OBJECTIVESTo compare the effects of lactated Ringer's solution (LR), 6% hetastarch in a balanced-saline vehicle (HS-BS), and 6% hetastarch in normal saline (HS-NS) on coagulation using thromboelastography.DESIGNProspective, randomized double-blinded evaluation of previously published clinical trial.SETTINGTertiary-care medical center.PARTICIPANTSPatients undergoing elective noncardiac surgery with an anticipated blood loss >500 mL. A total of 90 patients were enrolled with 30 patients in each group.INTERVENTIONSPatients received a standardized anesthetic. LR, HS-BS, and HS-NS were administered intraoperatively based on a fluid administration algorithm. Hemodynamic targets included maintenance of arterial blood pressure, heart rate, and urine output within a predefined range.MEASUREMENTS AND MAIN RESULTSThromboelastography variables for r time, k time, maximum amplitude, and alpha angle (mean +/- SD) were recorded at induction of anesthesia, at the end of surgery, and 24 hours postoperatively. Patients in the LR group showed a state of hypercoagulation at the end of surgery with reductions (p < 0.005) in r time (-3.8 +/- 6.7 mm) and k time (-1.7 +/- 2.5 mm). This state of hypercoagulation continued into the postoperative period. Patients in the HS-NS group showed a state of hypocoagulation with increases (p < 0.05) in r time (+6.2 +/- 8.5 mm) and k time (+1.7 +/- 3.9 mm) and a reduction in maximum amplitude (-8.0 +/- 9.8 mm) at the end of surgery. This state of hypocoagulation was reduced in the postoperative period. Patients in the HS-BS group showed no significant changes in coagulation status at end of surgery, with the smallest changes in r time (-0.3 +/- 4.1 mm), k time (+0.1 +/- 3.1 mm), maximum amplitude (-5.4 +/- 12.3 mm), and alpha angle (0.3 +/- 12.5 degrees ).CONCLUSIONLR-treated patients exhibited a hypercoagulative profile that persisted into the postoperative period. HS-BS administration was associated with a lesser change in the coagulation profile compared with HS-NS, which was associated with a hypocoagulative state.

S179 INTRODUCTION: Intraoperative hypovolemia is common and is associated with an increased postoperative morbidity and prolonged hospital stay [1]. Esophageal Doppler (EDM Deltex Med Inc., Irving, Texas) allows non-invasive continuous monitoring of stroke volume (SV) and calculated cardiac output (CO), thus enabling a continuous measure of volume status. We investigated whether optimizing plasma volume with the use of EDM would reduce postoperative morbidity and length of hospital stay. METHODS: Following IRB approval and informed consent, patients undergoing "moderate risk" surgical procedures (major urological, major gynecological with laparotomy, and major general surgical with laparotomy) with an anticipated blood loss >500 ml were studied. All patients received a standardized balanced anesthetic technique. After induction of anesthesia, an EDM probe was inserted via the patient's mouth and positioned in mid-esophagus. Patients were randomized into therapy (T) or control (C) groups. In the T group, intraoperative fluid management was guided by a protocol with 200 ml aliquot of Hespan[trade mark sign] (up to a total of 20 ml/kg) given to obtain a maximum stroke volume and corrected flow time. This procedure was repeated every 15 min until the end of surgery. Lactated Ringer's was used when the Hespan[trade mark sign] maximum volume (20 ml/kg) was reached. Patients in the control group have their fluid managed based on clinical criteria. The EDM parameters were not displayed in the C group (the monitor screen was covered with an opaque card). Data on intraoperative hemodynamics, hospital stay and morbidity were collected. Wilcoxon rank sum test and Fisher exact test were used to analyze data. RESULTS: Forty four patients (Therapy = 21, Control = 23) have completed the study to date. Patient demographics, type and duration of procedures were comparable between the groups. The intraoperative fluid administered, hemodynamic data and recovery data are shown in Table 1 below. One patient in the control group developed postoperative renal dysfunction. There was no difference in blood or blood product usage between groups.Table 1DISCUSSION: Intraoperative fluid optimization guided by EDM appears to be associated with faster recovery and shorten hospital stay.

S180 INTRODUCTION: Plasma volume expansion in the perioperative period has been shown to improve patient outcome [1]. The intraoperative use of 6% hetastarch in saline can interfere with coagulation. Thromboelastography (TEG) is a clinically useful test for monitoring dynamic coagulation processes. In a prospective, randomized study, we examined the coagulation effect of intraoperative plasma volume expansion with Hespan[registered sign] (Hes) versus crytalloid (lactated Ringer's solution) using TEG. METHODS: Following IRB approval and written informed consent, patients undergoing either general, urological, orthopedic or gynecological procedures with an anticipated blood loss of > 500 ml were randomly assigned to receive either Hes or lactated Ringer's solution (LR) based on a fluid administration protocol. Red blood cells and blood products were administered when clinically indicated and supported by laboratory evidence. All patients received a standardized general anesthetic. A maintenance fluid of 5 ml/kg/h LR was infused. Native blood for TEG tracings was drawn at induction of anesthesia (Baseline), skin closure (EOS) and the day after surgery (DAS), and transferred to prewarmed TEG cuvettes within 4 min. The mean +/- SE of TEG parameters for r time (normal range 19-28 mm), k time (8-13 mm), maximum amplitude (MA) (48-60 mm) and alpha angle (29-43) for the various times were calculated. Wilcoxon Sign Rank test and Wilcoxon 2-sample Rank Sum test were used to test the mean change within each group and between groups. A p value < 0.05 is considered significant. RESULTS: A total of 58 patients completed the study, 28 and 30 patients in the Hes and LR groups respectively. Demographic data were comparable. The mean total volumes +/- SD of Hes and LR administered were 1300 +/- 1079 and 5546 +/- 2089 ml respectively. Patients in the Hes group exhibited a hypocoagulable trace (prolonged r times, reduced MA and alpha angle) at the end of surgery. However, patients in the LR group exhibited a hypercoagulable trace (shortened r and k times, greater MA and alpha angle- see Figure 1 and Figure 2). Intraoperative blood loss was similar between the groups. However, the mean volume (ml) of intraoperative use of RBC (348 vs. 303), FFP (68 vs 0), platelets (16 vs 0) and cryoprecipitate (3 vs 0) was more in the Hes group. In both groups, the TEG tracings returned to baseline the day after surgery.Figure 1Figure 2DISCUSSION: The administration of crystalloid was associated with a hypercoagulable state intraoperatively. This may be reflected by the reduced volume of RBC transfusion and absence of other blood product usage.

Background: Whole body hyperthermia induced by radiative systems has been used in therapy of malignant diseases for more than ten years.Von Ardenne and co-workers have developed the 'systemiche Krebs-Mehrschritt-Therapic' (sKMT), a combined regime including whole body hyperthermia of 42°C, induced hyperglycaemia and relative hyperoxaemia with additional application of chemotherapy.This concept has been employed in a phase I/II clinical study for patients with metastatic colorectal carcinoma at the Virchow-Klinikum since January 1997.Methods: The sKMT concept was performed eleven times under intravenous general anaesthesia, avoiding volatile anaesthetics.Core temperatures of up to 42°C were reached stepwise by warming with infrared-A-radiation (IRATHERM 2000®).During the whole procedure blood glucose levels of 380-450 mg/dl were maintained as well as PaO 2 levels above 200 mmHg.Extensive invasive monitoring was performed in all patients including measurements with the REF-Ox-Pulmonary artery catheter with continuous measuring of mixed venous saturation (Baxter Explorer®) and invasive monitoring of arterial blood pressure.Data for calculation of hemodynamic and gas exchange parameters were collected four times, at temperatures of 37°C, 40°C, 41.8-42°C and 39°C, during measurements FiO 2 was 1.0 at all times.Fluids were given in order to keep central-venous and Wedge pressure within normal range during the whole procedure.Statistics were performed using the Wilcoxon Test.Results: Statistically significant differences were found between heart rate, cardiac index and systemic vascular resistance comparing data at 37°C and 42°C.Heart rate and cardiac index increased to a maximum at 42°C (P < 0.0001) whereas systemic vascular resistance had its minimum at 42°C (P < 0.0001).Mean arterial pressure dropped with increasing temperature, differences were not significant.Calculation of stroke volume index and ventricular volumes showed only a slight decrease in endsystolic volumes with increasing temperature, the resulting differences in right ventricular ejection fraction were marginally significant (P = 0.038) comparing 42°C to baseline.Right ventricular stroke work index as well as mean pulmonary arterial pressure increased at 42°C (P = 0.0115 and P = 0.0037), pulmonary vascular resistance only dropped little compared to systemic vascular resistance, left ventricular stroke work index even dropped with increasing temperature, though showing no significant difference.Values for mixed venous oxygen saturation did not vary during therapy, pulmonary right-left shunt showed a temperature associated increase (P = 0.0323) to a maximum at 42°C.Conclusion: Under the procedure of sKMT cardiac function in patients, who do not have any pre-existing cardiac impairment, can be maintained almost unchanged, ie with normal right and left ventricular pressure, despite an increase in right ventricular stroke work