Transfusion practice in coronary artery bypass surgery in Denmark: a multicenter audit

Transfusion rates in coronary artery bypass grafting (CABG) continue to vary substantially, although guidelines for allogeneic transfusion have been developed. In order to evaluate ongoing transfusion practices, we performed a multicenter audit in four Danish hospitals regarding the use of allogeneic blood products among patients undergoing first-time CABG. Data on patient characteristics, peri- and postoperative factors were retrieved from 600 patient records (150 records per hospital). Substantial differences were seen regarding preoperative intake of antiplatelet drugs, perioperative use of antifibrinolytic drugs, use of cardiopulmonary bypass (CPB), cross-clamp time, time on CPB, lowest hemoglobin during CPB, and number of distal anastomoses. The percentage of patients transfused with allogeneic red blood cells ranged from 30.0% to 64.2%. Several patients (12.1-42.7%) transfused with red blood cells were discharged with a hemoglobin concentration >7 mmol/l, indicating inappropriate transfusions. The relative risk of receiving an allogeneic blood transfusion was 2.1 (95% CI: 1.6-2.7) in the hospital with the highest transfusion rate, after adjustment for patient-, drug-, and procedure-related factors. Interesting differences in transfusion rates exists in Danish hospitals and these differences may reflect true variations in transfusion practices. Audits create a basis for educational efforts among surgeons and anesthesiologists to standardize transfusion practices.     

Utilization of preoperative autologous blood donation in elective surgery

Background: The aim of the present paper was to review the pattern of collection and transfusion of autologous red cells for elective surgical procedures Methods: Data on requests for preoperative autologous donation of blood were obtained from the Australian Red Cross Blood Service, Victoria and the Royal Melbourne Hospital for the calendar year 1998. The following information was collected: patient age, sex, surgery type, number of autologous units requested and collected and, if relevant, reasons for not achieving the requested collection. Transfusion of autologous units and any additional homologous units was confirmed from records at the blood banks of the Royal Melbourne Hospital and Melbourne Pathology (the pathology provider performing cross‐matching for the majority of autologous units collected by Australian Red Cross Blood Service, Victoria). Results: Over 12 months, 2803 units of autologous blood were requested and 2282 units collected from 1301 patients. The most common reason for failure to collect the number of units requested was insufficient time between referral and surgery. Of the autologous units collected, 73% were transfused giving a collection to transfusion ratio of 1.4. Sixty‐eight per cent of patients received their autologous units only, 10% received both autologous and homologous units, while 22% were not transfused. For the majority of procedures, patients using preoperative autologous donation of blood had higher transfusion rates than those who did not use this. Conclusions: Ninety per cent of patients undergoing preoperative autologous donation of blood successfully avoided homologous blood exposure. However, preoperative autologous donation of blood is both wasteful and increases the incidence of transfusion in surgical procedures.     

Use of red blood cell transfusions in surgery

Background: Limited blood supplies necessitate the rational use of blood products. The aim of the present study was to provide a basis for audits of red cell usage in surgery by benchmarking common practice. Application of the data to the construction of a maximum surgical blood order schedule may be relevant for centres that perform a serological crossmatch or who collect autologous units. Methods: Data on surgical procedures identified by Commonwealth Medical Benefits Schedule item numbers, were collected retro­spectively from theatre and blood bank records at the Royal Melbourne and Melbourne Private hospitals from May 1997 to April 1998. The percentage of procedures for which red cells were transfused, and the mean, median and range of units transfused for procedures with ≥ 30% transfusion likelihood were identified. Results: Over 12 months, 266 surgical procedure codes were itemized ≥ 10 times each, contributing 12 300 data entries. Only 38 procedures demonstrated an incidence of transfusion of at least 30%. Most frequently transfused procedures included spinal fusion, total hip replacement, mandible/maxilla resection, prostatectomy and bladder excision. Conclusion: The number of common surgical procedures in which there is a 30% or greater likelihood that red cell transfusions will be given is limited. This benchmarking of common red cell usage is a first step in the process of determination of transfusion appropriateness.     

Autotransfusion of washed shed mediastinal fluid decreases the requirement for autologous blood transfusion following cardiac surgery: a prospective randomized trial

Objectives: The National Blood Service issues 2.2 million units of blood per year, 10% of these (220 000) are utilized in cardiac procedures. Transfusion reactions, infection risk and cost should stimulate us to decrease this transfusion rate. We test the efficacy of autotransfusion following surgery in a prospective randomized trial. Methods: One hundred and twelve patients undergoing CABG, valve or CABG+valve procedures were randomized into two groups. Group A received washed postoperative drainage fluid and group C were controls. The indication for transfusion was a postoperative haemoglobin (Hb) <10 g/l or a PCV<30. There was no significant difference in preoperative and operative variables between the groups. Results: Twenty-eight patients in group A and 46 in group C required homologous transfusion (P=0.0008). Group A patients required 298±49 ml of banked blood per patient, group C 508±49 ml (P=0.003). There was no difference in total blood required (volume autotransfused+volume banked blood transfused) between the groups (group A 404±50 ml, group C 508±50 ml) or in mean total mediastinal fluid drainage (group A 652±51 ml, group C 686±50ml). The mean Hb concentration was significantly higher in group A on day 1 (11.2 g/dl±51 vs.10.6 g/dl±13 (P=0.002)). No morbidity was associated with autotransfusion. Conclusion: Autotransfusion can decrease the amount of homologous blood transfused following cardiac surgery. This represents a benefit to the patient and a decrease in cost to the health service.     

Transfusion of red blood cells: no impact on length of hospital stay in moderately anaemic parturients

BACKGROUND: In a search for information to improve decision making on red blood cell (RBC) transfusion, we examined the impact of RBC transfusion on the length of hospital stay for delivery in moderately anaemic women (haemoglobin, 7-10 g/dl). METHODS: This was a retrospective, observational study covering 2 years (2002 and 2003), and included major blood-transfusing hospitals from four university and five central hospital districts managing 67.5% of Finnish in-hospital deliveries. The impact of the transfusion of 1-2 RBC units vs. no transfusion on the length of hospital stay was evaluated for three different haemoglobin levels: 7-7.9, 8-8.9 and 9-10 g/dl. RESULTS: Of the 1954 moderately anaemic mothers in hospital for delivery, 13.3% were transfused with RBC. The mean length of hospital stay was 5.2 days vs. the average Finnish hospital delivery stay of 3.5 days. No differences in stay were found between patients with comparable anaemia transfused with 1-2 RBC units or none (at the three haemoglobin levels: P= 0.50, P= 0.07 and P= 0.54, respectively). The final haemoglobin value was higher (P < 0.001) in transfused patients. CONCLUSION: The duration of admission for delivery in moderately anaemic parturients was longer than the average length of hospital stay in Finnish parturients. However, 1-2 RBC units had no impact on the length of stay, suggesting that unnecessary RBCs are transfused after delivery. Thus, transfusion practices in obstetrics are not always optimal.     

Effect of peri-operative red blood cell transfusion on 30-day and 1-year mortality following coronary artery bypass surgery.

OBJECTIVE: The purpose of this study was to examine the effect of peri-operative red blood cell (RBC) transfusion on 30-day and 1-year mortality following coronary artery bypass grafting (CABG). METHODS: We retrospectively analysed 3024 consecutive patients who underwent isolated CABG between January 1999 and December 2001. Patient records were linked to the National Strategic Tracing Service, which records all mortality in the UK. Thirty-day and 1-year mortality were derived from Kaplan-Meier curves. Confounding variables were controlled for by constructing a propensity score for the probability of receiving a transfusion from core patient characteristics including the lowest recorded laboratory haemoglobin (LL Hb) from a clinical chemistry database (C statistic 0.81). The propensity score and the comparison variable (transfusion versus no transfusion) were included in a Cox proportional hazards analysis, allowing calculation of adjusted hazard ratios (HR) and Kaplan-Meier survival curves. RESULTS: Nine hundred and forty (31.1%) patients received RBC transfusion during or within 72h of surgery. Predictors of the need for transfusion were LL Hb and lower body mass index, use of cardiopulmonary bypass, female sex, number of grafts, renal dysfunction, increased age, extent of disease, and prior CABG; these factors were all included in the propensity score. After 1-year of follow-up, 122 (4.03%) deaths occurred. The crude HR for 1-year mortality in patients transfused was 3.0 (P<0.001). After adjusting for the propensity score, re-operation for bleeding, peri-operative blood loss and post-operative complications, the adjusted 30-day mortality was 1.9% in transfused patients compared to 1.1% in patients not transfused (P<0.05). The adjusted HR for 1-year mortality in patients transfused was 1.88 (P<0.01). CONCLUSIONS: Peri-operative RBC transfusion after CABG is associated with an increased risk of mortality during a 1-year follow-up period, with a large proportion of deaths occurring within 30-days.     

National Comparative Audit of Blood Use in Elective Primary Unilateral Total Hip Replacement Surgery in the UK

INTRODUCTION

Blood is a scarce and expensive product. Although it may be life-saving, in recent years there has been an increased emphasis on the potential hazards of transfusion as well as evidence supporting the use of lower transfusion thresholds. Orthopaedic surgery accounts for some 10% of transfused red blood cells and evidence suggests that there is considerable variation in transfusion practice.

PATIENTS AND METHODS

NHS Blood and Transplant, in collaboration with the Royal College of Physicians, undertook a national audit on transfusion practice. Each hospital was asked to provide information relating to 40 consecutive patients undergoing elective, primary unilateral total hip replacement surgery. The results were compared to indicators and standards.

RESULTS

Information was analysed relating to 7465 operations performed in 223 hospitals. Almost all hospitals had a system for referring abnormal pre-operative blood results to a doctor and 73% performed a group-and-save rather than a cross-match before surgery. Of hospitals, 47% had a transfusion policy. In 73%, the policy recommended a transfusion threshold at a haemoglobin concentration of 8 g/dl or less. There was a wide variation in transfusion rate among hospitals. Of patients, 15% had a haemoglobin concentration less than 12 g/dl recorded in the 28 days before surgery and 57% of these patients were transfused compared to 20% with higher pre-operative values. Of those who were transfused, 7% were given a single unit and 67% two units. Of patients transfused two or more units during days 1–14 after surgery, 65% had a post transfusion haemoglobin concentration of 10 g/dl or more.

CONCLUSIONS

Pre-operative anaemia, lack of availability of transfusion protocols and use of different thresholds for transfusion may have contributed to the wide variation in transfusion rate. Effective measures to identify and correct pre-operative anaemia may decrease the need for transfusion. A consistent, evidence-based, transfusion threshold should be used and transfusion of more than one unit should only be given if essential to maintain haemoglobin concentrations above this threshold.     

Institutional variability in red blood cell conservation practices for coronary artery bypass graft surgery. Institutions of the MultiCenter Study of Perioperative Ischemia Research Group

OBJECTIVE: To assess whether substantial institutional variability exists in red blood cell conservation practices associated with coronary artery bypass graft (CABG) surgery. DESIGN: Prospective, randomized patient enrollment and data collection. SETTING: Twenty-four U.S. academic institutions participating in the Multicenter Study of Perioperative Ischemia. PARTICIPANTS: A well-defined subset of primary CABG surgery patients (n = 713) expected to be at low risk for bleeding and exposure to allogeneic transfusion. INTERVENTIONS: None (observational study). MEASUREMENTS AND MAIN RESULTS: Frequency of use of red blood cell conservation techniques was determined among institutions. Correlation was determined between use of each technique and transfusion of allogeneic red blood cells and between use of each technique and median institutional blood loss. Significant variability (p < 0.01) was detected in institutional transfusion practice with respect to the use of predonated autologous whole blood, normovolemic hemodilution, red cell salvage, and reinfusion of shed mediastinal blood. The frequency of institutional use of these techniques was not associated with allogeneic transfusion (r2 < 0.15) or blood loss (r2 < 0.10) in the low-risk population of patients examined. CONCLUSIONS: Institutions vary significantly in perioperative blood conservation practices for CABG surgery. Further study to determine the appropriate use of these techniques is warranted.     

Perflubron emulsion (AF0144) augments harvesting of autologous blood: a phase II study in cardiac surgery

OBJECTIVE: To assess tolerance and preliminary efficacy of a perfluorocarbon emulsion (AF0144) used with acute normovolemic hemodilution to reduce allogeneic blood transfusion for patients undergoing coronary artery bypass graft (CABG) surgery with cardiopulmonary bypass (CPB). DESIGN: Controlled, single-blind, parallel-group phase II dose escalation trial. SETTING: Single-institution university medical center. PARTICIPANTS: Adult patients undergoing elective CABG surgery (n = 36). INTERVENTIONS: A calculated volume of autologous whole blood was harvested for each patient with a target on-bypass hematocrit of 20% to 22%. Placebo, low-dose (1.8 g/kg) AF0144, or high-dose (2.7 g/kg) AF0144 was infused. During CPB, blood was transfused at protocol-defined triggers (hematocrit <15%, PvO(2) <30 mmHg, SvO(2) <60%). After CPB, all autologous whole blood was reinfused. Allogeneic red blood cells were transfused if a trigger was reached. MEASUREMENTS AND MAIN RESULTS: Safety assessments (vital signs, hematology, blood chemistry, coagulation, and adverse events) were monitored through postoperative day 21. Efficacy endpoints included percentage of patients reaching a transfusion trigger and number of allogeneic units of red blood cells transfused. During CPB, <25% of subjects reached a transfusion trigger. During hospitalization, significantly fewer (p < 0.01) high-dose subjects (33%) reached a trigger than did control patients (91%). Allogeneic red blood cell transfusion did not differ significantly among groups. Safety assessments indicated AF0144 was well tolerated. CONCLUSION: The data suggest that AF0144 when used with acute normovolemic hemodilution is well tolerated and may be effective when used to enhance oxygen delivery for patients undergoing CABG surgery. Confirmation of safety and efficacy in a larger phase III clinical trial is warranted.     

Red blood cell transfusion following burn

A severe burn will significantly alter haematologic parameters, and manifest as anaemia, which is commonly found in patients with greater than 10% total body surface area (TBSA) involvement. Maintaining haemoglobin and haematocrit levels with blood transfusion has been the gold standard for the treatment of anaemia for many years. While there is no consensus on when to transfuse, an increasing number of authors have expressed that less blood products should be transfused. Current transfusion protocols use a specific level of haemoglobin or haematocrit, which dictates when to transfuse packed red blood cells (PRBCs). This level is known as the trigger. There is no one 'common trigger' as values range from 6 g dl(-1) to 8 g dl(-1) of haemoglobin. The aim of this study was to analyse the current status of red blood cell (RBC) transfusions in the treatment of burn patients, and address new information regarding burn and blood transfusion management. Analysis of existing transfusion literature confirms that individual burn centres transfuse at a lower trigger than in previous years. The quest for a universal transfusion trigger should be abandoned. All RBC transfusions should be tailored to the patient's blood volume status, acuity of blood loss and ongoing perfusion requirements. We also focus on the prevention of unnecessary transfusion as well as techniques to minimise blood loss, optimise red cell production and determine when transfusion is appropriate.     

Effects of cell saver autologous blood transfusion on blood loss and homologous blood transfusion requirements in patients undergoing cardiac surgery on- versus off-cardiopulmonary bypass: a randomised trial.

OBJECTIVE: Off-pump CABG is potentially associated with reduced intraoperative blood loss and homologous blood transfusion in comparison to on-pump CABG. In this randomised controlled study we investigated the effects of autologous cell saver blood transfusion on blood loss and homologous blood transfusion requirements in patients undergoing CABG on- versus off-CPB. METHODS: Eighty patients were randomised into one of four groups: (A) on-CPB with cell saver blood transfusion (CSBT), (B) on-CPB without CSBT, (C) off-pump with CSBT and (D) off-pump without CSBT. Volume of intraoperative autologous blood transfusion, postoperative mediastinal blood loss and homologous blood transfusion requirements were measured. Homologous blood was transfused when haemoglobin concentration fell below 8 g/dl postoperatively. Pre- and postoperatively prothrombin time and partial thromboplastin time were measured. RESULTS: Preoperative patient characteristics were well matched among the four groups. The amount of salvaged mediastinal blood available for autologous transfusion was significantly higher in the on-pump group (A) compared to the off-CPB group (C) (433+/-155 ml vs 271+/-144 ml, P=0.001). Volume of homologous blood transfusion was significantly higher in group B vs groups A, C and D (595+/-438 ml vs 179+/-214, 141+/-183 and 230+/-240 ml, respectively, P<0.005). The cell saver groups (A and C) received significantly less homologous blood than the groups without cell saver (160+/-197 ml vs 413+/-394 ml, respectively, P<0.005). Patients undergoing off-CPB surgery received significantly less homologous blood than those undergoing on-CPB CABG irrespective of cell saver blood transfusion (184+/-214 ml vs 382+/-397 ml, P<0.05). Postoperative blood loss was similar in the four groups (842+/-276, 1023+/-291, 869+/-286 and 903+/-315 ml in groups A to D, respectively, P>0.05). Clotting test results revealed no significant difference between the groups. There was no significant difference in postoperative morbidity between groups. CONCLUSION: Off-pump CABG is associated with significant reduction in intraoperative mediastinal blood loss and homologous transfusion requirements. Autologous transfusion of salvaged washed mediastinal blood reduced homologous transfusion significantly in the on-CPB group. Cell saver caused no significant adverse impact on coagulation parameters in on- or off-CPB CABG. Postoperative morbidity and blood loss were not affected by the use of CPB or autologous blood transfusion. We recommend the use of autologous blood transfusion in both on- and off-pump CABG surgery.     

Frequency of homologous blood transfusion in patients undergoing cleft lip and palate surgery

Aim:

The study aims to determine the frequency of homologous blood transfusion in patientsundergoing cleft lip and palate surgery at the Lagos University Teaching Hospital, Nigeria.

Setting and Design:

A prospective study of transfusion rate in cleft surgery conducted at the Lagos University Teaching Hospital, Nigeria.

Material and Methods:

One hundred consecutive patients who required cleft lip and palate surgery were recruited into the study. Data collected included age, sex and weight of patients, type of cleft defects, type of surgery done, preoperative haematocrit, duration of surgery, amount of blood loss during surgery, the number of units of blood cross-matched and those used. Each patient was made to donate a unit of homologous blood prior to surgery.

Results:

There were 52 females and 48 males with a mean age of 64.4 ± 101.1 months (range, 3-420 months). The most common cleft defect was isolated cleft palate (45%) followed by unilateral cleft lip (28%). Cleft palate repair was the most common procedure (45%) followed by unilateral cleft lip repair (41%). The mean estimated blood loss was 95.8 ± 144.9 ml (range, 2-800ml). Ten (10%) patients (CL=2; CP=5, BCL=1; CLP=2) were transfused but only two of these were deemed appropriate based on percentage blood volume loss. The mean blood transfused was 131.5 ± 135.4ml (range, 35-500ml). Six (60%) of those transfused had a preoperative PCV of < 30%. Only 4.9% of patients who had unilateral cleft lip surgery were transfused as compared with 50% for CLP surgery, 11% for CP surgery, and 10% for bilateral cleft lip surgery.

Conclusions:

The frequency of blood transfusion in cleft lip and palate surgery was 10% with a cross-match: transfusion ratio of 10 and transfusion index of 0.1. A "type and screen" policy is advocated for cleft lip and palate surgery.     

Cross‐matched blood in colorectal surgery: a clinical waste?

Aim This study was carried out to determine the rate of perioperative blood transfusion and to create an evidence‐based approach to requesting blood for elective colorectal surgery. Method A comparative cohort study was carried out of 164 patients (107 men, 57 women, median age 68 years) who underwent major colorectal surgery. Details obtained included demographic and operative information, the number of units of blood cross‐matched, units used, the reasons for transfusion and patient suitability for electronic issue (EI). The cross‐match to transfusion ratio (C:T ratio) was calculated for each procedure and for the whole group of colorectal procedures. Results Some 162 units of blood were cross‐matched for 76 (46%) patients, with the remaining 88 (54%) being grouped with serum saved. Twenty‐one (13%) were transfused with a total of 48 units of blood. The C:T ratio for all procedures was 3.4/1. The commonest indication for transfusion was anaemia. One patient required an emergency transfusion. The majority (78%) of patients were suitable for EI. There were no significant differences between the transfused and nontransfused groups with regard to age, diagnosis (malignant vs benign) and laparoscopic or open colorectal procedure. Conclusion Only a small proportion of patients undergoing elective major colorectal surgery require perioperative blood transfusions, most of which are nonurgent. Blood should not be routinely cross‐matched in patients who are suitable for EI.     

Massive blood transfusion and trauma resuscitation

AIMS: To review the massive transfusion practice at a Level I adult Trauma Centre during initial trauma reception and resuscitation. METHODS: All trauma patients presenting to The Alfred Emergency & Trauma Centre and receiving a transfusion of five units or more of packed red blood cells within 4h of presentation over a 26-month period were included in this study. Patient demographics, clinical characteristics, injuries, surgical management and volume of blood transfused were analysed with mortality as the primary endpoint. Initial clinical features and injuries predictive of massive transfusion were also analysed. RESULTS: There were 119 patients who received a transfusion of five units or more of packed red blood cells (PRBCs) within 4h of presentation. The median Injury Severity Score of this group of patients was 34.0 (IQR 26-48) and mortality was 27.7%. The median number of packed red blood cell transfused was 8.0 (IQR 6-14) in the 1st 4h. Initial clinical features and injuries independently associated with a larger volume of blood transfused were initial hypotension, fractures of the pelvis, kidney injuries, initial acidaemia, and thrombocytopaenia. The Injury Severity Score, initial coagulopathy measured by APTT and the presence of head injuries were the independent predictors of mortality. CONCLUSIONS: The volume of blood transfused during trauma resuscitation was not found to be an independent predictor of mortality. Prospective studies into transfusion practice and clinical features of patients during the trauma resuscitation phase requiring massive transfusion are needed to establish evidence-based guidelines for massive transfusion.     

The effect of acute normovolemic hemodilution on homologous blood requirements and total estimated red blood cell volume lost

Background: Acute normovolemic hernodilution combined with retransfusion is one of the various techniques proposed to avoid homologous blood transfusion in cardiac surgery. The purpose of the present paper is to study the effect of the volume of autologous blood collected pre-cardiopulmonary bypass (CPB) on homologous blood requirements and total estimated red blood cell (RBC) volume lost in coronary artery bypass grafting (CABG) surgery.
Methods: Following induction of anesthesia, sequestration of one (5–8 ml/kg; Group I, n=14) or two units (12–15 ml/kg; Group 11, n=14) of fresh autologous blood was performed under electrocardiographic and hernodynamic control. Group III (n= 14) was designated as the control group. Autologous blood was reinfused at the conclusion of CPB.
Results: The use of homologous blood in the study groups was significantly less than in the control group. High-volume phlebotomy did not make a significant difference in the requirement of the homologous blood, while causing a mild increase in the total estimated RBC volume lost. No significant differences could be demonstrated in preoperative, post-CPB and discharge hematocrit levels and postoperative blood drainage between the groups.
Conclusion: Acute intraoperative hemodilution with high- and low-volume phlebotomy reduced the homologous blood requirements similarly regardless of the amount of phlebotomy.     

Blood transfusion in patients having caesarean section: a prospective multicentre observational study of practice in three Pakistan hospitals

BackgroundIncreasing awareness of the risks of blood transfusion has prompted examination of red cell transfusion practice in obstetrics. A six-month prospective observational study was performed to examine blood transfusion practices in patients undergoing caesarean delivery at three hospitals in Pakistan.MethodsIn the three hospitals (two private, one public) 3438 caesarean deliveries were performed in the study period. Data were collected on patient demographics, indications for transfusion, ordering physicians, consent, associations with obstetric factors, estimated allowable blood loss, calculated blood loss, pre- and post-transfusion haemoglobin and discharge haemoglobin.ResultsA total number of 397 (11.5%) patients who underwent caesarean section received a blood transfusion. The highest transfusion rate of 16% was recorded in the public tertiary care hospital compared to 5% in the two private hospitals. Emergency caesarean delivery and multiparity were associated with blood transfusion (P < 0.05). More emergency caesarean sections were performed in the public compared to the private hospitals (85.4% vs. 41.6%). More multiparous patients underwent caesarean section in the public hospital (57.8% vs. 40.4%). Attending physicians took the decision for transfusion in 98% of cases. In 343 (86%) patients, blood transfusion was given even when the haemoglobin was >7 g/dL. The method for documenting the indication or consent for transfusion was not found in any of the three hospitals.ConclusionBlood transfusion was prescribed more readily in the public hospital. Identification of a transfusion trigger and the development of institutional guidelines to reduce unnecessary transfusion are required.     

Impact of autotransfusion after coronary artery bypass grafting on oxygen transport

Background: Autotransfusion of shed mediastinal blood after coronary artery bypass grafting (CABG) has been shown to reduce the requirement for allogeneic blood. We have previously demonstrated in non-randomized studies that the oxygen capacity of shed mediastinal blood is similar to the patient's circulating blood and better than stored allogeneic blood. Therefore, we wanted to examine the influence of autotransfusion of shed mediastinal blood on oxygen transport capacity in patients undergoing CABG.
Methods: A prospective, randomized, controlled study involving 120 patients having elective, uncomplicated CABG was performed. The autotransfusion group received transfusion of shed mediastinal blood for 18 h. Both groups received allogeneic red cells if their hemoglobin concentration decreased below 5 mmol/L. Red blood cell 2, 3-diphosphoglycerate (2, 3-DPG) was measured preoperatively and at intervals up to the hospital discharged. Hemodynamic measurements as well as blood gas and hemoglobin measurements from samples of arterial and mixed venous blood were used for calculation of oxygen transport capacity.
Results: During the autotransfusion period only 2 patients (4%) in the autotransfusion group required allogeneic blood compared to 11 patients (20%) in the control group. The 2, 3-DPG levels in the autotransfusion group were unchanged before and after autotransfusion (4.4 vs. 4.3 umol/ml erythrocyte). In the control group, 2, 3-DPG levels decreased from 4.3 to 3.9 umol/ ml erythrocyte during the same period. There were no differences in the other measured parameters for oxygen transport capacity between the groups.
Conclusion: Autotransfusion of shed mediastinal blood conserves the 2, 3-DPG level of the red blood cells, while transfusion of stored blood leads to a decrease in 2, 3-DPG levels. Autotransfusion had no effect on hemodynamic parameters, oxygen delivery or oxygen extraction.     

Variability in Transfusion Practice for Coronary Artery Bypass Surgery Persists Despite National Consensus Guidelines: A 24-Institution Study

Background: An estimated 20% of allogeneic blood transfusions in the United States are associated with cardiac surgery. National consensus guidelines for allogeneic transfusion associated with coronary artery bypass graft (CABG) surgery have existed since the mid- to late 1980s. The appropriateness and uniformity of institutional transfusion practice was questioned in 1991. An assessment of current transfusion practice patterns was warranted.

Methods: The Multicenter Study of Perioperative Ischemia database consists of comprehensive information on the course of surgery in 2,417 randomly selected patients undergoing CABG surgery at 24 institutions. A subset of 713 patients expected to be at low risk for transfusion was examined. Allogeneic transfusion was evaluated across institutions. Institution as an independent risk factor for allogeneic transfusion was determined in a multivariable model.

Results: Significant variability in institutional transfusion practice was observed for allogeneic packed red blood cells (PRBCs) (27-92% of patients transfused) and hemostatic blood components (platelets, 0-36%; fresh frozen plasma, 0-36%; cryoprecipitate, 0-17% of patients transfused). For patients at institutions with liberal rather than conservative transfusion practice, the odds ratio for transfusion of PRBCs was 6.5 (95% confidence interval [CI], 3.8-10.8) and for hemostatic blood components it was 2 (95% CI, 1.2-3.4). Institution was an independent determinant of transfusion risk associated with CABG surgery.     

The decrease of preoperative autologous transfusion in France has not been linked to an increase of homologous red cell concentrates

Objective

The use of preoperative autologous blood transfusion has dramatically decreased in France. The aim of this study was to evaluate the evolution of practice both of autologous and homologous Red Blood Cells (RBC) concentrates transfusion between 2002 and 2005, and to asses the consequences of the highlighted changes.

Material and methods

Data on blood transfusion are collected and validated nationwide by a network of regional coordinators of haemovigilance. For each hospital, from 2002 to 2005, the annual changes in the number of transfused homologous and autologous RBC have been evaluated. The ratio of preoperative autologous RBC, number of autologous RBC divided by the number of all RBC, has also been calculated. Hospitals have been split into three cohorts, according to their 2005 autologous RBC ratio. For each cohort, correlations between the variations of the number of autologous, homologous and total RBC in each hospital have been studied.

Results

Data have been validated for 22 French regions that performed 71.8% of the total French transfusion in 2004. In 2005, 1,831,544 labile blood products have been transfused in 1197 hospitals and clinics among which 379 have used preoperative autologous transfusion. A total of 37,289 autologous RBC have been transfused in 2003, 28,689 in 2004 (−23.1%) and 17,758 in 2005 (−38.1%). The first cohort of 269 hospitals had a ratio of autologous RBC under 3%, the second cohort of 38 hospitals, a ratio between 3 and 6%, while the third cohort of 72 hospitals had transfused 6% or more of autologous RBC. In the two first cohorts, non-surgical activities were so large that it was impossible to assess the changes in surgical use of transfusion. The third cohort, with a ratio of 6% or more, was essentially devoted to surgery (88% of beds). These hospitals and clinics have transfused 13,076 autologous RBC in 2002 and 8583 in 2005 (−34.4%). In this group, there was a statistical correlation between the decrease of autologous RBC and the decrease of total RBC (r² = 0.36), and no increase in the transfusion of homologous RBC has been observed. During the same period, neither hospitals nor clinics showed any decrease of their surgical activity. The drop of autologous RBC transfusion led to a decrease of the total number of RBC transfused and thus, to a decrease of the global exposure to transfusion hazard.

Conclusion

The present results confirmed a decline of preoperative autologous transfusion in France, between 2002 and 2005. Meanwhile no supplementary need of homologous RBC has been observed among hospitals, performing surgery that formerly had a high ratio of autologous RBC.     

An audit of transfusion of red blood cell units in pediatric anesthesia

Background:  Patients undergoing surgery are an important user of red blood cells (RBC). Increasingly, medical staff and patients wish to know the likelihood of RBC transfusion for appropriate resource allocation and to inform preoperative discussions regarding risk. Although some adult data are available, little is known about RBC use in children.
Aim:  The aim of this study was to describe RBC use in the perioperative period in a large pediatric hospital.
Methods:  Over a 2-year period the hospital operating theatre database and trauma registry was merged with the blood bank database to identify episodes where RBC units were transfused in association with anesthesia. Incidence of transfusion of RBC units associated with particular procedures was then calculated.
Results:  A total of 21 441 patients underwent 32 511 anesthetics from January 1, 2006 to December 31, 2007, and 9838 units of RBC were released from the hospital blood bank of which 4070 (41%) were transfused in the perioperative period. Cardiac surgery was the greatest user of RBC units (2359 units). Acute major trauma accounted for only 159 units. Overall 6.3% of anesthetics were associated with a RBC transfusion. The procedures with the greatest frequency of RBC transfusion were cardiac surgery on bypass (79%), cardiac off bypass (55%), liver transplant (87%) and cranioplasty (61%).
Conclusion:  In a tertiary pediatric hospital surgery accounts for a substantial proportion of total RBC use, with particular procedures accounting for the majority of transfusions.