RESUMO
BACKGROUND: It is essential to control hemodynamics in cardiac surgery. Patients are often monitored extensively in order to optimize hemodynamic performance. However, pre-operative values are normally unknown. Furthermore, hemodynamic goals may seem arbitrary and the lack of an evidence-based consensus may lead to both under- and over-treatment. The aim of this study was to evaluate the variables most commonly used for hemodynamic guidance in the post-operative period. METHODS: Ten patients scheduled for elective cardiac surgery were followed with invasive hemodynamic monitoring the night before surgery. All data were recorded automatically and electronically. RESULTS: We found considerable inter-patient differences and intra-patient variation. The greatest intra-patient variation was found in the cardiac index (CI), ranging from 1.9 to 5.3 l/min/m(2). Four patients had periodic CI <2.4 l/min/m(2). Eight patients showed SpO2 values < or =92, four of them in more than 15% of the observations. Six patients had an SvO2 <70% in more than 40% of the observations and two an SvO2 < 64% in more than 20% of the observations. CONCLUSIONS: This study is unique because hemodynamic reference data in cardiac surgery patients have not been published previously. The intra-patient variations were unexpectedly high in most hemodynamic variables and demonstrate the difficulties of using hemodynamic parameters as a guidance for treatment and indicate that goal-oriented therapy using currently accepted values may result in over-treatment in some patients.
Assuntos
Procedimentos Cirúrgicos Cardíacos/métodos , Hemodinâmica , Monitorização Fisiológica/estatística & dados numéricos , Complicações Pós-Operatórias/prevenção & controle , Cuidados Pré-Operatórios/métodos , Cuidados Pré-Operatórios/estatística & dados numéricos , Idoso , Pressão Sanguínea , Débito Cardíaco , Procedimentos Cirúrgicos Eletivos/métodos , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica/métodos , Oxigênio/sangueRESUMO
BACKGROUND: Excessive use of broad spectrum antibiotics is related to the spread of drug resistant bacterial strains in the community. AIM/METHODS: The effects of immediate testing for C reactive protein (CRP) and white blood cell count (WBC) on physicians' choices of antibiotic was investigated in patients with acute infection. Acutely febrile new outpatients were randomised into two groups: group 1 (147 patients) underwent CRP and WBC testing before initial consultation (advance testing). Prescriptions were compared with those in group 2 (no advance testing; 154 patients). RESULTS: In non-pneumonic acute respiratory tract infections, 61 (58%) and 122 (91%) of group 1 and 2 patients were prescribed antibiotics, respectively. Cefcapene pivoxil (third generation cephalosporin) and amoxicillin were the most frequently chosen drugs for group 1 and 2, respectively. Total prescriptions of newer, extended spectrum antibiotics (cefcapene pivoxil and clarithromycin (advanced macrolide)) were reduced by 25% in group 1, although they increased in rate (41 (67%) v 55 (45%) prescriptions) because of the decreased prescription of amoxicillin. In group 1, cefcapene pivoxil was preferentially selected when WBC values were greater than 9 x 10(9)/litre. Prescription shifted to macrolides (mainly clarithromycin) in patients without leucocytosis. Patient treatment outcome did not significantly differ between the two groups. CONCLUSIONS: The availability of CRP and WBC data during initial consultation greatly reduced prescription of amoxicillin, but had a lesser effect on newer, potent, broad spectrum antibiotics.
Assuntos
Antibacterianos/administração & dosagem , Infecções Bacterianas/diagnóstico , Proteína C-Reativa/análise , Febre/microbiologia , Padrões de Prática Médica , Doença Aguda , Adulto , Amoxicilina/administração & dosagem , Infecções Bacterianas/sangue , Infecções Bacterianas/tratamento farmacológico , Biomarcadores/sangue , Cefalosporinas/administração & dosagem , Claritromicina/administração & dosagem , Febre/sangue , Humanos , Japão , Contagem de Leucócitos , Pessoa de Meia-Idade , Ambulatório Hospitalar , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/tratamento farmacológico , Resultado do TratamentoRESUMO
Results and experiences two years after the introduction of off-pump coronary artery bypass (OPCAB) are presented. The material includes 95 patients, where 24 patients had a high preoperative risk due to unstable angina, concomitant diseases or relative contraindications to conventional bypass surgery. Per- and postoperative course was characterized by low morbidity with ultra fast track recovery, no detectable levels of coronary enzyme release in the majority of patients, no reoperations for bleeding and early discharge from the hospital. There were two in-hospital deaths, both patients from the high risk group, where one patient died due to a preoperative myocardial infarction, while the other death was not related to cardiac disease. Follow-up results were fully satisfactory, where 86% of the patients were free from anginal symptoms three months after surgery. As a consequence of these positive experiences, OPCAB surgery is offered to an increasing number of patients, currently 25% of our CABG procedures.
Assuntos
Ponte de Artéria Coronária/métodos , Doença das Coronárias/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Adulto , Idoso , Contraindicações , Doença das Coronárias/diagnóstico , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de RiscoRESUMO
Correct assessment of vessel cross-sectional area (CSA) is essential for reliable cardiac output (CO) measurements by means of pulsed Doppler echocardiography. In 23 patients who underwent coronary artery bypass grafting (CABG) the main pulmonary artery CSA and diameter changes were assessed by epicardial two-dimensional echocardiography using a 7.5 MHz cm2 transducer. Our data indicate that the shape of the pulmonary artery changes over time. Time averaged CSA ranged from 3.51 to 8.29 cm2 (mean 5.04 cm2; SD 1.3 cm2) and the distensibility varied from 13% to 33% (mean 23%; SD 5%). The limits of agreement for the CSA calculated from the most suitable diameter (when assuming vessel circularity) and the corresponding traced CSA (reference value) during peak systole were -0.16 +/- 0.56 cm2 (mean +/- 2SD). In this idealized set-up (not clinically implementable) the maximal discrepancy between the calculated and traced CSA was 12% and 17% during peak systole and diastole, respectively. Therefore, a potential error in CO determination is incurred if CSA is assessed from a single diameter.
Assuntos
Débito Cardíaco/fisiologia , Artéria Pulmonar/diagnóstico por imagem , Adulto , Idoso , Ecocardiografia Doppler , Feminino , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Pulmonar/fisiopatologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resistência VascularRESUMO
OBJECTIVES: To evaluate whether the application of heparin treated circuits for elective coronary artery surgery improves postoperative recovery, a European multicenter randomised clinical trial was carried out. METHODS: In 11 European heart centers, 805 low-risk patients underwent cardiopulmonary bypass (CPB) with either an untreated circuit (n = 407) or an identical but heparin treated circuit (n = 398, Duraflo II). RESULTS: Significant differences were found among participating centers with respect to patient characteristics, blood handling procedures and postoperative care. The use of heparin treated circuits revealed no overall changes in blood loss, blood use, time on ventilator, occurrence of adverse events, morbidity, mortality, and intensive care stay. These results did not change after adjustment for centers and (other) prognostic factors as analysed with logistic regression. In both groups no clinical or technical (patient or device related) side effects were reported. Because female gender and aortic cross clamp time appeared as prognostic factors in the logistic regression analysis, a subgroup analysis with these variables was performed. In a subpopulation of females (n = 99), those receiving heparin treated circuits needed less blood products, had a lower incidence of rhythm disturbances and were extubated earlier than controls. In another subgroup of patients with aortic cross clamp time exceeding 60 min (n = 197), the amount of patients requiring prolonged intensive care treatment (> 24 h) was significantly lower when they received heparin treated circuits versus controls. CONCLUSION: These findings suggest that improved recovery can be expected with heparin treated circuits in specific higher risk patient populations (e.g. females) and when prolonged aortic cross clamp time is anticipated. Further investigations are recommended to analyses the clinical benefit of heparin treated circuits in studies with patients in different well defined risk categories and under better standardised circumstances.
Assuntos
Ponte de Artéria Coronária , Doença das Coronárias/cirurgia , Circulação Extracorpórea/instrumentação , Heparina , Adulto , Idoso , Perda Sanguínea Cirúrgica/fisiopatologia , Perda Sanguínea Cirúrgica/prevenção & controle , Ponte de Artéria Coronária/mortalidade , Doença das Coronárias/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/mortalidade , Complicações Pós-Operatórias/prevenção & controle , Propriedades de Superfície , Análise de Sobrevida , Resultado do TratamentoRESUMO
UNLABELLED: Despite high plasma levels of heparin during cardiopulmonary bypass surgery, activation of the coagulation system has been reported. We hypothesize that the coagulation system activity most appropriately could be assessed by molecular markers of thrombin generation. The aim of the present study was to describe the changes in thrombin generation during CPB, using prothrombin fragment F1 + 2 (F1.2) as an indicator and evaluate different blood sampling regimens for interpretation of the F1.2 measurements. Twenty patients, operated under extracorporeal circulation with coronary artery bypass grafting (CABG), comprised the study material. The heparin levels were maintained above 2.5 IU/ml throughout the bypass procedure and the functional AT-III level was kept above 0.5 U/ml. Despite of this anticipated inactivation of the coagulation system, the concentrations of F1.2 and FpA increased throughout CPB, particularly after release of the aortic crossclamp. F1.2 and FpA correlated significantly (R = 0.69). No statistically significant correlation was found between F1.2 formation rate and age, bodyweight, baseline ACT, ACT after 200 IU heparin/kg, average heparin concentration during CPB or average AT-III level during CPB. CONCLUSIONS: Thrombin formation seems to be a continuous process during CPB despite adequate heparinization. The pattern of thrombin generation can be assessed most appropriately in terms of F1.2 generation rate. Extraordinary high levels of F1.2 were seen after release of the aortic crossclamp, indicating that the periods before and after aortic crossclamping should be evaluated separately.
Assuntos
Ponte Cardiopulmonar , Monitorização Intraoperatória , Fragmentos de Peptídeos/análise , Protrombina/análise , Trombina/biossíntese , Adulto , Idoso , Anticoagulantes/administração & dosagem , Anticoagulantes/farmacologia , Antitrombina III/análise , Aorta , Biomarcadores , Coagulação Sanguínea/efeitos dos fármacos , Coleta de Amostras Sanguíneas/métodos , Constrição , Feminino , Fibrinopeptídeo A/análise , Heparina/administração & dosagem , Heparina/farmacologia , Humanos , Masculino , Pessoa de Meia-Idade , Trombina/análiseRESUMO
OBJECTIVES: To validate the new CardioMed CM 4000 transit time ultrasound apparatus for intraoperative measurement of volume blood flow in vivo in man. DESIGN: Open, prospective series. MATERIALS: Thirteen patients undergoing in situ saphenous vein grafting for chronic critical leg ischaemia and 12 patients subjected to myocardial revascularisation with the internal thoracic artery as coronary bypass. METHODS: During operations, volume blood flows were measured simultaneously by exsanguination from the cut distal end of the in situ saphenous vein graft or the internal thoracic artery and by the transit time flowmeter equipment. In addition, the feasibility to detect arteriovenous fistula during in situ saphenous vein grafting was examined. RESULTS: Within the examined blood flow range, the volume blood flow determined by the transit time method corresponded to the directly measured blood flow. For in situ saphenous vein grafts: y = -2.4 + 0.95.x (r = 0.99; 35 measurements in 13 patients), and for internal thoracic artery grafts: y = -9.6 + 1.1.x (r = 0.99; 21 measurements in 12 patients), where y is blood flow determined by transit time, and x is directly measured blood flow by exsanguination (r = correlation coefficient) as calculated by the least squares regression method. Fistula detection was easy and swift. CONCLUSIONS: The transit time apparatus was simple to use during intraoperative settings and gave fast, precise measurements of volume blood flow.
Assuntos
Hemorreologia/instrumentação , Reologia/instrumentação , Ultrassonografia/instrumentação , Adulto , Idoso , Idoso de 80 Anos ou mais , Fístula Arteriovenosa/diagnóstico , Velocidade do Fluxo Sanguíneo , Volume Sanguíneo , Ponte de Artéria Coronária , Desenho de Equipamento , Estudos de Viabilidade , Feminino , Humanos , Isquemia/cirurgia , Perna (Membro)/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória/instrumentação , Estudos Prospectivos , Reprodutibilidade dos Testes , Veia Safena/transplante , Artérias Torácicas/transplanteRESUMO
Intraluminal movements of pulmonary artery catheters are seldom considered, although they may have a significant impact on flow measurement and safety. The purpose of this study was to document the movements of these catheters within the heart cycle, and to establish whether any patterns existed. We analyzed two-dimensional real time echocardiography cross-sectional images of the human pulmonary artery in 20 patients, plotting the position of the intra-arterial catheter frame-by-frame onto a standardized template. We found that movement of the catheter within the pulmonary artery occurred in a seemingly random pattern. There was no movement pattern to the inferior right of the vessel, an area known to have complex velocity profiles and erroneous velocity measurements. The catheter moved substantially throughout the heart cycle, occasionally quite close to the vessel wall. We observed significant movement of the pulmonary artery catheter throughout the heart cycle, without any predictable pattern. Although we did not specifically investigate the effect of these movements on cardiac output, they imply that intra-arterial Doppler flow measurements from the pulmonary artery may be inaccurate, since a stable catheter position, and hence, a sample volume, cannot be ensured. Further speculation can be made on the implications of these movements in regard to thermodilution cardiac output and safety.
Assuntos
Cateterismo de Swan-Ganz/métodos , Movimento (Física) , Artéria Pulmonar/diagnóstico por imagem , Adulto , Idoso , Débito Cardíaco , Cateterismo de Swan-Ganz/efeitos adversos , Ecocardiografia , Segurança de Equipamentos , Humanos , Pessoa de Meia-Idade , ReologiaRESUMO
A 43-year-old man with angina for 15 years underwent coronary angiography, which showed an anomalous origin of the right coronary artery (RCA) from the left sinus of Valsalva with a 30-40% fibrous stenosis in the proximal part of the artery, which was presumably responsible for the patient's symptoms. Myocardial scintigraphy (Tc-99 m Cardiolite) suggested reversible ischemia at the apex and the posterior wall of the ventricles. After coronary bypass and anastomosis of the right internal mammary artery (RIMA) to the middle segment of RCA, the patient was asymptomatic; however, a postoperative myocardial scintigraphy indicated that the myocardial ischemia was irreversible.