A comparison of bleeding and transfusion in patients who undergo coronary artery bypass grafting via sternotomy with and without cardiopulmonary bypass

The pressure field as a methodology for fluid management and red cell preservation during cardiac surgery

PURPOSE

Anemia and red cell transfusion contribute to morbidity and mortality of surgery. The concept of patient blood management to mitigate preoperative anemia, optimize coagulation, conserve red cells intraoperatively and accept lower post-operative transfusion thresholds has recently gained widespread acceptance across a range of surgical disciplines. Fluid administration is likely to contribute significantly to perioperative anemia and red-cell transfusion requirements, yet a robust basis for managing fluid administration in this context has not been articulated. There is an urgent need for this.

METHODS

We developed 'the pressure field method' as a novel approach to guiding the administration of fluid and drugs to optimize tissue perfusion. The pressure field method was used for the intraoperative management of 67 patients undergoing semi-elective cardiac surgery. We compared intraoperative anemia and transfusion requirements in this cohort with a conventional group of 413 patients undergoing cardiac surgery.

RESULTS

In the pressure field group, no patients required transfusion whereas in the conventional group, 16% required transfusion during bypass and these patients received an average of 2.4 units of packed red cells (P < 0.0001). The average decrease in hemoglobin in the pressure field group was only 13 g/L, whereas in the conventional group it was 52 g/L (P < 0.0001). 80% of the pressure field group received no intravenous fluid during cardiac surgery, and the average intraoperative fluid load was 115 mL.

CONCLUSION

The pressure field method appears to reduce transfusion requirements due to decreased intraoperative fluid loading.

Off-Pump Coronary Artery Bypass Grafting; is it Still Relevant?

Off-pump Coronary Artery Bypass Grafting (OPCAB) experienced a resurgence in the 1980s -2000s and developed steadily with improvement of the instrumentation and techniques. However questions about graft patency and long-term survival of OPCAB patients still exist. This review attempts to explore the current relevance of OPCAB.

Do women benefit more than men from off-pump coronary artery bypass grafting?

Objectives

Outcomes after coronary artery bypass grafting (CABG) are worse in women than in men. This study aims to investigate whether off-pump coronary artery bypass (OPCAB) surgery improves the outcomes in women by comparing different outcome measures in both genders.

Methods

Patients who underwent isolated CABG, either on-pump (ONCAB) or OPCAB, between January 1998 and June 2017 were included. Primary endpoints were 30-day and 120-day mortality. Logistic regression models were constructed to evaluate the effect of the CABG technique on important outcomes such as mortality and the need for blood transfusion.

Results

The data of 17,052 patients were analysed, 3,684 of whom were women (414 OPCAB) and 13,368 men (1,483 OPCAB). The mean number of grafts was lower in the OPCAB group of both genders (p < 0.001). Postoperatively, both men and women undergoing OPCAB surgery received fewer red blood cell transfusions (p < 0.001) and had higher postoperative haemoglobin levels (p < 0.001) than those undergoing ONCAB. Early mortality occurred less frequently after OPCAB surgery in both genders, although the difference was not significant. However, 120-day mortality was significantly lower after OPCAB surgery in women, even after correction for preoperative risk factors [odds ratio (OR) = 0.356, 95% confidence interval (CI) 0.144–0.882, p = 0.026]. The difference in 120-day mortality was not significant in men (OR = 0.787, 95% CI 0.498–1.246, p = 0.307).

Conclusions

Women undergoing CABG benefit more from OPCAB surgery than from ONCAB surgery in terms of 120-day mortality. This difference was not found in men in our patient population.

Fish Oil and Perioperative Bleeding

Background Fish oil is among the most common natural supplements for treatment of hypertriglyceridemia or prevention of cardiovascular disease. However, concerns about theoretical bleeding risk have led to recommendations that patients should stop taking fish oil before surgery or delay in elective procedures for patients taking fish oil by some health care professionals. Methods and Results We tested the effect of fish oil supplementation on perioperative bleeding in a multinational, placebo-controlled trial involving 1516 patients who were randomized to perioperative fish oil (eicosapentaenoic acid+docosahexaenoic acid; 8-10 g for 2-5 days preoperatively, and then 2 g/d postoperatively) or placebo. Primary outcome was major perioperative bleeding as defined by the Bleeding Academic Research Consortium. Secondary outcomes include perioperative bleeding per thrombolysis in myocardial infarction and International Society on Thrombosis and Hemostasis definitions, chest tube output, and total units of blood transfused. Participants' mean (SD) age was 63 (13) years, and planned surgery included coronary artery bypass graft (52%) and valve surgery (50%). The primary outcome occurred in 92 patients (6.1%). Compared with placebo, risk of Bleeding Academic Research Consortium bleeding was not higher in the fish oil group: odds ratio, 0.81; 95% CI, 0.53-1.24; absolute risk difference, 1.1% lower (95% CI, -3.0% to 1.8%). Similar findings were seen for secondary bleeding definitions. The total units of blood transfused were significantly lower in the fish oil group compared with placebo (mean, 1.61 versus 1.92; P<0.001). Evaluating achieved plasma phospholipid omega-3 polyunsaturated fatty acids levels with supplementation (on the morning of surgery), higher levels were associated with lower risk of Bleeding Academic Research Consortium bleeding, with substantially lower risk in the third (odds ratio, 0.30 [95% CI, 0.11-0.78]) and fourth (0.36 [95% CI, 0.15-0.87]) quartiles, compared with the lowest quartile. Conclusions Fish oil supplementation did not increase perioperative bleeding and reduced the number of blood transfusions. Higher achieved n-3-PUFA levels were associated with lower risk of bleeding. These novel findings support the need for reconsideration of current recommendations to stop fish oil or delay procedures before cardiac surgery. Clinical Trial Registration URL: https://www.clinicaltrials.gov . Unique identifier: NCT00970489.

Local use of ankaferd blood clotter in emergent beating heart coronary artery bypass grafting

Background:

Severe beeding which requiring massive blood transfusion after emergent beating heart surgery is shown to be 1–3%. Therefore, complications and side effects of transfusion can be seen. The aim of this study was to investigate the effectiveness of Ankaferd blood clotter (ABC) as a new topical herbal blood clotter to decrease mediastinal bleeding in emergent beating heart CABG patients who medicated with clopidogrel and acetyl salisilic acite (ASA) prior to CABG surgery.

Materials and Methods:

25 CABG patients received a high dose clopidogrel (600 mgr) and 300 mgr ASA have been included into the study (ABC group). 25 patients have also been included into the study for comparison (placebo group, PG). After the administration of protamine sulphate, a 10 ml of ABC solution has been sprayed to the surgical area including mediastinum and epicardial sac. We compared mediastinal drenaige, reoperation due to tamponade, and required blood and blood products in both groups.

Results:

The mean amount of bleeding after operation was 230 ml in ABC group, and 490 ml in CG (P=0.001). In ICU, bleeding in ABC group and CG was 410ml and 680ml, respectively (P=0.0022). The mean total bleeding from mediastinum was 530±280 mL and 990±440 mL In ABC and CG group, respectively (P=0.001). The amount of autotransfusion was as follows: 175 mL in ABC group, and 290 mL in CG (P=0.002). No patient needed the surgical revision in ABC group, but four patients (16%) from CG group because of cardiac tamponade. Seventeen patients from CG required blood transfusion due to low hematocrite level postoperatively. In CG, the mean hematocrite level was 17±2,3. Transfusion of fresh frozen plasma and platelets in ABC group and CG were as follows: 0.2 and 0 in ABC group, and 0.3and 0.4 in CG.

Conclusion:

Our study showed that the local use of 10 mL ABC reduces bleeding significantly. Therefore, transfusion requirements of PRBC, platelets, and total blood units in patients on clopidogrel and ASA undergoing emergent beating heart CABG. To provide cardiac tamponade because of excessive mediastinal bleeding and requirement of blood transfusion after emergent CABG patients who previously administered clopidogrel and ASA, we propose local use of ABC solution as a potent coagulant agent.

Off-pump surgery: is it beneficial in patients with left ventricular dysfunction?

On-pump coronary artery bypass surgery remains the gold standard for complex multivessel disease. Off-pump revascularization has matured as a technique over the last twenty years, but is used in less than 20% of cases worldwide. The poor uptake has been attributed to the significant learning curve in learning the procedure and conflicting evidence reports, together with concerns over mortality related conversion, graft patency and completeness of revascularization. Given these concerns, patient selection continues to be paramount and the subgroups that benefit most are hotly debated. Patients with left ventricular dysfunction constitute a high-risk subgroup which is enlarging in size. There is some evidence to suggest that avoidance of cardiopulmonary bypass in this group may lead to superior results in terms of early mortality, non-cardiac complications and organ dysfunction. Even with the theoretical risk of incomplete revascularization, the technique may be an attractive option in managing high-risk patients.

Predictors of transfusion of packed red blood cells in coronary artery bypass grafting surgery

OBJECTIVES

Finding predictors of blood transfusion may facilitate the most efficient approach for the use of blood bank services in coronary artery bypass grafting procedures. The aim of this retrospective study is to identify preoperative and intraoperative patient characteristics predicting the need for blood transfusion during or after CABG in our local cardiac surgical service.

METHODS

435 patients undergoing isolated first-time CABG were reviewed for their preoperative and intraoperative variables and analyzed postoperative data. Patients were 255 males and 180 females, with mean age 62.01 ± 10.13 years. Regression logistic analysis was used for identifying the strongest perioperative predictors of blood transfusion.

RESULTS

Blood transfusion was used in 263 patients (60.5%). The mean number of transfused blood products units per patient was 2.27 ± 3.07 (0-23) units. The total number of transfused units of blood products was 983. Univariate analysis identified age >65 years, weight <70 Kg, body mass index <25 Kg/m2, hemoglobin <13mg/dL, hematocrit < 40% and ejection fraction <50%, use of cardiopulmonary bypass (CPB), not using an internal thoracic artery as a bypass, and multiple bypasses as significant predictors. The strongest predictors using multivariate analysis were hematocrit < 40% (OR 2.58; CI 1.62-4.15; P<0.001), CPB use (OR 2.00; CI 1.27-3.17; P=0.003) and multiple bypasses (OR 2.31; CI 1.31-4.08; P=0.036).

CONCLUSIONS

The identification of these risk factors leads to better identification of patients with a greater probability of using blood, allocation blood bank resources and cost-effectiveness use of blood products.

Beating Heart versus Conventional Coronary Bypass Surgery: Our Experience

BACKGROUND

Off-pump Coronary Artery Bypass (OPCAB) has become the standard surgical treatment of Coronary Artery Disease in most centres in India. It is clear from the current evidence that, in certain patients, OPCAB offers advantages over conventional Coronary Artery Bypass Grafting (CABG). Experience of this procedure in the Armed Forces is highlighted.

METHODS

Retrospective analysis of 200 nonrandomized consecutive patients taken up for OPCAB and 200 conventional CABG between Jan 2005 and Dec 2007 was done. The European system for cardiac operative risk evaluation (euroSCORE) was used in all patients. Perioperative morbidity and mortality was compared in the two groups.

RESULT

OPCAB was possible in 192 (96 %) out of 200 patients taken up for this procedure. Eight patients required cardiopulmonary bypass (CPB) to complete the revascularization. Incidence of reoperation for bleeding was 2.5% in OPCAB and 6% in CABG In the CABG group 2% patients developed severe bleeding complications, 3% required ventilation for more than 24 hour, 1% required renal replacement therapy, 1% had acute respiratory distress syndrome and 3.5% had neuro-psychiatric manifestations. Incidence of these complications in OPCAB patients was lower or NIL. Overall mortality in the OPCAB group was 1.5% and 2% in the CABG group. However only one patient out of 192 (0.5%) who underwent successful OPCAB died, while two patients out of eight who required conversion to CPB in this group died. Incidence of stroke, deep sternal infection and mortality was similar in both groups.

CONCLUSION

OPCAB is safe, effective and can be offered to more than 90% patients as the primary strategy for surgical myocardial revascularization. It has lower overall morbidity than conventional CABG Its main limitations are hemodynamic instability and inability to find a deeply embedded target vessel. Both these factors affect the outcome adversely making conventional CABG a better option in these situations.

Off-pump surgery does not eliminate microalbuminuria or other markers of systemic inflammatory response to coronary artery bypass surgery

OBJECTIVE

To evaluate whether off-pump surgery attenuates microalbuminuria and other markers of systemic inflammatory response to coronary artery bypass surgery as compared to surgery performed using cardiopulmonary bypass.

DESIGN

Forty-three adult patients undergoing elective coronary artery bypass grafting surgery were operated on with or without cardiopulmonary bypass (CPB). Microalbuminuria, serum C-reactive protein, and oxygenation and lung function parameters were measured at several time points until the first postoperative morning.

RESULTS

The urinary albumin/creatinine ratio was low in both groups before surgery, but reached a maximum level at the end of CPB or just after opening the last coronary artery clamp in the off-pump group (p<0.05). The urinary albumin/creatinine ratio remained slightly elevated in both groups until the morning after the operation (p<0.05). There were no statistical differences between groups. Serum C-reactive protein remained at the initial level the evening after the operation, but increased by the first postoperative morning in both groups (p<0.001). The alveolar-arterial gradient for oxygen partial pressure rose significantly after the operation in the intensive care unit in both groups (p<0.0001). The shunt fraction of the pulmonary circulation did not change in either group.

CONCLUSIONS

Off-pump coronary artery surgery did not prevent the acute phase inflammatory response measured in the present study. The acute phase inflammatory response after coronary artery bypass surgery is more likely a response to the surgical trauma itself rather than to CPB.

Predictors of packed red cell transfusion after isolated primary coronary artery bypass grafting--the experience of a single cardiac center: a prospective observational study

Background

Preoperative patients' characteristics can predict the need for perioperative blood component transfusion in cardiac surgical operations. The aim of this prospective observational study is to identify perioperative patient characteristics predicting the need for allogeneic packed red blood cell (PRBC) transfusion in isolated primary coronary artery bypass grafting (CABG) operations.

Patients and Methods

105 patients undergoing isolated, first-time CABG were reviewed for their preoperative variables and followed for intraoperative and postoperative data. Patients were 97 males and 8 females, with mean age 58.28 ± 10.97 years. Regression logistic analysis was used for identifying the strongest perioperative predictors of PRBC transfusion.

Results

PRBC transfusion was used in 71 patients (67.6%); 35 patients (33.3%) needed > 2 units and 14 (13.3%) of these needed > 4 units. Univariate analysis identified female gender, age > 65 years, body weight ≤ 70 Kg, BSA ≤ 1.75 m², BMI ≤ 25, preoperative hemoglobin ≤ 13 gm/dL, preoperative hematocrit ≤ 40%, serum creatinine > 100 μmol/L, Euro SCORE (standard/logistic) > 2, use of CPB, radial artery use, higher number of distal anastomoses, and postoperative chest tube drainage > 1000 mL as significant predictors. The strongest predictors using multivariate analysis were CPB use, hematocrit, body weight, and serum creatinine.

Conclusion

The predictors of PRBC transfusion after primary isolated CABG are use of CPB, hematocrit ≤ 40%, weight ≤ 70 Kg, and serum creatinine > 100 μmol/L. This leads to better utilization of blood bank resources and cost-efficient targeted use of expensive blood conservation modalities.

Postoperative complications of coronary artery bypass grafting surgery

Coronary artery bypass grafting (CABG) surgery continues to be an effective and well-used intervention for coronary artery disease. Older patients and those with sicker hearts will become the norm. In spite of increased risk for patients undergoing CABG, overall mortality rates have decreased. Nursing contributions to these improved outcomes cannot be overestimated. Continued understanding and appreciation of these complications will be necessary to effectively care for patients and create optimal outcomes.

Warm ischemia provokes inflammation and regional hypercoagulability within the heart during off-pump coronary artery bypass: a possible target for serine protease inhibition

OBJECTIVE

Accumulating evidence suggests that a hypercoagulable state influences early graft failure after off-pump coronary artery bypass (OPCAB). We hypothesized that regional myocardial ischemia caused by obligatory periods of coronary occlusion during OPCAB is an important trigger for this prothrombotic state.

METHODS

Using a series of biomarkers, 60 consecutive patients undergoing OPCAB were monitored for myocardial injury (myoglobin), inflammation (TNF-alpha, IL-8) and thrombosis (thrombin generation-F1.2, contact activation pathway-FXII-a, platelet derived microparticles-via flow cytometry). The transcardiac gradients of these markers were determined by assaying both arterial and coronary sinus blood just after protamine administration. Intramyocardial pH was monitored continuously during coronary occlusion in a subset (N=30 grafts, 11 patients). The influence of management strategies affecting hemostasis (e.g. antiplatelet therapy, anti-fibrinolytics, peak activated clotting time (ACT) during heparinization) was analyzed.

RESULTS

Ischemic injury, depicted by the transcardiac myoglobin gradient, significantly correlated with intramyocardial acidosis during coronary occlusion (R=0.96, p<0.0001) and predicted the transcardiac gradients of TNF-alpha (R=0.83, p<0.001) and F1.2 (R=0.72, p<0.0001). Transcardiac F1.2 strongly correlated with TNF-alpha (R=0.73, p=0.01) and IL-8 (R=0.51, p=0.02). Patients receiving aprotinin (N=20) showed significantly lower transcardiac gradients for myoglobin (4.1+/-7.5% vs 72.9+/-108.8% change, p=0.002), F1.2 (31+/-37% vs 89+/-149%, p=0.03), FXII-a (2.6+/-4.1% vs 19.2+/-34%, p=0.04) and microparticles (7+/-3.9% vs 12.9+/-8%, p=0.01).

CONCLUSIONS

Strong correlations between myocardial ischemia and the transcardiac gradients of markers for inflammation and thrombosis suggest that even brief episodes of coronary occlusion in the beating heart may have pathophysiologic consequences. Aprotinin, but not other factors that influence the coagulation system, appears to mitigate this process during OPCAB.

Coagulation and fibrinolytic protein kinetics in cardiopulmonary bypass

The development of Cardiopulmonary Bypass (CPB) catopulted the field of cardiothoracic surgery into a new dimension--one that changed the lives of individuals with congenital and acquired heart disease worldwide. Despite its contributions, CPB has clear limitations and creates unique challenges for clinicians and patients alike, stemming from profound hemostatic pertubations and accompanying risk for bleeding and possibly thrombotic complications.

Pituitary Apoplexy and CABG: Should We Change Our Strategy?

Patients with pituitary adenoma that had coronary artery bypass grafting with cardiopulmonary bypass had pituitary apoplexy develop with neurologic deficits and even death. Four patients with pituitary adenoma underwent coronary artery bypass grafting operations (3 patients had coronary artery bypass grafting on bypass, 1 of them with known pituitary adenoma. All of them had pituitary apoplexy develop with neurologic deficits). One patient with known pituitary adenoma who had a coronary artery bypass grafting operation off pump was neurologically intact. Our recommendation is to consider operating on patients with pituitary adenoma who need coronary artery bypass grafting operation off pump, and to prevent pituitary apoplexy that cardiopulmonary bypass may cause.

Does Systemic Leukocyte Filtration Affect Perioperative Hemorrhage in Cardiac Surgery? A Systematic Review and Meta-Analysis

Cardiopulmonary bypass causes a systemic inflammatory reaction. Activation of leukocytes is an important part of this process, and is known to directly contribute to the development of postoperative coagulopathy, and thus hemorrhage. The removal of leukocytes from the cardiopulmonary bypass circulation, using specialized filters, has been proposed as one method for attenuating this inflammatory response. However, there is no consensus on its effectiveness. We used meta-analytical techniques to systematically assess the literature reporting on the potential effect of systemic leukofiltration on perioperative hemorrhage. Random effects modeling was used to calculate overall estimate, and heterogeneity was assessed. Systemic leukofiltration made no significant impact on chest tube drainage in the first 24 hours (weighted mean difference [WMD], x23.9 ml; 95% confidence interval [CI], x95.48-47.61; p = 0.51) or on the total packed red cell transfusion requirements of each patient (WMD, 7.84 ml; 95% CI, x80.13-95.81; p = 0.86). The studies performed in this area thus far are highly heterogeneous, due in part to relatively poor-quality design and inadequate matching of their study groups. Although further high-quality trials on systemic leukofiltration may be appropriate, other strategies to reduce the coagulopathy associated with cardiopulmonary bypass should be sought and evaluated.

Perioperative blood transfusion and blood conservation in cardiac surgery: the Society of Thoracic Surgeons and The Society of Cardiovascular Anesthesiologists clinical practice guideline

BACKGROUND

A minority of patients having cardiac procedures (15% to 20%) consume more than 80% of the blood products transfused at operation. Blood must be viewed as a scarce resource that carries risks and benefits. A careful review of available evidence can provide guidelines to allocate this valuable resource and improve patient outcomes.

METHODS

We reviewed all available published evidence related to blood conservation during cardiac operations, including randomized controlled trials, published observational information, and case reports. Conventional methods identified the level of evidence available for each of the blood conservation interventions. After considering the level of evidence, recommendations were made regarding each intervention using the American Heart Association/American College of Cardiology classification scheme.

RESULTS

Review of published reports identified a high-risk profile associated with increased postoperative blood transfusion. Six variables stand out as important indicators of risk: (1) advanced age, (2) low preoperative red blood cell volume (preoperative anemia or small body size), (3) preoperative antiplatelet or antithrombotic drugs, (4) reoperative or complex procedures, (5) emergency operations, and (6) noncardiac patient comorbidities. Careful review revealed preoperative and perioperative interventions that are likely to reduce bleeding and postoperative blood transfusion. Preoperative interventions that are likely to reduce blood transfusion include identification of high-risk patients who should receive all available preoperative and perioperative blood conservation interventions and limitation of antithrombotic drugs. Perioperative blood conservation interventions include use of antifibrinolytic drugs, selective use of off-pump coronary artery bypass graft surgery, routine use of a cell-saving device, and implementation of appropriate transfusion indications. An important intervention is application of a multimodality blood conservation program that is institution based, accepted by all health care providers, and that involves well thought out transfusion algorithms to guide transfusion decisions.

CONCLUSIONS

Based on available evidence, institution-specific protocols should screen for high-risk patients, as blood conservation interventions are likely to be most productive for this high-risk subset. Available evidence-based blood conservation techniques include (1) drugs that increase preoperative blood volume (eg, erythropoietin) or decrease postoperative bleeding (eg, antifibrinolytics), (2) devices that conserve blood (eg, intraoperative blood salvage and blood sparing interventions), (3) interventions that protect the patient's own blood from the stress of operation (eg, autologous predonation and normovolemic hemodilution), (4) consensus, institution-specific blood transfusion algorithms supplemented with point-of-care testing, and most importantly, (5) a multimodality approach to blood conservation combining all of the above.

Does off-pump coronary artery bypass surgery reduce secretion of plasminogen activator inhibitor-1?

Prior studies showed that postoperative increase in plasminogen activator inhibitor-1 (PAI-1) levels is associated with an increased risk of graft occlusion after coronary artery bypass surgery (CABG). This prospective study aimed to compare the changes of PAI-1 antigen levels after off-pump and on-pump CABG. Forty-four patients admitted for elective CABG were randomised to on-pump (n=22) or off-pump (n=22) surgery. Serum samples were collected for estimation of PAI-1 and tissue plasminogen activator (t-PA) antigen levels preoperatively and 2 h after the operation. The groups were similar in terms of age, weight, gender ratio and extent of coronary disease, left ventricular function and number of grafts per patient. Fibrinogen and t-PA levels increased postoperatively in both the groups when compared with baseline values. After operation, statistical analysis revealed that increase of PAI-1 values was higher in off-pump group (44.1+/-9.1 vs. 25.3+/-6.9) than on-pump group (37.2+/-5.5 vs. 27.3+/-7.8, p=0.002). This study shows that increase in PAI-1 antigen values in patients who undergo off-pump (beating heart) CABG is significantly higher than in those who undergo conventional CABG with cardiopulmonary bypass.

Blood conservation strategies in cardiac surgery

Despite the continuous efforts to increase the safety of blood components, red blood cell transfusions remain associated with some risks and side effects. Therefore, numerous techniques have been developed to decrease blood use, but they also carry risks and bear costs. Most of them are frequently used in cardiac surgery, which still consumes a large part of the available blood supply. Among western countries the use of alternative techniques, but also transfusion practice, has been shown to vary markedly. 'Blood conservation' is a global concept engulfing all possible strategies aimed at reducing patients' exposure to allogeneic blood components. The development of the 'best strategy' consists of the selection of those techniques that are most appropriate to the local specific situation. It implies the establishment of a reliable system, collecting data both at the surgical team and at the medical level.

Early administration of clopidogrel is safe after off-pump coronary artery bypass surgery

BACKGROUND

Patients who undergo off-pump coronary artery bypass graft surgery (OPCAB) may be hypercoagulable with an increased risk of graft thrombosis due to the lack of platelet dysfunction that accompanies "on-pump" surgery. Clopidogrel may be indicated in these patients to prevent recurrent ischemic events. The purpose of this observational study was to determine the safety of early clopidogrel administration after OPCAB.

METHODS

Thirty-day follow-up of 364 consecutive OPCAB patients (January to June, 2002) was determined from a computerized database. One hundred ninety-three patients received clopidogrel 4 hours postoperatively if chest tube output was less than 100 cc/h for 4 hours, then daily for 4 weeks. Aspirin was administered preoperatively and postoperatively to all patients. Telephone follow-up was made 6 to 12 months after OPCAB.

RESULTS

None of the patients who received clopidogrel in the early postoperative period required reoperation for mediastinal hemorrhage. Mean chest tube drainage at 24 hours was 1,024 +/- 563 mL in patients who received clopidogrel and 942 +/- 501 mL in patients who did not receive clopidogrel. The total number of blood units transfused and the number of patients receiving blood transfusions were similar between groups. In-hospital mortality was 1.6% in patients who received clopidogrel and 3.5% in patients who did not receive clopidogrel. No group differences in mortality or adverse cardiac events were observed at 6 months. Gastrointestinal bleeding occurred in 2.2% clopidogrel patients versus 0.7% of patients who did not receive clopidogrel.

CONCLUSIONS

When administered according to our postoperative protocol, OPCAB patients can safely receive clopidogrel in the early postoperative period without increased risk for mediastinal hemorrhage.

Effect of aprotinin on postoperative blood loss in off-pump coronary artery bypass surgery

BACKGROUND AND AIM OF THE STUDY

Off-pump coronary artery bypass (OPCAB) enables a reduction in postoperative complications, particularly bleeding and transfusion. Nevertheless, a significant percentage of patients still needs transfusion. The effect of antifibrinolytic therapy on postoperative bleeding as part of OPCAB is still not widely described. The purpose of this study was to investigate the potential benefit of aprotinin in OPCAB.

METHODS

We conducted a retrospective comparative study with a historical control group. Consecutive patients undergoing off-pump coronary bypass were divided in two groups: 40 patients were operated without any antifibinolytic drug (group C); 40 patients received aprotinin (group A) during surgery. Patients in group A received a bolus of 2 x 10(6) KIU during 30 minutes, followed by a continuous infusion of 0.5 x 10(6) KIU per hour until the end of surgery. The same protocol was used during the whole study period.

RESULTS

Preoperative data of the two groups did not differ except for the number of grafts performed, which was higher in group A. Prothrombin time and activated clotting time increased in both groups after surgery. The use of packed red blood cells or fresh frozen plasma was not significantly different between both groups. Postoperative blood loss was significantly reduced in the aprotinin group (540 mL +/- 320 vs. 770 mL +/- 390, p = 0.006). No increase in postoperative troponin values was found in group A.

CONCLUSIONS

Aprotinin significantly reduced postoperative blood loss without reducing the transfusion rate. Aprotinin was not associated with any increase in postoperative complications.

Effect of Clopidogrel Premedication in Off-Pump Cardiac Surgery

Background— Premedication with clopidogrel has reduced thrombotic complications after percutaneous coronary revascularization procedures. However, because of the enhanced and irreversible platelet inhibition by clopidogrel, patients requiring surgical revascularization have a higher risk of bleeding complications and transfusion requirements. A principal benefit of surgical coronary revascularization without cardiopulmonary bypass is its lower hemorrhagic sequelae. The purpose of this study was to evaluate the effect of preoperative clopidogrel administration in the incidence of hemostatic reexploration, blood product transfusion rates, morbidity, and mortality in patients undergoing off-pump coronary artery bypass graft surgery using a large patient sample and a risk-adjusted approach.

Methods and Results— Two hundred eighty-one patients (17.9%) did and 1291 (82.1%) did not receive clopidogrel before their surgery, for a total of 1572 patients undergoing isolated off-pump coronary artery bypass graft surgery between January 2000 and June 2002. Risk-adjusted logistic regression analyses and a matched pair analyses by propensity scores were used to assess the association between clopidogrel administration and reoperation as a result of bleeding, intraoperative and postoperative blood transfusions received, and the need for multiple transfusions. Hemorrhage-related preoperative risk factors identified in the literature and those found significant in a univariate model were used. The clopidogrel group had a higher likelihood of hemostatic reoperations (odds ratio [OR], 5.1; 95% confidence interval [CI], 2.47 to 10.47; P <0.01) and an increased need in overall packed red blood cell (OR, 2.6; 95% CI, 1.94 to 3.60; P <0.01), multiple unit (OR, 1.6; 95% CI, 1.07 to 2.48; P =0.02), and platelet (OR, 2.5; 95% CI, 1.77 to 3.66; P <0.01) transfusions. Surgical outcomes and operative mortality (1.4% versus 1.4%; P =1.00) were not statistically different.

Conclusions— Clopidogrel administration in the cardiology suite increases the risk for hemostatic reoperation and the requirements for blood product transfusions during and after off-pump coronary artery bypass graft surgery.

Impact of Off-Pump Coronary Artery Bypass Surgery on Postoperative Bleeding: Current Best Available Evidence

Cardiopulmonary bypass (CPB) is a prerequisite for open-heart surgery, and is a procedure routinely used. CPB exposes blood to artificial surfaces, to mechanical trauma from the pump, to alterations in temperature, and to dilution with fluids, whole blood, plasma products, and drugs, and leads to the activation of platelets, coagulation, and fibrinolysis. Coagulopathy during cardiac surgery with CPB results in impairment in hemostasis and subsequently higher morbidity and mortality. Recent advances in surgical techniques and postoperative management have aimed at reducing postoperative morbidity and mortality. Off-pump coronary artery bypass (OPCAB) surgery is one such advance that attempts to avoid the deleterious effects of extracorporeal circulation by performing myocardial revascularization without CPB. Emerging evidence from several randomized controlled trials (RCTs) as well as large registries such as the Society of Thoracic Surgeons (STS) database suggests that OPCAB reduces the postoperative morbidity and mortality. This review article attempts to evaluate the current best available evidence from RCTs on the impact of OPCAB on postoperative bleeding and transfusion requirements.

Evaluation of intraoperative autotransfusion filtration for hepatectomy and pancreatectomy

BACKGROUND

Hepatectomy and pancreatectomy are often associated with significant intraoperative blood loss leading to postoperative anemia, which has been demonstrated to lead to increased perioperative morbidity, a prolonged hospital stay, and decreased overall survival. Cancer has remained an absolute contraindication to autotransfusion because of the unproven concern about reinfusion of malignant cells. Thus, the aim of this study was to test for the presence of malignant cells in autotransfused filtered blood in patients undergoing major pancreatic and liver resection.

METHODS

A prospective study of 20 consecutive patients evaluated the presence of malignant cells from autotransfusion filtered blood after resection by flow cytometric and immunohistochemical methods.

RESULTS

Ten patients underwent major hepatectomy for metastatic colorectal cancer, with a median blood loss of 500 mL (range, 200-700 mL). Three patients received a total of six units of packed red blood cells. Ten patients underwent pancreaticoduodenectomy for adenocarcinoma with a median blood loss of 400 mL (range, 200-1300 mL). Five patients received a total of nine units of packed red blood cells. Flow cytometry did not demonstrate the presence of any cytokeratin-positive carcinoma cells in filtered blood.

CONCLUSIONS

Intraoperative autotransfusion for major hepatectomy in metastatic colorectal cancer and pancreatectomy for adenocarcinoma is safe and should begin to be evaluated in a phase II study for efficacy.

Postoperative Hyperthermia Following Off-Pump Versus On-Pump Coronary Artery Bypass Surgery

OBJECTIVE

Hyperthermia is common in the first 24 hours following coronary artery bypass graft surgery (CABG) with cardiopulmonary bypass (CPB). An inflammatory response to CPB is often implicated in the pathophysiology of this fever. Unlike CABG with CPB, the temperature pattern after off-pump CABG (OPCAB), where CPB is avoided, has not yet been described. The purpose of this study was to describe the postoperative temperature pattern following OPCAB and to compare it with that following on-pump cardiac surgery.

DESIGN

Retrospective, observational study.

SETTING

Tertiary care university hospital.

PARTICIPANTS

Consenting patients undergoing CABG or OPCAB procedures.

INTERVENTIONS

Observational.

MEASUREMENTS AND MAIN RESULTS

Of the CABG patients, 89% had temperature elevations above 38 degrees C, versus 44% of the OPCAB patients (P = 0.04). Peak body temperature was higher in the on-pump patients (CABG 38.5 degrees C +/- 0.4 degrees C versus OPCAB 37.9 degrees C +/- 0.5 degrees C; P = 0.002), as was the area under the curve for temperatures greater than 38 degrees C (CABG 1.6 +/- 1.7 degrees C/hr versus OPCAB 0.4 +/- 1.2 degrees C/hr; P = 0.02).

CONCLUSIONS

Off-pump CABG surgery patients experience less hyperthermia compared with on-pump CABG patients. The reasons for a lower incidence and severity of hyperthermia after OPCAB surgery are not known, but may be related to a reduced inflammatory response.

Outcome of elderly patients undergoing open-heart surgery in a developing country

To evaluate and compare the outcome of open-heart surgery in elderly patients with a concurrent group of younger patients in a developing country, data of all adult patients who underwent open-heart surgery during the period of 3 years from January 1999 to December 2001 were collected prospectively. Demographic data such as age and gender, other data such as preoperative diagnoses, comorbid illnesses, type of surgery, time of cardio-pulmonary bypass, length of stay and hospital outcome were recorded. The characteristics of patients above the age of 65 years were compared with a concurrent cohort of patients aged less than 65 years. One hundred and forty-five adult patients underwent open-heart surgeries in 3 years, and the overall mortality rate was 4.8%. The much common surgeries were coronary artery bypass grafting, valve repair/replacement surgery and surgery for adult congenital heart diseases. Forty-five (31%) patients were above the age of 65 years. The mortality rate was 2.2% for patients who were aged 65 years and above, in comparison with that of the concurrent cohort of younger patients (6%). This was probably because of more number of surgeries for congenital heart diseases in the latter group. However, even with other surgeries such as coronary artery bypass grafting, the elderly group of patients did equally well as the younger group. Elderly patients tolerate cardiac surgery well, and age should not be an exclusive criterion to decide against open-heart surgery.

[Off-pump versus on-pump coronary artery bypass surgery. Comparison of 270 case-matched elderly patients]

INTRODUCTION

Off-pump versus on-pump coronary artery bypass surgery: it still remains a matter of debate which method results in a lower incidence of perioperative morbidity and mortality. This case-matched study evaluates the outcome of elderly patients in both groups.

METHODS

All patients aged 75 and older, who underwent CABG from 1998 to 2002, were examined retrospectively. They were matched according to Euroscore and the number of diseased vessels. The Student's t-test and chi-square test were used where appropriate.

RESULTS

270 CABG patients were considered: 135 off-pump and 135 on-pump patients. Mean age was 78.4 +/- 3.1 versus 77.5 +/- 2.9 years, respectively. EuroSCORE was 7.11 +/- 2.3 in both groups; number of distal anastomoses per patient 1.7 +/- 0.74 versus 2.6 +/- 0.63 (p < 0.001), operation time 138 versus 177 minutes (p < 0.001). There were no significant differences in postoperative complications including hospital mortality 3.0 versus 3.7%, renal failure 8.9 versus 12.1% (new onset), acute myocardial infarction 1.5 versus 4.4% and cerebral events 0 versus 1.5%, respectively. The number of transfused packed cells was 2.6 +/- 2.8 versus 4.6 +/- 5.3 (p < 0.001). Intubation time and ICU stay were similar in both groups.

CONCLUSION

OPCAB is not associated with a reduction of perioperative mortality and morbidity in patients aged 75 and older.