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Background: Introduction of completely heparin-coated cardiopulmonary bypass (CPB) circuits combined with reduced systemic anticoagulation has been shown to reduce postoperative bleeding and requirements for allogeneic transfusions after cardiac surgery. However, some uncertainty exists whether this effect is due to the reduced amount of heparin or to the heparinized surface itself. Therefore, a retrospective study was undertaken, comparing two different anticoagulation protocols applied to coronary artery bypass patients treated with identical heparin-coated CPB equipment., Method: Over a 12 month period all coronary artery bypass patients operated with extracorporeal circulation were subjected to a Duraflo II heparin-coated circuit (Baxter Healthcare Corp, Bentley Laboratories Division, Irvine, Calif) and full heparin dose (activated clotting time [ACT] > 480 seconds; Group F, n = 651). Over the next 24 months, all coronary patients who were treated with an identical circuit combined with reduced systemic heparinization (ACT > 250 seconds) were included in Group R (n = 675). Except for the different anticoagulation protocols, all treatment regimens before, during, and after the operation remained unchanged throughout the study period., Results: There were no statistically significant differences in any major demographic or operative parameters. In Group R, the postoperative bleeding was mean 665 +/- 257 ml versus 757 +/- 367 ml in Group F (p < 0.0001), and the perioperative decrease in hemoglobin concentration was significantly lower in Group R (22 +/- 1.2 gm/L versus 25 +/- 1.3 gm/L, p < 0.0001). The time for postoperative ventilatory support was shorter in Group R (1.7 +/- 1.3 hours versus 1.9 +/- 1.1 hours in Group F, p = 0.0006), and the incidence of new episodes of atrial fibrillation after the operation was lower (26.4% in Group R versus 32.8% in Group F, p = 0.01). There were no significant differences in the incidences of perioperative myocardial infarction, stroke, transient neurological disturbances, physical rehabilitation, or mortality. No technical or coagulation problems were recorded in either group., Conclusion: The use of Duraflo II coated circuits for CPB combined with reduced anticoagulation decrease postoperative bleeding and hemoglobin loss compared with full heparin dose treatment. In addition, the intubation time was shorter and the incidence of postoperative atrial fibrillation was lower in the patients treated with low heparin doses.

Objective: The two most commonly used heparin-coated systems for cardiopulmonary bypass (CPB) are the Carmeda Bio-Active Surface (CBAS) (Medtronic, Minneapolis, MN, USA) and the Duraflo II coating (Baxter Healthcare, Irvine, CA, USA). The two surfaces are technically unequal and previous experimental studies have demonstrated disparities in effects on the immune system and blood cells. However, little is known concerning the influence of the two surfaces on markers for brain and myocardial dysfunction., Methods: Forty patients undergoing elective, primary coronary bypass grafting with CPB were prospectively randomized to either the CBAS system or the Duraflo II circuit. During and after CPB, biological markers for brain dysfunction and myocardial injury were analysed., Results: Both markers for brain dysfunction S-100B and neuron-specific enolase (NSE) increased significantly during CPB (p = 0.01). The elevation during bypass correlated significantly with the duration of CPB (r = 0.39 and r = 0.38, respectively, both p < 0.02). NSE was somewhat more elevated in the Duraflo II group at the end of CPB (p = 0.01) and 5 h after CPB (p = 0.02); for S-100B, there were no intergroup differences. Also, the markers related to myocardial injury, myoglobin and creatine kinase (CK-MB) mass increased during CPB (p = 0.01), while elevation of troponin-I occurred 5 h after CPB (p = 0.01). There were no statistically significant intergroup differences. No significant correlation was seen between the release of cardiac markers and the duration of CPB. The clinical course was similar in both groups., Conclusions: Except for a slightly higher elevation of NSE at the end of CPB and 5 h after CPB in the Duraflo II group, there were no significant differences between the CBAS group and the Duraflo II group concerning markers for brain and myocardial dysfunction.

Objectives: The use of heparin-coated circuits for cardiopulmonary bypass attenuates the postperfusion inflammatory response. Postoperative bleeding and the need for allogeneic blood transfusions are reduced, particularly in combination with lowered systemic anticoagulation. The two most commonly used heparin-coated systems are the Carmeda BioActive Surface (Medtronic Inc, Minneapolis, Minn) and the Duraflo II coating (Baxter Healthcare Corp, Bentley Laboratories Division, Irvine, Calif). The 2 surfaces are technically unequal, and previous experimental studies have demonstrated disparities in effects on the immune system and the blood cells. However, no larger comparative studies of relevant clinical end points have thus far been reported., Methods: Over a 24-month period, all patients undergoing coronary artery bypass were prospectively randomized to one of the two heparin-coated circuits. Altogether, 1336 consecutive patients were included. The heparin dose was reduced in all cases, with an activated coagulation time of more than 250 seconds. Clinical data were consecutively collected and stored on a computer for comparative analyses., Results: There were no statistically significant differences in any demographic or operative parameters. The Duraflo II patients required less heparin to keep the target-activated clotting time, confirming the previous finding of some leakage of heparin from the surface to the circulation. Otherwise, there were no significant differences in time for ventilatory support (Duraflo II, 1.7 +/- 1.3 hours; Carmeda BioActive Surface, 1.6 +/- 1.0 hours; P =.37), amount of postoperative mediastinal drainage (Duraflo II, 665 +/- 257 mL; Carmeda BioActive Surface, 688 +/- 243 mL; P =.07), need for allogeneic blood-plasma transfusions (Duraflo II, 4.2% of the patients; Carmeda BioActive Surface, 4.4% of the patients; P =.93), or hemoglobin concentration at hospital discharge (Duraflo II, 120 +/- 13 g/L; Carmeda BioActive Surface, 119 +/- 13 g/L; P =.08). The effects on renal function and platelets were similar, as were the incidences of perioperative myocardial infarction (Duraflo II, 1.5%; Carmeda BioActive Surface, 1.5%; P =.96), stroke (Duraflo II, 1.3%; Carmeda BioActive Surface, 1.2%; P =.47), and hospital mortality (Duraflo II, 1 [0.14%] patient; Carmeda BioActive Surface, 3 [0.45%] patients; P =.31)., Conclusions: Despite differences in technology, complexity, and effects on biologic markers, no clinical differences were observed between the Carmeda BioActive Surface system and the Duraflo II coating after coronary artery bypass operations. The overall clinical results were favorable in both groups, confirming the safety and feasibility of routine use of heparin-coated circuits in combination with reduced systemic anticoagulation.

Background: Coronary artery bypass grafting was performed in 5,658 consecutive patients during the period 1989-1998. Due to changes over time, both in patients' risk profile and surgical strategies, a review was undertaken to study trends and results after coronary artery bypass surgery., Material and Methods: Our database includes more than 160 variables per patient, covering preoperative risk factors, catheterization data, operative and postoperative results. These data form the basis for analysis over time., Results: Median age increased for both genders, from 58 years to 64 years for males and 62.5 years to 69 years for females. The female proportion increased from 12.8% to 19.8%. A high operative risk profile was registered in 23.7% in 1989 compared to 61.8% in 1998. Heparin-coated extracorporeal equipment and blood cardioplegia were gradually introduced in routine practice. Despite higher age and operative risk profile the morbidity and hospital mortality (0.41% overall) remained nearly unchanged., Interpretation: Due to continuous improvement of technical equipment and treatment strategies, coronary artery bypass surgery represents a safe option for both high and low risk patients.

Postoperative organ dysfunction after cardiac operations has been related to the damaging effects of cardiopulmonary bypass (CPB). These complications are considered to be mediated partly by complement activation and subsequent activation of leucocytes due to the contact between blood and the large nonendothelial surfaces in the bypass circuit. Removal of leucocytes by filtration during the reperfusion period may potentially reduce the postoperative morbidity after CPB. Forty patients undergoing elective, primary coronary artery bypass grafting were randomized to initial identical bypass circuits until the aortic crossclamp was released. Then, the ordinary arterial line filter was closed and either a leucocyte depletion filter (n = 20), or a control filter (n = 20) was incorporated in the circuits during the reperfusion period of CPB. Blood samples were drawn at fixed intervals and analysed for white blood cell and platelet counts, plasma concentration of myeloperoxidase, C3-complement activation products, the terminal complement complex, and interleukins (IL)-6 and -8. The numbers of circulating white blood cells in the leucocyte-depleted group decreased during the reperfusion period from 5.5 (4.8-6.8) to 5.3 (4.4-6.2) x 10(9)/l, and increased in the control group from 6.5 (5.1-8.0) to 7.4 (5.7-9.0) x 10(9)/l. Two hours postoperatively the total white blood cell count in the leucocyte-depleted group was 14.7 (12.1-17.2) x 10(9)/l, and in the control group 17.6 (14.5-20.7) x 10(9)/l. The differences between the groups were statistical significant (p = 0.05). There were no statistically significant differences between the groups with regard to other test parameters or clinical data. We conclude that the use of leucocyte filters during the reperfusion period in elective coronary artery bypass surgery significantly reduced the number of circulating leucocytes, whereas no effects were seen for granulocyte activation measured as myeloperoxidase release, platelet counts, complement activation, or IL-6 and -8 release. The clinical benefit of leucocyte filters in routine or high risk patients remains to be demonstrated and is suggested to be dependent on both the efficacy and the biocompatibility of the filters.

The main purpose of this study was to estimate the costs and savings related to a consistent autotransfusion programme. More than 8,000,000 ml of autologous blood or blood-containing fluid were collected from 3,637 consecutive patients undergoing coronary artery bypass and returned to the patients during and after the operation. Economic analyses revealed a price of NOK 13 million (approximately 2 million USD) for this amount of autologous blood, or NOK 3,500 (600 USD) per patient. In the present series the need for bank blood or blood products was modest, since 69 patients (1.9%) received packed red cells, with or without plasma, 76 patients (2.1%) were given plasma transfusions only, and 11 patients (0.3%) received platelets. Thus, 95.7% of the patients were not exposed to any homologous blood products during the stay in hospital. Absence of morbidity related to the low homologous blood transfusion rate was assumed to save costs substantially, although this saving was difficult to calculate in terms of currency. Post-operative complications were few, and the total in-hospital mortality rate was 0.4%.

Background: The concepts of minimally invasive coronary artery bypass grafting have gained increasing attention and interest from cardiac surgeons. Operations through small incisions are mostly applied to patients with less extensive coronary disease, mostly single-vessel disease. The aim of this study was to identify a baseline level of conventional coronary bypass grafting for this group of patients, particularly with regard to surgical complications and immediate results., Methods: Of 3,637 consecutive patients undergoing coronary artery bypass grafting during the period 1989 to 1995, 99 patients (2.7%) were identified to have single-vessel disease. The preoperative and hospital data of this subset of patients were analyzed., Results: The left internal mammary artery was grafted in 96% of the patients, either as single graft to the left anterior descending artery or sequentially to the left anterior descending artery and a diagonal branch. Additional vein grafts were placed in 36 patients, and the mean number of distal anastomoses was 1.6 +/- 0.6. Mean ischemic time and cardiopulmonary bypass time were 15.3 +/- 9.6 minutes and 29.0 +/- 12.5 minutes, respectively. The patients were weaned from the ventilator 1.5 +/- 0.8 hours postoperatively, and all patients were out of bed the morning after the operation. No patients required homologous blood or plasma transfusions. The morbidity rate was low, and all patients survived., Conclusions: For this highly selected group of patients, coronary artery bypass grafting based on median sternotomy, cardiopulmonary bypass, and cardioplegic arrest carries a very high rate of immediate success. Such data may be useful as a baseline when considering the costs and benefits of new surgical procedures.

Background: The use of completely heparin coated cardiopulmonary bypass circuits in combination with a reduced systemic heparin dose has previously been shown to reduce postoperative bleeding after cardiac operations. However, it has remained unknown whether this effect was related to the improved biocompatibility of the heparin-treated surfaces per se or to the reduced exposure to circulating heparin. Therefore we investigated patients undergoing heparin-coated extracorporeal circulation and full systemic heparinization., Methods: Two hundred seventeen patients having first-time myocardial revascularization were prospectively randomized either to a group in which a completely ("tip-to-tip") heparin-coated circuit (Duraflo II) was used for perfusion (n = 107) or to a control group (n = 110) in which an uncoated, but otherwise identical, circuit was used. Full systemic heparinization was induced in both groups (activated clotting time, > 480 seconds). The postoperative blood loss, requirements for homologous blood transfusions, clinical performance, and complications were recorded., Results: The amount of postoperative mediastinal drainage was nearly identical in the two groups. The mean 18-hour drainage was 694 +/- 313 mL in the heparin-coated group and 679 +/- 269 mL in the control group (p = not significant). Three patients in the heparin-coated group and 6 patients in the control group received homologous red blood cell transfusions (p = not significant). The incidence of postoperative atrial fibrillation was significantly lower in the heparin-coated group (21.8%) than in the control group (43.1%) (p = 0.002). Otherwise, there were no significant differences in the extubation times, the incidence of perioperative myocardial infarction, the creatinine concentration, the incidence of neurologic dysfunction, the progress in physical rehabilitation, or the hemoglobin concentration at discharge., Conclusions: The use of completely heparin coated cardiopulmonary bypass circuits and full systemic heparinization in patients undergoing coronary artery bypass procedures did not reduce postoperative bleeding or change clinical performance, except for a significant decrease in the incidence of postoperative atrial fibrillation.

The possible activation of monocytes to express tissue factor procoagulant activity (TF-PCA) during CPB (cardiopulmonary bypass) was investigated. 22 patients undergoing myocardial revascularization were randomly assigned to two groups. In group C, heparin-coated circuits (Duraflo II) and reduced systemic heparinization (ACT > 250s) were used. In group NC, non-coated circuits and standard heparin administration (ACT > 480s) were used. Adherent monocytes retrieved from the oxygenators immediately after bypass arrest showed a 2-3-fold increase in TF-PCA when compared to circulating cells pre-CPB (P < 0.01). When cell PCA was expressed as percent change from pre-CPB (baseline) values, circulating monocytes in group NC at CPB-arrest showed a 2-fold increase in PCA compared to group C (P < 0.05). Moreover, the percent increase in PCA of oxygenator-retrieved monocytes was 7-fold in group NC and 2-fold in group C (P < 0.008 and P < 0.004, respectively). Thus, heparin-coating of the extracorporeal circuit reduced induction of adherent cell TF-PCA by 70% (P < 0.05). Thus, monocyte TF-PCA may cause activation of the extrinsic coagulation pathway during CPB surgery. It is apparent that heparin-coating enhanced biocompatibility of extracorporeal circuits. Reduced systemic heparinization in group C proved to be safe. However, further reduction of heparin administration may not be advisable, since monocytes were still activated in the coated oxygenator.

Background: Cardiopulmonary bypass with heparin-coated circuits allows reduced amounts of systemic heparin. Heparin inhibits activation of the complement cascade experimentally, but the effects of different levels of systemic heparin on activation of complement and granulocytes in patients have remained unknown., Methods: Fifty-two patients undergoing coronary artery bypass procedures were studied. Cardiopulmonary bypass circuits completely coated with surface-bound heparin were used for one group given low-dose heparin (n = 17) (activated clotting time > 250 seconds), and was compared with a second group having normal high-dose heparin (activated clotting time > 480 seconds) (n = 18). A third control group was perfused with ordinary uncoated circuits and a full heparin dose (n = 17)., Results: During cardiopulmonary bypass, the C3 activation products C3b, iC3b, and C3c increased markedly in all three groups compared with baseline, but significantly less in the two heparin-coated groups (high dose, median maximal increase 58 arbitrary units (AU)/mL; low dose, 48 AU/mL) compared with the uncoated control group (74 AU/mL) (p < 0.01). The difference between the two coated groups was not significant. Similarly, the maximal increase in terminal SC5b-9 complement complex was considerably lower in the heparin-coated groups (high dose, 2.5 AU/mL; low dose, 2.6 AU/mL) compared with the level observed in the uncoated control group (5.3 AU/mL) (p < 0.01). The release of the granulocyte activation enzymes myeloperoxidase and lactoferrin increased from the beginning of the operation, with peak levels at the end of cardiopulmonary bypass (p < 0.01). The concentration of lactoferrin was significantly (p < 0.01) reduced in the low heparin dose group compared with the two other groups receiving normal high heparin doses, indicating that circulating heparin is an important granulocyte agonist, acting independently of the presence or absence of heparin-coated surfaces. Also for myeloperoxidase a higher level was observed in the high heparin dose group., Conclusions: Complement activation was significantly reduced in both heparin-coated groups and was independent of the level of systemic heparinization, whereas granulocyte activation was reduced only in patients who received low doses of systemically administered heparin. The results indicate that a moderate reduction of the systemic heparin dose may be an advantage with regard to improved biocompatibility when using heparin-coated cardiopulmonary bypass circuits.

Background: Extracorporeal circulation with circuits coated with surface-bound heparin has allowed reduced levels of systemic heparinization. Clinical benefits have included reduced postoperative bleeding and less homologous blood usage. However, the effects on the hemostatic and fibrinolytic systems have remained in part unknown., Methods and Results: Indications of thrombin generation, platelet activation, and fibrinolytic activity were investigated in patients undergoing coronary artery bypass surgery. Two groups were perfused with cardiopulmonary bypass (CPB) circuits completely coated with surface-bound heparin: one group with low systemic heparin dose (activated clotting time [ACT] > 250 seconds; n = 17) and a second group having a full heparin dose (ACT > 480 seconds; n = 18). A third control group was perfused with ordinary uncoated circuits and full heparin dose (n = 17). The plasma level of thrombin-antithrombin complex and prothrombin fragment 1.2 increased in all groups during bypass, and somewhat more in both the heparin-coated groups toward the end of CPB, compared with the control group (P < .01). However, the increase during CPB was minimal compared with the major elevation observed 2 hours after surgery in all groups. Platelet release of beta-thromboglobulin increased in all groups (P < .01) during CPB and significantly more in the high-dose group compared with the other two groups (P = .03). Fibrinolytic activities were similar in all groups, and there were no indications of major consumption of coagulation factors., Conclusions: Reduced systemic heparinization (ACT > 250 seconds) in patients having extracorporeal circulation with completely heparin-coated circuits did not lead to increased thrombogenicity. Thrombin formation remained within low ranges during CPB compared with patients receiving a full heparin dose and with the major elevations observed after surgery.

Background: When heparinized circuits are used for cardiopulmonary bypass, the amounts of heparin and protamine administered systemically can be reduced. However, it is not entirely known what effects this reduction in systemic anticoagulation has on clinical performance and on the coagulation and fibrinolytic systems., Methods: Two hundred three patients undergoing first-time elective myocardial revascularization were prospectively randomized either to a group in which a completely heparin-coated circuit was used for perfusion (group H; n = 101 patients) and in which a reduced heparin dose was given (activated clotting time, > 250 seconds) or to a control group (group C; n = 102 patients) in which an uncoated, but otherwise identical, circuit was used and in which full systemic heparinization was induced (activated clotting time, > 480 seconds). Indicators of thrombin generation, platelet activation, and fibrinolytic activity were studied in a subset of 34 patients., Results: The total amount of postoperative mediastinal drainage was significantly reduced in group H (median, 575 mL) compared with that in group C (median, 635 mL; p = 0.002). Two patients in group C but none in group H received homologous red blood cell transfusions (p = not significant). The loss of hemoglobin in group H was a median of 21 g/L, and this was significantly lower than the 25 g/L noted in the control group (p = 0.006). During cardiopulmonary bypass, the plasma levels of thrombin-antithrombin complex and prothrombin fragment 1.2 increased in both groups. At the end of cardiopulmonary bypass the plasma levels of these markers of thrombin formation were significantly higher in group H, although the increase was modest compared with the major increase observed 2 hours after operation in both groups. There were no significant intergroup differences in the platelet counts, the concentration of beta-thromboglobulin, or the plasma levels of fibrinogen and D-dimer. No differences in perioperative morbidity, the postoperative kidney function, or the intubation time were observed, and there were no hospital deaths., Conclusions: The combination of complete heparin-coated cardiopulmonary bypass circuits and low systemic heparinization is safe for patients undergoing elective coronary artery bypass procedures and reduces the perioperative blood loss. There was no evidence of increased thrombogenicity, fibrinolytic activity, or consumption of coagulation factors. No clinical or technical side effects were observed.

Background: Ventricular fibrillation after declamping of the aorta after cardioplegic arrest is commonly managed by direct-current countershock. However, in coronary artery bypass grafting, placement of the electrodes can cause mechanical damage to the grafts and anastomoses, and the surgical procedure must be interrupted. As an alternative, intraaortic infusion of potassium chloride through the arterial line from the heart-lung machine was investigated., Methods: In a series of 100 patients with postischemic ventricular fibrillation (group P), 20 mmol of potassium chloride (plus 10 mmol later if necessary) was added to the oxygenator reservoir and perfused through the arterial line into the proximal aorta. The results were compared with those in a matched control group of 100 patients primarily treated with direct-current countershock (group DC)., Results: In group P, the ventricular fibrillation was effectively converted to a supraventricular rhythm in 82% of the patients. The remaining 18 patients required significantly (p < 0.005) fewer electric shocks than the patients in group DC. Serum K+ levels were slightly elevated for a short period after the potassium chloride infusion. Otherwise there were no significant differences in regard to incidence of heart block, temporary epicardial pacing, myocardial infarction, or atrial fibrillation between the two groups., Conclusions: Conversion of postischemic ventricular fibrillation with potassium chloride administered through the arterial line from the heart-lung machine is an effective, gentle, and convenient method. No side effects were noted.

A 60-year-old male patient developed progressive wound ulcerations, simulating wound sepsis after coronary bypass operation. The condition did not respond to intensive antibiotic therapy. Based on clinical signs and biopsy, the diagnosis of pyoderma gangrenosum was made and successfully treated with cyclosporin A. Pyoderma gangrenosum, although extremely rare, must be considered as a possible diagnosis in wound complications unresponsive to traditional therapy.

The contribution of fibrinolysis to postoperative bleeding after cardiopulmonary bypass led to routine use of tranexamic acid, a potent antifibrinolytic drug, for a period of time. Two hundred patients undergoing elective coronary artery bypass operations were studied, one group of 100 patients given tranexamic acid (40 mg/kg) (group I) after bypass and one subsequent group of 100 patients (group II) serving as a control group. All patients were treated by the same team, and the groups were comparable in all major clinical parameters. The mean mediastinal drainage in group I was 565 +/- 239 ml versus 656 +/- 257 ml in group II. Univariate and multivariate analysis revealed statistical significance (p = 0.02) when corrected for body surface area. However, applying a consistent blood conservation protocol, including removal of autologous blood before bypass for retransfusion after bypass, returning of all oxygenator and tubing contents to the patients, and autotransfusion of the mediastinal shed blood up to 18 hours postoperatively, resulted in nearly identical hemoglobin concentration at discharge (119 +/- 14 gm/L in group I and 121 +/- 14 gm/L in group II). The prevalence of postoperative myocardial infarction included five patients in group I compared with one patient in group II. Although not statistically significant (p = 0.2), the difference is of concern. Tranexamic acid has a beneficial effect on reducing postoperative bleeding after coronary artery bypass operations. The routine use of the drug is not recommended, however, because its effect is a weak one, and it may be of potential hazard by precipitating thrombosis and eventual myocardial infarction.

Seventy-three patients with a CarboMedics aortic bileaflet valve prosthesis were examined by Doppler ultrasonography, and 27 of them were also assessed by transseptal catheterization. The ultrasonic mean systolic gradient was 17.1 +/- 5.6 mm Hg for valve size 19 mm, falling gradually with increasing valve size to 6.8 +/- 2.5 mm Hg for size 27 mm. The catheter mean systolic gradient was consistently smaller than the ultrasonic gradient (4.3 +/- 4.8 mm Hg), but Tobit regression analysis showed a significant association between the two methods. In all patients both methods revealed negligible to small amounts of retrograde leakage, which is assumed to be a normal finding for this valve. The effective flow areas of the valves calculated from the ultrasonic data were similar to the in vitro calculated flow areas. The hemodynamic potential of this valve is therefore completely utilized in vivo. The effective orifice area corrected for body surface area increased with increasing valve size, which demonstrates a moderate valve-patient mismatch.

A hemodynamic study of men undergoing elective coronary artery bypass surgery was undertaken to elucidate the side effects of protamine given into the ascending aorta (group A, n = 16) or into the central venous line (group V, n = 16). After termination of extracorporeal circulation, protamine was infused over 120 seconds, and the hemodynamic profile was continuously recorded. During the first minute, the systemic arterial pressure fell to about 60% of the preprotamine level in both groups, but the hemodynamic changes occurred more rapidly (p < 0.05) in group V than in group A, with maximal pressure drop at 61.7 +/- 2.7 vs 74.4 +/- 4.9 seconds. Following spontaneous restoration of the systemic blood pressure, the pulmonary artery pressure rose considerably in both groups, as did the pulmonary capillary wedge and central venous pressures, reaching higher levels in the intravenous group. The cardiovascular responses were again more rapid in group V than in group A (p = 0.004). The degree of systemic hypotension thus did not benefit from use of the intraaortic rather than the intravenous route for administering protamine. The more pronounced and more rapid pulmonary circulatory changes in the intravenous group suggest that the hemodynamic effects of protamine are initiated in the lungs.

During a 30 month period, 1,000 consecutive elective coronary artery bypass operations were performed in 863 men and 137 women. The majority of the patients had no impairment of the left ventricle; more than 66%, however, had one or more operative high risk factors (old age, female sex, low ejection fraction, diabetes, overweight, unstable angina). Perioperative complications, which included prolonged stay in hospital, were noted in 24 patients (2.4%), due to myocardial infarction, wound infection or neurological disorder. Myocardial necrosis, diagnosed by new Q-waves and elevated enzymes, was demonstrated in 31 patients (3.1%), most of whom were asymptomatic. A consistent blood conservation programme resulted in avoidance of any homologous blood products in 96.4% of the patients. The mortality among hospitalized patients was 1/1,000 (0.1%). Elective coronary artery bypass surgery may be performed with a very low rate of mortality and morbidity, which compares very well with the results achieved after alternative revascularization procedures such as percutaneous transluminal coronary angioplasty (PTCA), laser angioplasty and arterectomy.

With use of a nonpharmacological, simple, and inexpensive program for blood conservation, 500 consecutive patients underwent elective coronary artery bypass grafting without need of homologous red cell transfusions in 493 (98.6%). At least one internal mammary artery was grafted in all but 1 patient, with supplemental saphenous vein grafts. Intraoperatively, autologous heparinized blood was removed before bypass and retransfused at the conclusion of extracorporeal circulation. The volume remaining in the oxygenator and tubing set was returned without cell processing or hemofiltration. Using the hard-shell cardiotomy reservoir from the heart-lung machine, autotransfusion of the shed mediastinal blood was continued hourly up to 18 hours after operation. The mean postoperative mediastinal blood loss was 643 +/- 354 mL, whereas 624 +/- 296 mL was autotransfused. Thirteen patients (2.6%) needed reexploration for bleeding, of whom 7 (7/500, 1.4%) received homologous blood. No other patients required red cell transfusions. In addition, 9 patients were given a mean of 2.6 units of fresh frozen plasma because of suspected coagulopathy. No platelets were transfused, and no cryoprecipitate therapy was undertaken. Thus, in total, 484 patients (96.8%) were not exposed to any homologous blood products during the hospital stay. At discharge, the mean hemoglobin concentration was 121 +/- 14 g/L (12.1 +/- 1.4 g/dL) and the hematocrit, 0.36 +/- 0.04. Postoperative complications were few. There was one in-hospital death (0.2%).

Restriction of donor blood transfusions in cardiac surgery should reduce risks of infective contamination and antigenicity. We report a systemic, simple and inexpensive blood conservation program used for 121 consecutive patients who underwent elective coronary artery bypass surgery without need for homologous blood transfusion. The left internal mammary artery was grafted in all cases, in addition to saphenous vein grafts. Autologous, heparinized blood was removed intraoperatively, pre-bypass, and returned to the patient at conclusion of the extracorporeal circulation. The volume remaining in the oxygenator and the tubing set was returned without cell processing or hemofiltration. Using the hard-shell cardiotomy reservoir from the heart-lung machine, autotransfusion of the shed mediastinal blood was continued hourly up to 18 hours after surgery. The mean postoperative mediastinal bleeding was 551 +/- 206 ml, of which 505 +/- 218 ml was autotransfused. No re-exploration for bleeding was required and no homologous red-cell transfusions were given. Five patients each received 1-2 units of fresh frozen plasma because of prolonged bleeding time. Morbidity was low and mortality nil. At discharge the mean hemoglobin was 12.0 +/- 1.4 g/dl and the hematocrit 36.0 +/- 4.2%.

The cardiovascular effects of protamine were studied in 19 men with normal left ventricular function undergoing primary myocardial revascularization. Protamine was given over 120 sec after termination of cardiopulmonary bypass. Arterial and pulmonary pressures, aortic blood flow, central venous pressure, heart rate and electrocardiogram were continuously registered. Pulmonary capillary wedge pressure was recorded at the times of maximal hemodynamic response. The systolic arterial pressure fell from 116 to 66 mmHg about 60 sec after the start of protamine infusion, but spontaneously began to rise after a few seconds, reaching 90% of pre-protamine levels at 126 sec. No inotropic drugs or volume infusion were given. At about 2 min, the mean pulmonary artery pressure rose from 16.3 to 26.2 mmHg and the central venous pressure from 7.0 to 11.4 mmHg. The heart rate and cardiac output were almost unchanged throughout. Systemic hypotension and pulmonary hypertension are suggested to represent true side effects of protamine or protamine/heparin complex. When left ventricular function is good, the hypotension reverses without treatment. Volume infusion may indeed precipitate right heart failure when the pre-load effect is added to the subsequent protamine-induced pulmonary hypertension.

Blood conservation in open heart surgery has become mandatory in order to reduce the risk of viral contamination, and because of limited resources. We have performed 100 consecutive coronary artery bypass operations (13 women/87 men, aged 33-73 years, mean 58 years) without using homologous blood. A strict blood conservation programme was applied, with removal of autologous blood prebypass for retransfusion at the end of surgery, retransfusion of the heart-lung machine content to the patient, and autotransfusion of shed mediastinal blood in the postoperative period. All patients survived the operation and were extubated 1.6 hours (0-6) postoperatively. No patients needed resternotomy for bleeding, and no homologous blood was given. Five patients received 1-2 units of fresh frozen plasma because of coagulopathy. Mean hemoglobin was 12.0 g/100 ml and mean hematocrit was 36% at discharge from hospital. Elective coronary artery bypass surgery can be performed with little or no transfusions of homologous blood.

Arterial and neural damage following total hip replacement is not common. Three cases are reported. The first patient had an isolated femoral nerve damage. The second case developed a false aneurysm arising from the external iliac artery 2 months after hip surgery and the third patient sustained a tear of the external iliac artery during the operation. The nerve and vessel injuries were caused by retractors. In both patients with arterial damages a transitory femoral nerve involvement occurred. The prognosis was good in all patients. Preventive measures are discussed.

Risk factors for operative mortality and long term survival were identified in 144 patients undergoing mitral valve replacement (MVR). The 3-year survival was 77% at a median follow-up time of 3.01 years, including an early mortality of 7.6%. Nineteen preoperative and perioperative variables were analysed by univariate and multivariate methods. The sole risk factor independently predictive of postoperative death was a poor functional class with a relative risk (RR) of 3.17 compared to patients with a better functional class. Independent risk factors of long term survival were; prior heart operation, presence of mitral regurgitation, age at operation and poor functional class. Estimation of the parameters of the Cox's model gave a predicted 3-year survival ranging from 95% to 11% for the most favourable and the less favourable risk factor combinations. Risk factors that affected late death were the presence of ischemic coronary etiology and poor functional class. Two modes of late death were identified each with its prognostic factor. The most common mode was cardiac-related death, its sole risk factor was the presence of ischemic coronary etiology. The RR ratio was 3.2 for patients with ischemic coronary etiology, compared to patients with other etiologies. Sudden cardiac death was the next, its independent risk factor was the age at operation with increasing hazard for younger patients. The RR ratio was 8.55 for a 35-year-old patient compared to a 60-year-old patient.