Blood Products In Patients Research Articles

Blood transfusion after percutaneous coronary intervention and risk of subsequent adverse outcomes: a systematic review and meta-analysis.

This study sought to define the prevalence and prognostic impact of blood transfusions in contemporary percutaneous coronary intervention (PCI) practice. Although the presence of anemia is associated with adverse outcomes in patients undergoing PCI, the optimal use of blood products in patients undergoing PCI remains controversial. A search of EMBASE and MEDLINE was conducted to identify PCI studies that evaluated blood transfusions and their association with major adverse cardiac events (MACE) and mortality. Two independent reviewers screened the studies for inclusion, and data were extracted from relevant studies. Random effects meta-analysis was used to estimate the risk of adverse outcomes with blood transfusions. Statistical heterogeneity was assessed by considering the I(2) statistic. Nineteen studies that included 2,258,711 patients with more than 54,000 transfusion events were identified (prevalence of blood transfusion 2.3%). Crude mortality rate was 6,435 of 50,979 (12.6%, 8 studies) in patients who received a blood transfusion and 27,061 of 2,266,111 (1.2%, 8 studies) in the remaining patients. Crude MACE rates were 17.4% (8,439 of 48,518) in patients who had a blood transfusion and 3.1% (68,062 of 2,212,730) in the remaining cohort. Meta-analysis demonstrated that blood transfusion was independently associated with an increase in mortality (odds ratio: 3.02, 95% confidence interval: 2.16 to 4.21, I(2) = 91%) and MACE (odds ratio: 3.15, 95% confidence interval: 2.59 to 3.82, I(2) = 81%). Similar observations were recorded in studies that adjusted for baseline hematocrit, anemia, and bleeding. Blood transfusion is independently associated with increased risk of mortality and MACE events. Clinicians should minimize the risk for periprocedural transfusion by using available bleeding-avoidance strategies and avoiding liberal transfusion practices.

Use of blood products in patients with anticoagulant-related major bleeding: an analysis of inhospital outcomes.

The impact of correcting elevated International Normalized Ratio (INR) values on inhospital mortality in patients with warfarin-associated major bleeding is presented. Using patient information from the database of a large U.S. health system, a retrospective analysis was conducted to (1) evaluate inpatient practice patterns in correcting INR elevations among patients hospitalized with warfarin-related intracranial hemorrhage (ICH) or non-ICH bleeding and (2) test the hypothesis that achieving INR correction, defined as an INR of ≤1.5, at any point during the hospital stay is correlated with lower inhospital mortality. Cox proportional hazards models were constructed to assess predictors of inhospital death. Among the 354 patients who met the study selection criteria, INR correction was achieved in 87.9% overall (92.5% and 85.5% of patients with ICH and non-ICH bleeds, respectively). Patients whose elevated INR values were corrected had significantly lower inhospital death rates than those with uncorrected elevations: 15.3% versus 55.6% (p = 0.010) among patients with ICH and 2.0% versus 11.8% (p = 0.017) among those with non-ICH bleeds. After adjusting for baseline demographics and comorbidities, the correlation between failure to correct INR elevations and increased mortality risk was significant only for patients with ICH (hazard ratio, 8.04; 95% confidence interval, 2.07-31.18; p = 0.003). Results of this study indicated that correction of elevated INR values was associated with a lower likelihood of inhospital death among warfarin-treated patients hospitalized for ICH or non-ICH major bleeding.

Thromboelastometry as a supplementary tool for evaluation of hemostasis in severe sepsis and septic shock

Sepsis leads to disruption of hemostasis, making early evaluation of coagulation essential. The aim of this study was to provide a detailed investigation of coagulation and the use of blood products in patients with severe sepsis or septic shock, admitted to a multidisciplinary intensive care unit. Thirty-six patients with severe sepsis or septic shock were included in this prospective observational study. Blood samples and information on transfusion of blood products were obtained for up to 3 consecutive days, and day 7 if the patient was still in the intensive care unit. Thromboelastometry (ROTEM(®)), analyses of thrombin generation, and conventional coagulation tests were performed. ROTEM(®) revealed an overall normo-coagulable state among patients with severe sepsis or septic shock. Conventional coagulation analyses showed divergent results with hypercoagulable trends in terms of reduced antithrombin and acute phase response with increased fibrinogen and fibrin d-dimer, and on the other hand, coagulation disturbances with a decreased prothrombin time and prolonged activated partial thromboplastin time. This hypocoagulabe state was supported by a delayed and reduced thrombin generation. Twelve patients experienced 21 independent transfusion episodes with fresh frozen plasma. Of these, only five (22%) transfusions were performed because of active bleeding. ROTEM(®) demonstrated an overall normo-coagulation, whereas the conventional coagulation tests and thrombin generation analyses mainly reflected hypocoagulation. Given the dynamic and global features of ROTEM(®), this analysis may be a relevant supplementary tool for the assessment of hemostasis in patients with severe sepsis or septic shock.

Thromboelastography (TEG)-based algorithm reduces blood product utilization in patients undergoing VAD implant.

Multiple blood products are often required during and after ventricular assist device (VAD) implants. Generally, transfusion therapy is empirically guided by conventional laboratory tests. In this study, we aimed to compare a thromboelastography (TEG)-based algorithm with a laboratory coagulation test-based algorithm with respect to blood product utilization in patients undergoing VAD implant. From June 2010 to May 2012, a total of 39 consecutive patients underwent VAD implantation. Patients undergoing VAD implant were retrospectively divided into two groups according to transfusion strategy. In the control group (n=20), the need for blood transfusion was based on clinician's discretion according to standard coagulation test results. In the TEG group (n=19), a strict protocol based on TEG parameters was followed for the usage of all perioperative blood products. Coagulation factors, TEG parameters, and blood transfusions were documented and compared between these two groups. There were no differences in demographic variables with the exception of a decreased CPB time in the TEG group (p=0.019). Prothrombin time (PT) (p<0.001) and international normalized ratio (INR) (p<0.001) in the postprotamine interval were significantly higher in the TEG group than in the control group. No significant difference was detected in any coagulation variable in the postoperative (ICU) period between the two groups. Platelet counts decreased in a linear fashion from baseline to the postoperative period in the two groups (p<0.001). Patients in the TEG group received significantly less fresh-frozen plasma in both the intraoperative (p=0.005) and postoperative (p=0.014) periods. Patients in the TEG group also received significantly less platelets both in the postoperative (p=0.03) period and in total amount (p=0.033). There was no difference in consumption of packed red blood cell units between the two groups. Our results show that the strict use of a TEG-guided algorithm significantly reduces the consumption of blood products in patients undergoing VAD implant

Prospective validation of a blood ordering protocol for elective spine arthrodesis and its impact on cost reduction.

Background:On the basis of an institutional audit, the authors published an individual patient-based protocol for preoperative arrangement of blood products in patients undergoing elective spine arthrodesis. The present study was conducted for the prospective validation of the proposed protocol in reducing cross match to transfusion ratio, and its implications on overall cost.Methods:This cross-sectional study was conducted over 1 year (2012). All adult patients who underwent elective spinal arthrodesis were included and prospectively observed. The actual transfusion index was calculated for individual patients with the formula C1/T, where C1 is the number of units of packed RBCs cross matched and T is the number of actual transfusions. C1/T was then compared with a theoretical transfusion index C2/T for the same group of patients, C2 being the number derived from calculating the number of units of packed RBCs that would have been ordered for individual patient according to the protocol. The cost difference between C1/T and C2/T was analyzed.Results:A total of 125 patients were included. A total of 435 units of packed RBCs were ordered (C1), out of which only 108 units were transfused (T), yielding a C1/T of 4.02. The C2 for the same group of patients was 188 units of packed RBCs and the C2/T was thus calculated to be 1.74. Implementation of the protocol would reduce per patient cost from Pakistani Rupees (PKR) 6676.8 ± 4125.8 to 4700.8 ± 1712.86, with a P < 0.001 and an overall reduction of 30%.Conclusion:Cross match to transfusion ratio and blood ordering related cost are both significantly reduced with the application of institutional cross-match protocol.

Is “Intra–operating Room” Thromboelastometry Useful in Liver Transplantation? A Case-Control Study in 303 Patients

Coagulation monitoring during liver transplantation (LT) is, even today, fundamental to reduce blood loss during surgery. Thromboelastometry (TEM) is a proven technique for controlling the various parameters that influence coagulation. However, there are no studies linking “intra–operating room” TEM (orTEM) with LT outcomes. We describe a case-control study in 303 liver graft recipients analyzing variables associated with operative complications and long-term LT outcomes. The results showed that orTEM reduced the use of blood products in patients with Model for End-Stage Liver Disease scores of ≥21, retransplantation, and high surgical difficulty and important intraoperative bleeding. In addition, results in survival and postoperative complications were better when orTEM was used. In conclusion, we confirm that use of orTEM is associated with less use of blood products and a lower rate of complications after LT.

Pediatric preoperative blood ordering: when is a type and screen or crossmatch really needed?

Unnecessary testing for and ordering of blood products adds to overall healthcare costs. Determine intraoperative red blood cell (RBC) product utilization for pediatric procedures and costs associated with perioperative testing and ordering. A retrospective chart review captured perioperative blood testing and intraoperative transfusion data for patients <19 years of age who underwent noncardiac surgery over a 13-month period at one tertiary care hospital. The main outcome measure was cost associated with testing for blood products in patients undergoing procedures that had a zero rate of transfusion. The intraoperative transfusion rate for 8620 noncardiac pediatric procedures was 2.78%. Of 8380 nontransfused patients, 707 (8.4%) had type and screen, and of those, 420 (5%) were crossmatched for RBC products in preparation for surgery. The 10 surgical procedures that had the highest perioperative blood testing but no instances of transfusion were as follows: colostomy or ileostomy takedown, spinal cord untethering, tunneled catheter placement, laparoscopic Nissen fundoplication, elbow reduction and fixation, lumbar puncture, suboccipital craniectomy, hip arthrogram, percutaneous intravascular central line, and tonsillectomy and adenoidectomy. Procedures with low transfusion probability and high crossmatch testing were ventriculoperitoneal shunt revision and growing rod distraction. For all nontransfused patients, the cost of obtaining type and screen was $31,815, and the cost for crossmatch was $25,200. Patients may undergo preoperative type and screen or crossmatch for procedures rarely associated with transfusion. Historic transfusion probability may be used to predict need for transfusion for specific surgical procedures and reduce unnecessary perioperative testing and associated costs.

Effects of Fibrinogen Concentrate as First-line Therapy during Major Aortic Replacement Surgery

Fibrinogen is suggested to play an important role in managing major bleeding. However, clinical evidence regarding the effect of fibrinogen concentrate (derived from human plasma) on transfusion is limited. The authors assessed whether fibrinogen concentrate can reduce blood transfusion when given as intraoperative, targeted, first-line hemostatic therapy in bleeding patients undergoing aortic replacement surgery. In this single-center, prospective, placebo-controlled, double-blind study, patients aged 18 yr or older undergoing elective thoracic or thoracoabdominal aortic replacement surgery involving cardiopulmonary bypass were randomized to fibrinogen concentrate or placebo, administered intraoperatively. Study medication was given if patients had clinically relevant coagulopathic bleeding immediately after removal from cardiopulmonary bypass and completion of surgical hemostasis. Dosing was individualized using the fibrin-based thromboelastometry test. If bleeding continued, a standardized transfusion protocol was followed. Twenty-nine patients in the fibrinogen concentrate group and 32 patients in the placebo group were eligible for the efficacy analysis. During the first 24 h after the administration of study medication, patients in the fibrinogen concentrate group received fewer allogeneic blood components than did patients in the placebo group (median, 2 vs. 13 U; P < 0.001; primary endpoint). Total avoidance of transfusion was achieved in 13 (45%) of 29 patients in the fibrinogen concentrate group, whereas 32 (100%) of 32 patients in the placebo group received transfusion (P < 0.001). There was no observed safety concern with using fibrinogen concentrate during aortic surgery. Hemostatic therapy with fibrinogen concentrate in patients undergoing aortic surgery significantly reduced the transfusion of allogeneic blood products. Larger multicenter studies are necessary to confirm the role of fibrinogen concentrate in the management of perioperative bleeding in patients with life-threatening coagulopathy.

Peri-operative platelet function testing: The potential for reducing ischaemic and bleeding risks

The pivotal role of platelet activation and reactivity during atherothrombotic event occurrence associated with acute coronary syndromes (ACS) or percutaneous coronary interventions (PCI) is well established. Numerous translational research studies have established a threshold level of platelet reactivity during dual antiplatelet therapy above which a higher risk for ischaemic event occurrence has been observed. The clinical validity of these threshold values in reducing ischemic event occurrence with modified P2Y12 receptor therapy is currently under investigation in large-scale clinical trials. The association between on-treatment platelet reactivity measured by an ex vivo assay and the occurrence of bleeding events is less established. Currently, there is limited evidence of an association between platelet inhibition and coronary artery bypass grafting (CABG)- related bleeding in patients on clopidogrel therapy indicating that preoperative platelet function monitoring may guide both the timing of elective CABG and the administration of blood products in patients needing surgery. However, in the absence of a large-scale prospective clinical trial, routine platelet function monitoring and modification of timing of surgery based on platelet function monitoring are currently not recommended.

Clinical Trial Opportunities in Transfusion Medicine: Proceedings of a National Heart, Lung, and Blood Institute State-of-the-Science Symposium

The use of blood products to support patients undergoing the large variety of medical and surgical interventions requiring such support has continued to escalate very significantly over time. Relevantly, significant practice variation in the use of blood products exists among practitioners and institutions, largely because of the lack of robust clinical trial data, in many instances, which are critical for providing practitioners with evidence-based guidelines for appropriate blood product utilization. Recognizing this gap, the National Heart, Lung, and Blood Institute recently established a State-of-the-Science Symposium to help define areas of clinical trial research that would enhance the opportunity for developing appropriate practice guidelines for both Transfusion Medicine and Hemostasis/Thrombosis. Such a Symposium was held in September 2009 to identify important clinical trial research issues in these 2 subject areas of endeavor. The aims of this Symposium were to specifically identify phase 2 and 3 clinical trials that, if conducted over the next 5 to 10 years, could impact the treatment of patients with hemostatic and other disorders as well as to optimize the use of blood products in patients who need such interventions. This article reports on the deliberations that were held relating to the various clinical trial concepts developed by 7 Transfusion Medicine subcommittees. This Symposium generated a rich assortment of clinical trial proposals that will undergo further refinement before final implementation into pilot or full randomized clinical trials. The various proposals identified many opportunities for clinical trial research and most importantly underscored the ongoing need for well-developed evidence-based clinical trial research in the field of Transfusion Medicine.

The need for blood products in patients with crush syndrome

Crush syndrome is typical for multisystem involvement because of coexisting major surgical and/or medical problems. Treatment of patients with crush syndrome following mass disasters is even more problematic as hundreds of patients are admitted to hospitals and need therapy at once. In this study, the authors evaluated the need of blood and blood products in patients hospitalized due to crush syndrome after the Marmara earthquake in a single center The clinical and laboratory variables regarding 60 patients with crush syndrome (30 males and 30 females; mean age: 31.3 +/- 13.8 years) hospitalized at a tertiary center that were documented on the preformed questionnaires distributed by International Society of Nephrology Task Force at the aftermath of the earthquake were analyzed by Statistical Package for Social Sciences for Windows software version 13.0 (SPSS Inc, Chicago, IL, USA). Thirty-nine patients (16 males and 23 females; mean age: 30.1 +/- 12.6 years) were transfused with 589 U of blood, 840 U of fresh frozen plasma, and 172 U of human albumin during the hospitalization. Most of the transfusions were performed during the first week after the hospitalization. As a result, the preparation for disasters should also include logistic plans for obtaining sufficient amount of blood and blood products to be used in the early aftermath of the event.

Transfusion of red blood cells: the impact on short-term and long-term survival after coronary artery bypass grafting, a ten-year follow-up

Transfusion of red blood cells (RBC) and other blood products in patients undergoing coronary artery bypass grafting (CABG) is associated with increased mortality and morbidity. We retrospectively analyzed data of patients who underwent an isolated coronary bypass graft operation between January 1998 and December 2007. Mean follow-up was 1696+/-1026 days, with exclusion of 122 patients lost to follow-up and 80 patients who received 10 units of RBC. Of the remaining patients, 8001 (76.7%) received no RBC, 1621 (15.2%) received 1-2 units of RBC, 593 (5.7%) received 3-5 units and 220 (2.1%) received 6-10 units. The number of transfused RBC was a predictor for early but not for late mortality. When compared to expected survival, survival of patients not receiving any blood product was better, while survival of patients receiving >3 units of RBC was worse. Transfusion of RBC is an independent, dose-dependent risk factor for early mortality after revascularization. Compared to expected survival, receiving no RBC improves patient long-term survival, whereas receiving three or more units of RBC significantly decreases patient survival.

Thromboelastography-Based Transfusion Algorithm Reduces Blood Product Use after Elective CABG: A Prospective Randomized Study

Bleeding and allogeneic transfusion remain constant problems in cardiac surgical procedures. In this study, we aimed to test the role of a routine thromboelastography (TEG)-based algorithm on bleeding and transfusions in patients undergoing elective coronary artery bypass grafting (CABG). Patients (n = 224) undergoing elective CABG with cardiopulmonary bypass were prospectively randomized into two groups according to transfusion strategy: in group 1 (clinician-directed transfusion, n = 110) need for blood transfusion was based on clinician's discretion and standard coagulation tests and in group 2 (TEG algorithm group, n = 114) kaolin-activated (k) TEG-based algorithm-guided perioperative transfusion management. Transfusion, blood loss, and outcome data were recorded. There were no differences in consumption of packed cell units, blood loss, re-exploration for bleeding, and early clinical outcome between the groups. Patients in the TEG group had significantly lower median units of fresh frozen plasma and platelets compared with the other group (p = 0.001). The median number of total allogeneic units transfused (packed cells and blood products) was significantly reduced in the TEG group compared with the other group (median 2, range 1-3 units vs. median 3, range 2-4 units, respectively, p = 0.001). The need for tranexamic acid was significantly diminished in the TEG group compared with the other group (10.3% vs. 19%, respectively, p = 0.007). Our results show that routine use of a kTEG-guided algorithm reduces the consumption of blood products in patients undergoing elective CABG. Adopting such an algorithm into routine management of these patients may help to improve clinical outcome and reduce the potential risks of transfusion-related complications and total costs after CABG.

Multi-modality blood conservation strategy in open-heart surgery: an audit

The objective of this study was to perform an audit of the use of homologous blood and blood products in patients undergoing open-heart surgery by a single surgical team that follows an in-house protocol for blood conservation. The hospital records of 310 consecutive patients (age >15 years) undergoing open-heart surgery over a period of 8 months were retrospectively reviewed to assess the comprehensive blood conservation protocol. Homologous blood and blood product usage during and after surgery, in the intensive care unit and up to hospital discharge was analyzed. Two hundred and fifty-six patients (82.6%) did not receive any blood or blood products. Only 54 patients (17.4%) received one or more units of allogenic transfusion either intraoperatively or postoperatively until discharge. Mean hemoglobin at discharge was 9.8 Grams% (8.9-12 Grams%). A standardized multidisciplinary approach to blood conservation in cardiac surgery decreases bleeding and transfusion requirements in a safe and cost effective manner.

It is Time to Assess the Utility of Thrombelastography in the Administration of Blood Products to the Patient With Traumatic Injuries

Abstract : Jeager and Zimmermann have demonstrated that thrombelastography (TEG) can be conducted rapidly in the emergency department, providing a wide range of information on coagulation status, with data available before conventional laboratory values can be obtained. The use of blood products in patients with trauma is empiric and blind, especially in patients requiring massive transfusion (10 units of packed red blood cells in 24 hours). It is often stated that coagulation status is the most reliable indication of outcome on admission of the patient with traumatic injuries and should be used to direct the transfusion of blood components. Although results from some studies strongly recommend the TEG to define a patient's coagulation status, and potentially direct administration of blood products in patients with trauma, none has yet been sufficiently powered to demonstrate, specifically, how TEG might transform transfusion guidelines. Only a large multicenter study can conclusively demonstrate the effectiveness of rapidly avail- able TEG data and provide the means to develop algorithms to optimally direct blood product use, which in turn, will reduce overall blood product administration and improve outcomes. The work of Jeagar and Zimmermann provides further evidence that such a study of TEG use should be undertaken.

Filter survival time and requirement of blood products in patients with severe sepsis receiving drotrecogin alfa (activated) and requiring renal replacement therapy

IntroductionDrotrecogin alfa (activated) (DrotAA) is licensed in the United States and the European Union for the treatment of severe sepsis with multiple organ failure. Patients with severe sepsis on renal replacement therapy (RRT), who typically receive additional anticoagulation to prevent circuit clotting, may be at higher risk of bleeding when DrotAA is administered in addition to standard anticoagulation. However, the effects of DrotAA on filter duration in the absence of additional anticoagulation have not been established. The aim of this study was to analyse the filter survival time (FST), and to quantify the requirement of packed red cells (PRC) and blood products during DrotAA infusion.MethodsThis was a single-centre, retrospective observational study conducted in an adult intensive care unit (ICU). Thirty-five patients with severe sepsis who had received both RRT and DrotAA were identified, and all relevant clinical and laboratory data were retrieved from the departmental electronic patient record. We compared haemofilter parameters, requirement of blood products and haemodynamic data recorded during RRT and the infusion of DrotAA with those recorded on RRT with standard anticoagulation after the DrotAA infusion had been completed (post-DrotAA).ResultsThe proportion of filter changes due to filter clotting was similar during DrotAA infusion and with conventional anticoagulation post-DrotAA infusion. There was no difference in the FST and filter parameters during DrotAA in the presence or absence of additional anticoagulation with heparin or epoprostenol. A similar proportion of patients required red cell transfusion, although a greater proportion of patients received platelet and fresh frozen plasma during DrotAA infusion compared with the post-DrotAA period with no difference between medical and surgical patients.ConclusionsAdditional anticoagulation during DrotAA infusion does not appear to improve FST. The use of DrotAA in patients with severe sepsis requiring RRT is safe and is not associated with an increased need for PRC transfusion or major bleeding events.

Use of Blood Products in Patients Treated Surgically for Stage I Non-Small Cell Lung Cancer

Retrospective study on the relation between the use of blood products and survival rates in patients treated surgically for stage I non-small cell lung cancer (NSCLC). The study included 856 patients who underwent surgical resection from 1969 to 2000 for stage I NSCLC, classified histologically according to the current guidelines of the Spanish Society of Pulmonary and Thoracic Surgery (SEPAR). Patients who died in the postoperative period were excluded from the study. A series of clinicopathological variables were recorded, including the perioperative use or not of blood products. Descriptive, univariate, and multivariate statistical analyses were performed. Follow up concluded in December of 2003. One hundred twenty-five patients (14.6%) underwent a perioperative transfusion. A significant association was found between the use of blood products and tumor size (P<.001), pneumectomy (P<.001), and cell type (P<.05). The respective 2, 5, and 10-year survival rates were 78%, 63%, and 54% for the nontransfusion group, and 73%, 59%, and 46% for the transfusion group. Both survival curves were compared and no significant differences were found (P=.23). Multivariate regression analysis included tumor size, patient age, and histologic cell type (squamous cell carcinoma or not); no relation between transfusion and survival was found. In our series, we found no difference in survival rates for patients with stage I NSCLC after perioperative blood transfusion.

Does Acute Normovolemic Hemodilution Work in Cardiac Surgery?

University Hospital of Geneva, Switzerland. denis.morel@hcuge.chIn Reply:—We appreciate the interest of Moskowitz et al . regarding our article. 1They hypothesize that too restrictive inclusion criteria and excessive fluid replacement in the acute normovolemic hemodilution (ANH) group could explain the absence of beneficial effects of ANH.First, for obvious ethical reasons, we selected patients to undergo preoperative ANH based on the recommendations of the British Committee for Standards in Blood Transfusion, which take into account the potential risks and benefits of blood salvage techniques. Therefore, due to the risk of myocardial ischemia, stroke, or heart failure, we did not perform ANH in patients with severe coronary artery disease (recent myocardial infarction, unstable angina, left main coronary stenosis), severe aortic stenosis, poor left ventricular function, carotid stenosis, and/or preoperative anemia. According to these stringent exclusion criteria, we included only 57% of all consecutive patients undergoing elective coronary revascularization or valvular surgery. Nevertheless, a high risk of bleeding was considered in more than 50% of these surgical candidates (preoperative anticoagulant and/or aspirin therapy, repeat or combined operation) in whom the blood-sparing benefits of ANH could be anticipated.Second, perioperative fluid hydration was similar in both groups, except for compensation of the removed blood by colloids in the ANH group: the volumes of infused crystalloids (94.6 ml · kg−1· 24 h−1and 88.8 ml · kg−1· 24 h−1in the control and ANH groups, respectively) and colloids (16.5 ml · kg−1· 24 h−1and 26.2 ml · kg−1· 24 h−1in the control and ANH groups, respectively) were in the range of the values commonly reported 2and included any solution administered intravenously and through the cardiopulmonary bypass (e.g. , cardioplegia, priming). To achieve similar cardiac preload conditions, larger than expected volume of colloids were given in the ANH group (hypervolemic compensation), which resulted in ANH-induced vasodilatation and reduced blood viscosity. 3Since ANH is known to be associated with poor tolerance to acute blood loss and impaired adrenergic response, 4,5we closely guided fluid administration using transesophageal echocardiography and central venous pressure monitoring in order to avoid hypovolemia and to detect myocardial ischemia.Finally, as suggested by Dr. Moskowitz and others, 6we agree that the implementation of a standardized, multidisciplinary approach, including definition of transfusion criteria, administration of antifibrinolytic drugs, use of cell saver devices, and external heating, is most helpful to reduce transfusion of allogenic blood products in patients undergoing cardiac surgery. However, evidence supporting the addition of ANH as a blood-sparing technique is still lacking, although a consensus is based on data from observational studies and prospective, unblinded, randomized trials. 7

Hemostatic drugs in trauma and orthopedic practice

a naturally occurring serine protease inhibitor, is found in the mast cells of all mammalian species as well as many lower orders of life. Unfortunately, at this time, we do not understand the true physiological role of aprotinin in nature. What is known is that the use of high doses of the drug inhibits a number of the inflammatory processes involved with open heart surgery and also modifies the hemostatic system to allow reductions in bleeding and thus the need for blood and blood products. The use of high-dose aprotinin therapy followed reports of the potential benefit of this approach in patients following trauma. 1 Largedose aprotinin therapy has been shown to be extremely effective and safe in preventing blood loss and the need for blood and blood products in patients undergoing open heart surgery. The current literature contains more than 40 reports of randomized placebo-controlled studies 2'3 showing that lfigh-dose aprotinin therapy reduced drain losses (range, 35% to 81%), the total amount of transfusions (range, 35% to 97%), and the proportion of patients requiring transfusions of blood or blood products (range, 40% to 88%). Since the first description of the hemostatic actions of high-dose aprotinin therapy in patients undergoing reoperation 4 or high-risk cardiac procedures, this agent has been the standard of care in this situation and is the only product licensed for use for this indication in North America. The aim of this article is to discuss the potential for the anti-inflammatory and hemostatic action to benefit patients undergoing elective orthopedic and trauma surgery and also following trauma itself. The article is divided into three sections: (1) the use of drugs to prevent bleeding during elective

A cohort study of coagulation parameters and the use of blood products in surgery of the thoracic and thoracoabdominal aorta

Objectives: We sought to study the hemostatic profile and the use of blood products in patients undergoing thoracic and thoracoabdominal aortic aneurysm repair. Methods: This is a cohort study comparing three groups of patients: 7 undergoing elective acute normovolemic hemodilution (ANH); 15 undergoing elective procedures without ANH (non-ANH); and 8 undergoing repair of ruptured thoracoabdominal aneurysms. A control group of 10 patients was used for comparison of preoperative hemostasis. The parameters studied were platelet concentration, partial thromboplastin time (PTT), and international normalized ratio (before and after surgery), packed red blood cells, fresh frozen plasma, platelets, cryoprecipitates, donor exposure, and use of desmopressin and epsilon-aminocaproic acid. Analysis of variance and multiple stepwise regression analysis were used. Results: Before operation the patients with aneurysms had PTTs prolonged compared with control subjects (P <.05). After operation the ANH group had higher platelet counts than the ruptured group (P =.001) and higher platelet counts (P =.05) and lower PTTs (P =.001) than the non-ANH group. The ANH group was transfused fewer platelets than the non-ANH group (P =.001) and less of every blood product than the ruptured group (P =.05); statistically significant differences were not observed for packed red blood cells, fresh frozen plasma, or platelets. The ANH group was exposed to an average of 65 donors fewer than the ruptured group (P <.001) and 34 fewer than the non-ANH group (P <.05). These differences could not be explained by baseline coagulation status or by the intraoperative use of desmopressin or epsilon-aminocaproic acid. Conclusions: The coagulation abnormality identified before surgery is that of higher PTT values, suggesting a disturbance of the extrinsic coagulation pathway. Blood losses, donor exposure, and platelet use were highest in the ruptured group and lowest in the ANH group. After surgery the ruptured group exhibited the worst coagulation parameters, and the ANH group exhibited the best with higher platelet count and lower PTT values than the other groups. The ANH technique appears to be an useful adjunct in the anesthetic management of these patients. (J Vasc Surg 2001;33:462-8.)