Effect of cardiopulmonary bypass on pulmonary clearance of adrenomedullin in humans

BACKGROUND

Adrenomedullin is a potent vasodilatory peptide and its plasma concentration increases after cardiopulmonary bypass. We analyzed the contribution of the lung to the disposition of adrenomedullin before and after cardiopulmonary bypass in humans.

METHODS

Thirty-five patients undergoing cardiac surgery with cardiopulmonary bypass were studied. Bloods were sampled from the pulmonary artery and left atrium at the following times: prior to systemic heparinization, during pulmonary reperfusion and after cardiopulmonary bypass. Plasma concentrations of total and mature adrenomedullin were measured using an immunoradiometric assay kit specific for human adrenomedullin. Intermediate adrenomedullin was calculated as the difference between total adrenomedullin and mature adrenomedullin.

RESULTS

Before cardiopulmonary bypass, mature and intermediate adrenomedullin concentrations were reduced by the pulmonary circulation by approximately 30% and 20%, respectively. However, these effects were not observed during pulmonary reperfusion. Mature, but not intermediate, adrenomedullin was reduced after cardiopulmonary bypass. Furthermore, pulmonary clearance quantity of mature adrenomedullin was significantly enhanced after cardiopulmonary bypass.

CONCLUSION

These results indicate that cardiopulmonary bypass temporally impairs the pulmonary clearance of mature and intermediate adrenomedullin, but clearance of mature, not intermediate adrenomedullin is enhanced after cardiopulmonary bypass.

Prospective analysis of percutaneous central venous catheterization in infants <4.0 kg undergoing cardiac surgery

Our previous study showed that the success rate of cannulation of the internal jugular vein (IJV) was significantly decreased in infants weighing less than 4.0 kg. We prospectively evaluated results of central venous catheterization in 101 infants weighing less than 4.0 kg undergoing cardiac surgery. The first attempt was routinely performed on the right IJV. If the first attempt failed, the anesthesiologist was free to choose the cannulation site. We examined the effects of patient weight and the experience of the anesthesiologist on successful central catheterization and efficacy of the external jugular vein (EJV) if the first attempt failed. The first right IJV cannulation was successful in 53 infants (52.5%) and the overall successful catheterization rate was 82.2%. Success rates of cannulation of the right IJV, left IJV, and EJV were 64, 13, and 6%, respectively. Body weight contributed significantly to successful catheterization, but the experience of the anesthesiologist did not. These results suggest that EJV cannulation improves the successful central catheterization in infants weighing less than 4.0 kg if IJV cannulation fails. Body weight of an infant, but not the experience of the anesthesiologist, contributed to successful catheterization in this patient population.

What factors are associated with hyperlactatemia after cardiac surgery characterized by well-maintained oxygen delivery and a normal postoperative course? A retrospective study

BACKGROUND

and objective The purpose of this study was to investigate retrospectively what factors contribute to the development of the type of hyperlactatemia which may follow cardiopulmonary bypass despite well-maintained oxygen delivery and a normal perioperative course.

METHODS

The medical records of 124 patients undergoing elective cardiac surgery using cardiopulmonary bypass were reviewed. The patients were divided into a hyperlactatemia group (n=34), where the serum lactate concentration was > 5.0 mmol L(-1) perioperatively, and a normal lactatemia group (n=90), which comprised the remaining patients.

RESULTS

The duration of cardiopulmonary bypass in the hyperlactatemia group was significantly longer than for the normal lactatemia group. Significant differences of lactate concentrations between the groups, and significant elevations of serum lactate had been observed after the start of cardiopulmonary bypass. Oxygen extraction rates were significantly reduced during the period of cardiopulmonary bypass but, on the contrary, increased in the hyperlactatemia group after surgery. The area under the curve of mean arterial pressure consisted of 5-min interval plots during the initial period of cardiopulmonary bypass in the hyperlactatemia group. This was significantly smaller than for the normal lactatemia group. Weakly significant correlations between maximal lactate and duration of cardiopulmonary bypass, and especially the area under the curve, were observed.

CONCLUSIONS

It is suggested that the pathophysiology observed is based on impairment of tissue oxygen utilization. The duration of cardiopulmonary bypass and especially the occurrence of hypotension at the start of the bypass period appears to be related to the development of lactic acidosis.

[Intraoperative assessment of cardiac function with transesophageal echocardiography during the Batista operation]

We experienced anesthetic management for six cases of the Batista operation and measured cardiac function before and after cardiopulmonary bypass (CPB) with transesophageal echocardiography. In the successful three patients, left ventricle ejection fraction and ejection time were maintained over 25% and 200 msec after CPB, respectively. In the other three resulting in implantation of left ventricular assist device, ejection fraction remained below 20% and ejection time under 200 msec after CPB. Intraoperative transesophageal echocardiography may be useful not only for monitoring of cardiac function but also for the prediction of prognosis.

Effects of autologous fresh platelet concentrate on haemostasis in cardiac reoperations

The aim of this study was to determine whether autologous fresh platelet concentrate (PC) significantly improves haemostasis in cardiac reoperations compared with autologous fresh whole blood (WB). Forty-eight patients who had elective cardiac reoperations with a low-dose aprotinin priming regimen were divided into two groups. The amount of allogeneic blood transfusion was less in patients who were harvested 15 units of PC (Group PC; n = 24) before cardiopulmonary bypass (CPB) than patients who were harvested 400 ml of WB (Group WB; n = 24). The amount of mediastinal drainage for 12 h in intensive care units were significantly reduced in Group PC compared with Group WB (435 +/- 273 ml in Group PC versus 909 +/- 209 ml in Group WB; P < 0.001). Platelet count and collagen-induced whole blood platelet aggregation increased significantly higher in Group PC than Group WB after reinfusion. In conclusion, autologous fresh PC improved haemostasis compared with autologous fresh whole blood in cardiac reoperations with a low-dose aprotinin priming regimen.

[Anesthetic management of parturients with Marfan syndrome]

Ten pregnancies and 7 deliveries in 5 patients of Marfan syndrome were managed at our institution. Three patients were delivered with a cesarean section under general anesthesia, and one was delivered under epidural anesthesia. Three underwent vaginal delivery with epidural anesthesia. Two patients selected induced abortion, and one had a spontaneous abortion. Six of 7 neonates and all 5 mothers survived without any sequela. One had intrauterine fetal death due to dissection of aortic aneurysm. Simultaneous cesarean section and cardiovascular operation under cardiopulmonary bypass were performed in one case. In the parturient without progress of cardiovascular complication during pregnancy, painless labor under epidural anesthesia is our first choice to minimize hemodynamic derangement. Invasive arterial blood pressure and central venous pressure were monitored in all cases of vaginal delivery for tight hemodynamic control. Epidural anesthesia is also preferred in cases of elective cesarean section for obstetric indication. Emergency cesarean sections are performed in the cases of progressive dissection and urgent obstetric indication. General anesthesia was induced with fentanyl and midazolam to minimize cardiovascular response to tracheal intubation. We emphasize that evaluation of cardiovascular status and multidisciplinary approach are the key in the anesthetic management of parturients with Marfan syndrome.

Propofol as a continuous infusion during cardiopulmonary bypass does not affect changes in serum free fatty acids

Perioperative myocardial infarction or ischaemia is a potential consequence of cardiac surgery and elevated free fatty acids can increase the severity of myocardial ischaemic damage. We investigated perioperative changes in serum free fatty acids, and other serum lipids, as a consequence of using propofol infusions for cardiac surgery during cardiopulmonary bypass. Twenty-five patients undergoing elective coronary artery bypass grafting were allocated to two groups. One group of 12 patients was given a continuous infusion of propofol and the other group of nine patients received intermittent boluses of midazolam as a hypnotic agent. Serum lipid concentrations were measured at four periods perioperatively. Changes in free fatty acid concentrations were similar between the two groups. Lipid concentrations related to triglyceride in the propofol group decreased on one occasion but subsequently returned to control value. On the other hand, such values in the midazolam group remained lower than control values. Propofol is not a contraindication as an anaesthetic for cardiac surgery in respect of concern regarding the effects of free fatty acids.

Preservation of collagen-induced whole blood platelet aggregation by tranexamic acid therapy in primary cardiac valve surgery

Haemostatic disorder is one of the most common complications following cardiac surgery with cardiopulmonary bypass (CPB). Tranexamic acid reduces blood loss and allogeneic blood transfusion requirement in cardiac surgery. It had been thought that tranexamic acid inhibited fibrinolysis alone following CPB. In the present study, the haemostatic effects of tranexamic acid (20 mg/kg body weight bolus after induction of anaesthesia followed by continuous infusion at 2 mg/kg/h), including fibrinolysis and platelet function, were investigated in 22 patients (tranexamic acid group n = 12; control group n = 10) undergoing primary cardiac valve surgery. Fibrinolysis following CPB was reduced significantly in the tranexamic acid group. Following protamine administration, the reduction of collagen-induced whole blood platelet aggregation was mitigated significantly in the tranexamic acid group compared with the control group (36% reduction in the tranexamic acid group vs 58% in the control group; p = 0.011), although platelet counts did not differ between the two groups. In conclusion, tranexamic acid not only inhibits fibrinolysis directly, but also may preserve platelet function following CPB.

Cytogenetic studies of Hynobiidae (Urodela) XVI. Comparative C-banded karyotype analysis of Pseudohynobius flavomaculatus (Fei et Ye), Ranodon shihi (Liu) and Batrachuperus pinchonii (David)

Initial analysis of Pseudohynobius flavomaculatus chromosomes determined the chromosome number of this species to be 2n = 52. A re-examination of Ranodon shihi chromosomes detected 2n = 66 chromosomes, in contrast with a previous finding of 2n = 64. The C-banding patterns of these two species and that of Batrachuperus pinchonii were compared with each other. Regions of homoeology in the C-banding pattern among these three species represented 33.51-48.30% of the total length of their chromosomes. We also detected two types of chromosome rearrangement in hynobiid species based on the results of the present and previous cytogenetic studies.

An analysis of risk factors of perioperative bleeding in surgical repair of abdominal aortic aneurysm

BACKGROUND

In surgical repair of abdominal aortic aneurysm (AAA), excessive bleeding which causes postoperative complications is sometimes observed. To determine the risk factors of perioperative excessive blood loss, this retrospective study was performed.

METHODS

Design. A retrospective study. Setting. An academic medical center. Participants. One hundred and forty patients underwent elective surgical repair of an abdominal aortic aneurysm (AAA) at our institution from 1995 through 1997. Measurements. The present study includes critical review of 140 consecutive charts of patients undergoing elective surgical repair of AAA. Preoperative laboratory data, intraoperative data and amount of blood loss to identify risk factors of perioperative blood loss. Factors which were found to be significantly associated with the amount of perioperative blood loss were preoperative plasma fibrin degradation product (FDP) level (r=0.445), amount of immediate re-infusion of shed blood (r=0.438), and duration of operation (r=0.411).

RESULTS

Preoperative fibrinogen level correlated with perioperative blood loss little (r=-0.187). Preoperative platelet count or the other coagulation profile did not affect the amount of perioperative blood loss. The patients whose preoperative FDP were more than 40 microg x ml(-1) significantly increased the risk of excessive blood loss compared with less than 40 microg x ml(-1).

CONCLUSIONS

The significant preoperative risk factor of perioperative blood loss was only FDP level in present study. Especially, the patients whose preoperative FDP were more than 40 microg x ml(-1) increased the risk of excessive blood loss.

Hemostatic effects of low-dose protamine following cardiopulmonary bypass

Twenty-eight patients undergoing cardiac surgery were prospectively studied and were assigned to two groups. The patients received 0.8- (Group L) or 2.0-fold (Group H) dose of protamine for the neutralization after cardiopulmonary bypass (CPB) which was determined by Hepcon HMS(R) assay system in which the reagent chamber containing the concentration of protamine that completely neutralized the heparin had the shortest clotting time. Mean dose of protamine was 1.60 +/- 0.50 mg kg(-1) in Group L, and 3.56 +/- 1.48 mg kg(-1), respectively. Activated clotting times (ACT) were comparable between the two groups through this study period. In Group H, platelet counts significantly decreased to 69% of that before protamine administration, and plasma platelet factor 4 level significantly increased to approximate 2-fold of that before protamine administration just after protamine administration, respectively. However, these phenomena were not observed in Group L. In addition, these hemostatic changes occurred transiently just after protamine administration. We conclude that the low-dose protamine may prevent transient platelet depletion following CPB. Low-dose protamine can neutralize anticoagulation effect of heparin sufficiently and may mitigate protamine-induced platelet dysfunction.

[Anesthetic management of heart transplantation]

We anesthetized a 47-yr-old man with end-stage hypertrophic cardiomyopathy for heart transplantation. This is the first case of heart transplantation from a patient with brain death, since the organ transplantation law had become valid in Japan. Anesthesia was induced and maintained with fentanyl and diazepam. Aseptic technique was used in inserting and securing all catheters. The patient was assisted by left ventricular assist system, and hemodynamic suppression at anesthetic induction was trivial. Since complete AV block was present at the termination of cardiopulmonary bypass (CPB), VVI pacing and infusion of isoproterenol were started. In addition, nitroglycerin was given for pulmonary vasodilation. The cardiovascular support used for weaning from CPB included dobutamine, isoprote-renol, dopamine and milrinone. Following weaning from CPB sinus rhythm appeared spontaneously and function of the transplanted heart was satisfactory. When the patient was transported to ICU reduction in doses of catecholamines was possible, and dopamine and milrinone were infused. The patient was extubated 10 hours after admission to ICU.

[Intraoperative management of heart transplantation in Japan--report of two cases]

We experienced intraoperative anesthetic management of two cases of heart transplantation in Japan. Both patients were in the end stage of cardiac failure due to dilated cardiomyopathy. One patient had had implantation of left ventricular assist system, and another patient had had implantation of automated cardioveter defibrillator. Transesophageal echocardiography was useful for the monitoring of cardiac function during the operation. Anti-arrythmic therapy including heart pacing and protection of right heart failure are important for the circulatory management of heart transplantation. The anesthesiologist is needed not only for the management of respiration and circulation but also for the prevention of infection and control of the time schedule.

Cardiac transplantation under new legislation for organ transplantation in Japan: report of two cases

During the past 2 years since new legislation for organ transplantation from brain-dead donors came into effect in Japan, 3 cardiac transplants have been carried out, 2 of which were performed at the National Cardiovascular Center (NCVC). The recipient cases were 46- and 25-year-old male patients who suffered from end-stage dilated cardiomyopathy and had been listed for cardiac transplantation in the Japan Organ Transplantation Network as status I candidates. The first patient was supported by the use of a paracorporeal air-driven left ventricular assist device of the NCVC type, and had a moderate degree of renal and hepatic dysfunction at the time of transplantation. Donor hearts were transported from distant hospitals (Tokyo and Miyagi prefecture) and the transportation time was 1 h 33 min and 2h 4 min, respectively. The operation was performed by the standard technique (Lower-Shumway) in the first patient and by the bicaval anastomosis technique in the second patient. Reperfusion of the transplanted heart was performed retrogradely through the coronary sinus utilizing leukocyte-depleted blood with a gradual increase in temperature. Total ischemic time was 3 h 34 min and 3 h 35 min, respectively. Weaning from the cardiopulmonary bypass was easy and uneventful in each patient. Immunosuppressive therapy was conducted with OKT-3 induction in the first patient because of the coexisting renal dysfunction and with a triple immunosuppressive regimen for both patients. Routine endomyocardial biopsy showed acute rejection of less than grade Ib, and the patients were discharged on the 65th and 46th postoperative day, respectively. At present, both patients are in the NYHA class I state and are ready to return to work. The uneventful recovery seen in these patients shows the advances made in transplant medicine, including the progress and improvement of immunosuppressive therapy, surgical techniques, myocardial protection, and detection and treatment of infection. Further efforts are required to fully establish the cardiac transplantation program in Japan.

[Anesthetic management for carotid and coronary artery surgery--concomitant versus two stage operation]

We reviewed the anesthetic management of 16 patients with concomitant severe coronary and carotid artery diseases. Eight patients underwent concomitant operations of coronary artery bypass graft and carotid endarterectomy, while the other 8 patients underwent two stage operation. Candidates for concomitant operations had unstable angina or serious coronary disease such as three vessel disease or severe stenosis of LMT. In comparison, most of patients undergoing two stage operation had symptomatic or occlusive carotid disease. In all cases, anesthesia was maintained with fentanyl and midazolam and the perfusion pressure during cardiopulmonary bypass was maintained above 70 mmHg. Some patients received thiopental or propofol for brain protection. The concomitant operations required much more transfusion and longer operation time than two stage operation. In addition, several cases of the concomitant operation needed intra-aortic balloon pumping or high dose of catecholamines. Indications for concomitant operation or two stage operation have to be determined through discussion among anesthesiologist, neurovascular as well as cardiovascular surgeons.

[Anesthetic management of patients undergoing implantation of left ventricular assist system]

We examined the anesthetic management of six patients with end-stage dilated and hypertrophic cardiomyopathy for implantation of left ventricular assist system. Although anesthesia was induced only with fentanyl or with combination of fentanyl and diazepam, hemodynamic changes after the anesthetic induction were variable and preoperative evaluation of left ventricular ejection fraction did not predict the hemodynamic changes. After the weaning from cardiopulmonary bypass, the right ventricular support by catecholamines, such as dopamine and dobutamine, and phosphodiesterase III inhibitors, such as amrinone, and pulmonary vasodilation by inhalation of nitric oxide were useful to maintain volume loading to the left ventricular assist system.

[Anesthetic management for implantation of implantable cardioverter-defibrillators]

Implantable cardioverter-defibrillators (ICDs) were implanted in 44 patients at the authors' institution. The anesthetic management was reviewed retrospectively. Ten of the 44 patients received the third generation ICD devices, while the rest received the fourth generation devices. For thirteen patients receiving the fourth generation devices, implantation was performed under local anesthesia with monitored care of anesthesiologists. Propofol was infused to achieve deep sedation during induced ventricular fibrillation and later cardioversion for testing the devices. Implantation was performed under general anesthesia with combination of fentanyl and volatile anesthetics for the remaining 31 patients. Patients who received ICDs under local anesthesia had significantly greater values of ejection fraction in preoperative examination than values in patients who received ICDs under general anesthesia. Operation time of the implantation under local anesthesia was significantly shorter than that under general anesthesia. Though infusion of propofol produced a moderate decrease of blood pressure in patients who received ICDs under local anesthesia, no patient showed major complication. Local anesthesia with sedation with propofol can be an option in anesthetic management for implantation of an ICD if an anesthesiologist cares the patient whose cardiac function is not compromised.

Study on the effectiveness of toborinone (OPC-18790) in the treatment of heart failure in patients following cardiac surgery

Toborinone ((+/-)-6-[3-(3,4-dimethoxybenzylamino)-2-hydroxypropoxy]-2(1H)-qui nolinone, CAS 128667-95-8, OPC-18790), a novel cardiotonic agent with an inhibitory action on phosphodiesterase, is known to have a potent positive inotropic action with no positive chronotropic effect. The effectiveness of this drug in the treatment of heart failure occurring immediately after extracorporeal circulation (ECC) in cardiac surgery was investigated. The study was conducted in 12 patients with valvular heart disease showing a cardiac index (CI) of below 2.8 l/min/m2 and/or pulmonary capillary wedge pressure (PCWP) or pulmonary arterial diastolic pressure (PAD) of above 8 mmHg immediately after extracorporeal circulation. In group A (n = 6), toborinone was infused at a rate of 40 micrograms/kg/min for the first 5 min and then at 10 micrograms/kg/min for 85 min. In group B (n = 6), the drug was infused at a rate of 10 micrograms/kg/min for the entire 90 min. CI, mean systemic arterial pressure (mSAP), mean pulmonary artery pressure (mPAP), CVP, PCWP, and heart rate were measured at 5, 15, 30, 60, and 90 min after the start of infusion. The infusion volume required to maintain a constant PCWP was also estimated. In group A, CI increased rapidly and significantly from the baseline of 2.48 +/- 0.23 l/min/m2 to 3.57 +/- 1.07 l/min/m2 at 5 min after the start of infusion, and at that time mSAP was slightly decreased. In group B, CI increased gradually from the baseline of 2.53 +/- 0.18 l/min/m2 to 3.08 +/- 0.34 l/min/m2 at 15 min after the start of infusion, but almost no change was seen in mSAP. During the first 30 min, group A required a significantly larger infusion volume (983 +/- 395 ml) than group B (475 +/- 184 ml). From 30 to 90 min after the start of infusion, CI remained increased to similar levels in both groups and mSAP levels were also similar. There were no significant differences between the two groups in any other parameter. Continuous infusion of toborinone appears to be effective for treating heart failure occurring immediately after ECC in cardiac surgery. Initial loading at a rate of 40 micrograms/kg/min rapidly increased CI but was accompanied by mild hypotension. Constant infusion at 10 micrograms/kg/min brought about a more gradual effect that was similar to that of loading at 40 micrograms/kg/min, but without inducing hypotension. Thus, infusion at 10 micrograms/kg/min is considered preferable in order to avoid a larger-than-necessary infusion volume.

Retrospective analysis of effect of low-dose aprotinin priming on allogeneic blood transfusion in repeated cardiac operations

The objective of this retrospective study was to investigate efficacy of low-dose aprotinin priming therapy on the requirement of allogeneic transfusion and to identify risk factors for allogeneic transfusion in patients undergoing repeated cardiac operations. The present study includes a critical review of 124 consecutive charts of patients undergoing elective repeat cardiac surgery. We examined the effect of low-dose aprotinin priming therapy on blood loss, amounts of mediastinal drainage following intensive care unit (ICU) administration and the number of units of blood products given during the perioperative period. The rate of nonallogeneic transfusion was not affected by low-dose aprotinin priming therapy, although aprotinin reduced the amount of allogeneic transfusion and the amount of mediastinal drainage 12 h following ICU admission. In conclusion, low-dose aprotinin priming therapy is effective in reducing blood loss and the amount of allogeneic transfusion. However, it failed to improve the rate of cardiac reoperations without allogeneic blood transfusion.

Cerebral production of adrenomedullin afer hypothermic cardiopulmonary bypass in adult cardiac surgical patients

Adrenomedullin is a potent vasodilatory peptide originally identified in human pheochromocytoma. Plasma adrenomedullin increases during and after cardiopulmonary bypass (CPB). However, the site at which production of adrenomedullin is augmented has not been identified. In the present study, we examined the contribution of the cerebral vasculature to the production of adrenomedullin in patients before, during, and after CPB. Ten patients undergoing coronary artery bypass grafting with mild hypothermic CPB were studied. Cerebral blood flow was measured using the Kety-Schmidt method before, during, and after CPB. Plasma adrenomedullin concentrations from radial artery and internal jugular bulb blood were measured by radioimmunoassay, and cerebral adrenomedullin production was evaluated. Adrenomedullin production in the cerebral vasculature was significantly enhanced after CPB and correlated with aortic cross-clamping time. The cerebral adrenomedullin production may contribute to the increased plasma level of adrenomedullin after CPB.

IMPLICATIONS

Plasma adrenomedullin has been reported to increase in humans after cardiac surgery involving cardiopulmonary bypass. In this study, we demonstrated that cerebral adrenomedullin production may contribute to the increased plasma level of adrenomedullin after cardiopulmonary bypass.

Effect of prostaglandin E1 and nitroglycerin on portal venous flow during hypothermic extracorporeal circulation: assessment by transesophageal echography

BACKGROUND

Although several vasodilators are used to control vascular resistance during cardiac surgery, their effects on splanchnic circulation during extracorporeal circulation are unknown. We designed the present noninvasive study to evaluate the effect of prostaglandin E1 and nitroglycerin on portal venous flow during extracorporeal circulation using transesophageal echography.

METHODS

We included 26 patients undergoing cardiac surgery with moderate hypothermic extracorporeal circulation in this study. After obtaining hemodynamic stability under extracorporeal circulation, we measured portal venous diameter, mean flow velocity and the velocity time integral using transesophageal echography and calculated portal venous flow. The patients were assigned to two groups where either prostaglandin E1 (N = 13) or nitroglycerin (N = 13) was administered intravenously to maintain perfusion pressure at the level of 70 mmHg. We measured the same parameters 20 and 40 min following administration of the drug.

RESULTS

Visualization of the portal vein was obtained by transesophageal echography in anesthetized patients. Calculated portal venous flow significantly increased in the prostaglandin E1 group, while it did not alter in the nitroglycerin group.

CONCLUSION

The present results indicate that transesophageal echography may be a feasible tool to assess portal venous flow, and that prostaglandin E1 may improve the blood distribution to the splanchnic area and the liver during hypothermic extracorporeal circulation.

[Anesthetic management of left ventricular reduction surgery (Batista procedure)]

We experienced anesthetic management of left ventricular reduction surgery (Batista procedure) which is a newly developed procedure for treating end-stage dilated cardiomyopathy. The patient was a 41-year-old man who had been suffering from cardiac failure and refractory ventricular tachycardia. The anesthesia was induced and maintained with meticulous administration of fentanyl. After resection of the left ventricular free-wall, the left ventricular diastolic diameter decreased to 46 mm, from 79 mm of preoperative measurement. Weaning from cardiopulmonary bypass was successful with the use of catecholamines and intra-aortic balloon pumping. Administration of both vasodilators and phosphodiesterase inhibitors such as milrinone also contributed to reducing afterload and maintaining cardiac output. In addition to standard hemodynamic monitoring, transesophageal echocardiography provided invaluable information on determining cardiac dimensions and evaluating left ventricular wall motion.

Effects of thiopental, ketamine, etomidate, propofol and midazolam on the production of adrenomedullin and endothelin-1 in vascular smooth muscle cells

Endothelin-1 (ET-1) and adrenomedullin (AM) are potent vasoconstrictive and vasodilative peptides. Vascular smooth muscle cells are one of the major producing tissues of these peptides. We investigated effect of thiopental, ketamine, etomidate, midazolam and propofol on the production of ET-1 and AM in cultured rat aorta vascular smooth muscle cells. Rat cultured vascular smooth muscle cells are used and the dose-dependent effect (10(-8)-10(-4) M) of thiopental, ketamine, etomidate, midazolam, and propofol on the production of ET-1 and AM was examined. The concentration of these peptides in the culture medium were measured by radioimmunoassay. Ketamine, etomidate, propofol and midazolam, but not thiopental, decreased the production of ET-1 at a concentration of 10(-4) M and the effect of midazolam is the most potent. Thiopental and etomidate produced small but significant increases in the production of AM at a concentration of 10(-4) M. Ketamine did not affect the production, but propofol and midazolam decreased the production at 10(-4) M and 10(-5) M, respectively. These results suggest that thiopental, ketamine, etomidate, propofol and midazolam differentially affect the production of ET-1 and AM in rat vascular smooth muscle cells.

Evaluation of platelet function by Sonoclot analysis compared with other hemostatic variables in cardiac surgery

Platelet function can be easily measured as time to peak (TP) by Sonoclot Coagulation & Platelet Function Analyzer (Sienco Inc., Morrison, CO) analysis. However a correlation between Sonoclot analysis and platelet aggregation, which is accepted as a test of platelet function, has not been established. In this study, we compared TP and collagen-induced whole blood platelet aggregation in 15 patients undergoing cardiac surgery. Two or three blood samples were randomly obtained from each patient before and after cardiopulmonary bypass (CPB). Sonoclot analysis, collagen-induced whole blood aggregation, and laboratory measurement (including platelet count and coagulation profile) were measured. Seventy-two samples were obtained (35 before CPB and 37 after CPB). TP was correlated with collagen-induced whole blood aggregation (r = -0.652), platelet count (r = -0.671), fibrinogen level (r = -0.598), prothrombin time (r = 0.394), activated partial thromboplastin time (r = 0.486), and use of CPB (r = 0.380). Significant predictors of TP for multiple linear regression modeling were collagen-induced whole blood aggregation, platelet count, and fibrinogen level (r = 0.742). In conclusion, Sonoclot analysis TP predicts approximate platelet function in patients undergoing cardiac surgery.

IMPLICATIONS

Approximate platelet function can be easily measured as time to peak by Sonoclot analysis. In this study, time to peak was predicted by platelet count, whole blood platelet aggregation, and fibrinogen level for multiple linear regression modeling.

[Effects of changes in head and neck position on a tracheal tube cuff]

Thirteen patients were intubated with cuffed reinforced spiral tracheal tubes. Intracuff pressure and volume were measured as the position of the head and neck was altered. No significant changes in intracuff pressure and volume were observed with lateral rotation of the head. A significant increase in intracuff pressure was observed and excessive pressure (> 25 cm H2O) developed in 8 patients with head and neck flexion. A significant decrease of intracuff pressure and air-leak were observed in 9 patients with extension. Reinflated intracuff volume decreased and reinflated intracuff pressure increased significantly, and residual excessive pressure was observed in 4 patients with flexion. Both reinflated intracuff volume and pressure increased significantly, and excessive pressure was observed in 8 patients and residual air-leak developed in a patient in spite of excessive pressure with extension. The authors speculate that endotracheal tube movement by changes in head and neck position has effects on intracuff pressure and volume.

Incidence of venous and paradoxical air embolism in neurosurgical patients in the sitting position: detection by transesophageal echocardiography

BACKGROUND

Venous air embolism (VAE) and paradoxical air embolism (PAE) are serious complications associated with the sitting position for neurosurgery. Although PAE is the result of VAE, the incidence of PAE according to the severity of VAE has not been investigated systematically in humans.

METHODS

Twenty-one patients scheduled for neurosurgery in the sitting position were investigated prospectively. VAE and PAE were continuously monitored by cardiac two-dimensional 4-chamber view using transesophageal echocardiography (TEE) and the severity of VAE and PAE was quantitatively graded from 0 to 3 by the microbubbles score. Haemodynamic parameters and end-tidal CO2 concentration (PETCO2) during VAE and PAE were also recorded.

RESULTS

Microbubbles in the right atrium appeared in all patients and the number of patients involved in grades 0, 1, 2 and 3 of VAE was 0, 10, 3 and 8, respectively. PAE occurred in 3 patients and only followed grade 3 of VAE. PAE always appeared from 20 to 30 s after the most severe VAE. A reduction of PETCO2 and an increase of pulmonary artery pressure were noted during all episodes of grades 2 and 3 VAE. In contrast, a significant reduction of systemic blood pressure occurred in 1 case of grade 2 and 3 cases of grade 3.

CONCLUSIONS

VAE detected by TEE appeared in all patients undergoing neurosurgery in the sitting position and PAE only occurred following the most severe grade of VAE. To prevent growth of VAE is an important prophylactic for PAE.

[Anesthetic management for Fontan procedure without the use of cardiopulmonary bypass]

We examined the anesthetic management for Fontan procedure performed without the use of cardiopulmonary bypass (Group N, n = 7) and that for equivalent procedure under cardiopulmonary bypass (Group E, n = 10) retrospectively. In Group N, surgical repairs of major vascular system were performed while bypassing the superior or inferior vena cava to the right atrium. The use of anesthetics and vasoactive agents was similar in both groups. Patients in Group N had significantly less blood loss and were extubated significantly earlier than those in Group E. However, significant metabolic acidosis was noted in Group N when reconstruction of the vascular system was completed and so-called Fontan circulation was initiated. Fontan procedure without the use of cardiopulmonary bypass may have advantage of less impairment for the cardiac performance and the pulmonary vasculature. However, its anesthetic management is another challenge to the anesthesiologist and requires meticulous control of both optimum preload and vascular resistance of the pulmonary artery.

Incidence of venous and paradoxical air embolism in neurosurgical patients in the sitting position: detection by transesophageal echocardiography

BACKGROUND

Venous air embolism (VAE) and paradoxical air embolism (PAE) are serious complications associated with the sitting position for neurosurgery. Although PAE is the result of VAE, the incidence of PAE according to the severity of VAE has not been investigated systematically in humans.

METHODS

Twenty-one patients scheduled for neurosurgery in the sitting position were investigated prospectively. VAE and PAE were continuously monitored by cardiac two-dimensional 4-chamber view using transesophageal echocardiography (TEE) and the severity of VAE and PAE was quantitatively graded from 0 to 3 by the microbubbles score. Haemodynamic parameters and end-tidal CO2 concentration (PETCO2) during VAE and PAE were also recorded.

RESULTS

Microbubbles in the right atrium appeared in all patients and the number of patients involved in grades 0, 1, 2 and 3 of VAE was 0, 10, 3 and 8, respectively. PAE occurred in 3 patients and only followed grade 3 of VAE. PAE always appeared from 20 to 30 s after the most severe VAE. A reduction of PETCO2 and an increase of pulmonary artery pressure were noted during all episodes of grades 2 and 3 VAE. In contrast, a significant reduction of systemic blood pressure occurred in 1 case of grade 2 and 3 cases of grade 3.

CONCLUSIONS

VAE detected by TEE appeared in all patients undergoing neurosurgery in the sitting position and PAE only occurred following the most severe grade of VAE. To prevent growth of VAE is an important prophylactic for PAE.

Increased plasma adrenomedullin concentrations during cardiac surgery

1. Adrenomedullin (AM), a potent hypotensive peptide, was originally isolated from human phaeochromocytoma. Plasma AM concentrations are elevated in hypertension, heart failure and renal failure in proportion to the severity of the disease. This study was performed to investigate the pathophysiological significance of AM during cardiac surgery. 2. Serial blood samples were obtained from patients undergoing cardiac surgery and plasma AM concentrations were determined by specific radioimmunoassay. 3. Plasma AM concentrations did not increase with anaesthesia or surgery (n = 9). Plasma AM concentrations gradually increased during cardiopulmonary bypass and after pulmonary reperfusion. After pulmonary reperfusion, plasma AM concentrations increased further. In addition, we measured plasma AM concentrations in the pulmonary vein (n = 8) and coronary sinus (n = 8) to examine the contribution of the lungs and heart to the increase in circulating AM concentrations after cardiopulmonary bypass. However, no significant differences were seen in plasma AM concentrations of the pulmonary vein or the coronary sinus and the aorta. Peak AM concentrations during cardiac surgery correlated with duration of surgery. Elevated plasma AM levels during and after surgery began to decline next day after surgery and returned to normal levels 7 days after surgery. 4. These results demonstrate that plasma AM concentrations increase during cardiac surgery and that the duration of surgery may be related to the changes in AM concentrations. Taken together with recent findings that vascular endothelial cells and vascular smooth muscle cells actively produce AM, these results suggest that plasma AM during cardiac surgery may act as a vasodilatory hormone.

[Early recovery after valvular heart surgery]

There have been published not a few reports concerning the early recovery from heart surgery. But most of them were restricted in CABG cases. We report our efforts and its results about the early recovery from valvular heart surgery. To make a contribution to the early recovery we have made some efforts since 1995, including normothermic perfusion, low-dose fentanyl and introduction of terminal warm blood cardioplegia. As the results, the tracheal intubation period was shortened from 12.6 +/- 5.3 (hour) to 6.7 +/- 4.1. The number of the cases who had tracheal extubation in the operative day increased from 27% to 84%. The postoperative cardiac function was satisfactory and there were no abdominal or neurologic disturbances among the patients those who were entered into the early recovery protocol. We obtained satisfied early recovery in safe after valvular heart surgery.

[A successful perioperative anticoagulation therapy and monitoring of a patient with hereditary plasminogen abnormality undergoing aortic valve replacement]

During perioperative period, plasminogen abnormality can result in unusual or unexplained clotting that occurs spontaneously or after minor trauma. However, there has been no report on perioperative anticoagulation therapy and monitoring in patients with hereditary plasminogen abnormality undergoing cardiac surgery. We performed a successful perioperative anticoagulation therapy and monitoring of a patient with hereditary plasminogen abnormality undergoing cardiac surgery. A 48-year-old male patient with severe aortic valve stenosis, who had had no episode of thrombosis, was scheduled for aortic valve replacement Preoperative laboratory screenings detected his abnormal plasminogen activity (7.6% normal), and he was diagnosed as hereditary plasminogen abnormality. Anesthetic course was uneventful until the initiation of cardiopulmonary bypass (CPB). During CPB, heparin level was monitored every 30 minutes by Hepcon/HMS (Medtronic Hemotec, Parker, CO). No thrombus was observed in the CPB circuit. Plasminogen activity, fibrin degradation products (FDP) and D-dimer were not elevated during perioperative period. Protamine dosage was determined by protamine titration method, and protamine was administrated after the termination of CPB. No major bleeding was observed after protamine administration. When the patient was admitted to ICU, anticoagulation therapy was started immediately. During perioperative period, no episode suggesting thrombosis was observed. In conclusion, we consider that this successful anticoagulation therapy and monitoring during CPB has been achieved by use of Hepcon/HMS.

[Regional cerebral hypoperfusion reduces the effect of rectal midazolam in children with Moyamoya disease]

To investigate the effect of regional cerebral blood flow on the effect of midazolam, we evaluated 99mTc-hexamethylpropylene-amine-oxime-single photon emission computed tomography (SPECT) in 37 cases of childhood moyamoya disease. They were divided into two groups according to the findings of SPECT; one group showed hypoperfusion in the bifrontal regions (n = 20), and the other did not (n = 17). Both groups received 1 mg.kg-1 of midazolam transrectally 30 min before the anesthesia induction and level of sedation was measured with six point scales. Significantly lower level of sedation score was recognized in the group that showed hypoperfusion in bifrontal regions (P < 0.05). Our finding may suggest that regional cerebral hypoperfusion may modify the sedative effect of midazolam in children with moyamoya disease.

Resection of a large, high-flow arteriovenous malformation during hypotension and hypothermia induced by a percutaneous cardiopulmonary support system. Case report

The key to successful surgical resection of cerebral arteriovenous malformations (AVMs) is control of bleeding and cerebral swelling. Induced hypotension is one of the most valuable means of achieving this control. The authors introduced induced hypotension with mild hypothermia by using a percutaneous cardiopulmonary support system (PCPS) to resect a large, high-flow AVM. The efficacy and technical points of this method are discussed. The PCPS, whose entire intraluminal surface was coated with heparin, was established through a transfemoral route. During resection of the AVM, a mean arterial blood pressure of 60 mm Hg and a mean body temperature of 30 degrees C were easily maintained by regulating the flow rate of the PCPS and by blood cooling. The activated coagulation time was maintained at approximately 250 seconds with a minimum systemic administration of heparin. The authors report the case of a 30-year-old woman who presented with intraventricular hemorrhage and was diagnosed as having a large, high-flow AVM located in the left sylvian fissure. The AVM was fed by the left middle, posterior, and anterior cerebral arteries and drained by the many cortical ascending veins and the basal vein. The patient underwent surgery after hypotension and hypothermia had been induced via the PCPS method. Induced hypotension decreased the tension of the nidus and made its dissection easier. The AVM was totally resected and no hemostatic difficulties were encountered. On the basis of the authors' experience, they suggest that hypotension and hypothermia induced by using the PCPS is a powerful tool for the successful resection of large, high-flow AVMs.

[A case of twice catastrophic pulmonary vasoconstriction-type shock induced with protamine sulfate]

A 71-year-old female was scheduled for the re-replacement of a mechanical mitral valve. After the cardiopulmonary bypass (CPB) she was administered protamine sulfate. Subsequently mean systemic blood pressure went down below 20 mmHg and central venous pressure and mean pulmonary blood pressure were above 50 mmHg, and immediately CPB was restarted as an assist device for circulation. After the second CPB, she was administered protamine sulfate again, and the same shock occurred. At last the third CPB was restarted and the third protamine administration was not undertaken after the third CPB. Although her postoperative drainage may have been relatively much more compared with cases of neutralization of heparin, postoperative course was uneventful in this patient. Administered protamine to neutralize the anticoagulat effects of heparin may often cause temporary treatable hypotension. Although protamine may rarely cause severe pulmonary vasocontriction and anaphylactoid reactions, clinical pictures become critical once these reactions occur. It is important in these cases to identify protamine as the cause of shock and avoid repeating the shocks.

A guide to preventing deep insertion of the cannulation needle during catheterization of the internal jugular vein

OBJECTIVE

Accidental puncture of the vertebral artery during the internal jugular vein cannulation produces lethal sequelae. To prevent this, the cannulation needle must not be inserted too deeply. However, there is no useful guide for the optimal length of insertion of the needle for accessing the internal jugular vein. The authors examined the length of the needle needed to reach the internal jugular vein with three different sizes of needle (16, 20, and 23 gauge).

DESIGN

Prospective study.

SETTING

An academic medical center.

PARTICIPANTS

Patients undergoing cardiovascular surgeries.

INTERVENTIONS

The cannulation of the internal jugular vein was performed through the right internal jugular vein by the high approach. The needle was slowly advanced, keeping constant negative pressure on the syringe at 45 degrees to the skin surface until blood was aspirated; if blood was not aspirated during insertion, the needle was slowly withdrawn until blood was aspirated. The distance to the internal jugular vein was assessed by calculating the entire length of needle minus the length of needle from the skin surface to the hub.

MEASUREMENTS AND MAIN RESULTS

The mean distance to the internal jugular vein ranged from 15.0 to 21.5 mm, and the larger needle required the longer distance to the internal jugular vein.

CONCLUSIONS

The results may be a useful guide to prevent too deep insertion of the needle during internal jugular vein catheterization, especially when teaching residents who have limited experience with internal jugular vein catheterization.

[Anesthesia for pediatric open heart surgery without transfusion]

We reviewed 50 recent anesthetic managements of pediatric patients for open heart surgery weighing between 6.5 to 12 kg to evaluate factors contributing to successful management without transfusion. Twenty six cases were managed without transfusion, whereas nine cases required less than 30 ml.kg-1 of transfusion and the other 15 cases needed massive transfusion amounting to more than 50 ml.kg-1. The followings are important factors to complete the open surgery without transfusion; 1) the patient's weight is 9 kg or more, 2) the duration of cardiopulmonary bypass is less than 120 minutes, and 3) intraoperative bleeding is less than 10 ml.kg-1. We could find several advantages in patients without transfusion, compared with those receiving transfusion, such as greater urine output, less bleeding during the surgery, more concentrated platelet and better respiratory condition after the surgery. In addition, the lager the amount of transfusion we observed the more disadvantageous to the patients. Even if transfusion can not be avoided, minimal transfusion of the washed red cell is favorable.

[Brain monitoring with near infrared spectroscopy during carotid endarterectomy]

We evaluated clinical efficacy of near infrared spectroscopy (NIR) as a monitoring system for cerebral oxygenation during anesthesia for carotid artery endarterectomy. NIR proved to be affected significantly by clamping of the external carotid artery. The present study suggests that this monitoring system may be useful for evaluation of cerebral blood flow following declamping of the internal carotid artery, although it has some limitations during clamping of the artery.

[Cardiac surgery using cardiopulmonary bypass in a patient with sickle-cell trait]

The sickle-cell gene is most concentrated in West Central Africa, the northeast corner of Saudi Arabia and East Central India. Sickle cell trait is the heterozygous condition for Hb S gene. Thirty to fifty per cent of their hemoglobin is Hb S and the remainder is Hb A. The sickle-cell crisis is induced by hypoxia, hypercarbia, acidosis, low flow condition, and hypothermia, which leads to vasoocclusion. A 39-year-old black man from Burkina Faso located in West Africa with left ventricular rupture was admitted for operation using cardiopulmonary bypass (CPB). He had been diagnosed as sickle-cell trait. The Hb S concentration was 36.2 per cent before operation with hemoglobin electrophoresis. During CPB, the minimum blood temperature was 31 degrees C and an aortic cross-clamp was not done. Total CPB time was 1 hour 31 minutes. Use of vasodilator and hyperventilation was effective. No neurological sequelae were observed.

[Aortic dissection after weaning from extracorporeal circulation]

Acute aortic dissection is a rare complication of cardiac surgery. But once it happens, its outcome is often miserable. We experienced this complication after discontinuing cardiopulmonary bypass (CPB). A 56-year old man with mitral regurgitation was referred for mitral valve replacement under CPB. After weaning from extracorporeal circulation (ECC), the right radial artery pressure decreased suddenly and its waveform became flat. After 5 minutes, dissection of the ascending aorta was diagnosed by transesophageal echocardiography (TEE). We started to prevent ischemic brain damage immediately, but a severe brain damage occurred. Its early diagnosis is necessary and the prevention of critical brain damage due to low perfusion of the blood is important for anesthetic management.

[The efficacy of transesophageal echocardiography during the pericardial drainage of the cardiac tamponade after cardiac surgery]

For two cases of cardiac tamponade following cardiac surgery, the approaches for pericardial drainage were determined by the transesophageal echocardiography under general anesthesia. In most cases of cardiac tamponade after cardiac surgery the pericardial effusion is regional and localized due to adhesions of pericardium. Therefore subxiphoid incision approach of pericardial drainage cannot often be accomplished. In these cases transesophageal echocardiography can image the presence, location and size of the pericardial effusion and is an available method to determine the approach of pericardial drainage.

[Comparison of cerebral oxygen metabolism during normothermic versus moderate hypothermic cardiopulmonary bypass]

We compared the effects of normothermic (NCPB, N = 5) and moderate hypothermic (HCPB, (N = 5) cardiopulmonary bypass on cerebral oxygen metabolism in patients undergoing coronary artery bypass grafting. For monitoring of cerebral oxygenation, we used jugular venous oxyhemoglobin saturation (SjVO2) and near infrared spectroscopy (NIR). In NCPB group, although SjVO2 decreased temporally at the start of cardiopulmonary bypass, it became stabilized above 50% during the rest of cardiopulmonary bypass. In HCPB group, on the contrary, oxyhemoglobin measured by NIR showed maximum decrease during rewarming under cardiopulmonary bypass. Furthermore, SjVO2 decreased under 50% at the end of cardiopulmonary bypass (3/5 cases). We consider that NCPB is a useful technique for preventing cerebral hypoxia, if the decrease of SjVO2 during the early period of cardiopulmonary bypass is avoidable. Lastly, we also advocate that both SjVO2 and NIR are useful monitoring systems for continuous evaluation of cerebral oxygen metabolism during cardiopulmonary bypass.

[Anesthetic management for AICD (automatic implantable cardioverter defibrillator) implant surgery]

We studied anesthetic management and monitoring during AICD (automatic implantable cardioverter defibrillator) implantation. For anesthetic management, complete sedation and amnesia are needed during implantation procedures with rapid awakening and extubation after the surgery. We chose inhalation anesthesia supplemented with small doses of fentanyl or thiamylal. Monitoring for AICD implantation should be less invasive, continuous and rapid in responsiveness. For brain and cardiac monitoring, a combination of near infrared spectroscopy and transesophageal echocardiography was quite useful.

[Relationship between retained microbubbles and neuropsychologic alterations after cardiac operation]

We studied the relationship between quantity of microbubble retained in the left heart and neuropsychologic alterations after surgery in 21 patients undergoing cardiac surgery including cardiopulmonary bypass. The neuropsychologic change was evaluated by three kinds of psychological test, which mainly analyzed memory and cognition. The microbubble was continuously monitored by the long axis view of the descending aorta of transesophageal echocardiography and then quantitatively analyzed and graded by the on-line computer. More microbubbles were detected in the valve surgery requiring the intracardiac procedure than in coronary artery bypass grafting and neuropsychologic deterioration, although the relationship did not reach statistical significance. Since most of the microbubbles were detected during the unclamping of aorta and the weaning from cardiopulmonary bypass, a technical improvement of the surgical procedures could reduce them. We think that transesophageal echocardiography is useful for monitoring microbubbles during operation.

[Usefulness of monitoring with near infrared spectroscopy during retrograde cerebral perfusion]

Recently retrograde cerebral perfusion (RCP), a newly developed technique for cerebral protection during surgical replacement for thoracic aortic aneurysm, has been used in many institutes. However, there is no established monitoring methods for cerebral oxygenation during this procedure. In the present study, we examined if near infrared spectroscopy (NIR) is useful for monitoring cerebral oxygenation during RCP. We studied 7 patients undergoing operations for aneurysms of the ascending aorta and transverse arch in the supine position (Group A) and another seven patients undergoing operations for aneurysms of the transverse arch and descending aorta in the lateral decubitus position (Group D) in this study and monitored cerebral oxygenation with NIR. NIR showed a slow but continuous decrease in oxygenated hemoglobin and an increase in deoxygenated hemoglobin during RCP, while these changes disappeared following the termination of RCP. The degree of these changes in Group D was significantly greater than that in Group A. In comparison, we observed rapid reduction of oxygenated hemoglobin during the period of circulatory arrest and low perfusion pressure with NIR, suggesting the usefulness of RCP for cerebral oxygenation. NIR may be a useful method of monitoring cerebral oxygenation during RCP.

Optimal placement of CVP catheter in paediatric cardiac patients

For correct monitoring of central venous pressure (CVP) the tip of the CVP catheter should be placed in the superior vena cava (SVC). Since there is no useful guide for the optimal depth of insertion of CVP catheter in children undergoing cardiovascular surgery, we examined the relationship between the depth of the CVP catheter and easily measured body-size variables, such as age, weight and height, and then created a guide for the optimal placement of the paediatric population. The CVP catheterization was performed through the right internal jugular vein by the high approach. The position of the catheter tip was determined by the wave form of the CVP tracing and the depth of insertion was assessed by the external marking on the catheter at the cannulation site. The position of the catheter tip, determined by postoperative AP chest x-ray, was identified by the level of thoracic vertebra (T) corresponding to the position of the catheter tip. We analyzed the relationship between the depth of the catheter and patient's age, weight and height by linear regression analysis. The position of tip was normally distributed from T1 to T7 and the tips were centralized at levels of T3, T4 and T5 which anatomically correspond to SVC. The r values between the catheter depth and the three factors at each level were comparable, although the correlation between the depth of catheter and height was best. A simple guide for placement of the catheter tip at T3, T4 and T5 levels as a function of patient's height was created.(ABSTRACT TRUNCATED AT 250 WORDS)

[Anesthetic management using percutaneous cardiopulmonary support for cesarean section in a patient with severe pulmonary hypertension]

A 27-year-old female with severe pulmonary hypertension was scheduled to undergo an elective cesarean section at the 32-week gestational age. Since the preoperative assessment revealed that the patient could not tolerate the hemodynamic changes during the operation under general anesthesia without any cardiopulmonary support, the percutaneous cardiopulmonary support (PCPS) with a centrifugal pump was applied for the anesthetic management of the patient during the operation. After the induction of anesthesia, percutaneous cannulation was performed via the femoral artery and vein, and the PCPS was started with an assisted flow ranged 1.5-2.0 l.min-1. Then, the operation was performed, during which the cardiopulmonary function of the patient was well maintained with the aid of the PCPS. The operation was finished uneventfully, and the patient could successfully emerge from the PCPS immediately after the operation. The PCPS is thought to be very useful for the anesthetic management of the patients with poor cardiopulmonary tolerance.