Methods: In a prospective, randomized, partially blinded study, 168 cardiac surgery patients at high risk for bleeding received either a full-dose aprotinin infusion, tranexamic acid (10-mg/kg load, 1-mg [middle dot] kg-1 [middle dot] h-1 infusion), tranexamic acid with pre-cardiopulmonary bypass autologous whole-blood collection (12.5% blood volume) and reinfusion after cardiopulmonary bypass (combined therapy), or saline infusion (placebo group).
Results: There were complete data in 160 patients. The aprotinin (n = 40) and combined therapy (n = 32) groups (data are median [range]) had similar reductions in blood loss in the first 4 h in the intensive care unit (225 [40-761] and 163 [25-760] ml, respectively;P = 0.014), erythrocyte transfusion requirements in the first 24 h in the intensive care unit (0 [0-3] and 0 [0-3] U, respectively;P = 0.004), and durations of time from end of cardiopulmonary bypass to discharge from the operating room (92 [57-215] and 94 [37, 186] min, respectively;P = 0.01) compared with the placebo group (n = 43). Ten patients in the combined therapy group (30.3%) required transfusion of the autologous blood during cardiopulmonary bypass for anemia. 相似文献
Methods: Forty-four patients scheduled to undergo elective spinal fusion were randomly assigned to receive either 100 mg/kg tranexamic acid before incision followed by an infusion of 10 mg [middle dot] kg-1 [middle dot] h-1 during surgery (tranexamic acid group) or 0.9% saline (placebo group). General anesthesia was administered according to a standard protocol. Blood loss, transfusion requirements, coagulation parameters, and complications were assessed.
Results: In the tranexamic acid group, blood loss was reduced by 41% compared with placebo (1,230 +/- 535 vs. 2,085 +/- 1,188 ml; P < 0.01). The amount of blood transfused did not differ between groups (615 +/- 460 vs. 940 +/- 718 ml; P = 0.08). Administration of tranexamic acid was a multivariate predictor of blood loss, as was American Society of Anesthesiologists physical status and preoperative platelet count. No apparent adverse drug effects occurred in any patient. 相似文献
Methods: Twenty-one critically ill ventilated children aged 1 week to 12 yr were sedated with 4-6 mg [middle dot] kg-1 [middle dot] h-1 of 2% propofol for up to 28 h, combined with a constant morphine infusion. Whole blood concentration of propofol was measured at steady state and for 24 h after infusion using high-performance liquid chromatography.
Results: A propofol infusion rate of 4 mg [middle dot] kg-1 [middle dot] h-1 achieved adequate sedation scores in 17 of 20 patients. In 2 patients the dose was reduced because of hypotension, and 1 patient was withdrawn from the study because of a increasing metabolic acidosis. Mixed-effects population models were fitted to the blood propofol concentration data. The pharmacokinetics were best described by a three-compartment model. Weight was a significant covariate for all structural model parameters; Cl, Q2, Q3, V1, and V2 were proportional to weight. Estimates for these parameters were 30.2, 16.0, and 13.3 ml [middle dot] kg-1 [middle dot] min-1 and 0.584 and 1.36 l/kg, respectively. The volume of the remaining peripheral compartment, V3, had a constant component (103 l) plus an additional weight-related component (5.67 l/kg). Values for Cl were reduced (typically by 26%) in children who had undergone cardiac surgery. 相似文献
Methods: Sixteen patients were randomly assigned to undergo a 6-h stable isotope infusion study (3 h fasted, 3 h feeding) on the second day after colorectal surgery performed with or without perioperative epidural blockade. Protein synthesis, breakdown and oxidation, glucose production, and clearance were measured by l-[1-13C]leucine and [6,6-2H2]glucose.
Results: Epidural blockade did not affect protein and glucose metabolism in the fasted state. Parenteral alimentation decreased endogenous protein breakdown and glucose production to the same extent in both groups. Administration of glucose and amino acids was associated with an increase in whole body protein synthesis that was modified by the type of analgesia, i.e., protein synthesis increased by 13% in the epidural group (from 93.3 +/- 16.6 to 104.5 +/- 11.1 [mu]mol [middle dot] kg-1 [middle dot] h-1) and by 4% in the patient-controlled analgesia group (from 90.0 +/- 27.1 to 92.9 +/- 14.8 [mu]mol [middle dot] kg-1 [middle dot] h-1;P = 0.054). 相似文献
Methods: Twenty-five volunteers were subjected to three treatment regimens. A standardized first-degree burn injury was induced. On appearance of primary and secondary hyperalgesia, one of the following infusion schemes was applied in a randomized, double-blind, cross-over fashion: (1) infusion of naloxone (0.8 mg/15 min followed by 0.4 mg/h), succeeded by infusion of ketamine (0.3 mg [middle dot] kg-1 [middle dot] 15 min-1 followed by 0.3 mg [middle dot] kg-1 [middle dot] h-1); (2) infusion of placebo, succeeded by infusion of ketamine (0.3 mg [middle dot] kg-1 [middle dot] 15 min-1 followed by 0.3 mg [middle dot] kg-1 [middle dot] h-1); and (3) infusion of placebo, succeeded by infusion of placebo. Heat-pain detection thresholds, magnitude of secondary hyperalgesia around the burn injury, and side effects were determined.
Results: Ketamine reduced secondary hyperalgesia. Naloxone did not affect the action of ketamine. The magnitudes of side effects were equal if the subjects received ketamine, regardless of preceding infusion of naloxone. 相似文献
Methods: Forty patients scheduled to undergo laparoscopic colectomy were randomly allocated to receive intravenous lidocaine (bolus injection of 1.5 mg/kg lidocaine at induction of anesthesia, then a continuous infusion of 2 mg [middle dot] kg-1 [middle dot] h-1 intraoperatively and 1.33 mg [middle dot] kg-1 [middle dot] h-1 for 24 h postoperatively) or an equal volume of saline. All patients received similar intensive postoperative rehabilitation. Postoperative pain scores, opioid consumption, and fatigue scores were measured. Times to first flatus, defecation, and hospital discharge were recorded. Postoperative endocrine (cortisol and catecholamines) and metabolic (leukocytes, C-reactive protein, and glucose) responses were measured for 48 h. Data (presented as median [25-75% interquartile range], lidocaine vs. saline groups) were analyzed using Mann-Whitney tests. P < 0.05 was considered statistically significant.
Results: Patient demographics were similar in the two groups. Times to first flatus (17 [11-24] vs. 28 [25-33] h; P < 0.001), defecation (28 [24-37] vs. 51 [41-70] h; P = 0.001), and hospital discharge (2 [2-3] vs. 3 [3-4] days; P = 0.001) were significantly shorter in patients who received lidocaine. Lidocaine significantly reduced opioid consumption (8 [5-18] vs. 22 [14-36] mg; P = 0.005) and postoperative pain and fatigue scores. In contrast, endocrine and metabolic responses were similar in the two groups. 相似文献
Methods: Consenting patients undergoing elective coronary artery surgery received one of two loading doses of EACA, 30 mg/kg (group I, n = 7) or 100 mg/kg (group II, n = 6) after CPB, or (group III) a 100 mg/kg loading dose before CPB and a 10 mg [middle dot] kg-1 [middle dot] h-1 maintenance infusion continued for 4 h during and after CPB (n = 7). Two patients with renal failure received EACA in the manner of group III. Blood concentrations of EACA, measured by high-performance liquid chromatography, were subjected to mixed-effects pharmacokinetic modeling.
Results: The EACA concentration data were best fit by a model with two compartments and corrections for CPB. The elimination rate constant k10 fell from 0.011 before CPB to 0.0006 during CPB, returning to 0.011 after CPB. V1 increased 3.8 l with CPB and remained at that value thereafter. Cl1 varied from 0.08 l/min before CPB to 0.007 l/min during CPB and 0.13 l/min after CPB. Cl2 increased from 0.09 l/min before CPB to 0.14 l/min during and after CPB. Two patients with renal failure demonstrated markedly reduced clearance. Using their model, the authors predict that an EACA loading infusion of 50 mg/kg given over 20 min and a maintenance infusion of 25 mg [middle dot] kg-1 [middle dot] h-1 would maintain a nearly constant target concentration of 260 [micro sign]g/ml. 相似文献
Methods: Part I study: 54 patients undergoing total abdominal hysterectomy were randomly divided into two groups (n = 27 per group). The patients in the control group received 0.9% sodium chloride solution, whereas the patients in the magnesium group received magnesium (50 mg/kg as a bolus, then 8 mg [middle dot] kg-1 [middle dot] h-1). To maintain mean arterial blood pressure (MAP) and heart rate (HR) at baseline value, the propofol infusion rate was changed when the MAP or the HR changed. The amount of propofol infused excluding the bolus dosage was divided by patient's body weight and total infusion time. Part II study: Another 20 patients were randomly divided into two groups (n = 10 per group). When the MAP and HR had been maintained at baseline value and the propofol infusion rate had been maintained at 80 [mu]g [middle dot] kg-1 [middle dot] min-1 (magnesium group) and 160 [mu]g [middle dot] kg-1 [middle dot] min-1 (control group), bispectral index (BIS) values were measured.
Results: Part I: The mean propofol infusion rate in the magnesium group (81.81 +/- 13.09 [mu]g [middle dot] kg-1 [middle dot] min-1) was significantly less than in the control group (167.57 +/- 47.27). Part II: BIS values in the control group (40.70 +/- 3.89) were significantly less than those in the magnesium group (57.80 +/- 7.32). 相似文献
Methods: Rats received a continuous intrathecal infusion of morphine (0.3-10 [micro sign]g [middle dot] kg-1 [middle dot] h-1), lidocaine (30-1000 [micro sign]g [middle dot] kg-1 [middle dot] h-1), a combination of those, or saline. After 6- day infusion, intrathecal morphine challenge test (5 [micro sign]g/10 [micro sign]l) was performed, and time-response curve was constructed to assess the magnitude of tolerance. The tail flick (TF) test and colorectal distension (CD) test were used to measure somatic and visceral antinociceptive effects, respectively.
Results: Antinociceptive effects in the TF and CD tests caused by morphine challenge were reduced (P < 0.01) in the morphine infused groups. The magnitude of the tolerance was inversely associated with the amount of morphine infused. Lidocaine infusion induced no different change in the morphine challenge test from that seen in the saline infusion group. Development of tolerance was greater in morphine 3 [micro sign]g [middle dot] kg-1 [middle dot] h-1 than in morphine 0.75 [micro sign]g [middle dot] kg-1 [middle dot] h-1 + lidocaine 150 [micro sign]g [middle dot] kg-1 [middle dot] h-1 despite their similar antinociceptive effects during intrathecal infusion. The infusion of a low dose of morphine (0.3 [micro sign]g [middle dot] kg-1 [middle dot] h-1) did not reduce the antinociceptive effects in the challenge test. 相似文献
Methods: Sixty patients participated in this randomized double-blinded study. Patients received lidocaine 1% (lidocaine group) with a 1.5 mg/kg-1 intravenous bolus in 10 min followed by a 1.5 mg [middle dot] kg-1 [middle dot] h-1 intravenous infusion or saline (control group). These regimens were started 30 min before surgical incision and stopped 1h after skin closure. Lidocaine blood concentrations were measured at the end of administration. In both groups, postoperative analgesia was provided exclusively by patient-controlled intravenous morphine. Pain scores, morphine consumption, and operative hip flexion were recorded over 48 h. In addition, pressure pain thresholds and the extent of hyperalgesia around surgical incision were systematically measured at 24 and 48 h.
Results: In comparison with the placebo, lidocaine did not induce any opioid-sparing effect during the first 24 h (median [25-75% interquartile range]; 17 mg [9-28] vs. 15 mg [8-23]; P = 0.54). There was no significant difference regarding the effects of lidocaine and placebo on pain score, pressure pain thresholds, extent in the area of hyperalgesia, and maximal degree of active hip flexion tolerated. Mean plasma lidocaine concentration was 2.1 +/- 0.4 [mu]g/ml. 相似文献
Methods: Seventy-four adult patients undergoing primary coronary artery bypass surgery were randomized to receive 125 mg/kg [Greek small letter epsilon]-ACA followed by an infusion of 12.5 mg [middle dot] kg-1 [middle dot] h-1 or an equivalent volume of saline. Coagulation studies, thromboelastography, and platelet aggregation tests were performed preoperatively, after bypass, and on the first postoperative day. Mediastinal drainage was recorded during the 24 h after surgery. Homologous blood transfusion triggers were predefined and transfusion amounts were recorded.
Results: One patient was excluded for surgical bleeding and five patients were excluded for transfusion against predefined criteria. One patient died from a dysrhythmia 2 h postoperatively. Among the remaining 67, the [Greek small letter epsilon]-ACA group had less mediastinal blood loss during the 24 h after surgery, 529 +/- 241 ml versus 691 +/- 286 ml (mean +/- SD), P < 0.05, despite longer cardiopulmonary bypass times and lower platelet counts, P < 0.05. Platelet aggregation was reduced in both groups following cardiopulmonary bypass but did not differ between groups. Homologous blood transfusion was similar between both groups. 相似文献
Methods: Blood samples were taken from 55 patients of American Society of Anesthesiologists grade 1-3 scheduled for elective intracranial procedures (n = 47) or for pulmonectomy (n = 8). All patients were premedicated with diazepam (10 mg) administered orally 2 h before anesthesia. Propofol total intravenous anesthesia was performed at the following infusion rates: 12 mg [middle dot] kg-1 [middle dot] h-1, 9 mg [middle dot] kg-1 [middle dot] h-1, and 6 mg [middle dot] kg-1 [middle dot] h-1. Fentanyl and pancuronium bromide were also administered intermittently. After tracheal intubation, the lungs were ventilated to normocapnia with an oxygen-air mixture (fraction of inspired oxygen = 0.33). Blood samples for propofol and 2,6-diisopropyl-1,4-quinol analysis were taken simultaneously from the right atrium and the radial artery, or the pulmonary artery and the radial artery. The concentration of both substances were measured with high-performance liquid chromatography and gas chromatography-mass spectroscopy.
Results: The concentration of propofol in the central venous system (right atrium or pulmonary artery) is greater than in the radial artery, whereas the opposite is observed for propofol's metabolite, 2,6-diisopropyl-1,4-quinol. Higher propofol concentrations are found in blood taken from the pulmonary artery than in the blood collected from the radial artery. 相似文献
Methods: C fiber-evoked potentials were recorded in the superficial laminae I-II of the rat lumbar spinal cord with glass microelectrodes in response to electrical stimulation of the sciatic nerve. High-frequency stimulation was applied on the sciatic nerve to induce long-term potentiation of C fiber-evoked field potentials, a form of central sensitization. To test the effect of fentanyl on acute nociception, fentanyl was infused intravenously at increasing doses (6-192 [mu]g [middle dot] kg-1 [middle dot] h-1). One hour after start of infusion, high-frequency stimulation was applied to evaluate effects of fentanyl on the induction of long-term potentiation.
Results: In the absence of fentanyl, high-frequency stimulation potentiated C fiber-evoked field potentials to 149 +/- 12% of controls (mean +/- SEM; n = 6) for at least 1 h. Increasing doses of fentanyl led to a significant reduction of C fiber-evoked potentials in a dose-dependent manner. The induction of long-term potentiation was blocked by low doses of fentanyl (infusion 12-48 [mu]g [middle dot] kg-1 [middle dot] h-1). At high doses, fentanyl did not block the induction of long-term potentiation (infusion 96-192 [mu]g [middle dot] kg-1 [middle dot] h-1). 相似文献
Methods: Forty-six adult patients were randomized to placebo or colforsin daropate treatment. Patients in the control group received normal saline; patients in the colforsin group received 0.75 [mu]g [middle dot] kg-1 [middle dot] min-1 colforsin daropate intravenously until the study ended. Thirty minutes after the study began, the authors administered 5 mg/kg thiamylal and 5 [mu]g/kg fentanyl for induction of general anesthesia and 0.3 mg/kg vecuronium for muscle relaxation. A 15-mg [middle dot] kg-1 [middle dot] h-1 continuous infusion of thiamylal followed anesthetic induction. Four, 8, 12, and 16 min after tracheal intubation, mean airway resistance (Rawm), expiratory airway resistance (Rawe), and dynamic lung compliance (Cdyn) were measured.
Results: Patients in the colforsin group had significantly lower Rawm and Rawe and higher Cdyn after intubation than those in the control group. Differences in Rawm, Rawe, and Cdyn between the two groups persisted through the final measurement at 16 min. At 4 min after intubation, smokers had a higher Rawm and a lower Cdyn than nonsmokers in the control group. After treatment by intravenous colforsin daropate, Rawm, Rawe, and Cdyn values were similar for smokers and nonsmokers after tracheal intubation. 相似文献
Methods: Three propofol infusions (25 mg [middle dot] kg-1 [middle dot] h-1 for 10 min, 22 mg [middle dot] kg-1 [middle dot] h-1 for 10 min, and 12.5 mg [middle dot] kg-1 [middle dot] h-1 for 20 min) were administered to 10 patients during extradural analgesia. Each successive infusion was started immediately after the patient had regained responsiveness after termination of the preceding infusion. Electroencephalography was recorded from bilateral prefrontal to mastoid leads. Electroencephalographic amplitude in the 11- to 15-Hz band and the Bispectral Index were used as electroencephalographic effect variables. PKPD parameters were calculated with use of parametric and nonparametric models based on electroencephalographic data and arterial propofol concentrations derived during the initial infusion, and these were used to predict electroencephalographic effect during the subsequent infusions. The predictability of the electroencephalographic effects was determined by the coefficient of determination (R2) and of the -2 log likelihood of the sequential infusions.
Results: The direction of electroencephalographic changes in response to the infusions was reproducible. Although PKPD parameters could be estimated well during the initial infusion (median [range] parametric R2 = 0.74 [0.56-0.95] for electroencephalographic amplitude and 0.90 [0.27-0.99] for Bispectral Index), none of the modeling techniques could predict accurately the electroencephalographic effect during subsequent infusions (R2 = 0.00 [-0.31-0.46] for electroencephalographic amplitude and 0.15 [-0.46-0.57] for Bispectral Index;P < 0.01). 相似文献
Methods: With institutional review board approval and written informed consent, 120 adult patients scheduled to undergo minor orthopedic surgery were randomized to receive a propofol-remifentanil anesthetic controlled by Narcotrend, by BIS(R), or solely by clinical parameters. Anesthesia was induced with 0.4 [mu]g [middle dot] kg-1 [middle dot] min-1 remifentanil and a propofol target-controlled infusion at 3.5 [mu]g/ml. After intubation, remifentanil was reduced to 0.2 [mu]g [middle dot] kg-1 [middle dot] min-1, whereas the propofol infusion was adjusted according to clinical parameters or to the following target values: during maintenance to D0 (Narcotrend) or 50 (BIS(R)); 15 min before the end of surgery to C1 (Narcotrend) or 60 (BIS(R)). Recovery times were recorded by a blinded investigator, and average normalized propofol consumption was calculated from induction and maintenance doses.
Results: The groups were comparable for demographic data, duration of anesthesia, and mean remifentanil dosages. Compared with standard practice, patients with Narcotrend or BIS(R) monitoring needed significantly less propofol (standard practice, 6.8 +/- 1.2 mg [middle dot] kg-1 [middle dot] h-1vs. Narcotrend, 4.5 +/- 1.1 mg [middle dot] kg-1 [middle dot] h-1 or BIS(R), 4.8 +/- 1.0 mg [middle dot] kg-1 [middle dot] h-1;P < 0.001), opened their eyes earlier (9.3 +/- 5.2 vs. 3.4 +/- 2.2 or 3.5 +/- 2.9 min), and were extubated sooner (9.7 +/- 5.3 vs. 3.7 +/- 2.2 or 4.1 +/- 2.9 min). 相似文献
Methods: Fifty adult patients undergoing major abdominal surgery were randomly assigned to two anesthetic regimens: (1) desflurane was kept constant at 0.5 minimum alveolar concentrations and a remifentanil infusion was titrated to autonomic responses (remifentanil group); or (2) remifentanil at 0.1 [mu]g [middle dot] kg-1 [middle dot] min-1 and desflurane titrated to autonomic responses (desflurane group). All patients were given a bolus of 0.15 mg/kg morphine 40 min before the end of surgery. Morphine was initially titrated to need by postanesthesia care nurses blinded to group assignment. Subsequently, patients-who were also blinded to group assignment-controlled their own morphine administration. Pain scores and morphine consumption were recorded for 24 postoperative h.
Results: The mean remifentanil infusion rate was 0.3 +/- 0.2 [mu]g [middle dot] kg-1 [middle dot] min-1 in the remifentanil group, which was significantly greater than in the desflurane group. Intraoperative hemodynamic responses were similar in each group. Postoperative pain scores were significantly greater in the remifentanil group. These patients required morphine significantly earlier than those in the desflurane group and needed nearly twice as much morphine in the first 24 postoperative h: 59 mg (25-75% interquartile range, 43-71) versus 32 mg (25-75% interquartile range, 19-59;P < 0.01). 相似文献
Methods: Fifty young adult patients undergoing intestinal surgery under general anesthesia with propofol were studied. At induction, the patients received epidurally either an initial dose of 2 micro gram/kg clonidine followed by an infusion of 0.5 micro gram [center dot] kg-1 [center dot] h-1 (group 1, n = 10) or 4 micro gram/kg followed by 1 micro gram [center dot] kg-1 [center dot] h-1 (group 2, n = 20) or 8 micro gram [center dot] kg-1 [center dot] h-1 followed by an infusion of 2 micro gram [center dot] kg-1 [center dot] h-1 (group 3, n = 20). During the operation, increases in arterial blood pressure or heart rate that did not respond to a propofol bolus (0.5 mg/kg) were treated with a bolus of intravenous lidocaine (1 mg/kg). Three successive injections were allowed. When baseline values were not restored, opioids were added and the patient was removed from the study. After operation, the clonidine infusions were maintained for 12 h. During this period and at every 30 min, sedation scores and visual analog scale values at rest and at cough were noted. In case of subjective scores up to 5 cm at rest or up to 8 cm at cough, the patients were given access to a patient-controlled analgesia device that delivered epidural bupivacaine. The end point of the study was reached once the patient activated the analgesic delivery button.
Results: During surgery, 60% of patients in group 1 compared with 33% of patients in group 2 and only 5% of patients in group 3 were removed from the study protocol because of inadequate anesthesia (P < 0.05). After operation, epidural clonidine provided complete analgesia lasting 30 +/- 21 min in group 1 compared with 251 + 237 min in group 2 or 369 +/- 256 min in group 3 (P < 0.05 for group 1 vs. groups 2 and 3 and group 2 vs. group 3). 相似文献
Methods: Cerebral ischemia was induced in awake Wistar rats by a local intracerebral injection of the potent vasoconstrictor, endothelin (6 pmol in 3 [mu]l) into the striatum. Propofol treatment after ischemia was delayed up to 4 h, and the infusion period shortened from 4 h to 1 h. Infarct volume was assessed 3 or 21 days after the stroke. Neurologic outcome was evaluated on days 14-21 after ischemia. Tissue ascorbate and glutathione concentrations were evaluated at 4 h and 3 days after ischemia.
Results: Infarct volumes were reduced 3 days after ischemia when propofol treatment (25 mg [middle dot] kg-1 [middle dot] h-1) was delayed for 2 h (0.5 +/- 0.3 mm3) but not 4 h (2.0 +/- 0.9 mm3), compared with intralipid controls (2.4 +/- 0.7 mm3). The propofol infusion period of 3 h but not 1 h reduced infarct volume. Propofol treatment did not reduce infarct volume 21 days after the stroke, although motor function improvements (Montoya staircase test) were observed 14-21 days after the stroke. Propofol neuroprotection was independent of tissue ascorbate and glutathione concentrations. 相似文献