest that the new continuous thermodilution measurement system for cardiac output provides accurate data in vitro and in vivo. Continuous monitoring of cardiac output adds a new dimension for evaluation of the patient's hemodynamic profile. Furthermore, significant volume load due to bolus thermodilution measurements can be avoided.


Assuntos
Débito Cardíaco/fisiologia , Termodiluição , Animais , Bovinos , Humanos , Modelos Cardiovasculares
20.
Helv Chir Acta ; 60(3): 387-91, 1993 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-8119819

RESUMO

UNLABELLED: There is some evidence of improved myocardial protection with warm continuous blood cardioplegia. Warm cardioplegia however implies warm (normothermic) cardiopulmonary bypass (CPB). We evaluated retrospectively the influence of bypass temperature on the intra- and postoperative course of 121 patients, operated on for valvular and/or coronary artery disease. Only elective procedures with continuous blood cardioplegia were included. The patients were divided in two groups: warm group (n = 78): normothermic CPB (venous temperature > 33 degrees C) cold group (n = 43): hypothermic CPB (< 33 degrees C). RESULTS: normothermic CPB resulted in a significantly shorter CPB time (84 + 3 min vs. 98 +/- 6 min, p = 0.02, mean +/- 1 standard error of the mean). In addition there was a higher need for vasoconstrictive drugs during cold CPB (Noradrenalin: 19 +/- 3 micrograms vs. 90 +/- 32 micrograms, p = 0.003). There was no difference in enzyme levels on the first postoperative day (amylase, creatinkinase, creatinin), in postoperative complication rate (resuscitations, rethoracotomies, cerebrovascular incidents) and mortality (warm 3% vs. cold 2%) between the two groups. The postoperative time until extubation however was significantly shorter in the warm group (33 +/- 5 h vs. 60 +/- 11 h, p = 0.04). CONCLUSION: there is no evidence of increased morbidity due to normothermic CPB. The shorter time until extubation may be due to a improved postoperative lung function and/or a more stable hemodynamic postoperative course after normothermic CPB.


Assuntos
Ponte Cardiopulmonar , Doença das Coronárias/cirurgia , Doenças das Valvas Cardíacas/cirurgia , Hipotermia Induzida , Complicações Pós-Operatórias/mortalidade , Temperatura Corporal/fisiologia , Doença das Coronárias/mortalidade , Feminino , Doenças das Valvas Cardíacas/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida
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