The Effects of Intravenous Thiopental Injection on Jugular Venous Oxygen Saturation (SjVO2) during Cerebral Aneurysm Surgery / 대한마취과학회지

BACKGROUND: Thiopental has a profound impact on the cardiovascular system. The effects of hemody namics after intravenous thiopental on the balance of cerebral metabolism with cerebral blood flow is unknown. The purpose of this study was to monitor hemodynamic change, cerebral arterial-jugular venous oxygen content difference (AVDO2) and jugular venous oxygen saturation (SjVO2) after a thiopental injection for brain protection during cerebral aneurysm surgery. METHODS: Twenty patients received a standard anesthetic consisting of isoflurane, vecuronium and fentanyl with a PaCO2 of 30 35 mmHg. Hemodynamics, arterial and jugular venous blood gases were measured at 3 time points:I; Just before thiopental injection; II; Electroencephalographic (EEG) burst suppression after a 4 5 mg/kg intravenous thiopental injection; and III; EEG recovery. RESULTS: Intravenous thiopental (4 5 mg/kg) induced an EEG burst suppression for 6.5 +/- 1.7 minutes. Hemodynamics and arterial blood gas analysis were not significantly different among the different time points, but mean arterial pressure (68.4 +/- 7.2 mmHg) and systemic vascular resistance (1027.0 +/- 300.9 dynes sec/cm5) in II were significantly (P < 0.05) decreased compared with I (84.3 +/- 9.6, 1169.1 +/- 304.5) and III (89.1 +/- 10.6, 1288.6 +/- 426.1). SjVO2 (71.6 +/- 11.8%) was significantly (p < 0.05) decreased within the normal value compared with I (75.1 +/- 5.6) and III (76.1 +/- 10.1), but AVDO2 was not significantly different among the 3 time points. There was no evidence of cerebral ischemia or infarction in computed tomographic (CT) findings of the 20 patients after surgery. CONCLUSIONS: Hemodynamics after 4 5 mg/kg intravenous thiopental do not modify the balance ofcerebral oxygen metabolism with cerebral blood flow in patients undergoing cerebral aneurysm surgery.

Effects of Intravenous and Epidural Patient-Controlled Analgesia on Postoperative Pain and Knee Rehabilitation after a Unilateral Total Knee Replacement / 대한마취과학회지

BACKGROUND: Postoperative pain is a major concern after a total knee replacement (TKR). It hinders early intense physical therapy, the most influential factor for good postoperative knee rehabilitation. The purpose of this study was to compare intravenous patient-controlled analgesia (IV-PCA) using morphine and continuous ketorolac IV infusion with patient-controlled epidural analgesia (PCEA) using morphine and continuous bupivacaine infusion in terms of analgesic efficacy and postoperative knee rehabilitation after a unilateral TKR. METHODS: Eighteen patients undergoing a unilateral total knee replacement were randomly allocated to one of the two groups. In group IV-PCA (n = 9), 30 min before the end of surgery, patients received ketorolac 30 mg IV bolus followed by continuous infusion with ketorolac (5 mg/h) and IV-PCA with morphine (20microgram/kg, lockout 10 min). In group PCEA (n = 9), 30 min before the end of surgery, patients received 2 mg morphine bolus followed by continuous infusion with 0.1% bupivacaine (2 ml/h) and PCEA with morphine (1 mg, lockout 15 min). RESULTS: There were significant differences in visual analogue scale scores at the first 2-hours after the unilateral TKR, cumulative morphine consumption and number of postoperative days required to obtain 90o knee flexion. CONCLUSIONS: PCEA using a morphine-bupivacaine combination provided better pain relief and faci litated the continuous passive motion more than IV-PCA using a morphine-ketorolac combination. This results in possible faster postoperative knee rehabilitation.

The Influence of High- and Low-Dose Aprotinin on Thromboelastography in Coronary Artery Bypass Grafting Surgery / 대한마취과학회지

BACKGROUND: The protease inhibitor aprotinin reduces blood loss and homologous blood usage after a cardiac operation. The aim of the present study was to investigate the effect of low- and high-dose aprotinin on thromboelastography (TEG) variables and to examine the relationship between the clinical effect of aprotinin and the TEG variables in coronary artery bypass grafting surgery (CABG). METHODS: Twenty-three patients scheduled for an elective CABG were randomly assigned to receive either high does (group H, n = 12) or low does (group L, n = 11) aprotinin. TEG variables, and a coagulation profile test at baseline and arrival in ICU were performed. Amount of blood loss, homologous blood transfusion and heparin requirements were measured. RESULTS: In group L, there were significant increases in r time and k time and significant decreases in MA and alpha angle after aprotinin administration. In group H, just k time after aprotinin administration was significantly increased compared with baseline data. There were no significant differences in amount of blood loss and allogenic blood transfusions between the two groups. There was not a significant correlation between TEG variables and amount of blood loss in both groups. Interestingly a siginificant negative correlation between the length of cardiopulmonary bypass and MA was noted in group H (r = -0.63; P < 0.05). CONCLUSIONS: In CABG patients, aprotinin preserves platelet function more significantly in the high-dose aprotinin group. In addition, TEG variables indicated a later clot formation in the low dose aprotinin group.

Adrenergic Receptors and Cardiovascular System / 대한구급학회지

No abstract available

Changes of Lung Compliance and Gas Exchange after Modified Ultrafiltration in Pediatric Cardiac Surgery / 대한마취과학회지

BACKGROUND: Pediatric cardiopulmonary bypass (CPB) often results in increased capillary permeability and accumulation of excess total body water, which can lead to multiple organ dysfunctions. Recently, modified ultrafiltration (MUF) has been used during pediatric cardiac surgery to limit various deleterious effects of CPB. We investigated the effects of MUF on lung compliance and gas exchange in pediatric open heart operations. METHODS: Fifteen pediatric open heart surgery patients were evaluated. Lung compliance (dynamic compliance), arterial oxygen tension (PaO2), arterial to end-tidal carbon dioxide tension difference (Pa-ETCO2), systolic blood pressure (SBP), heart rate, and hematocrit (Hct) were measured. Measurements were made after induction of anesthesia, after CPB, after MUF and after sternal closure. RESULTS: Lung compliance, PaO2, SBP and Hct increased significantly after MUF compared to after CPB. After sternal closure, lung compliance decreased significantly from the value following MUF. PaO2, SBP, Hct decreased significantly after CPB compared to the values obtained after induction of anesthesia. Pa-ETCO2 and heart rate did not change significantly. CONCLUSIONS: Modified ultrafiltration increases lung compliance, PaO2, SBP and Hct. MUF is an excellent option for improving cardiopulmonary function immediately following pediatric cardiopulmonary bypass.

The Effect of Acute Normovolemic Hemodilution on Cardiopulmonary Bypass in Coronary Artery Bypass Grafting Surgery / 대한마취과학회지

BACKGROUND: Systemic arterial hypotension is relatively common following initiation of cardiopulmonary bypass (CPB). Decreased blood viscosity is induced by acute normovolemic hemodilution (ANH) and by the use of crystalloid oxygenator prime. The purpose of this paper is to study the effect of ANH on mean arterial pressure, perfusion flow index and PaO2/FiO2 upon initiation of CPB, and on homologous blood usage during CPB in coronary artery bypass grafting (CABG) surgery. METHODS: We reviewed 30 patients constituting an ANH group, and 30 patients in a control group who had undergone CABG surgery within the past 2 years. In the ANH group, 1 or 2 units of fresh autologous whole blood were sequestrated following induction of anesthesia. We compared mean arterial pressure, perfusion flow index, PaO2/FiO2, and hematocrit on the initiation of CPB, and homologous blood usage during and post CPB periods between the groups. RESULTS: Upon initiation of CPB, hematocrit in the ANH group was significantly less than in the control group, but there was no significant difference in mean arterial pressure, perfusion flow index or PaO2/FiO2 between the groups. The use of homologous blood during CPB in the ANH group was not significantly higher than in the control group. CONCLUSIONS: Acute intraoperative normovolemic hemodilution in CABG surgery was safely performed without significant hypotension and increased homologous blood usage during CPB.

Deep Hypothermic Circulatory Arrest for Management of Giant Aneurysm of Basilar Artery in Coronary Artery Disease: A case report / 대한마취과학회지

Giant aneurysms present challenging problems with conventional techniques because the lesion is in a difficult area or lacks a definitive aneurysmal neck. For the safety of operation and protection from cerebral ischemia, deep hypothermic circulatory arrest and cerebral protection with barbiturate is considered a useful technique. But deep hypothermia may produce myocardial depression and coagulopathy with high mortality. We report our experience with cardiopulmonary bypass with deep hypothermic circulatory arrest for the management of a patient with giant aneurysm of basilar artery and mild coronary artery stenosis. No significant complications were related to the technique of cardiopulmonary bypass with deep hypothermic circulatory arrest.

Deep Hypothermic Circulatory Arrest for Management of Giant Aneurysm of Basilar Artery in Coronary Artery Disease: A case report / 대한마취과학회지

Giant aneurysms present challenging problems with conventional techniques because the lesion is in a difficult area or lacks a definitive aneurysmal neck. For the safety of operation and protection from cerebral ischemia, deep hypothermic circulatory arrest and cerebral protection with barbiturate is considered a useful technique. But deep hypothermia may produce myocardial depression and coagulopathy with high mortality. We report our experience with cardiopulmonary bypass with deep hypothermic circulatory arrest for the management of a patient with giant aneurysm of basilar artery and mild coronary artery stenosis. No significant complications were related to the technique of cardiopulmonary bypass with deep hypothermic circulatory arrest.

A Comparison between 20% Albumin and 10% Pentastarch in Priming fluid for Cardiopulmonary bypass / 대한마취과학회지

BACKGROUND: Since hydroxyethyl starch has colloidal properties closely approximating those of human albumin, it is considered to be a good plasma volume expander. Pentastarch is a hydroxyethyl starch similar to hetastarch, but with lower average molecular weight and molar substitution ratio. These characteristics result in enhanced enzymatic hydrolysis, faster renal elimination and less effect on coagulation. This study was designed to evaluate the safety and clinical efficacy of 10% pentastarch in priming fluid for cardiopulmonary bypass compared with that of 5% albumin. METHODS: Thirty- two adult patients undergoing elective cardiac surgery were randomized into two groups. Sixteen patients received 500 ml of 10% pentastarch and sixteen patients received 100 ml of 20% albumin in a bloodless priming solution for cardiopulmonary bypass. The fluid balance, coagulopathy and organ functions(cardiac, pulmonary and renal) were evaluated at several time intervals. RESULTS: There were no differences between the two groups in operation and bypass time, chest tube drainage and blood usage. The measured prothrombin time, partial thromboplastin time and platelet count of pentastarch group were not significantly different from those of the albumin group at each time interval(p<0.05). We did not find any differences of statistical significance in hemodynamic data, serum osmolarity, pulmonary shunt and BUN between the two groups(p<0.05). CONCLUSIONS: Our study suggests that 10% pentastarch can be used safely and effectively as cardiopulmonary bypass prime in cardiac surgery.

Transesophageal Doppler Echocardiography in the Evaluation of Mitral Bileaflet Mechanical Prostheses: Comparative Studies between Sorin Bicarbon and ATS Valve Prostheses in Mitral Valve Replacement

BACKGROUND: The intraoperative TEE is frequently used as a preoperative diagnostic technique and for intraoperative assessment of surgical results. However, the clinical studies regarding assessment of mitral prostheses in the immediate postbg>ass period by TEE have been few, and there is no comparative data between curved(Sorin Bicarbon) and rotatable flat(ATS) bileaflet mechanical prostheses. The purpose of this study is to compare forward flow hemodynamics and complications including regurgitation between Sorin Bicarbon and ATS mitral prostheses by using Doppler and color-flow imaging TEE. METHOD: 23 patients with Sorin Bicarbon(Group I) and 16 patients with ATS(Group II) were studied by transesophageal Doppler echocardiography in the operating room. We measured the peak velocity & gradient, mean velocity 8c gradient and mitral valve area by pressure halt-time method after replacement of mitral prosthesis using Doppler echocardiography and determined the paravalvular regurgitation using color-How imaging. All transesophageal studies were performed about 20 minutes after termination of the cardiopulmonary bypass. RESULTS: There were no statistical differences(p<0.05) between the two groups in Doppler parameters. Mean transmitral gradient of Group [(2.31.2mmHg) was same as Group II. Mean mitral valve area(same as effective oriface area) calculated by pressure half-time method was 3.1+/-0.6 vs 3.0+0.9cm in Group I vs II. There was one prosthetic malfunction in Group II whose peak and mean gradient were 13 and 5mmHg respectively, and the mitral valve area was 2.8cm. Paravalvular and transvalvular regurgitation were not seen in both groups in operating room. CONCLUSION: In this study, we evaluated functional differences between curved(Sorin Bicarbon) vs flat(ATS), bileaflet mechanical prostheses in MVR by using Doppler and color flow imaging TEE. We conclude that both valves provided excellent hemodynamic profiles and there were no significant functional differences between them. Valve-related mechanical complications in both will need further studies.

Changes in Pulmonary Arterial Pressure and Pulmonary Vascular Resistance after Mitral Valve Replacement / 대한마취과학회지

As the mitral valve disease becomes long-standing, the patient may develop pulmonary hypertension. It was reported that after surgical correction, the elevated pulmonary vascular resistance(PVR) would fall quickly in association with the fall in left atrial pressure(LAP). This study was performed to evaluate the changes in mean pulmonary artery pressure(PAP) and PVR immediately after mitral valve replacement(MVR). Fifty six patients undergoing mitral valve replacement(MVR) were divided into two groups on the basis of the presence or absence of significant pulmonary hypertension, defined as a resting mean pulmonary arterial pressure greater than 30mmHg. After induction of anesthesia, PAP, PVR, cardiac output(CO) were measured and compared with values in postbypass period. PAP and PVR were significantly decreased(PAP from 39.64+/-1.88 to 29.18+/-1.65 mmHg, P 0.001, PVR from 6.16+/-1.14 to 3.53+/-0.62 units, P or = 30mmHg, n=23), whereas not changed in Group I(PAP30 mmHg, n=33)(P<0.05). Persistance of an elevated PVR may cause right ventricular failure and low-output syndrome, so that an attempt to reduce the PVR is needed postoperatiavely. This study demonstrated that the PAP and PVR fall significantly after MVR especially in patients with severe pulmonary hypertension.

Effect of Esmolol on the Hemodynamics and Catecholamine-Release During Open Heart Surgerry / 대한마취과학회지

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.

Effects of Intraoperative Hemodilution and Administration of Aprotinin on Blood Loss During Open Heart Surgery / 대한마취과학회지

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.

Effects of Perioperative Colliction of Blood and Acute Normovolemic Hemodilution on Requirement of Homologous Transfusion During Open Heart Surgery / 대한마취과학회지

This study was designed to investigate the effect of preoperative collection of blaod and acute normovolemic hemodilution(ANH) on the requirement of homologous transfusion, perioperative blood loss and hematological parameters in patients undergoing open heart surgery. Ninety two adult patients for elective open heart surgery were randomly assigned to one of three groups. Group I, ANH group, had blood withdrawn to a hematocrit of 33%o after induction of anesthesia(n =54). In Group II preoperative collection of blood in accordance with hospital protocol and ANH were performed(n=16). Ciroup III was control group(n=22). Autologous blood was replaced post bypass. The patients whose hematocrit fell below 25% were transfused with homologous blood. The use of homologous transfusion was 2.2+/-0.4 units in group I, 0.1+/-0.1 units in group II and 4.1+/-0.8 units in group III. Requirement of homologous transfusion in group II was reduced compared with group II and III with statistical significance(P<0.05). There was statistical significance between group I and group III(P<0.05) in homologous transfusion. Postoperative blood loss was 760.7+/-74.6 ml in group I, 675.6+101.5 ml in group II and 819.3+/-91.3 rnl in group III. There was no statistical significance among 3 groups. There was no difference in hematocrit or platelet count, and total blood loss on immediately post surgery or on day 1. Our data show that preoperative collection of blood and ANH can reduce the amount of homologous transfusion.

The Antagonism Effects of Neostigmine on Vecuronium - induced Neuromuscular Blockade in Renal Failure Patients / 대한마취과학회지

The elimination of most anticholinesterases depends on the kidney, even if the main organ for their metabolism is the liver. Renal excretion of pyridostigmine, edrophonium and neostigmine accounts for 15%, 70% and 50%, respectively. In the absence of renal function, the serum half-life of neostigmine is prolonged, its plasma clearance is decreased However, the pharmacodynamics of neostigmine have not been determined in renal failure. This study was designed to compare the neostigmine dynamics in 18 patients with normal renal function to that in 18 patients with renal failure(Group I & II, respectively). Using the flexor carpi ulnaris EMG via ulnar nerve stimulation with Train-Of-Four(TOF) under the constant infusion of vecuronium to produce about 85%-twitch depression, the responses of neostigmine with three different doses were obtained. The results are follows; 1) The constant infusion rates of vecuronium to maintain sbout 15&-twitch height prior to the administration of neostigmine showed no significant difference between two groups. 2) Immediately prior to each dose of neostigmine, the mean values of twitch heights were 11.7 to 13.7%. 3) There was no significant difference in the onset time, maximum twitch responses and antagonism effects between two groups in respect to each same dose of nesotigmine. 4) The duration of neostigmine with the half of ED only in Group II was significantly longer than that in Group I, even if the durations with the other doses in Group II were not significantly longer than those in Group L These results suggest that the reversal effect of neostigmine to vecuronium-induced block- ade may be outlasted in patients with renal failure and the prolongation of neostigmine effeet may render some benefits to reverse the relaxants which have the limitation of its elimination in this patients.