Benefits of a glucose-containing priming solution for cardiopulmonary bypass

Benefits from the use of glucose-containing intravenous and priming solutions during coronary artery bypass operation have not been documented, but an increased risk of postoperative neurologic deficit by hyperglycemia has been suggested. To determine benefits, 107 patients undergoing coronary artery bypass operation were managed identically except that one group (n = 54) received 5% dextrose in lactated Ringer's solution (D5LR) as the sole intravenous and priming solution during operation and a second group (n = 53) received the same solution without glucose (LR). During cardiopulmonary bypass, the D5LR group required significantly less additional crystalloid to maintain safe oxygenator levels and flow (1.8 +/- 3.3 vs 15.8 +/- 20.9 mL.kg-1.h-1) and produced more urine (3.5 +/- 3.2 vs 1.2 +/- 1.4 mL.kg-1.h-1). By 24 h after operation, fluid balance in the LR group was approximately 2 L more positive than in the D5LR group. Five days after operation, the D5LR group weighed less than preoperatively (-0.8 +/- 2.6 kg), whereas the LR group gained weight (+1.0 +/- 2.8 kg). We conclude that use of glucose-containing solutions during coronary artery bypass operation benefits patients by decreasing perioperative fluid requirements and postoperative fluid retention. Because embolism is the cause of most postoperative neurologic deficits, any increased risk by hyperglycemia is small.     

A prospective randomized study of hydroxyethyl starch, albumin, and lactated Ringer's solution as priming fluid for cardiopulmonary bypass

The ideal priming fluid for cardiopulmonary bypass is not known. We designed a study to determine whether there are important differences in the clinical effects of hydroxyethyl starch versus albumin when used in priming fluid, and in the clinical effects of colloid versus crystalloid priming fluid. We prospectively randomized 83 adult patients undergoing coronary artery bypass or valve replacement. All patients were managed by standardized protocol, and they received one of three priming fluids for bypass: hydroxyethyl starch (HES), 26 patients; albumin (ALB), 28 patients, and lactated Ringer's solution (LRS), 29 patients. The groups were stratified by body weight and type of operation. We measured 41 variables relating to operative time factors, fluid balance, bleeding, and organ function (renal, cardiac, and pulmonary) at several time intervals. The LRS group had a significantly lower colloid osmotic pressure than the other two groups, and the HES group had a substantially higher blood viscosity. Although the prothrombin time was significantly lower in the LRS group (p less than 0.05), the differences were very small and not clinically important. The platelet count in the HES group was significantly lower than in the other two groups immediately after bypass, but it was not different by the time the patients left the operating room. There were no differences among the groups in chest tube drainage, blood bank usage, or fluid balance. Postoperatively, the pulmonary shunt fraction was significantly greater in the LRS group. Body weight increased more in the LRS than in the HES and ALB groups (p = 0.01). No adverse reaction to the prime solutions was noted. The differences between the HES and ALB groups--prothrombin time, platelet count, and blood viscosity--had no apparent clinical effects; thus, the two may be considered clinically equivalent. The greater somatic and pulmonary fluid accumulation in the LRS group suggests that colloid is preferable to crystalloid in priming fluid.     

Mannitol and dopamine in patients undergoing cardiopulmonary bypass: a randomized clinical trial

In this prospective, randomized, placebo-controlled, double-blinded study, we determined the effects of two commonly used adjuncts, mannitol and dopamine, on beta(2)-microglobulin (beta(2)M) excretion rates in patients undergoing coronary artery bypass graft surgery with cardiopulmonary bypass (CPB). beta(2)M excretion rate has been described as a sensitive marker of proximal renal tubular function. One-hundred patients with a preoperative serum creatinine level 相似文献   

Hydroxyethyl starch as a priming solution for cardiopulmonary bypass impairs hemostasis after cardiac surgery

We investigated the influence of hydroxyethyl starch (HES) as a priming solution for the cardiopulmonary bypass (CPB) circuit on postoperative hemostasis in 45 patients undergoing elective coronary artery bypass grafting. In a randomized sequence, 20 mL/kg of low-molecular-weight HES (HES 120; molecular weight 120,000 daltons), high-molecular-weight HES (HES 400; molecular weight 400,000 daltons), or 4% human albumin (ALB) was used as the main component of the CPB priming solution. The thromboelastographic values indicating the speed of solid clot formation (alpha-angle) and the strength of the fibrin clot (maximum amplitude and shear elastic modulus) were decreased up to 2 h after CPB in both HES groups. Four hours after the operation, blood loss through the chest tubes had increased in the HES groups: HES 120, mean 804 mL (range, 330-1390 mL); HES 400, mean 1008 mL (range, 505-1955 mL); and ALB, mean 681 mL (range, 295-1500 mL) (P < 0.05 between the HES 400 and ALB groups). We conclude that HES solutions, when given in doses of 20 mL/kg in connection with the CPB prime, compromise hemostasis after cardiac surgery. This effect appears related to formation of a less stable thrombus compared with that formed in the presence of ALB. IMPLICATIONS: The influence of hydroxyethyl starch (HES) on postoperative hemostasis was investigated in cardiac surgery. The thromboelastographic values indicated that HES solutions, when given in connection with the cardiopulmonary bypass prime, compromise hemostasis after cardiac surgery. This effect seems to occur through the formation of a less stable clot.     

Hydroxyethyl starch versus Ringer solution in cardiopulmonary bypass prime solutions (a randomized controlled trial)

Background  

In our study we compared the Ringer solution, which is the standard prime solution of our department, with the HES (Hydroxyethyl starch) 130-0.4 solution, which can be a potential alternative prime solution with an indispensable material for the cardio-pulmonary bypass applications.     

A double-blind randomized trial: prophylactic vasopressin reduces hypotension after cardiopulmonary bypass

BACKGROUND: Inhibition of angiotensin-converting enzyme (ACE) predisposes patients to vasodilatory hypotension after cardiopulmonary bypass (CPB). This hypotension has been correlated with arginine vasopressin deficiency and can be corrected by its replacement. In patients receiving ACE inhibition, we investigated whether initiation of vasopressin before CPB would diminish post-CPB hypotension and catecholamine use by avoiding vasopressin deficiency. METHODS: Cardiac surgical patients on ACE inhibitor therapy were randomized to receive vasopressin (0.03 U/min) (n = 13) or an equal volume of normal saline (n = 14) starting 20 minutes before CPB. RESULTS: Vasopressin did not change pre-CPB mean arterial pressure or pulmonary artery pressure. After CPB, the vasopressin group had a lower peak norepinephrine dose than the placebo group (4.6 +/- 2.5 versus 7.3 +/- 3.5 microg/min, p = 0.03), a shorter period on catecholamines (5 +/- 6 versus 11 +/- 7 hours, p = 0.03), fewer hypotensive episodes (1 +/- 1 versus 4 +/- 2, p < 0.01), and a shorter intensive care unit length of stay (1.2 +/- 0.4 versus 2.1 +/- 1.4 days, p = 0.03). CONCLUSIONS: In this cohort, prophylactic administration of vasopressin, at a dose without a vasopressor effect pre-CPB, reduced post-CPB hypotension and vasoconstrictor requirements, and was associated with a shorter intensive care unit stay.     

Ischemic preconditioning in deceased donor liver transplantation: a prospective randomized clinical trial of safety and efficacy.

Ischemic preconditioning (IPC) has the potential to decrease graft injury and morbidity after liver transplantation. We prospectively investigated the safety and efficacy of 5 minutes of IPC induced by hilar clamping in local deceased donor livers randomized 1:1 to standard (STD) recovery (N = 28) or IPC (N = 34). Safety was assessed by measurement of heart rate, blood pressure, and visual inspection of abdominal organs during recovery, and efficacy by recipient aminotransferases (aspartate aminotransferase [AST] and alanine aminotransferase [ALT], both measured in U/L), total bilirubin, and international normalized ratio of prothrombin time (INR) after transplantation. IPC performed soon after laparotomy did not cause hemodynamic instability or visceral congestion. Recipient median AST, median ALT, and mean INR, in STD vs. IPC were as follows: day 1 AST 696 vs. 841 U/L; day 3 AST 183 vs. 183 U/L; day 1 ALT 444 vs. 764 U/L; day 3 ALT 421 vs. 463 U/L; day 1 INR 1.7 +/- .4 vs. 2.0 +/- .8; and day 3 INR 1.3 +/- .2 vs. 1.4 +/- .3; all P > .05. No instances of nonfunction occurred. The 6-month graft and patient survival STD vs. IPC were 82 vs. 91% and median hospital stay was 10 vs. 8 days; both P > .05. In conclusion, deceased donor livers tolerated 5 minutes of hilar clamping well, but IPC did not decrease graft injury. Further trials with longer periods of preconditioning such as 10 minutes are needed.     

Colloids versus crystalloids as priming solutions for cardiopulmonary bypass: a meta-analysis of prospective, randomised clinical trials

Using Cochrane methodology a review was performed of prospective randomized clinical trials comparing colloidal pump priming solutions for cardiopulmonary bypass. Dextrans were not considered. Database searches from 1966 through December 2002 delivered 265 articles. Seventeen studies finally met the eligibility criteria involving 997 patients. Summary odds ratio estimates from the 5 studies reporting mortality were 1.46 (n = 326; 95%-Confidence-Interval: .55 to 3.85; p = .49) for crystalloids against colloids and .74 (n = 150; 95%-Confidence-Interval: .17 to 3.36; p = .49) for albumin versus synthetic colloids. Most commonly used outcome measures further included postoperative blood loss, platelet-count, fluid-balance and, colloid osmotic pressures from which Standardized Mean Differences (SMD) and their 95%-Confidence-Interval (95%CI) were extracted. Colloids produced significantly higher oncotic pressures and less positive fluid-balances. Although across 9 studies postoperative bleeding between colloids and crystalloids did not differ (n = 663; SMD: -.03, 95%CI: -.18 to .12; p = .69), platelet counts significantly favoured crystalloids (n = 465; SMD: -.42; 95%CI: -.68 to -.16; p = .00). However, compared to albumin platelet counts were significantly disfavoured only by starches (n = 321; SMD: -.55; 95%CI: -.77 to -.32; p = .00). To conclude, using mere crystalloids produced more pronounced positive fluid balances and their avoidance as a single pump-prime component can be suggested. Since albumin is not necessarily associated with better outcomes and is more expensive, it is hard to continue its use. However, there is still insufficient evidence available to allow definitive conclusions.     

Coronary artery bypass grafting supported with intracardiac microaxial pumps versus normothermic cardiopulmonary bypass: a prospective randomized trial.

OBJECTIVE: To analyze the difference in coronary artery bypass grafting (CABG) performed with normothermic cardiopulmonary bypass (CPB) and CABG supported with the intracardiac microaxial pump (ICP, Impella, Aachen, Germany). METHODS: A prospective randomized study was conducted in seven centers. The study population consists of 199 patients undergoing isolated primary CABG (CPB group 94 patients, ICP group 105 patients). Both groups are equal in demographic variables, number of bypasses performed, and Euroscore predicted mortality. We analyzed clinical outcome, myocardial enzymes and blood parameters of hemolysis, organ function and inflammatory response. RESULTS: Seventeen patients (16%), randomized in the ICP group, were switched to the CPB group. This was due to the inability to position the right side catheter adequately (n=8), to a pump failure (n=1) or to the perioperative decision that beating heart surgery is technically not possible (n=8). There was no significant difference between the two study arms regarding the pump assistance time (CPB 67.1+/-22.9 min; ICP 67.7+/-30.3 min; P=0.88861), the number of grafts (CPB 2.4+/-0.7; ICP 2.3+/-0.8) and the number of grafts to the back wall (CFX; both groups n=37). There is no significant difference in clinical outcome, evolution of myocardial enzymes, indices of organ function and hemolysis. There is a reduced inflammatory response in the ICP group as indicated in the postoperative release of granulocyte elastase (CPB 259+/-195; ICP 150+/-126 microg/l; P<0.00001) and complement C3 (CPB 0.73+/-0.2; ICP 0.65+/-0.2g/l; P=0.008). CONCLUSION: The intracardiac pump for the right heart is difficult to introduce. As a consequence the right side pump underwent design modifications. There were no differences in clinical outcome between both groups. The inflammatory response is significantly reduced in the ICP group.     

Mechanical ventilation affects inflammatory mediators in patients undergoing cardiopulmonary bypass for cardiac surgery: a randomized clinical trial

OBJECTIVES: Respiratory support for patients recovering from cardiopulmonary bypass and cardiac surgery uses large tidal volumes and a minimal level of positive end-expiratory pressure. Recent data indicate that these ventilator settings might cause pulmonary and systemic inflammation in patients with acute lung injury. We examined the hypothesis that high tidal volumes and low levels of positive end-expiratory pressure might worsen the inflammatory response associated to cardiopulmonary bypass. METHODS: Forty patients undergoing elective coronary artery bypass were randomized to be ventilated after cardiopulmonary bypass disconnection with high tidal volume/low positive end-expiratory pressure (10-12 mL/kg and 2-3 cm H2O, respectively) or low tidal volume/high positive end-expiratory pressure (8 mL/kg and 10 cm H2O, respectively). Interleukin 6 and interleukin 8 levels were measured in the bronchoalveolar lavage fluid and plasma. Samples were taken before sternotomy (time 0), immediately after cardiopulmonary bypass separation (time 1), and after 6 hours of mechanical ventilation (time 2). RESULTS: Interleukin 6 and interleukin 8 levels in the bronchoalveolar lavage fluid and plasma significantly increased at time 1 in both groups but further increased at time 2 only in patients ventilated with high tidal volume/low positive end-expiratory pressure. Interleukin 6 and interleukin 8 levels in the bronchoalveolar lavage fluid and in the plasma at time 2 were higher with high tidal volume/low positive end-expiratory pressure than with low tidal volume/high positive end-expiratory pressure. CONCLUSION: Mechanical ventilation might be a cofactor able to influence the inflammatory response after cardiac surgery.     

Retrograde autologous priming of the cardiopulmonary bypass circuit: safety and impact on postoperative outcomes

OBJECTIVES: Retrograde autologous priming (RAP) is a blood conservation technique used to limit the severity of hemodilution during cardiopulmonary bypass and reduce perioperative transfusions. The aim of this investigation was to examine the safety of RAP and to determine the effect of RAP on adverse outcomes after cardiac surgery. DESIGN: Retrospective cohort study. SETTING: University hospital. PARTICIPANTS: Five hundred fifty-nine undergoing cardiopulmonary bypass. INTERVENTIONS: Data were retrospectively collected on 2 cohorts of adult cardiac surgical patients operated on by a single surgeon. In the RAP group (n = 256), outcome data were analyzed on all subjects over a 2-year period during which RAP was used routinely. This group was compared with a similar cohort of patients undergoing cardiopulmonary bypass over a 2-year period immediately before the introduction of RAP into the clinical practice (no-RAP group, n = 287). MEASUREMENTS AND MAIN RESULTS: In-hospital mortality was not significantly different between the RAP group (2.7%) and the no-RAP group (3.8%, p = 0.636). The incidence of postoperative cardiac arrest was significantly less in the RAP group (1 patient) compared to the no-RAP group (9 patients, p = 0.040). There were no differences between the 2 groups in the incidence of several other postoperative complications, including postoperative delirium (1.6% RAP v 3.1% no RAP), heart block (1.6% RAP v 4.2% no RAP), atrial fibrillation (19.1% RAP v 22.7% no RAP), and requiring postoperative ventilation >24 hours (2.7% RAP v 5.2% no RAP). CONCLUSIONS: The authors observed no evidence of any increase in adverse events in the RAP group of this retrospective cohort study, but they did observe a decrease in the incidence of postoperative cardiac arrest in the RAP group. These findings suggest that RAP is a safe technique and may have a beneficial effect on postoperative outcomes.