Haemodynamic and plasma vasopressin responses during high-dose fentanyl or sufentanil anaesthesia

This study compared the haemodynamic and arginine vasopressin responses of patients to fentanyl or sufentanil anaesthesia for coronary artery bypass surgery. Fourteen normotensive patients with normal left ventricular function were studied. Patients were induced with fentanyl (N = 7) 37.5 micrograms X kg-1 or sufentanil (N = 7) 7.5 micrograms X kg-1 by intravenous infusion over three minutes. Clinically important chest wall rigidity, bradycardia and recall of intraoperative events did not occur. All of the fentanyl patients became hypertensive after induction and five required vasodilator therapy since they did not respond to boluses of fentanyl (12.5 micrograms X kg-1). Two of these five patients had S-T depression greater than 1 mm. Five patients in the sufentanil group became hypertensive after induction. Four of these patients responded to additional sufentanil (3.75 micrograms X kg-1) while one required vasodilator therapy for concomitant S-T depression. Sufentanil attenuated the increase of arginine vasopressin during cardiopulmonary bypass. Levels of arginine vasopressin in the fentanyl group were significantly higher than those of the sufentanil group during bypass. Levels of AVP after bypass were higher in the sufentanil group. The incidence of hypertension was similar in both groups. The hypertension was more easily treated with sufentanil but concomitant vasodilators (nitroglycerine) were required in both patient groups. Neither fentanyl in doses up to 128 +/- 8.7 micrograms X kg-1 nor sufentanil in doses up to 23 +/- 1.4 micrograms X kg-1 can be used as sole agents for anaesthesia in adult coronary artery bypass patients with good ventricular function when induction times are three minutes and bolus top-up doses are used.     

Effect of bolus dose of remifentanil on haemodynamic response to tracheal intubation

A randomized placebo-controlled double-blinded study was conducted in 40 ASA 1 and 2 patients to determine the dose response of remifentanil in attenuating the haemodynamic response to tracheal intubation. Patients were allocated to one of four groups: placebo, remifentanil 1 microgram.kg-1, remifentanil 2 micrograms.kg-1 and remifentanil 4 micrograms.kg-1. A propofol target-controlled infusion was started at 4 micrograms.ml-1 and incrementally titrated to loss of verbal contact. Muscle relaxation was provided by cisatracurium. The study drug was given three minutes later over 30 seconds, and 90 seconds later the patient's trachea was intubated under direct laryngoscopy. Baseline noninvasive blood pressure and heart rate recordings were made prior to starting target-controlled infusion, then at one-minute intervals after loss of verbal contact for the duration of the study. Demographic data and target-controlled infusion rate at intubation was similar for the groups. Following intubation, heart rate increased by 15% in the placebo group, 10% in 1 microgram.kg-1 group, with no changes in 2 micrograms.kg-1 and 4 micrograms.kg-1 groups. Systolic blood pressure following intubation increased by 30% in the placebo group, 10% in the 1 microgram.kg-1 group and remained unchanged in the 2 micrograms.kg-1 and 4 micrograms.kg-1 groups. Remifentanil 1 microgram.kg-1 attenuated the rise in heart rate and systolic blood pressure. Remifentanil 2 micrograms.kg-1 blocked the haemodynamic response completely: no further benefit was shown from increasing the dose to 4 micrograms.kg-1.     

Bolus dose remifentanil for control of haemodynamic response to tracheal intubation during rapid sequence induction of anaesthesia

The effect of three bolus doses of remifentanil on the pressor response to laryngoscopy and tracheal intubation during rapid sequence induction of anaesthesia was assessed in a randomized, double-blind, placebo- controlled study in four groups of 20 patients each. After preoxygenation, anaesthesia was induced with thiopental 5-7 mg kg-1 followed immediately by saline (placebo) or remifentanil 0.5, 1.0 or 1.25 micrograms kg-1 given as a bolus over 30 s. Cricoid pressure was applied just after loss of consciousness. Succinylcholine 1 mg kg-1 was given for neuromuscular block. Laryngoscopy and tracheal intubation were performed 1 min later. Arterial pressure and heart rate were recorded at intervals until 5 min after intubation. Remifentanil 0.5 microgram kg-1 was ineffective in controlling the increase in heart rate and arterial pressure after intubation but the 1.0 and 1.25 micrograms kg-1 doses were effective in controlling the response. The use of the 1.25 micrograms kg-1 dose was however, associated with a decrease in systolic arterial pressure to less than 90 mm Hg in seven of 20 patients.      

A single dose of milrinone facilitates separation from cardiopulmonary bypass in patients with pre-existing left ventricular dysfunction

Milrinone is used during cardiac surgery to facilitate separation from cardiopulmonary bypass (CPB) and/or to treat myocardial dysfunction in the post-bypass period. We have demonstrated, in patients with preoperative depression of systolic function undergoing aorto-coronary artery bypass surgery, sustained improvement in cardiac function after a single loading dose of milrinone 50 micrograms kg-1, administered at the end of bypass, thus significantly decreasing the need for beta- agonist therapy.      

Assessment of intubating conditions in adults after induction with propofol and varying doses of remifentanil

We have assessed intubating conditions in three groups of 60 ASA I or II patients after induction of anaesthesia with propofol 2 mg kg-1 and remifentanil 0.5, 1.0 or 2.0 micrograms kg-1. Tracheal intubation was graded according to ease of laryn-goscopy, position of the vocal cords, coughing, jaw relaxation and movement of the limbs. Intubation was successful in 80%, 90% and 100% of patients after remifentanil 0.5, 1.0 or 2.0 micrograms kg-1, respectively. Overall intubating conditions were regarded as acceptable in 20%, 50% and 80% of patients, respectively. All three groups had a decrease in arterial pressure after induction but there was no difference between groups. The decrease in arterial pressure was not regarded as clinically significant. Intubating conditions were best after induction with remifentanil 2 micrograms kg and propofol 2 mg kg-1.      

The effect of olprinone administered after cardio-pulmonary bypass during open heart surgery, evaluated by its plasma concentrations and hemodynamic changes]

Plasma concentrations and hemodynamic effects of olprinone were evaluated in seventeen patients undergoing open heart surgery. The patients were randomized into the bolus group (15 micrograms.kg-1 bolus dose +0.1 microgram.kg-1.min-1 infusion, n = 9) and the non-bolus group (0.1 microgram.kg-1.min-1 infusion, n = 8). Plasma concentrations and hemodynamic variables were measured before CPB (cardiopulmonary bypass; baseline), 5, 60 min after weaning from CPB, and 3, 6 hours after the end of surgery. Plasma concentrations in the non-bolus group were significantly lower than those of bolus group at any point except for 3 hours after the end of surgery. In the bolus group, increases in the cardiac index and stroke volume index were significantly higher compared with the non-bolus group. From these results we conclude that olprinone given in bolus (15 micrograms.kg-1) followed by continuous infusion (0.1 microgram.kg-1.min-1) is efficacious and safe during weaning from CPB.     

Hemodynamic effects of fentanyl and sufentanil combined with flunitrazepam in coronary artery surgery

Because sufentanil has been reported as being able to prevent or treat peroperative hypertensive crises during aorto-coronary artery graft surgery, a study was carried out to compare the haemodynamic effects of sufentanil with those of fentanyl. 20 patients who were to undergo aortocoronary bypass grafting (CABG) were randomly allocated to two equal groups, sufentanil (Sf) and fentanyl (F) groups. A 1 to 5 dose ratio was used so as to have equipotent doses of sufentanil and fentanyl. Induction doses were 10 micrograms.kg-1 sufentanil and 50 micrograms.kg-1 fentanyl. Up to 20 micrograms.kg-1 sufentanil and 100 micrograms.kg-1 fentanyl were then used between intubation and the setting-up of cardiopulmonary bypass (CPB). A bolus of 10 micrograms.kg-1 flunitrazepam was given if necessary, so as to lower the mean arterial pressure (Pa) to below 100 mmHg after intubation, and under 80 mmHg during CPB. Heart rate, Pa, mean pulmonary arterial pressure, pulmonary wedge pressure (Ppw), central venous pressure and cardiac output were measured before anaesthesia, 2 min after intubation, before incision, 2 min after sternotomy, 10 min after the end of CPB, after chest closure, 30 min and 2h after arrival of the patient in the intensive care unit. The only difference found between the two groups was a more rapid drop in left ventricular preload after induction with sufentanil; 2 min after intubation, there was a 26% fall in Ppw with sufentanil (p less than 0.01) and 8% with fentanyl. Before skin incision, this drop was of 32% (p less than 0.01) and 24% (p less than 0.01) respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

The pharmacokinetics of remifentanil in patients undergoing coronary artery bypass grafting with cardiopulmonary bypass.

Remifentanil is a potent opioid with a short duration of action. It has the potential for large-dose opioid anesthesia without an obligatory prolonged period of mechanical ventilation. However, because of high clearance and rapid tissue distribution, cardiopulmonary bypass (CPB) may influence its pharmacokinetics and alter drug requirements. We administered remifentanil by continuous infusion to 68 patients having coronary artery bypass graft surgery during CPB with hypothermia to describe the effects of these interventions on its pharmacokinetics. Remifentanil concentrations were measured before, during, and after CPB. Disposition was best described by a two-compartment model. The volume of distribution increased by 86% with institution of CPB and remained increased after CPB. Elimination clearance decreased by 6.37% for each degree Celsius decrease from 37 degrees C. IMPLICATIONS: Remifentanil concentrations decrease with the institution of cardiopulmonary bypass because of an increase in the volume of distribution. The decrease in elimination clearance with hypothermia results in increased total remifentanil concentrations during cardiopulmonary bypass if the infusion rate is not altered. More constant blood remifentanil levels may be obtained by reducing remifentanil infusion rate by 30% for each 5 degrees C decrease in temperature.     

Effects of dopexamine on blood flow in multiple splanchnic sites measured by laser Doppler velocimetry in rabbits undergoing cardiopulmonary bypass

Decreased gut perfusion has been reported during cardiopulmonary bypass (CPB). Studies of treatments to avoid splanchnic ischaemia during CPB have given conflicting results. We studied 12 rabbits during mild hypothermic non-pulsatile CPB. Tissue blood flow in three different splanchnic areas (gastric, jejunum and ileum) was measured by laser Doppler velocimetry (LDV) before CPB (T0), after steady state (T1), after administration of dopexamine 2 micrograms kg-1 min-1 (T2) and 4 micrograms kg-1 min-1 (T3), and after return to baseline (T4). Splanchnic blood flow decreased during CPB. Dopexamine increased significantly jejunum LDV (100% at T1 to mean 271 (SD 210)% at T2) and ileum LDV (100% at T1 to 187 (112)% at T2). Gastric LDV was not altered by infusion of dopexamine during CPB. This could partly explain the conflicting results on the value of gastric tonometry as an index of splanchnic injury.      

Pharmacokinetics of amrinone during cardiac surgery.

Amrinone is a nonglycosidic noncatecholamine with both vasodilator and positive inotropic effects that may be administered to patients undergoing cardiac surgery. As an initial step toward elucidating the optimal dosage of amrinone for cardiac surgical patients we studied the pharmacokinetics of amrinone during and after cardiac surgery requiring cardiopulmonary bypass. The study population comprised 35 adult patients, each receiving a single dose of amrinone (0.75, 1.5, 2.0, or 2.5 mg/kg) administered into the venous reservoir near the end of cardiopulmonary bypass. Additionally, 15 of the 35 patients also received intravenous infusions of either 5 or 10 micrograms.kg-1.min-1. Arterial blood was sampled over the next 22 h, and plasma concentrations of amrinone were determined by high-performance liquid chromatography. Protein binding of amrinone, assayed by equilibrium dialysis, was 21.6 +/- 2.5%. The decay of amrinone concentrations in plasma over time was fit to a biexponential equation by nonlinear least-squares regression. The manufacturer's recommended dose of 0.75 mg/kg followed by an infusion of 10 micrograms.kg-1.min-1 was inadequate to maintain the plasma concentration within the therapeutic range based on the pharmacodynamics of amrinone in patients with chronic congestive heart failure. This was due to significant redistribution of amrinone in the body after the loading dose. To maintain a therapeutic plasma concentration of 1.5-2.0 micrograms/ml, a larger loading dose or a supplemental loading dose as well as a continuous infusion is required.     

A comparison of remifentanil and fentanyl in patients undergoing carotid endarterectomy

BACKGROUND AND AIM: We investigated the haemodynamic stability and emergence characteristics of isoflurane/nitrous oxide anaesthesia supplemented with remifentanil or fentanyl in patients undergoing carotid endarterectomy. METHODS: Anaesthesia was induced with propofol (1-2 mg kg-1) and either remifentanil (0.5 microgram kg-1) or fentanyl (1 microgram kg-1), followed by an infusion of remifentanil (0.2 microgram kg-1 min-1) or fentanyl (2 micrograms kg-1 h-1). RESULTS: There were no significant differences between the groups in haemodynamic variables, postoperative pain, nausea or vomiting. After induction there was a significant decrease in mean arterial pressure for both groups (P < 0.001) and a decrease in heart rate (P = 0.001) in the remifentanil group. In both groups these haemodynamic changes continued during maintenance of anaesthesia (P < 0.05). The time to eye opening after surgery was significantly shorter with remifentanil compared with fentanyl (6.62 +/- 3.89 vs. 18.0 +/- 15.18 min, P = 0.015). CONCLUSION: Remifentanil appears to be a comparable opioid to fentanyl when supplementing isoflurane/nitrous oxide anaesthesia for carotid endarterectomy.     

Dose requirements of infusions of cisatracurium or rocuronium during hypothermic cardiopulmonary bypass

We investigated the influence of mild hypothermic cardiopulmonary bypass (CPB) on the dose requirements of cisatracurium or rocuronium used as a continuous infusion. We studied eight patients given cisatracurium and nine given rocuronium. They were ASA class III and IV and scheduled for elective coronary artery bypass grafting. Neuromuscular transmission was monitored electromyographically. After recovery of T1/T0 to 10%, a cisatracurium infusion or a rocuronium infusion was started at a rate of 1.5 or 10 micrograms kg-1 min-1, respectively, and adjusted to maintain T1/T0 at 15%. Infusion rate and duration were recorded before, during and after CPB in each patient and the mean infusion rates were calculated. One-way ANOVA showed a statistically significant difference between the cisatracurium infusion rates before, during and after CPB: A T1/T0 of 15% could be achieved with a mean infusion rate of 1.1, 0.75 and 0.98 micrograms kg-1 min-1 before, during and after CPB, respectively. There was no significant difference between the rocuronium infusion rates before, during and after CPB. The mean rocuronium infusion rate required to maintain T1/T0 at 15% throughout the procedure was 4.1 micrograms kg-1 min-1. Cisatracurium infusion rates should be halved during CPB. Even after CPB, requirements are reduced. The same tendency occurs with rocuronium, but the changes in infusion rate were not statistically significant.     

Enoximone and warming after hypothermic cardiopulmonary bypass

In a randomized, controlled study of 24 patients undergoing myocardial revascularization, we found that enoximone 0.5 mg kg-1 i.v., followed by 5 micrograms kg-1 min-1, when rewarming after hypothermic cardiopulmonary bypass, prevented subsequent cooling of the periphery after transfer to the intensive care unit. Skin surface temperatures on the foot increased by mean 0.33 (SD 0.5) degree C h-1 in the enoximone group, but decreased by 0.43 (0.4) degree C h-1 in the control group until core temperature had increased to 37 degrees C (P < 0.001); only then did peripheral temperatures begin to increase in the control group. Enoximone did not merely redistribute heat from the core to the periphery. The capacity to transfer heat by the circulation rather than the ability to generate heat in the core appeared to limit body warming in the ICU after hypothermic cardiopulmonary bypass.      

Effects of prostaglandin E1 infusion during cardiopulmonary bypass

Effects of continuous prostaglandin E1 (PGE1) infusion 0.03 micrograms.kg-1.min-1 on hemodynamics, body temperature and urine output during cardiopulmonary bypass (CPB) were studied. Systemic vascular resistance was kept significantly lower in PGE1 administration group than control group. Differences between core and peripheral temperature decreased faster in the PGE1 administration group than the control group. Mean arterial pressure was stable at 40mmHg during CPB in the PGE1 group and 60mmHg in the control group. However, there were no significant differences in urine output between the PGE1 administration group (10.8ml.kg-1.h-1) and the control group (9.4ml.kg-1.h-1). This study indicates that continuous PGE1 infusion (0.03 micrograms.kg-1.min-1) is a method of choice for vasodilation and improvement of peripheral perfusion during hypothermia of CPB.     

An open, randomized comparison of alfentanil, remifentanil and alfentanil followed by remifentanil in anaesthesia for craniotomy

We studied 52 adults undergoing elective craniotomy, allocated randomly to one of three opioid treatments: alfentanil 50 micrograms kg-1 followed by 0.833 microgram kg-1 min-1 until dural closure (group Alf.); alfentanil 50 micrograms kg-1 followed by 0.833 microgram kg-1 min-1 for 2 h, then remifentanil 0.25 microgram kg-1 min-1 (group Alf.- Remi.); or remifentanil 1 microgram kg-1 followed by 0.5 microgram kg-1 min-1 reducing to 0.25 microgram kg-1 min-1 after craniotomy (group Remi.). Anaesthesia was maintained with infusion of propofol and 66% nitrous oxide in oxygen. Infusions of propofol and remifentanil were stopped at head bandaging. Group Remi. had the least intraoperative haemodynamic responses and group Alf. the most (P < 0.05). Times to tracheal extubation and obey commands were similar in all groups. In all patients in group Alf.-Remi. and group Remi., the trachea was extubated 27 min from the end of anaesthesia; three patients in group Alf. were slower to recover. Use of analgesia in the recovery room and time to transfer to the neurosurgical unit were similar in the three groups.      

Vascular effects of ketamine during anesthesia with diazepam and fentanyl]

Twenty-six adults undergoing elective cardiac surgery were anaesthetized with diazepam and fentanyl (induction with 200 micrograms.kg-1 and 30 micrograms.kg-1 respectively, maintenance with incremental doses). Normothermic constant perfusion output cardiopulmonary bypass was carried out with a membrane oxygenator, haemodilution with Ringer's lactate solution, and cardioplegia with St. Thomas's Hospital solution. The patients were randomly assigned to two groups. They were given either 2 mg.kg-1 of ketamine (group 1) or placebo (5 ml of normal saline) (group 2) via the venous line of the oxygenator. The non pulsatile flow was then kept at a steady rate of 2.41 x min-1.m-2, and no other infusion or treatment was started during the study period (ten minutes). The mean arterial pressure and blood reservoir level were measured every min during this period. The systemic vascular resistances did not change significantly in either group, but remained 27% lower in the ketamine group than in the placebo group (p less than 0.01). The blood reservoir level was 37% higher in the ketamine group (p less than 0.01), suggesting a decreased venous capacitance. It is therefore concluded that ketamine leads to venous constriction, and probably arterial dilation, during fentanyl-diazepam anaesthesia and normothermic cardiopulmonary bypass. The venous effects of ketamine could explain why it is usually well tolerated in hypovolaemic states.     

Cardiovascular effects of, and catecholamine response to, high dose fentanyl or NLA in patients for valve replacement]

We measured the cardiovascular effect of, and catecholamine and other hormonal responses to, anesthetic doses of fentanyl and original NLA in 25 patients for open heart surgery. The patients were randomly divided into three groups (group N, F30, F75). During induction, in group N; droperidol 0.25 mg.kg-1 and fentanyl 5 micrograms.kg-1, in group F30; fentanyl 30 micrograms.kg-1, and in group F75; fentanyl 75 micrograms.kg-1 were administered intravenously. Additional fentanyl was administered at a rate of 100 to 200 micrograms.h-1. Droperidol 0.25 mg.kg-1 was administered in group N when cardiopulmonary bypass (CPB) was disconnected. Plasma samples were assayed for norepinephrine, epinephrine, ACTH and cortisol before and after induction, during sternotomy, 60 minutes after institution of CPB, after weaning from CPB, and before as well as after extubation. Heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP) and rate pressure product (RPP) were calculated simultaneously at the blood samplings. In all groups, no remarkable change in cardiovascular dynamics was observed. CPB was associated with marked increases in catecholamines, but high dose fentanyl in dose of 75 micrograms.kg-1 was able to suppress epinephrine level more than in group N. In high dose fentanyl group (F30, F75) ACTH was within normal ranges, even during CPB. The results suggest that high dose fentanyl is a complete anesthetic in patients for cardiac surgery. But a large dose of fentanyl causes small decreases in heart rate and arterial blood pressure. Our data indicate that group F30 is an attractive anesthetic technique for patients with valvular disease.     

Effects of normothermic cardiopulmonary bypass on bispectral index

This study investigated the changes in the hypnotic component of anaesthesia, estimated by the bispectral index of the electroencephalogram, during normothermic cardiopulmonary bypass. Twenty-six patients (20 men, 6 women), aged 61 +/- 11 years (Mean +/- SD) scheduled for cardiac surgery were premedicated with hydroxyzine and meperidine. Anaesthesia was induced and maintained with a computer-controlled continuous infusion (not adjusted for haemodilution) of sufentanil (effect site concentration 0.4-0.6 ng mL-1) and a manually adjusted continuous infusion of propofol (4.4 +/- 1.8 mg kg-1 h-1). Cardiopulmonary bypass was normothermic with moderate haemodilution. Bispectral index was measured with a referential montage before, 30 s, 1, and 3 min after cardiopulmonary bypass onset, before and after aortic cross-clamping, 30 min after cardiopulmonary bypass onset, before and after aorta cross-clamp release and before and after weaning from cardiopulmonary bypass. Bispectral index values were 48 +/- 8 before cardiopulmonary bypass onset, 50 +/- 10 before, and 48 +/- 8 after end of cardiopulmonary bypass (P = NS). No patient had increases in bispectral index values during cardiopulmonary bypass consistent with awakening. We conclude that with the anaesthetic regimen presented in this study bispectral index values do not change during normothermic cardiopulmonary bypass.     

Comparison of different doses of remifentanil on the cardiovascular response to laryngoscopy and tracheal intubation

We have compared three bolus and infusion regimens of remifentanil on the cardiovascular response to laryngoscopy and orotracheal intubation in three groups of 20 ASA I-II female patients, in a randomized, double- blind study. Patients in group 1 received glycopyrolate 200 micrograms i.v. followed by a bolus dose of remifentanil 1 microgram kg-1 over 30 s and an infusion of remifentanil at a rate of 0.5 microgram kg-1 min- 1. The other patients received remifentanil 0.5 microgram kg-1 over 30 s and an infusion of 0.25 microgram kg-1 min-1 with (group 2) or without (group 3) pretreatment with glycopyrrolate 200 micrograms. All patients then received a sleep dose of propofol, rocuronium 0.6 mg kg-1 and 1% isoflurane with 67% nitrous oxide in oxygen. Laryngoscopy and tracheal intubation were performed 3 min later. Heart rate and arterial pressure were recorded at 1-min intervals from before induction of anaesthesia until 5 min after intubation. Baseline heart rate was similar in all groups, but decreased in group 3 (no glycopyrrolate) after induction and remained significantly lower after intubation compared with the other groups (P < 0.05). Heart rate and arterial pressure increased slightly after intubation in each group but there were no significant differences in mean arterial pressure between groups at any time. The incidence of bradycardia (one patient in group 2) and hypotension (two patients in groups 1 and 2 and three patients in group 3) was low.      

Effects of olprinone hydrochloride after coronary artery bypass grafting

BACKGROUND: We have examined the effect of olprinone hydrochloride on hemodynamics and peripheral circulation after cardiopulmonary bypass (CPB) in 56 patients who underwent coronary artery bypass grfting. METHODS: The subjects were randomly classified into 2 groups: B-group of 25 patients who received bolus plus continuous administration of olprinone hydrochloride and control group without administration of olprinone hydrochloride (C-group) of 31 patients. In the B-group, after de-clamping of the aortic occlusion, olprinone hydrochloride 15 micrograms.kg-1 bolus was administered and followed by continuous administration at 0.1 microgram.kg-1.min-1. RESULTS: We excluded six cases in C-group in whom it was not possible to maintain blood pressure without olprinone hydrochloride. In the B-group, peripheral temperature was kept significantly higher and blood lactic acid value was kept significantly lower until 6 hours after the operation compared with C-group. In the B-group, cardiac index was kept significantly higher for a long period of time, and dosage of concomitantly used catecholamine could be significantly reduced. CONCLUSIONS: Olprinone increased CI and decreased SVRI, and it led to easy weaning from CPB, providing excellent hemodynamics after CABG. These results suggest that olprinone hydrochloride 15 micrograms.kg-1 bolus plus 0.1 microgram.kg-1.min-1 continuous administration may be effective for improvement of hemodynamics and peripheral circulation after CPB.