William DeBois

Comprehensive Multimodality Blood Conservation: 100 Consecutive CABG Operations Without Transfusion

BACKGROUND Despite the recent introduction of a number of technical and pharmacologic blood conservation measures, bleeding and allogeneic transfusion remain persistent problems in open heart surgical procedures. We hypothesized that a comprehensive multimodality blood conservation program applied algorithmically on the basis of bleeding and transfusion risk would provide a maximum, cost-effective, and safe reduction in postoperative bleeding and allogeneic blood transfusion. METHODS One hundred consecutive patients undergoing coronary artery bypass grafting were prospectively enrolled in a risk factor-based multimodality blood conservation program (MMD group). To evaluate the relative efficacy and safety of this comprehensive approach, comparison was made with a similar group of 90 patients undergoing coronary artery bypass grafting to whom the multimodality blood conservation program was not applied but in whom an identical set of transfusion guidelines was enforced (control group). To evaluate the cost effectiveness of the multimodality program, comparison was also made between patients in the MMD group and a consecutive series of contemporaneous, diagnostic-related group-matched patients. RESULTS One hundred consecutive patients in the MMD group underwent coronary artery bypass grafting without allogeneic transfusion. This compared favorably with the control population in whom a mean of 2.2 +/- 6.7 units of allogeneic blood was transfused per patient (34 patients [38%] received transfusion). In addition, the volume of postoperative blood loss at 12 hours in the control group was almost double that of the MMD group (660 +/- 270 mL versus 370 +/- 180 mL [p < 0.001]). Total costs for the MMD group in each of the three major diagnostic-related groups were equivalent to or significantly less than those in the consecutive series of diagnostic-related group-matched patients. CONCLUSIONS Comprehensive risk factor-based application of multiple blood conservation measures in an optimized, integrated, and algorithmic manner can significantly decrease bleeding and need of allogeneic transfusion in coronary artery bypass grafting in a safe and cost-effective manner.

Retrograde Autologous Priming For Cardiopulmonary Bypass: A Safe And Effective Means Of Decreasing Hemodilution And Transfusion Requirements

OBJECTIVES The obligatory hemodilution resulting from crystalloid priming of the cardiopulmonary bypass circuit represents a major risk factor for blood transfusion in cardiac operations. We therefore examined whether retrograde autologous priming of the bypass circuit would result in decreased hemodilution and red cell transfusion. METHODS Sixty patients having first-time coronary bypass were prospectively randomized to cardiopulmonary bypass with or without retrograde autologous priming. Retrograde autologous priming was performed at the start of bypass by draining crystalloid prime from the arterial and venous lines into a recirculation bag (mean volume withdrawal: 880 +/- 150 ml). Perfusion and anesthetic techniques were otherwise identical for the two groups. The hematocrit value was maintained at a minimum of 16% and 23% during and after cardiopulmonary bypass, respectively, in all patients. Patients were well matched for all preoperative variables, including established transfusion risk factors. Subsequent hemodynamic parameters, pressor requirements, and fluid requirements were equivalent in the two groups. RESULTS The lowest hematocrit value during cardiopulmonary bypass was 22% +/- 3% versus 20% +/- 3% in patients subjected to retrograde autologous priming and in control patients, respectively (p = 0.002). One (3%) of 30 patients subjected to retrograde autologous priming had intraoperative transfusion, and seven (23%) of 30 control patients required transfusion during the operation (p = 0.03). The number of patients receiving any homologous red cell transfusions in the two groups during the entire hospitalization was eight of 30 (27%; retrograde autologous priming) versus 16 of 30 (53%; control) (p = 0.03). CONCLUSIONS These data suggest that retrograde autologous priming is a safe and effective means of significantly decreasing hemodilution and the number of patients requiring red cell transfusion during cardiac operations.

Intraoperative autologous blood donation preserves red cell mass but does not decrease postoperative bleeding

BACKGROUND Postoperative bleeding and transfusion remain a source of morbidity and cost after open heart operations. The benefit of the acute removal and reinfusion of fresh autologous blood around the time of cardiopulmonary bypass-a technique known as intraoperative autologous donation (IAD)-has not been universally accepted. We sought to more clearly evaluate the effects of IAD on allogeneic transfusion and postoperative bleeding by removing, preserving, and reinfusing a calculated maximum volume of fresh autologous whole blood. METHODS Ninety patients undergoing coronary artery bypass grafting or valvular operations were prospectively randomized to either have (IAD group) or not have (control group) calculated maximum volume IAD performed. Treatment was otherwise identical. Transfusion guidelines were uniformly applied to all patients. RESULTS An average volume of 1,540 +/- 302 mL of fresh autologous blood was removed and reinfused in the IAD group. Postoperative hematocrits were significantly greater at 12 and 24 hours postoperatively in the IAD group versus the control group despite a significant decrease in both the percentage of patients in whom allogeneic red blood cells were transfused (17% versus 52%; p < 0.01) and the number of red blood cell units transfused per patient per group (0.28 +/- 0.66 and 1.14 +/- 1.19 units; p < 0.01). Conversely, chest tube output, incidence of excessive postoperative bleeding, postoperative prothrombin time, and platelet and coagulation factor transfusion requirement did not differ between groups. CONCLUSIONS These results indicate that intraoperative autologous donation serves to preserve red blood cell mass. Its routine use in eligible patients is therefore justified. However, the removal and reinfusion of an individually calculated maximum volume of fresh autologous blood had no effect on postoperative bleeding or platelet and coagulation factor transfusion requirement. This lack of hemostatic effect belies the beliefs of many about the primary action of IAD, helps to delineate the optimal way in which to perform IAD, and carries implications regarding the use of allogeneic platelet and coagulation factors for the treatment of early postoperative bleeding.

MAST system: a new condensed cardiopulmonary bypass circuit for adult cardiac surgery:

There have been many refinements in cardiopulmonary bypass (CPB) techniques over the past few decades specific to design, materials and function. Despite these improvements, use of the standard length circuit tubing and pump oxygenator alter cellular, biochemical and rheological properties by inducing a systemic inflammatory response, persisting well into the early postoperative phase. We have designed a new condensed CPB circuit, the MAST system, where the oxygenator and the pumps are brought closer to the operating table (within 30 inches) with the help of a series of telescopic swivel steel poles to which they are attached. The control console is retained at the usual remote location of 2 ft behind the MAST system. This configuration accomplishes a decrease in tubing length, priming volume and blood circulatory time within the extracorporeal circuit. Early experience of a hundred consecutive cases utilizing the MAST CPB system is presented along with a comparative analysis of prime volume, hemodilution and transfusion parameters of MAST system vs the low prime system, which is another newly developed CPB circuit utilizing a pediatric oxygenator to reduce prime volume and hemodilution.

The effects of platelet inhibitors on blood use in cardiac surgery.

Platelet inhibition via glycoprotein (GP) IIb/IIIa receptor antagonists has greatly reduced the need for emergent cardiac surgery. However, this change has come at a cost to both the patient and the cardiac surgical team in terms of increased bleeding risk. Current guidelines for patients requiring coronary artery bypass surgery include: 1) cessation of GP IIb/IIIa inhibitor; 2) delay of surgery for up to 12 h if abciximab, tirofiban, or eptafibitide is used; 3) utilization of ultrafiltration via zero balance technique; 4) maintenance of standard heparin dosing despite elevated bleeding times; and 5) transfusion of platelets as needed, rather than prophylactically. These agents present cardiac surgery teams with increased risk during CABG, although overall risk may be diminished by the substantial benefits to patients with acute coronary syndromes and percutaneous interventions, i.e., reduced infarction rates and improved vessel patency. With judicious planning, urgent coronary artery bypass can be safely performed on patients who have been treated with GP IIb/IIIa receptor inhibitors.

Diagnosis and treatment of heparin-induced thrombocytopenia

Heparin-induced thrombocytopenia (HIT) is a major side effect secondary to the administration of heparin. This syndrome is serious and potentially life threatening. This response is the result of antibodies formed against the platelet factor 4 (PF4)/heparin complex. The incidence of this immune-mediated syndrome has been estimated to be 1-3% of all patients receiving heparin therapy. The occurrence of HIT in patients requiring full anticoagulation for cardiopulmonary bypass (CPB), therefore, presents a serious challenge to the cardiac surgery team. The diagnosis of HIT should be based on both clinical and laboratory evidence. While functional assays, platelet aggregation tests, and the serotonin release assay can be used to support the diagnosis, the negative predictive value of these tests is generally less than 50%. In contrast, although non-functional antibody detection assays are more sensitive, they have a low specificity. HIT can be treated in several ways, including cessation of all heparin and giving an alternative thrombin inhibitor, platelet inhibition followed by heparin infusion, and the use of low molecular weight heparins. In this presentation, the pathology and current diagnostic tests, as well as the successful management of patients with HIT undergoing CPB at New York Presbyterian Hospital, are reviewed.

Blood conservation strategies in cardiac surgery: more is better

OBJECTIVES Recent data show that up to 50% of heart procedures require blood transfusion, which can have adverse long- and short-term outcomes for the patient. This led to the updated 2011 Society of Thoracic Surgery (STS)/Society of Cardiovascular Anesthesiologists (SCA) guidelines in an attempt to adopt more effective blood conservation techniques. We present our results after the implementation of a more aggressive strategy for intraoperative blood conservation in cardiac surgery. METHODS Our cardiac surgery database was reviewed retrospectively, comparing outcomes from two different time periods, after the implementation of a more effective two-way blood conservation strategy beginning in March 2012: more aggressive intraoperative autologous donation (IAD) based on a newly constructed nomogram, and the use of a shorter length circuit of the cardiopulmonary bypass (CPB) which allowed for lower fluid volume as a prime. The method of retrograde autologous priming (RAP) was the same for both time periods. RESULTS A total of 1126 patients (Group 1) were studied in a 12-month period (March 2012-February 2013) after the implementation of the new strategy, and compared with 3758 patients (Group 2) of the previous 36-month period (March 2009-February 2012). There was a significant reduction in the percent change of the intraoperative haematocrit between Groups 1 and 2 (14 vs 28%, P = 0.01), with an increase in the mean IAD volume (655 vs 390 ml, P = 0.02) and a reduction in the CPB priming volume (1000 vs 1600 ml, P = 0.03). Group 1 required significantly less blood transfusions in the perioperative period (29 vs 49%, P = 0.02) and had significantly reduced postoperative rates of respiratory failure (3 vs 7%, P = 0.03), pneumonia (1 vs 3.1%, P = 0.01), chest tube output (350 vs 730 ml, P = 0.01), reoperation for bleeding (1.2 vs 2.5%, P = 0.04) and length of stay (6.1 vs 8.2 days, P = 0.05). CONCLUSIONS Blood conservation is safe and effective in reducing transfusions in cardiac surgery, minimizing perioperative morbidity and mortality. Aggressive IAD and low CPB prime, along with effective RAP, is the three-way blood conservation strategy that leads to improved outcomes in cardiac surgery.

Perfusion method for thoracoabdominal aneurysm repair using the open distal technique

Challenges related to perfusion support of thoracoabdominal aneurysm repair include maintenance of distal aortic perfusion, rapidity of fluid resuscitation, and avoidance of both hypothermia and excessive hemodilution. Using available technology, we have devised a circuit and protocol that addresses these issues. To accomplish such support a bypass circuit consisting of 3/8 inch tubing connected to a centrifugal pump and low-prime heat exchanger was constructed. The circuit was primed via 1/4 inch spiked connectors attached to a 3-liter bag of normal saline. After initial de-airing, the solution was recirculated through this bag. Patients were anticoagulated with 1 mg/kg of heparin prior to initiation of support. Left atrial-descending aorta bypass was used primarily. A cell salvage device was used for autotransfusion. All blood products were delivered via a rapid infusion device. During partial exsanguination, shed blood was not processed, but directed to the rapid infusor for immediate retransfusion. Any packed cells given were washed prior to transfusion. Citrate dextrose solution was used as an anticoagulant for the cell scavenger. This configuration was used successfully in 50 procedures during an 18-month period. Use of this low-prime, custom circuit reduced both hemodilution and cost. A connection off the cell salvage pump offers fast retransfusion of shed blood during partial exsanguination. Minimal heparinization and citrate anticoagulation appears to reduce coagulopathy.

Nonischemic Postoperative Seizure Does Not Increase Mortality After Cardiac Surgery

BACKGROUND Postoperative seizure (PS) is an infrequent, yet distressing, complication after cardiac surgery. We wished to determine the prognostic significance of these complicated neurologic events. METHODS The Weill Cornell Medical College Department of Cardiothoracic Surgery database and the New York State Department of Health Database were reviewed to identify all patients having PS after cardiac surgery between January 1, 2008, and December 31, 2011. RESULTS During the study period 3,518 patients had cardiac surgery at the index hospital; 45 of them had PS (1.27%). Overall, patients having PS had a significant increase in 30-day mortality when compared with those not having PS (6.7% versus 1.5%; p < 0.006). The incidence of major postoperative complications in those having PS was also significantly higher (53.3% versus 10.5%; p < 0.001). However, logistic regression failed to demonstrate PS as an independent predictor of perioperative mortality. When the PS group was further stratified by the presence or absence of cerebrovascular accident, those having both PS and cerebrovascular accident had substantially increased morbidity and mortality (mortality, 0 of 33 versus 3 of 12; major morbidity, 12 of 12 versus 12 of 33; p < 0.01 for both), whereas PS patients without cerebrovascular accident did not have greater risk for either major adverse events or mortality. CONCLUSIONS When PS is associated with acute cerebrovascular accident, a significant increase in postoperative morbidity and mortality can be expected. However, in those with isolated PS (without evidence of new neurologic injury), perioperative mortality and morbidity are comparable to those without any neurologic complications.

eComment. The impact of blood conservation on outcomes in adult cardiac surgery

We read with great interest the study by Vandewiele and associates [1]. Many studies have shown the benefits of retrograde autologous priming (RAP) on preserving the patients haematocrit to levels that do not require transfusion. Only a study by Murphy et al. failed to reproduce similar results in a large cohort of 545 patients [2]. Since our publication in 1998 on retrograde autologous priming [3], we have developed further strategies for blood conservation that have resulted in improved outcomes. Our strategy is three-fold: retrograde autologous priming, low prime volume in the cardiopulmonary bypass (CPB) circuit, and autologous blood donation immediately in the operating room immediately after incision is made. Our preliminary data in the first 300 patients showed a dramatic reduction in the post-operative blood transfusion requirement, with 70% of our patients requiring no blood transfusion at all. In the same time period, our 30-day mortality for all open heart procedures had decreased in an all-time low of 1.38%, and the respiratory complications had dropped from 7% in 2007, to 3% in the end of 2012. This proves that the above three techniques of blood conservation are safe and desirable, leading to reduced morbidity and hospital cost. Conflict of interest: none declared.