No abstract available.

BACKGROUND: Induction of anesthesia with a high dose of fentanyl and vecuronium decreases the heart rate and blood pressure. This study was designed to evaluate the effect of preinduction atropine on these hemodynamic changes in patients undergoing coronary artery bypass graft surgery (CABG). METHODS: Forty-one patients who underwent CABG were randomly divided into two groups. After insertion of a radial artery cannula and a Swan-Ganz catheter, normal saline 1 ml (control group, n = 20) or atropine 0.5 mg (atropine group, n = 21) was injected intravenously 1 min before the induction of anesthesia. Anesthesia was induced with a first dose of fentanyl (5-8 microgram/kg) and vecuronium (0.12 mg/kg) and a second dose of fentanyl (5-10 microgram/kg). The patient was then intubated. Hemodynamic variables were measured before the induction of anesthesia, 1 min after the administration of each drug during the induction of anesthesia and 5, 10, and 30 min after the intubation. RESULTS: There was no significant differences between the two groups in terms of demographic data except that the number of patients with diabetes mellitus was greater in the control group than in the atropine group. The number of patients treated for hypotension or bradycardia during the induction of anesthesia was greater in the control group than in the atropine group, but this was not statistically significant. Heart rates significantly decreased in the control group but were maintained in the atropine group without any significant tachycardia. Blood pressure significantly decreased in both groups. CONCLUSIONS: Intravenous injection of atropine before anesthetic induction in patients undergoing CABG attenuates the decrease in heart rate resulting from anesthetic induction with high dose fentanyl and vecuronium. However, it didn't prevent the decrease in blood pressure nor did it reduce the incidence of treatment for hypotension.
Anesthesia ; Atropine* ; Blood Pressure ; Bradycardia ; Catheters ; Coronary Artery Bypass* ; Coronary Vessels* ; Diabetes Mellitus ; Fentanyl* ; Heart Rate ; Hemodynamics* ; Humans ; Hypotension ; Incidence ; Injections, Intravenous ; Intubation ; Radial Artery ; Tachycardia ; Transplants ; Vecuronium Bromide*

Off-pump coronary artery bypass graft surgery (OPCAB) may be of benefit overall for the patient and surgical techniques for OPCAB have been developed markedly. The development of surgical techniques without severe hemodynamic instability allows surgeons to access to all coronary arteries. Hemodynamic instability due to the displacement and restraining of the heart and transient ischemia during anastomoses are major problems associated with OPCAB. The maintenance of stable hamodynamic and minimization of cardiac dysfunction during anastomosis should be stressed in the anesthesia for OPCAB. The baseline anesthetic methods and monitoring for OPCAB are the same as for conventional coronary artery bypass graft surgery (CABG). The temperature management is a significant problem and appropriate provision is needed for defibrillation and pacing during anastomosis because rhythm problems are not uncommon. Prevention and treatment of hypotension, low cardiac output, and dysrhythmia is a major focus of anesthetic management. Volume loading and Trendelenberg position is helpful maintaining cardiac output and perfusion pressure. If hemodynamic deterioration occurs, quickly progress to potent vasopressors/ inotropic agents. Treatment of myocardial ischemia must be guided by the patient's overall hemodynamic status. Therapies to consider include titrated beta-adrenergic blockers, increasing blood pressure to improve collateral flow, treating the spasm of native coronaries or arterial conduits, reversing Trendelenberg to reduce left ventricular filling and wall stress and shunting. Close observation for surgical field and open communication with surgeon is essential to predict the patients most likely to need above modalities and bearing similarities with anesthesia for CABG in mind will help the anesthesiologist to be more comfortable with anesthesia for OPCAB.
Adrenergic beta-Antagonists ; Anesthesia ; Blood Pressure ; Cardiac Output ; Cardiac Output, Low ; Coronary Artery Bypass ; Coronary Artery Bypass, Off-Pump* ; Coronary Vessels ; Heart ; Hemodynamics ; Humans ; Hypotension ; Ischemia ; Myocardial Ischemia ; Perfusion ; Spasm ; Transplants*

BACKGROUND: Increasing coronary perfusion pressure with phenylephrine is important treatment strategies for right ventricular dysfunction caused by pulmonary hypertension. We compared the effects of phenylephrine on systemic and pulmonary hemondynamics in patients with and without pulmonary hypertension. METHODS: Twenty patients undergoing a valvular replacement were divided into two groups according to pulmonary artery pressure (PAP): control group (mean PAP < 25 mmHg, n = 9) or pulmonary hypertension group (mean PAP > 25 mmHg, n = 11). When systolic blood pressure decreased below 100 mmHg after the induction of anesthesia, phenylephrine was infused to raise systolic blood pressure up to 30% and 50% over baseline. Hemodynamic variables were measured at each time. RESULTS: Phenylephrine failed to raise systolic blood pressure up to 50% above baseline in more than half of the patients with pulmonary hypertension in contrast to successful increases in all patients without pulmonary hypertension. However, the ratio of PAP to systolic blood pressure was significantly reduced in patients whose systolic blood pressure was successfully increased up to 50% over baseline in the pulmonary hypertension group whereas the PAP concomitantly increased as systolic blood pressure was increased in the control group. CONCLUSIONS: Phenylephrine couldn't increase systolic blood pressure in some patients with pulmonary hypertension unlike in control group and it seemed to occur more often in patients with greater the ratio of PAP to systolic blood pressure. The baseline systemic vascular resistance index was high and cardiacoutput was low in the pulmonary hypertension group and these conditions seemed to restrict the effect of phenylephrine.
Anesthesia ; Blood Pressure ; Hemodynamics* ; Humans ; Hypertension, Pulmonary* ; Perfusion ; Phenylephrine* ; Pulmonary Artery ; Vascular Resistance ; Ventricular Dysfunction, Right

BACKGROUND: Coronary artery bypass grafting without cardiopulmonary bypass (Off-Pump Coronary Artery Bypass Grafting, OPCAB) causes significant hemodynamic derangement by displacement of the beating heart. The purpose of this study was to analyze the hemodynamic changes caused in relation to grafted arteries by displacing the heart and stabilizing the coronary arteries in patients undergoing OPCAB. METHODS: Nineteen patients underwent OPCAB using two deep pericardial sutures and tissue stabilizers (Octopus Tissue Stabilization Syetem, Medtronic, USA). The hemodynamic variables were obtained after induction of anesthesia, after deep pericardial sutures, before and after anastomosis of each coronary artery during epicardial stabilizing, after sternal closure, and after postoperative 6 hours and 12 hours in the intensive care unit. RESULTS: The hemodynamic variables were maintained with the Trendelenburg position, volume loading and low dose vasopressors after deep pericardial stay sutures. Displacement of the heart and placement of the stabilizer on all coronary territories except the obtuse marginal artery before anastomosis showed no significant difference in hemodynamics compared with baseline. Positioning for the graft to the obtuse marginal artery decreased cardiac index (1.6+/-0.4 L/min/m2) and stroke index (27.6+/-9.9 L/beat/m2) and increased systemic vascular resistance (2318.9+/-673.7 dyne sec cm(-5)), resulting in hemodynamic compromise (P<0.01). There were no significant hemodynamic and electrocardiographic changes before or after grafting of other coronary arteries but there was a significant increase in cardiac index after postoperative 6 and 12 hours compared with baseline values (P<0.05). CONCLUSIONS: Although the complete revascularization of most coronary arteries is feasible on the beating heart without significant hemodynamic compromise with minimal vasopressor support, the positioning for the graft to the obtuse marginal artery needs special attention because two deep pericardial stay sutures and Octopus tissue stabilizers on the obtuse marginal artery territory induce significant hemodynamic disturbances.
Anesthesia ; Arteries ; Cardiopulmonary Bypass ; Coronary Artery Bypass ; Coronary Artery Bypass, Off-Pump* ; Coronary Artery Disease ; Coronary Vessels ; Electrocardiography ; Head-Down Tilt ; Heart* ; Hemodynamics* ; Humans ; Intensive Care Units ; Octopodiformes ; Stroke ; Sutures ; Transplants* ; Vascular Resistance

To evaluate the safety and effectiveness of the intraoperative phlebotomy with acute hemodilution and autologous transfusion as an approach to blood conservation during cardiac operation, 126 patients were grouped into autologous transfusion group(Group I, n=54), prospective control group(Group II, n=22), and retrospective control group(Group III, n=50). Intraoperative hemodilution was practiced in autologous transfusion group before extracorporeal circulation. After an extracorporeal circulation, the units of blood phlebotomized were transfused. Hematocrit, platelet count, PT(prothrombin time), PTT(partialthromboplastin time), MAP(mean arterial pressure), and amount of homologous transfusion were measured immediately after induction, during bypass, and at the intensive care unit. Blood loss was measured at 12 hours and 24 hours after arrival at intensive care unit. Incidence of hemologous transfusion was 62% in group I, 86.4% in group II, and 100% in group III. Patients received 2.2+/-0.4 units in group I, 4.1+/-0.8 units in group II and 6.7+/-0.5 units in group III. Coagulation studies showed no significant improvement in autologous transfusion group who received fresh autologous blood. There was no difference in blood loss postoperatively among 3 groupes. In conclusion, our data suggest that the use of autologous transfusion with hemodilution reduces usage of homologous blood in all cardiac surgery procedures.
Extracorporeal Circulation ; Heart* ; Hematocrit ; Hemodilution* ; Humans ; Incidence ; Intensive Care Units ; Phlebotomy ; Platelet Count ; Prospective Studies ; Retrospective Studies ; Thoracic Surgery*

Blood transfusions in open heart surgery become increasingly dangerous in recent years because of hepatitis and the AIDS virus. For this reason, blood saving methods must be considered when assessing the quality of cardiac surgery. To evaluate different blood saving methods, seventy two patients undergoing open heart surgery were divided into 3 groups. Aprotinin group(group I, n=35) and aprotinin with acute normovolemic hemodilution group (group II, n=15) were compared with prospective control group (group III, n=22). We administered the serine protease inhibitor aprotinin in high dosage(loading dose of 4mg/kg and maintaing dose of 1mg/kg/hr) to group I, and II patients. Acute normovolemic hemodiluation(ANH) was done before heparinization in group II. One to three units of blood could be withdrawn with a desired hematocrit of 30%. After an extracorporeal circulation (ECC), autologous transfusion was undertaken. Hematocrit, platelet count, and partial thromboplastin time(PTT) were measured immediately after induction, during bypass and at the intensive care unit. Amount of blood loss was measured in 12 and 24 hours after arrival at an intensive care unit. Amount of homologous transfusion was counted in postbypass period and 12 hours after arrival at an intensive care unit. Hematocrit was elevated in group II(p<0.05) after ECC Platelet counts were elevated and partial thromboplastin time was prolonged in group II in postbypass period and 12 hours after arrival at an intensive care unit compared with group I and III. Postoperative blood loss was 560.4+/-272.5cc in group I, and 282.0+/-98.6cc in group II, 819.3+/-428,0cc in group III. The use of homologus transfusion(packed red cells and fresh frozen plasma) in group I could be reduced by 49 & 66% and group II by 73 & 84% compared with group III. In conclusion our study suggests that administration of high-dose aprotinin is effective in reducing intraoperative and postoperative bleeding and therefore reduces transfusion requirement. In addition, combination of ANH and aprotinin can further reduce homologous blood usage.
Aprotinin* ; Blood Transfusion ; Extracorporeal Circulation ; Heart* ; Hematocrit ; Hemodilution* ; Hemorrhage ; Heparin ; Hepatitis ; HIV ; Humans ; Intensive Care Units ; Partial Thromboplastin Time ; Platelet Count ; Postoperative Hemorrhage ; Prospective Studies ; Serine Proteases ; Thoracic Surgery* ; Thromboplastin

This study was designed to evaluate the possibility of esmolol to attenuate the cardiovascular reflex due to the induction of general anesthesia, tracheal intubation and/or surgical stimulations during open heart surgery. Esmolol was infused continuously to each patient by 150 ug/kg/min from 2 minutes prior to the completion of the induction of anesthesia and then by 75 ug/kg/min throughout the skin-incision. In patients undergoing coronary bypass grafts, esmolol group of 5 individuals did not show any significant change in hemodynamics in contrast to the control group of 5 individuals, which showed singificant decreases in systolic and mean arterial pressure(p<0.05). The plasma concentrations of the catecholamines in the esmolol group were not significantly different from those in control. In patients undergoing valve replacement, esmolol group did not show any significant difference in hemodynamics from control. The plasma concentrations of the catecholamines in the esmolol group were not changed by the anesthetic and surgical procedures in contrast to the control group, which showed 3 times increase (p<0.05) in norepinephrine level and 8 times increase (p<0.05) in epinephrine level. The results of these experiments demonstrate that esmolol can suppress the hemodynamic refiex and catecholamine-release due to the stimulations of anesthetic and surgical procedures under the general anesthesia by a high concentration of fentanyl, and that esmolol can be administered safely to attenuate the hazardous sympathetic reflexes.
Anesthesia ; Anesthesia, General ; Catecholamines ; Epinephrine ; Fentanyl ; Heart* ; Hemodynamics* ; Humans ; Intubation ; Norepinephrine ; Plasma ; Reflex ; Thoracic Surgery ; Transplants

No abstract available.
Anesthesiology* ; Education*

BACKGROUND: There has been no report about the effects of blood pressure (BP) on the change of blood flow (BF) to major organs when pump flow is maintained during cardiopulmonary bypass (CPB). We evaluated the changes of the BF and oxygen consumption of major organs when BP was controlled by vasopressors or vasodilators during CPB. METHODS: Carotid, femoral, hepatic and renal arteries and veins were exposed and arteries were cannulated for pressure monitoring, except the hepatic artery and arteries on the opposite side were exposed for the measurement of BF in 7 dogs. Temperature was lowered to 30oC after initiation of CPB and phenylephrine or sodium nitroprusside was infused to increase or decrease BP about 30% under the same pump flow. BP and BF were measured before CPB, before the infusion of drugs and when BP was changed by vasoactive drugs. Blood gas analyses were performed from the artery and each vein while the BF was measured. RESULTS: The change of BP didn't affect carotid and renal BF. However, hepatic BF decreased about 50% when BP was reduced and femoral BF changed in the opposite way of BP change. Oxygen consumption of each organ wasn't influenced by BP. CONCLSIONS: When pump flow was constantly maintained, changes in BP redistributed BF to major organs but didn't affect oxygen consumption. The brain and kidney have the ability of autoregulation of BF unlike the liver or legs. Hepatic BF was dependent on perfusion pressure and a decrease in BP by vasodilators during CPB may be not good for the liver.
Animals ; Arteries ; Blood Gas Analysis ; Blood Pressure ; Brain ; Cardiopulmonary Bypass* ; Dogs ; Hepatic Artery ; Homeostasis ; Kidney ; Leg ; Liver ; Nitroprusside ; Oxygen Consumption ; Perfusion* ; Phenylephrine ; Renal Artery ; Vasodilator Agents ; Veins