Pharmacological strategies to decrease excessive blood loss in cardiac surgery: a meta-analysis of clinically relevant endpoints

High-affinity block of voltage-operated rat IIA neuronal sodium channels by 2,6 di-tert-butylphenol, a propofol analogue

BACKGROUND AND OBJECTIVE

Propofol is a phenol derivative (2,6 di-isopropylphenol) with a unique effect profile including activating effects on GABA(A) and blocking effects on voltage-operated sodium channels. If the substituents in the 2- and the 6-positions are replaced by tert-butyl groups, the resulting phenol derivative, 2,6 di-tert-butylphenol, despite being a close structural propofol analogue, completely lacks GABA(A) receptor effects. The aim of this in vitro study was to investigate the effects of 2,6 di-tert-butylphenol on voltage-operated neuronal sodium channels in order to determine whether and, if so, how these structural changes alter the sodium channel-blocking effect seen with propofol.

METHODS

Whole-cell sodium inward currents through heterologously expressed rat type IIA sodium channels were recorded in the absence and presence of definite concentrations of 2,6 di-tert-butylphenol and propofol.

RESULTS

When applied at concentrations > or = 30 micromol, 2,6 di-tert-butylphenol completely and irreversibly blocked sodium inward currents. The blockade equilibrium time was about 2 min. A partial washout was possible only if the application was stopped before the equilibrium of the blockade was achieved.

CONCLUSIONS

2,6 Di-tert-butylphenol exerts a high-affinity block of neuronal sodium channels. Apparently, the slight structural differences of 2,6 di-tert-butylphenol in comparison with propofol--which account for the lack of GABA(A) receptor effects--enhance its voltage-operated sodium channel-blocking effects. As 2,6 di-tert-butylphenol is much more potent than most sodium channel blockers in clinical use, it might be of interest in the development of local anaesthetics.

Effects of rolipram, pimobendan and zaprinast on ischaemia-induced dysrhythmias and on ventricular cyclic nucleotide content in the anaesthetized rat

BACKGROUND AND OBJECTIVE

This study was designed to compare the haemodynamic, electrophysiological and pharmacodynamic effects of three selective inhibitors of the different isoenzyme forms of phosphodiesterase (PDE) on ischaemia-induced dysrhythmias in the anaesthetized rat. The drugs used were pimobendan, a selective PDE III inhibitor, rolipram, a selective PDE IV inhibitor, and zaprinast, a selective PDE V inhibitor.

METHODS

The coronary artery was occluded 15 min after commencing drug administration, and myocardial ischaemia was maintained for 30 min during which the heart rate and mean arterial pressure were recorded. cAMP and cGMP were determined by radioimmunoassay.

RESULTS

Pretreatment with rolipram decreased the duration of ventricular tachycardia without any change in the incidences of dysrhythmias or the mortality rate. This drug did not modify ventricular content of adenosine 3',5'-cyclic monophosphate (cAMP) or guanosine 3',5'-cyclic monophosphate (cGMP). Pimobendan (1 mg kg(-1) + 0.1 mg kg(-1) min) decreased the duration of ventricular tachycardia. This dose of pimobendan and zaprinast (1 mg kg(-1) + 0.1 mg kg(-1) min(-1)) increased the incidence rate of ventricular fibrillation following coronary artery ligation and the mortality rate. Moreover, both drugs increased cGMP in the ventricle.

CONCLUSIONS

The results demonstrated that pimobendan and zaprinast increased the incidence of dysrhythmias and the mortality rate, which was accompanied by an increase in the ventricular content of cGMP. Rolipram decreased the duration of ventricular tachycardia without a change in the cyclic nucleotide content or in the mortality rate.

Fibrinolytic activity and bleeding after cardiac surgery with cardiopulmonary bypass and low-dose aprotinin therapy

Low-dose aprotinin inhibits hyperfibrinolysis in cardiac surgery. However, excessive postoperative bleeding and increased fibrinolysis may occur despite low dose-aprotinin administration. We investigated (i) whether fibrinolytic activity significantly rises under low-dose aprotinin administration, and (ii) whether this is associated with excessive postoperative bleeding (> or = 1000 ml/24 h). In a prospective single-blind trial, 120 consecutive patients were randomized to receive 280 mg aprotinin or no aprotinin before skin incision. D-dimer levels increased significantly to the end of surgery, reaching higher levels in the control group. The risk for excessive bleeding was lower in the aprotinin group (12 versus 37%, = 0.001). Fifteen minutes after heparin reversal, patients were at risk for excessive bleeding, when enhanced fibrinolysis was documented (aprotinin group, D-dimer > or = 1.0 micro g/ml, odds ratio = 9.1, = 0.047; control group, D-dimer > or = 3.0 micro g/ml, odds ratio = 4.6, = 0.014). Ninety-seven per cent of the aprotinin group and 81% of control group patients had no excessive bleeding when the D-dimer plasma level was below these values. We conclude that (i) fibrinolytic activity significantly rises under low-dose aprotinin administration, and (ii) plasma D-dimer levels at end of surgery may help to identify patients who are unlikely to develop excessive postoperative bleeding.

High-dose aprotinin reduces activation of hemostasis, allogeneic blood requirement, and duration of postoperative ventilation in pediatric cardiac surgery

BACKGROUND

Though multiple studies have affirmed the effectiveness of aprotinin in reducing blood loss in adult cardiac surgery, the possible benefit in pediatric cardiac surgery is controversial.

METHODS

In a double-blind, randomized, and placebo-controlled study, the efficacy of aprotinin in attenuating the hemostatic and inflammatory activation during cardiopulmonary bypass in 60 patients weighing less than 10 kg was investigated. Secondary endpoints were the influence of aprotinin on the reduction of blood loss and allogeneic blood requirement, as well as postoperative oxygenation and length of mechanical ventilation. Aprotinin was administered in a high-dose of 3 x 10(4) KIU/kg plus a bolus of 5 x 10(5) KIU (not weight adjusted) added to the pump prime.

RESULTS

Aprotinin plasma concentration at the end of cardiopulmonary bypass (CPB) was with 184 +/- 45 KIU/mL, within the targeted range of 200 KIU/mL. Coagulation and fibrinolysis were suppressed (F1.2 1 hour after CPB: 5.35 +/- 2.9 nmol/L vs 14.5 +/- 23.1 nmol/L; D-dimer 1 hour after CPB: 0.63 +/- 0.6 ng/mL vs 2.3 +/- 3.1 ng/mL; p < 0.05), inflammatory markers (interleukin [IL]-6, IL-8, IL-10) increased over time without significant differences between the groups, and only complement C3a activation was significantly attenuated at the end of CPB in the aprotinin group. Chest tube drainage was significantly reduced (24 hours: median 13.5 [IQR 12.2] mL/kg vs 19.4 [8.2] mL/kg; p < 0.05). All patients received one unit of packed cells to prime the heart lung machine. A second unit was needed significantly less often in the aprotinin group (13% vs 47%; p < 0.05). Postoperative oxygenation (pO2/FIO2 172 [IQR 128] mm Hg vs 127 [74]; p < 0.05) improved, and the time on ventilator was shorter in the aprotinin group (median 45 hours [IQR 94] vs 101 [IQR 74]; p < 0.05). No side effects were attributable to the use of aprotinin.

CONCLUSIONS

High-dose aprotinin effectively attenuated hemostatic activation and reduced blood loss and transfusion requirement in pediatric cardiac surgery. Postoperative ventilation was also shortened in the aprotinin group.

The predictive value of modified computerized thromboelastography and platelet function analysis for postoperative blood loss in routine cardiac surgery

Hemorrhage after cardiopulmonary bypass (CPB) remains a clinical problem. Point-of-care tests to identify hemostatic disturbances at the bedside are desirable. In the present study, we evaluated the predictive value of two point-of-care tests on postoperative bleeding after routine cardiac surgery. Prospectively, 255 consecutive patients were studied to compare the ability of modified thromboelastography (ROTEG) as well as a platelet function analyzer (PFA-100) to predict postoperative blood loss. Measurements were performed at three time points: preoperatively, during CPB, and after protamine administration with three modified thromboelastography and PFA tests. The best predictors of increased bleeding tendency were the tests performed after CPB. The angle alpha is the best predictor (area under the receiver operating characteristic curve 0.69) and, in combination with the adenosine diphosphate-PFA test, the predictive accuracy is enhanced (area under the receiver operating characteristic curve 0.73). The negative predictive value for the angle alpha is 82%, although the positive predictive value is small (41%). Thromboelastography is a better predictor than PFA. In routine cardiac surgery, impaired hemostasis as identified by point-of-care tests does not inevitably lead to hemorrhage postoperatively. However, patients with normal test results are unlikely to bleed for hemostatic reasons. Bleeding in these patients is probably caused surgically. The high negative predictive value supports early identification and targeted treatment of surgical bleeding by distinguishing it from a significant coagulopathy.

IMPLICATIONS

Thrombelastography and platelet function analysis in routine cardiac surgery demonstrate high negative predictive values for postoperative bleeding, which supports early identification and targeted treatment of surgical bleeding by distinguishing it from a significant coagulopathy. The positive predictive values are small. The best predictors are thrombelastography values obtained after cardiopulmonary bypass.

The predictive value of modified computerized thromboelastography and platelet function analysis for postoperative blood loss in routine cardiac surgery

Hemorrhage after cardiopulmonary bypass (CPB) remains a clinical problem. Point-of-care tests to identify hemostatic disturbances at the bedside are desirable. In the present study, we evaluated the predictive value of two point-of-care tests on postoperative bleeding after routine cardiac surgery. Prospectively, 255 consecutive patients were studied to compare the ability of modified thromboelastography (ROTEG) as well as a platelet function analyzer (PFA-100) to predict postoperative blood loss. Measurements were performed at three time points: preoperatively, during CPB, and after protamine administration with three modified thromboelastography and PFA tests. The best predictors of increased bleeding tendency were the tests performed after CPB. The angle alpha is the best predictor (area under the receiver operating characteristic curve 0.69) and, in combination with the adenosine diphosphate-PFA test, the predictive accuracy is enhanced (area under the receiver operating characteristic curve 0.73). The negative predictive value for the angle alpha is 82%, although the positive predictive value is small (41%). Thromboelastography is a better predictor than PFA. In routine cardiac surgery, impaired hemostasis as identified by point-of-care tests does not inevitably lead to hemorrhage postoperatively. However, patients with normal test results are unlikely to bleed for hemostatic reasons. Bleeding in these patients is probably caused surgically. The high negative predictive value supports early identification and targeted treatment of surgical bleeding by distinguishing it from a significant coagulopathy.

IMPLICATIONS

Thrombelastography and platelet function analysis in routine cardiac surgery demonstrate high negative predictive values for postoperative bleeding, which supports early identification and targeted treatment of surgical bleeding by distinguishing it from a significant coagulopathy. The positive predictive values are small. The best predictors are thrombelastography values obtained after cardiopulmonary bypass.

Cost comparisons of pharmacological strategies in open-heart surgery

Open-heart surgery (OHS) is performed to bypass occluded arteries, replace malfunctioning cardiac valves or correct congenital abnormalities. The average cost of OHS varies from $US25 057-$US79 795 (1997 values). The objective of this paper was to review economic studies of pharmacological strategies in open-heart surgery. Pharmacological strategies studied include the prevention of postoperative complications such as atrial fibrillation (AF), bleeding and infection. Modifications in anaesthetic technique have been attempted by using agents that promote early extubation. In addition, strategies for postoperative management of sedation, analgesia and AF and use of neuromuscular blockers have also been compared. The majority of studies in this area have been cost analyses with few cost-effectiveness studies performed. Prophylaxis against AF with amiodarone is associated with a reduction in AF and was cost-neutral compared with placebo. Compared with placebo, prevention of bleeding with antifibrinolytics reduces transfusion costs. In direct comparative studies, lysine analogues, due to lower drug acquisition costs, offset transfusion costs to a greater extent than aprotinin. However, safety concerns with the lysine analogues remain. Erythropoietin decreases transfusion requirements and is cost effective compared with no intervention when the cost of postoperative bacterial complications is included. First- and second-generation cephalosporins prevent postoperative infections. Based on drug acquisition cost, the first-generation agents are less expensive although when administration costs are included, both classes have similar costs. Modifications in anaesthetic technique with short-acting anaesthetic agents, results in higher drug costs although nursing and total hospital costs are typically reduced. For neuromuscular blockers, drug acquisition costs are lowest with pancuronium but administration costs and the cost of adverse events have not been included in existing analyses. Midazolam provides an equivalent level of postoperative sedation to propofol but the acquisition cost is lower. The combined use of propofol and midazolam warrants further investigation, as its use is associated with lower sedative agent costs compared with either agent alone. There is limited data on the economics of postoperative analgesia and the management of AF. As the majority of studies to date are partial cost analyses, additional studies that include length of stay and other hospitalisation data are warranted. In future, cost-effectiveness and cost-utility studies, which incorporate quality of life and the cost of adverse effects and other longer term costs, should be undertaken.

Pharmacological approaches to reducing allogeneic blood exposure

This article discusses evidence for the role of pharmacological interventions such as the protease inhibitor aprotinin (Trasylol), lysine analogue anti-fibrinolytics [tranexamic acid (Cyclokapron) and epsilon aminocaproic acid (Amicar)], DDAVP (Desmopressin) and recombinant Factor VIIa (NovoSeven), in preventing the need for blood and blood-component therapies after major (cardiac, hepatic and orthopaedic/trauma) surgery. The data show that aprotinin is consistently effective in reducing globally the transfusion burden in cardiac and hepatic surgical procedures. However, there are little data to support its use in routine elective orthopaedic surgery. Multiple studies have failed to show an increased risk for myocardial ischaemia or infarction with aprotinin, and there may even be a reduced incidence of perioperative stroke in patients undergoing cardiac surgery. An increased probability of a hypersensitivity reaction when the drug is readministered within a 6-month period remains a significant issue. The data for the lysine analogue anti-fibrinolytics show no evidence of efficacy in reducing the transfusion burden for epsilon aminocaproic acid and inconsistent results with tranexamic acid in cardiac and hepatic surgery. As with aprotinin therapy, there is a paucity of data to support their use in routine elective orthopaedic surgery. There are no data to support the routine use of DDAVP to reduce the transfusion burden. Limited data suggest that this drug may be effective when a defect in platelet function is demonstrated. This aspect deserves further investigation. Recombinant activated Factor VII (rFVIIa) has proven benefit for its licensed indication to reduce bleeding in haemophiliacs with inhibitors to Factors VIII and IX. Reports of benefit in other instances are largely anecdotal. Hence, at this time it is therefore speculative and premature to suggest whether there is a place for this agent in routine clinical practice. No adequately powered, placebo-controlled prospective studies are available to investigate the safety of the lysine analogues, DDAVP or rFVIIa in cardiac, hepatic or orthopaedic surgery.

Effect of blood transfusion on long-term survival after cardiac operation

BACKGROUND

Blood transfusions have been linked to increased morbidity and mortality. Bleeding during and after cardiac operations and the hemodilution effects of cardiopulmonary bypass commonly result in blood transfusions. Because we could not find any studies evaluating the effects of transfusion on long-term survival after cardiac operation, we sought to determine these effects.

METHODS

We studied 1,915 patients who underwent first-time isolated coronary artery bypass operations between July 6, 1994 and December 31, 1997 at our institution. Patients with transfusions were compared with those who had not been transfused. Long-term survival data were obtained from the United States Social Security Death Index. Groups were compared by Cox proportional hazard models, Kaplan-Meier survival plots, and hazard functions.

RESULTS

Six hundred forty-nine of 1,915 study patients (34%) received a transfusion during their hospitalization. Transfused patients were older, smaller, and more likely to be female, and had more comorbidity. Transfused patients also had twice the 5-year mortality (15% vs 7%) of nontransfused patients. After correction for comorbidities and other factors, transfusion was still associated with a 70% increase in mortality (risk ratio = 1.7; 95% confidence interval = 1.4 to 2.0; p = 0.001). By multivariate analysis, transfusion, peripheral vascular disease, chronic obstructive pulmonary disease, New York Heart Association functional class IV, and age were significant predictors of long-term mortality.

CONCLUSIONS

We found that blood transfusions during or after coronary artery bypass operations were associated with increased long-term mortality.

A model of the direct and indirect effects of aprotinin administration on the overall costs of coronary revascularization surgery in a university teaching hospital cardiothoracic unit

BACKGROUND

Cardiac patients sometimes bleed postoperatively and consequently require rethoracotomy, necessitating a longer stay in the intensive care unit (ICU) of the cardiothoracic unit (CTU). When ICU capacity is limited, rethoracotomy necessitates postponing treatment of the next patient. Aprotinin, a bovine lung-derived proteinase inhibitor, has been shown to reduce the frequency of rethoracotomies in cardiac patients.

OBJECTIVE

This study was undertaken to quantify the reduction of potentially avoidable cost to the CTU of postoperative bleeding, both directly and indirectly, by administering aprotinin before and during coronary artery bypass graft (CABG).

METHODS

A novel, validated operational research model was developed, featuring the principal CABG-related health care resource parameters believed to influence waiting lists and times. Factors and costs were derived from both local data from a CTU and relevant recent literature.

RESULTS

According to the model, aprotinin therapy reduced the waiting list by approximately 3% by reducing the number of rethoracotomies. Using data from the literature, for an annual throughput of 431 patients who would receive aprotinin costing 97,333 pounds per year, the annual net savings to the CTU would be 46,586 pounds, which comprised direct savings on blood products of 35,036 pounds and indirect marginal savings of 11,550 pounds derived from 3.2% fewer rethoracotomies (each at a marginal cost of 837 pounds). By reason, then, reinvesting savings in increasing CTU capacity would yield further waiting-list reductions and improve patient morbidity. These results had 2 major limitations. First, it was assumed that all operations would have the same duration and all surgeons would perform operations in the same manner. Second, nonurgent patients were assumed to have been treated in order of strict referral sequence, which may not be done in real-world practice.

CONCLUSIONS

Aprotinin reduced costs in CABG directly by reducing the use of blood products and indirectly by reducing waiting lists, as well as by reducing morbidity and mortality associated with waiting time.

Management of bleeding disorders by prohemostatic therapy

Pro-hemostatic therapy aims at an improvement of hemostasis, which may be achieved by amelioration of primary hemostasis, stimulation of fibrin formation or inhibition of fibrinolysis. These treatment strategies may be applied to specifically correct a defect in one of the pathways of coagulation, but have in some situations also been shown to be effective in reducing bleeding in patients without a primary defect in coagulation. Besides the transfusion of platelets in case of thrombocytopenia or severe platelet disorders, a pharmacological improvement of primary hemostasis may be achieved by the administration of desmopressin. The administration of DDAVP results in a marked increase in the plasma concentration of Von Willebrand factor (and associated coagulation factor VIII) and (also by yet unexplained additional mechanisms) a remarkable potentiation of primary hemostasis as a consequence. DDAVP is used for the prevention and treatment of bleeding in patients with von Willebrand disease or mild hemophilia A, and further in patients with an impaired function of primary hemostasis, such as in patients with uremia, liver cirrhosis or in patients with aspirin-associated bleeding. Based on the current insight that activation of coagulation in vivo predominantly proceeds by the tissue factor/factor VII(a) pathway, recombinant factor VIIa has been developed as a prohemostatic agent and has recently become available for clinical use. Indeed, in uncontrolled clinical studies this compound has been shown to exert a potent procoagulant activity and appeared to be highly effective in the prevention and treatment of bleeding, although most experience so far has been obtained in patients with severe and complicated coagulation defects. At present, a more general use of this agent for bleeding patients without an apparent coagulation defect is the subject of a number of ongoing clinical trials. Agents that exert anti-fibrinolytic activity are aprotinin and the group of lysine analogues. The pro-hemostatic effect of these agents proceeds not only by the inhibition of fibrinolysis (thereby shifting the procoagulant/anticoagulant balance towards a more procoagulant state), but also due to a protective effect on platelets, as has been demonstrated at least for aprotinin. The mechanism of this platelet-protective effect has, besides a potential prevention of plasmin-mediated loss of platelet receptors not been elucidated. Whether the pro-hemostatic effect of the anti-fibrinolytic agents will eventually result in a higher incidence of thromboembolic complications is still a matter of debate (see further), however, this has so far not been shown in straightforward clinical trials.

Hemostatic effects of tranexamic acid in elective thoracic aortic surgery: a prospective, randomized, double-blind, placebo-controlled study

OBJECTIVE

We studied the hemostatic effects of tranexamic acid in patients undergoing elective surgery involving the thoracic aorta.

METHODS

In a double-blind, randomized fashion, 60 consecutive patients were assigned to two treatment groups: 30 patients (placebo group) received infusion of saline solution, and 30 (treatment group) received tranexamic acid (1 g before skin incision, an infusion of 400 mg/h during the operation, and 500 mg in the pump priming). Perioperative bleeding was considered as a primary outcome. Perioperative allogeneic transfusions, major thrombotic complications (myocardial infarction, pulmonary embolism, renal insufficiency), and surgical outcomes were also considered.

RESULTS

Patients treated with tranexamic acid showed significant reductions in postoperative bleeding, both in terms of the amount collected during the first 4 postoperative hours (median 307 mL, interquartile range 253-361 mL in the placebo group vs median 211 mL, interquartile range 108-252 mL in the treatment group, P =.002) and in terms of total bleeding (median 722 mL, interquartile range 574-952 mL in the placebo group vs median 411 mL, interquartile range 313-804 mL in the treatment group, P =.04). Consequently, the number of patients transfused differed significantly between groups (21 patients [72.4%] in the placebo group vs 13 [44.8%] in the treatment group, P =.033). Patients in the treatment group showed significant reductions in the total amount for the entire group of packed red cells transfused (13,500 mL in the treatment group vs 28,000 mL in the placebo group, P =.012) and in the total amount of allogeneic transfusions (23,400 mL in the treatment group vs 53,000 mL in the placebo group, P =.024). No differences in perioperative thrombotic complications were found.

CONCLUSIONS

In this initial series of patients undergoing thoracic aortic surgery, tranexamic acid appeared effective in reducing perioperative bleeding, with a significant reduction in the need for allogeneic transfusions and without any increased risk of thrombotic complications.

Multidisciplinary management of a Jehovah's Witness patient for the removal of a renal cell carcinoma extending into the right atrium

PURPOSE

To highlight the management of a Jehovah's witness surgical patient presenting for cardiopulmonary bypass (CPB) and deep hypothermic circulatory arrest.

CLINICAL FEATURES

A 47-yr-old male, Jehovah's Witness, with renal cell carcinoma was admitted for left radical nephrectomy and excision of tumour thrombus extending into the junction of the inferior vena cava (IVC) and right atrium (RA). The preoperative goals were to maximize red blood cell mass, delineate the extent of tumour extension and develop a surgical plan incorporating blood conservation strategies to minimize blood loss. A midline abdominal incision was made to optimize removal of the non-caval portion of the tumour from the intra-abdominal region. CPB and deep hypothermic circulatory arrest were instituted to aid in removing the tumour from the IVC and RA. Intraoperative blood conservation strategies included the use of acute normovolemic hemodilution, antifibrinolytics, cell salvage, point-of-care monitoring of heparin and protamine blood concentrations, leukocyte-depleting filter, and meticulous surgical techniques. The patient was successfully weaned from CPB and was transported to the cardiothoracic intensive care unit without complication. The patient was discharged home one week after the operation with a hemoglobin of 10.2 g x dL(-1) and a hematocrit of 31.2%.

CONCLUSION

Multiple blood conservation techniques were employed to manage this Jehovah's Witness patient through complex cardiac surgery, which was previously denied to him at other institutions. The successful outcome of this patient, while respecting the right to refuse allogeneic blood products, is a result of a multidisciplinary collaboration as well as the application of established blood conservation techniques.

Hyperprocalcitonemia is related to noninfectious postoperative severe systemic inflammatory response syndrome associated with cardiovascular dysfunction after coronary artery bypass graft surgery

OBJECTIVE

To investigate the role of 3 inflammatory parameters as early markers of severe systemic inflammatory response syndrome (SIRS) induced by coronary artery bypass graft surgery.

DESIGN

Prospective study.

SETTING

University hospital.

PARTICIPANTS

Patients (n = 63) undergoing elective coronary artery bypass graft surgery with cardiopulmonary bypass.

MEASUREMENTS AND MAIN RESULTS

The American College of Chest Physicians/Society of Critical Care Medicine classification was used to diagnose SIRS. Organ system failures were used to define severe SIRS. Serum concentrations of the inflammatory parameters (procalcitonin [PCT], C-reactive protein, leukocyte count) were determined before, during, and after surgery. SIRS occurred in 30 (47%) patients after surgery. Seven patients (11%) showed SIRS with greater-than-or-equal1 organ dysfunction (severe SIRS), whereas patients without SIRS had no organ dysfunction. Significantly higher serum levels of PCT were found in patients with severe SIRS from the 6th postoperative hour until the 3rd postoperative day with a peak level of 10.7 plus minus 13.2 ng/mL. No significant difference was detected between serum PCT of patients with SIRS but without any organ dysfunction and patients without SIRS. PCT levels of these patients remained lower than 1.7 ng/mL. Compared with PCT, plasma concentrations of C-reactive protein peaked later on the 2nd postoperative day and were not able to confirm the severity of SIRS. Leukocyte counts were not significantly modified.

CONCLUSIONS

PCT seems to be an appropriate marker to identify the early development of noninfectious postoperative severe SIRS after coronary artery bypass graft surgery with cardiopulmonary bypass.

Systematic elucidation of effects of tranexamic acid on fibrinolysis and bleeding during and after cardiopulmonary bypass surgery

The aim of this study was to systematically elucidate the effects of tranexamic acid on fibrinolysis and bleeding during and after cardiopulmonary bypass (CPB) surgery. Twenty-two patients undergoing CPB surgery were randomized to receive 100 mg/kg tranexamic acid or an equal volume of saline after anesthesia induction and prior to skin incision. Plasma levels of tissue plasminogen activator (t-PA) antigen and activity, crosslinked fibrin degradation products (D-dimer), alpha2-antiplasmin-plasmin complex, and plasminogen activator inhibitor-1 (PAI-1) antigen were measured. Blood samples were obtained after induction of anesthesia, before, during, and after CPB, at the end of surgery, and the next morning after surgery. Intraoperative and postoperative blood loss during 24 h after surgery was recorded. Patients' demographics were similar between the two groups. No patients suffered from thrombotic complications after surgery. In the tranexamic acid group, fibrinolytic activity and secondary fibrinolysis as measured by t-PA activity and D-dimer were markedly suppressed during CPB surgery (P=.042 and P=.015, respectively). Decreased fibrinolytic activity and fibrinolysis were accompanied by reduction of perioperative bleeding in the tranexamic acid group. We could also find a good positive correlation between the peak levels of t-PA activity and D-dimer (r(2)=.4203, P=.0011). No differences in the t-PA antigen, PAI-1 antigen release, and plasmin inhibition by alpha2-antiplasmin were apparent between the two groups. In a randomized, prospective trial of patients undergoing CPB surgery, we demonstrated that the synthetic antifibrinolytic drug tranexamic acid effectively suppresses fibrinolysis by inhibiting t-PA and plasmin activity with clear reduction of perioperative blood loss. While tranexamic acid had no effects on the other important fibrinolytic inhibitors like PAI-1 and alpha2-antiplasmin.

Pharmacologic preservation of the hemostatic system during cardiac surgery

Bleeding after cardiac surgery remains a major potential problem. Numerous pharmacologic approaches to attenuating hemostatic system activation in cardiac surgery patients have been studied to further improve patient management. Therapeutic approaches studied include inhibiting thrombin generation or activation, preserving platelet function, and decreasing the need for transfusion of allogeneic blood products. Pharmacologic approaches to reduce bleeding and transfusion requirements in cardiac surgery patients are based on either preventing or reversing the defects associated with the CPB-induced coagulopathy. The increasing use of platelet inhibitors (clopidogrel and IIb/IIIa receptor antagonists) and new anticoagulants (low-molecular weight heparins, pentasaccharide, recombinant hirudin, bivalirudin, and argatroban) also pose interesting problems in managing cardiac surgery patients. Aprotinin and lysine analogues (epsilon-aminocaproic acid and tranexamic acid) have become mainstay therapeutic agents to prevent bleeding and the potential need for allogeneic transfusion. Newer therapies that are important to consider include the potential of recombinant activated factor VIIa as a therapy for refractory bleeding after cardiac surgery.

Aprotinin in orthotopic liver transplantation: evidence for a prohemostatic, but not a prothrombotic, effect

Aprotinin reduces blood transfusion requirements in orthotopic liver transplantation (OLT). Concern has been voiced about the potential risk for thrombotic complications when aprotinin is used. The aim of this study is to evaluate the effects of aprotinin on the two components of the hemostatic system (coagulation and fibrinolysis) in patients undergoing OLT. As part of a larger, randomized, double-blind, placebo-controlled study, we compared coagulation (fibrinogen level, activated partial thromboplastin time [aPTT], prothrombin time, and platelet count) and fibrinolytic variables (tissue-type plasminogen activator [tPA] antigen and activity, plasminogen activator inhibitor activity, and D-dimer), as well as thromboelastography (reaction time [r], clot formation time, and maximum amplitude) in 27 patients administered either high-dose aprotinin (2 x 10(6) kallikrein inhibitor units [KIU] at induction, continuous infusion of 1 x 10(6) KIU/h, and 1 x 10(6) KIU before reperfusion; n = 10), regular-dose aprotinin (2 x 10(6) KIU at induction and continuous infusion of 0.5 x 10(6) KIU/h; n = 8), or placebo (n = 9) during OLT. Blood samples were drawn at seven standardized intraoperative times. Baseline characteristics were similar for the three groups. During the anhepatic and postreperfusion periods, fibrinolytic activity (plasma D-dimer and tPA antigen levels) was significantly lower in aprotinin-treated patients compared with the placebo group. Interestingly, coagulation times (aPTT and r) were significantly more prolonged in aprotinin-treated patients than the placebo group. No difference was seen in the incidence of perioperative thrombotic complications in the entire study population (n = 137). Aprotinin has an anticoagulant rather than a procoagulant effect. Its blood-sparing (prohemostatic) effect appears to be the overall result of a strong antifibrinolytic and a weaker anticoagulant effect. These findings argue against a prothrombotic effect of aprotinin in patients undergoing OLT.

A standardized multidisciplinary approach reduces the use of allogeneic blood products in patients undergoing cardiac surgery

PURPOSE

Individual and institutional practices remain an independent predictor factor for allogeneic blood transfusion. Application of a standardized multidisciplinary transfusion strategy should reduce the use of allogeneic blood transfusion in major surgical patients.

METHODS

This prospective non randomized observational study evaluated the effects of a standardized multidisciplinary transfusion strategy on allogeneic blood products exposure in patients undergoing non-emergent cardiac surgery. The developed strategy involved a standardized blood conservation program and a multidisciplinary allogeneic blood transfusion policy based mainly on clinical judgement, not only on a specific hemoglobin concentration. Data obtained in a first group including patients operated from September 1997 to August 1998 (Group pre: n=321), when the transfusion strategy was progressively developed, were compared to those obtained in a second group, including patients operated from September 1998 to August 1999 (Group post: n=315) when the transfusion strategy was applied uniformly.

RESULTS

Patient populations and surgical procedures were similar. Patients in Group post underwent acute normovolemic hemodilution more frequently, had a higher core temperature at arrival in the intensive care unit and presented lower postoperative blood losses at day one. Three hundred forty units of packed red blood cells were transfused in 33% of the patients in Group pre whereas 161 units were transfused in 18% of the patients in Group post (P <0.001). Pre- and postoperative hemoglobin concentrations, mortality and morbidity were not different among groups.

CONCLUSION

Development of a standardized multidisciplinary transfusion strategy markedly reduced the exposure of cardiac surgery patients to allogeneic blood.

Antifibrinolytic agents and desmopressin as hemostatic agents in cardiac surgery

OBJECTIVE

To review the use of systemic hemostatic medications for reducing bleeding and transfusion requirements with cardiac surgery.

DATA SOURCES

Articles were obtained through computerized searches involving MEDLINE (from 1966 to September 2000). Additionally, several textbooks containing information on the diagnosis and management of bleeding associated with cardiac surgery were reviewed. The bibliographies of retrieved publications and textbooks were reviewed for additional references.

STUDY SELECTION

Due to the large number of randomized investigations involving systemic hemostatic medications for reducing bleeding associated with cardiac surgery, the article selection process focused on recent randomized controlled trials, metaanalyses and pharmacoeconomic evaluations.

DATA EXTRACTION

The primary outcomes extracted from the literature were blood loss and associated transfusion requirements, although other outcome measures such as mortality were extracted when available.

DATA SYNTHESIS

Although the majority of investigations for reducing cardiac bleeding and transfusion requirements have involved aprotinin, evidence from recent meta-analyses and randomized trials indicates that the synthetic antifibrinolytic agents, aminocaproic acid and tranexamic acid, have similar clinical efficacy. Additionally, aminocaproic acid (and to a lesser extent tranexamic acid) is much less costly. More comparative information of hemostatic agents is needed retative to other outcomes (eg., reoperation rates, myocardial infarction, stroke). There is insufficient evidence to recommend the use of desmopressin for reducing bleeding and transfusion requirements in cardiac surgery, although certain subsets of patients may benefit from its use.

CONCLUSIONS

Of the medications that have been used to reduce bleeding and transfusion requirements with cardiac surgery, the antifibrinolytic agents have the best evidence supporting their use. Aminocaproic acid is the least costly therapy based on medication costs and transfusion requirements.

Tranexamic acid in off-pump coronary surgery: a preliminary, randomized, double-blind, placebo-controlled study

BACKGROUND

We evaluated the hemostatic effects of tranexamic acid, a synthetic antifibrinolytic drug, in patients undergoing beating-heart coronary surgery.

METHODS

Forty consecutive patients were in a double-blind manner, prospectively randomized into two groups: 20 patients received tranexamic acid (bolus of 1 g before skin incision, followed by continuous infusion of 400 mg/hr during surgery), and 20 patients received saline. As primary outcomes, bleeding and allogeneic transfusions were considered. D-dimer and fibrinogen plasma levels were also evaluated to monitor the activation of fibrinolysis. Major postoperative thrombotic events, as a potential consequence of antifibrinolytic treatment, were recorded.

RESULTS

The treatment group had significantly lower postoperative bleeding (median [25th to 75th percentiles]: 400 mL [337 to 490 mL] vs 650 ml [550 to 862 mL], p < 0.0001), lower need for allogeneic blood products (1,200 vs 5,300 mL, p < 0.001), and lower postoperative D-dimer plasma levels. No postoperative thrombotic complications were observed in either group.

CONCLUSIONS

In this initial series of patients undergoing off-pump coronary surgery, tranexamic acid appears to be effective in reducing postoperative bleeding and the need for allogeneic blood products.

Comparison of the effects of a cell saver and low-dose aprotinin on blood loss and homologous blood usage in patients undergoing valve surgery

OBJECTIVE

To compare 2 important techniques of blood conservation, use of a cell saver and low-dose aprotinin, in terms of blood loss and homologous blood usage in patients undergoing cardiac valve surgery.

DESIGN

Prospective, randomized.

SETTING

Tertiary care hospital.

PARTICIPANTS

Sixty adult patients undergoing elective valve surgery.

INTERVENTIONS

The patients were divided into 3 groups of 20 each. In group 1, aprotinin in the dose of 30,000 KIU/kg was added to the pump prime, with a further dose of 15,000 KIU/kg added at the end of each hour of cardiopulmonary bypass. In group 2, a cell-saver system was used to collect all blood at the operation site for processing in preparation for subsequent reinfusion. Group 3 patients acted as a control group and underwent routine management, which included collection of autologous blood during the pre-cardiopulmonary bypass period. A hemoglobin of <8 g/dL was considered as an indication for bank blood transfusion in the postoperative period.

MEASUREMENTS AND MAIN RESULTS

The chest tube drainage was significantly less in group 1 compared with groups 2 and 3, with total drainage (median [interquartile range]) amounting to 250 mL [105 to 325 mL] vs. 700 mL [525 to 910 mL] in group 2 and 800 mL [650 to 880 mL] in group 3 (p < 0.001). The patients in groups 1 and 2 required significantly less bank blood (median [interquartile range]) as compared with group 3 (350 mL [0 to 525 mL], 350 mL [0 to 350 mL], and 1050 mL [875 to 1050 mL]; p < 0.001), respectively. Cell saver provided 410 +/- 130 mL of hemoconcentrated blood in group 2. The average preoperative hemoglobin concentration was 11.3 g/dL, and it was around 9 g/dL on the 7th postoperative day. The hemoglobin concentration at various stages during hospitalization in all 3 groups was similar.

CONCLUSIONS

Low-dose aprotinin and a cell saver are effective and comparable methods of blood conservation. Aprotinin helps by decreasing the postoperative drainage, and a cell saver helps by making the patient's own blood available for transfusion.

Update on cardiopulmonary bypass

Investigations into cardiopulmonary bypass continue to refine knowledge and clinical practice. Recent investigations have emphasized neurological complications, introducing the possibility of genetic predisposition as a risk factor. Appropriate flows, pressures, and hematocrit levels during cardiopulmonary bypass continue to create controversy. Whereas previous debate has centered around appropriate temperature management, recent discussions consider the possibility that mild hypothermia after cardiopulmonary bypass might be neuroprotective. Meta-analyses and prospective investigations continue to suggest the virtual equivalence of aprotinin and lysine analogues in reducing bleeding and transfusion after cardiopulmonary bypass. Several recent studies identified the mechanisms and severity of the inflammatory response to cardiopulmonary bypass, as well as possible techniques for attenuating inflammation.

On-site coagulation monitoring does not affect hemostatic outcome after cardiac surgery

BACKGROUND

Rapid coagulation tests are now available for monitoring of bleeding patients after cardiac surgery. As inappropriate blood use in these patients may be due to lack of timely coagulation data, we studied the effect of an algorithm with on-line coagulation monitoring on transfusions in these patients.

METHODS

Prospectively, patients bleeding (>1.5 ml kg(-1) 15 min(-1)) after cardiac surgery were randomly assigned to two groups: in group A (n=28), hemostatic treatment during the immediate recovery period (1 h after surgery) was based on an algorithm with on-site hemostasis monitoring, whereas during the same period group B patients (n=30) were managed solely according to the clinician's judgement; laboratory tests other than activated clotting time after heparin neutralization were prohibited.

RESULTS

Cumulative chest tube drainage up to 16 h and total transfusion requirements did not differ between the groups. Using a platelet transfusion trigger of 100x10(9)/l, significantly more patients received platelets during the immediate recovery period in the algorithm group than in the control group (14 vs. 3 patients, P=0.001). Desmopressin acetate was administered more often in group A than in group B (8 vs. 2 patients, P=0.04).

CONCLUSIONS

Algorithm-based therapy increased utilization of hemostatic interventions during the immediate recovery period without any obvious benefit to the hemostatic outcome. Re-evaluation of the platelet transfusion trigger seems warranted.

Anti-fibrinolytic use for minimising perioperative allogeneic blood transfusion

BACKGROUND

Concerns regarding the safety of transfused blood have prompted re-consideration of the use of allogeneic (blood from an unrelated donor) blood transfusion.

OBJECTIVES

To assess the effects of the anti-fibrinolytic drugs aprotinin, tranexamic acid, and epsilon aminocaproic acid, on peri-operative red blood cell (RBC) transfusion.

SEARCH STRATEGY

We searched MEDLINE (to May 1998), EMBASE (to December 1997), web sites of international health technology assessment agencies (to May 1998). References in identified trials and review articles were checked and authors contacted to identify any additional studies.

SELECTION CRITERIA

Randomised controlled trials of anti-fibrinolytic drugs in adults scheduled for non-urgent surgery.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed trial quality and extracted data.

MAIN RESULTS

We found 61 trials of aprotinin (7027 participants). Aprotinin reduced the rate of RBC transfusion by a relative 30% (RR=0.70: 95%CI: 0.64 to 0.76). The average absolute risk reduction (ARR) was 20.4% (95%CI: 15.6% to 25.3%). On average, aprotinin use saved 1.1 units of RBC (95%CI: 0.69 to 1.47) in those requiring transfusion. Aprotinin also significantly reduced the need for re-operation due to bleeding (RR=0.40: 95%CI: 0.25 to 0.66). We found 18 trials of tranexamic acid (TXA) (1,342 participants). TXA reduced the rate of RBC transfusion by a relative 34% (RR=0.66: 95%CI: 0.54 to 0.81). This represented an ARR of 17.2% (95%CI: 8.7% to 25.7%). TXA use resulted in a saving of 1.03 units of RBC (95%CI: 0.67 to 1.39) in those requiring transfusion. We found four trials of epsilon aminocaproic acid (EACA) (208 participants). EACA use resulted in a statistically non-significant reduction in RBC transfusion (RR=0.48: 95%CI: 0.19 to 1.19). Comparisons between agents Eight trials made 'head-to-head' comparisons between TXA and aprotinin. There was no significant difference between the two drugs in the rate of RBC transfusion: RR=1.21 (95%CI: 0.83 to 1.76) for TXA compared to aprotinin. Adverse Effects Aprotinin did not seem to be associated with an excess risk of adverse effects, including thrombo-embolic events (thrombosis RR=0.64: 95%CI: 0.31 to 1.31) and renal failure (RR=1.19: 95%CI: 0.79 to 1.79). Fewer data were available for TXA and EACA.

REVIEWER'S CONCLUSIONS

From this review it appears that aprotinin reduces the need for red cell transfusion, and the need for re-operation due to bleeding, without serious adverse effects. However, there was significant heterogeneity in trial outcomes, and some evidence of publication bias. Similar trends were seen with TXA and EACA, although the data were rather sparse. The poor evaluation of these latter drugs is unfortunate as results suggest they may be equally as effective as aprotinin, but are significantly cheaper. The evidence reviewed here supports the use of aprotinin in cardiac surgery. Further small trials of this drug are not warranted. Future trials should be large enough to compare the efficacy and cost-effectiveness of aprotinin with that of TXA and EACA.

Desmopressin for minimising perioperative allogeneic blood transfusion

BACKGROUND

Public concerns regarding the safety of transfused blood have prompted re-consideration of the use of allogeneic (from an unrelated donor) red blood cell (RBC) transfusion, and a range of techniques designed to minimise transfusion requirements.

OBJECTIVES

To examine the evidence for the efficacy of desmopressin (1-deamino-8-D-arginine-vasopressin), in reducing perioperative blood loss and the need for red cell transfusion in patients who do not have congenital bleeding disorders.

SEARCH STRATEGY

Articles were identified by: computer searches of OVID MEDLINE, EMBASE, and Current Contents (to August 2000) and web sites of international health technology assessment agencies (to May 1998). References in the identified trials and review articles were checked and authors contacted to identify additional studies.

SELECTION CRITERIA

Randomised controlled parallel group trials in which adult patients, scheduled for non-urgent surgery, were randomised to DDAVP, or to a control group, who did not receive the intervention.

DATA COLLECTION AND ANALYSIS

Trial quality was assessed using criteria proposed by Schulz et al. (1995) and Jadad et al. (1996). The principal outcomes were: the number of patients exposed to red cells, and the amount of blood transfused. Other clinical outcomes are detailed in the review.

MAIN RESULTS

Fourteen trials of DDAVP (N=1034) reported data on the proportion of patients exposed to allogeneic RBC transfusion. In subjects treated with DDAVP the relative risk of exposure to peri-operative allogeneic blood transfusion was 0.98 (95%CI: 0.88 to 1.10) compared with control. In DDAVP-treated patients the relative risk of requiring re-operation due to bleeding was 0.56 (95%CI: 0.18 to 1.73). There was no statistically significant effect overall for mortality and non-fatal myocardial infarction in DDAVP-treated patients compared with control (RR=1.53: 95%CI: 0.58 to 4.05) and (RR=1.52: 95%CI: 0.67 to 3.49) respectively.

REVIEWER'S CONCLUSIONS

There is no convincing evidence that desmopressin minimises perioperative allogeneic RBC transfusion in patients who do not have congenital bleeding disorders. These data suggest that there is no benefit of using DDAVP as a means of minimising perioperative allogeneic RBC transfusion. This meta-analysis had 90% power to detect a relative risk reduction of at least 17% for receiving a red cell transfusion at alpha = 0.05 (two-sided).

Aprotinin administration in the pericardial cavity does not prevent platelet activation

OBJECTIVES

Aprotinin is frequently administered systemically to patients undergoing cardiopulmonary bypass to inhibit activation of platelets and plasma protein systems and thus reduce postoperative blood loss. Two reports on local aprotinin administration, that is, into the pericardial cavity, also indicated improvement in postoperative blood loss, but the underlying mechanism was not investigated. We previously reported the disappearance of glycoprotein Ib from the platelet surface and the appearance of platelet-derived microparticles in the pericardial cavity of patients undergoing cardiopulmonary bypass as signs of platelet activation. Here, we investigated whether such local aprotinin administration reduced platelet activation.

METHODS

In a double-blind study, 6 patients received aprotinin (500,000 KIU) into the pericardial cavity during the operation and 7 patients received a placebo. Platelet surface glycoprotein Ib expression, concentration of microparticles, and concentration of complexes of platelets with leukocytes, erythrocytes, or each other, were measured by flow cytometry.

RESULTS

We confirmed the reduced glycoprotein Ib expression and the increased concentration of microparticles in the pericardial cavity, as previously reported, and found no increased concentration of platelet complexes. However, no differences between aprotinin and placebo treatments were observed in these platelet activation parameters in the pericardial cavity or the systemic circulation.

CONCLUSION

We conclude that administration of aprotinin into the pericardial cavity during cardiopulmonary bypass and at concentrations similar to the systemic application does not reduce platelet activation in that compartment or the systemic circulation.

Cost effectiveness of epoetin-alpha to augment preoperative autologous blood donation in elective cardiac surgery

OBJECTIVE

The objective of this study was to assess the cost effectiveness of using epoetin-alpha (erythropoietin) to augment preoperative autologous donation (PAD) of blood prior to elective cardiac surgery.

DESIGN AND SETTING

We designed a decision-analytic model incorporating the risk of receiving allogeneic blood, the costs of blood products, the likelihood of developing transfusion-related diseases, the costs of transfusion-related diseases and their impact on life expectancy, and the effect of epoetin-alpha on the probability of transfusion.

INTERVENTIONS

The efficacy of epoetin-alpha was derived from data from a meta-analysis of published randomised trials comparing the use of epoetin-alpha to augment PAD with the use of PAD alone. Estimates for the other parameters were obtained by a systematic review of the literature.

MAIN OUTCOME MEASURES AND RESULTS

The use of epoetin-alpha reduced the proportion of patients receiving allogeneic transfusions by 60% (from 31.6 to 12.7%). However, this led to only a modest benefit of 0.000035 life years gained per patient and an incremental cost per life year gained of $Can44.6 million (1998 Canadian dollars). A detailed sensitivity analysis confirmed that the cost-effectiveness ratio was larger than that which is generally considered acceptable.

CONCLUSIONS

Our study indicates that the use of epoetin-alpha to reduce perioperative allogeneic transfusions in cardiac surgery is not cost effective.

Liver transplantation in a Jehovah's Witness with ankylosing spondylitis

PURPOSE

Orthotopic liver transplantation is typically associated with large volume blood loss. Technological and pharmacological advances permit liver transplantation in patients who formerly were not candidates for this surgery because of strict limitations on blood product administration. We describe a liver transplant in a Jehovah's Witness with ankylosing spondylitis.

CLINICAL FEATURE

A 49-yr-old Jehovah's Witness with ankylosing spondylitis and end stage liver disease secondary to sclerosing cholangitis underwent orthotopic liver transplantation. Recombinant human erythropoietin (4,000 IU sc every two days for four weeks, then 4,000 IU sc every week) established a normal hemoglobin concentration preoperatively (> 140 g x L(-1) compared with 120 g x L(-1) baseline). Intraoperatively, strategies for reducing risk of blood product transfusion included avoidance of hypothermia (T>35 degrees C), minimal blood sampling (four 1 ml samples), normovolemic hemodilution (two units), administration of Aprotinin (2 million units bolus dose followed by infusion of 500,000 u x hr(-1)), and return of blood (1,500 ml) scavenged from the operative field. Estimated blood loss was 2,200 mi. The preoperative and postoperative hemoglobin concentration was 147 g x L(-1) (hematocrit 0.45) and 123 g x L(-1) (hematocrit 0.37), respectively. No blood products were required and he was discharged three weeks postoperatively without complication.

CONCLUSION

Technological and pharmacological advances allow patients to undergo surgery traditionally associated with large volume blood loss with reduced risk of blood product administration.

Use of interventions to minimise perioperative allogeneic blood transfusion in Australia. A survey by the International Study of Perioperative Transfusion (ISPOT) Study Group

OBJECTIVE

To investigate use of interventions to minimise need for perioperative transfusion of allogeneic blood in surgical units in Australia.

DESIGN

Two questionnaire-based surveys of practice.

SETTING

All hospitals in Australia, 1996-1997.

PARTICIPANTS

Survey 1: all Australian hospitals that have at least 50 beds and undertake surgery; Survey 2: surgical units identified as using the interventions.

MAIN OUTCOME MEASURES

Reported rates of use of the various interventions (preoperative autologous donation, acute normovolaemic haemodilution [ANH], cell salvage, and drugs); use of guidelines; and perceptions about the appropriateness of current levels of use.

RESULTS

Survey 1 was returned by 349 of 400 hospitals (87%) and Survey 2 by 324 of 578 surgical units (56%). Preoperative autologous donation was most widely used (70% of hospitals), most commonly in units performing orthopaedic or vascular surgery (65% and 37%, respectively). Cell salvage and ANH were used by 27% and 24% of hospitals, respectively, most often in units performing cardiothoracic (40% and 44%, respectively) and vascular surgery (29% and 15%, respectively). These three interventions were used significantly more in private than in public hospitals (P < 0.05). Use of printed guidelines was uncommon. Respondents considered that autologous transfusion techniques should be used more widely because of their perceived efficacy and concerns about safety of allogeneic blood. Perceived barriers to greater use included lack of surgeon or physician interest, uncertain scheduling of surgery in public hospitals and cost (cell salvage). Drugs to minimise blood loss were used by fewer than 10% of hospitals.

CONCLUSIONS

Interventions to minimise the need for perioperative allogeneic blood transfusion (apart from drugs) are widely used in Australia. However, enthusiasm for intraoperative techniques of re-infusing autologous blood needs to be assessed against the evidence of their efficacy and cost-effectiveness.