A predictive model for blood transfusion during liver resection
European journal of surgical oncology : the journal of the European Society of Surgical Oncology and the British Association of Surgical Oncology. 2022
BACKGROUND A predictive model that can identify patients who are at increased risk of intraoperative blood transfusion could guide preoperative transfusion risk counseling, optimize health care resources, and reduce medical costs. Although previous studies have identified some predictors for particular populations, there is currently no existing model that uses preoperative variables to accurately predict blood transfusion during surgery, which could help anesthesiologists optimize intraoperative anesthetic management. METHODS We collected data from 582 patients who underwent elective liver resection at a university-affiliated tertiary hospital between January 1, 2018, and December 31, 2020. The data set was then randomly divided into a training set (n = 410) and a validation set (n = 172) at a 7:3 ratio. The least absolute shrinkage and selection operating regression model was used to select the optimal feature, and multivariate logistic regression analysis was applied to construct the transfusion risk model. The concordance index (C-index) and the area under the receiver operating characteristic (ROC) curve (AUC) were used to evaluate the discrimination ability, and the calibration ability was assessed with calibration curves. In addition, we used decision curve analysis (DCA) to estimate the clinical application value. For external validation, the test set data were employed. RESULTS The final model had 8 predictor variables for intraoperative blood transfusion, which included the following: preoperative hemoglobin level, preoperative prothrombin time >14 s, preoperative total bilirubin >21 μmol/L, respiratory diseases, cirrhosis, maximum lesion diameter >5 cm, macrovascular invasion, and previous abdominal surgery. The model showed a C-index of 0.834 (95% confidence interval, 0.789-0.879) for the training set and 0.831 (95% confidence interval, 0.766-0.896) for the validation set. The AUCs were 0.834 and 0.831 for the training and validation sets, respectively. The calibration curve showed that our model had good consistency between the predictions and observations. The DCA demonstrated that the transfusion nomogram was reliable for clinical applications when an intervention was decided at the possible threshold across 1%-99% for the training set. CONCLUSION We developed a predictive model with excellent accuracy and discrimination ability that can help identify those patients at higher odds of intraoperative blood transfusion. This tool may help guide preoperative counseling regarding transfusion risk, optimize health care resources, reduce medical costs, and optimize anesthetic management during surgery.
Efficacy of UVC-treated, pathogen-reduced platelets versus untreated platelets: a randomized controlled non-inferiority trial
Pathogen reduction (PR) technologies for blood components have been established to reduce the residual risk of known and emerging infectious agents. THERAFLEX UVPlatelets, a novel UVC light-based PR technology for platelet concentrates, works without photoactive substances. This randomized, controlled, double-blind, multicenter, noninferiority trial was designed to compare the efficacy and safety of UVC-treated platelets to that of untreated platelets in thrombocytopenic patients with hematologic-oncologic diseases. Primary objective was to determine non-inferiority of UVC-treated platelets, assessed by the 1-hour corrected count increment (CCI) in up to eight per-protocol platelet transfusion episodes. Analysis of the 171 eligible patients showed that the defined non-inferiority margin of 30% of UVC-treated platelets was narrowly missed as the mean differences in 1-hour CCI between standard platelets versus UVC-treated platelets for intention-to-treat and perprotocol analyses were 18.2% (95% confidence interval [CI]: 6.4%; 30.1) and 18.7% (95% CI: 6.3%; 31.1%), respectively. In comparison to the control, the UVC group had a 19.2% lower mean 24-hour CCI and was treated with an about 25% higher number of platelet units, but the average number of days to next platelet transfusion did not differ significantly between both treatment groups. The frequency of low-grade adverse events was slightly higher in the UVC group and the frequencies of refractoriness to platelet transfusion, platelet alloimmunization, severe bleeding events, and red blood cell transfusions were comparable between groups. Our study suggests that transfusion of pathogen-reduced platelets produced with the UVC technology is safe but non-inferiority was not demonstrated. (The German Clinical Trials Register number: DRKS00011156).
Evaluation of a novel Cardiac Peri-Operative Transfusion Trigger Scoring system in patients with coronary artery disease
BMC cardiovascular disorders. 2021;21(1):40
BACKGROUND A simple and accurate scoring system to guide perioperative blood transfusion in patients with coronary artery disease (CAD) undergoing cardiac surgery is lacking. The trigger point for blood transfusions for these patients may be different from existing transfusion guidelines. This study aimed to evaluate the safety and efficacy of a new scoring strategy for use in guiding transfusion decisions in patients with CAD. METHODS A multicenter randomized controlled trial was conducted at three third-level grade-A hospitals from January 2015 to May 2018. Data of 254 patients in a Cardiac Peri-Operative Transfusion Trigger Score (cPOTTS) group and 246 patients in a group receiving conventional evaluation of the need for transfusion (conventional group) were analysed. The requirements for transfusion and the per capita consumption of red blood cells (RBCs) were compared between groups. RESULTS Baseline characteristics of the two groups were comparable. Logistic regression analyses revealed no significant differences between the two groups in primary outcomes (1-year mortality and perioperative ischemic cardiac events), secondary outcomes (shock, infections, and renal impairment), ICU admission, and ICU stay duration. However, patients in the cPOTTS group had significantly shorter hospital stays, lower hospital costs, lower utilization rate and lower per capita consumption of transfused RBCs than controls. Stratified analyses revealed no significant differences between groups in associations between baseline characteristics and perioperative ischemic cardiac events, except for hemofiltration or dialysis and NYHA class in I. CONCLUSIONS This novel scoring system offered a practical and straightforward guideline of perioperative blood transfusion in patients with CAD. Trial registration chiCTR1800016561(2017/7/19).
Restrictive Transfusion Strategy after Cardiac Surgery
BACKGROUND Recent guidelines on transfusion in cardiac surgery suggest that hemoglobin might not be the only criterion to trigger transfusion. Central venous oxygen saturation (Svo2), which is related to the balance between tissue oxygen delivery and consumption, may help the decision process of transfusion. We designed a randomized study to test whether central Svo2-guided transfusion could reduce transfusion incidence after cardiac surgery. METHODS This single center, single-blinded, randomized controlled trial was conducted on adult patients after cardiac surgery in the intensive care unit (ICU) of a tertiary university hospital. Patients were screened preoperatively and were assigned randomly to two study groups (control or Svo2) if they developed anemia (hemoglobin less than 9 g/dl), without active bleeding, during their ICU stay. Patients were transfused at each anemia episode during their ICU stay except the Svo2 patients who were transfused only if the pretransfusion central Svo2 was less than or equal to 65%. The primary outcome was the proportion of patients transfused in the ICU. The main secondary endpoints were (1) number of erythrocyte units transfused in the ICU and at study discharge, and (2) the proportion of patients transfused at study discharge. RESULTS Among 484 screened patients, 100 were randomized, with 50 in each group. All control patients were transfused in the ICU with a total of 94 transfused erythrocyte units. In the Svo2 group, 34 (68%) patients were transfused (odds ratio, 0.031 [95% CI, 0 to 0.153]; P < 0.001 vs. controls), with a total of 65 erythrocyte units. At study discharge, eight patients of the Svo2 group remained nontransfused and the cumulative count of erythrocyte units was 96 in the Svo2 group and 126 in the control group. CONCLUSIONS A restrictive transfusion strategy adjusted with central Svo2 may allow a significant reduction in the incidence of transfusion.
Thromboelastometry and a hemostasis management system are most beneficial for guiding hemostatic therapy in cardiac surgery patients with a EuroSCORE II of >/=1.83%: a randomized controlled two-step trial
J Anesth. 2020
PURPOSE We evaluated the efficacy of hemostatic therapy based on point-of-care (POC) testing in patients undergoing cardiac surgery. METHODS This was a single-institution, prospective, randomized, double-blinded study. In step 1, 90 patients scheduled for elective cardiac surgery underwent complete blood count and fibrinogen measurements at baseline, after cardiopulmonary bypass (CPB) initiation (CPB start), just after CPB end, and in the intensive care unit (ICU). In step 2, 72 patients scheduled for elective cardiac surgery underwent conventional laboratory coagulation tests (control group) or POC coagulation tests (POC group). Transfusions were prepared using the fibrinogen and platelet values at mainly "CPB start" for the control group, and using the ROTEM values at mainly "CPB end" for the POC group. Consequently, the step 2 patients were divided into high- and low-risk subgroups based on the EuroSCORE II by logistic regression analysis; transfusion data and bleeding volumes were compared between the control and POC groups within the high- and low-risk subgroups. RESULTS In step 1, all blood components were significantly decreased at CPB start compared with baseline, and platelet and fibrinogen levels remained almost constant from CPB start to end. In step 2, the transfusion rates and perioperative bleeding volumes did not significantly differ between the control and POC groups. Subgroup analysis suggested that only the high-risk subgroup significantly differed regarding perioperative red blood cell transfusion and total bleeding volume in the ICU. CONCLUSIONS POC testing is beneficial for cardiac surgery patients with a EuroSCORE II of ≥1.83%.
FEEding DURing red cell transfusion (FEEDUR RCT): a multi-arm randomised controlled trial
BMC Pediatr. 2020;20(1):346
BACKGROUND Necrotising Enterocolitis (NEC) is a devastating neonatal disease. A temporal association between red cell transfusion and NEC has been recognized and there have been concerns about the effects of feeding during transfusion. We aimed to assess the effect of different enteral feeding regimens on splanchnic oxygenation in preterm infants receiving red cell transfusions. METHODS This was an open, multi-arm, parallel-group, randomised controlled trial conducted in a single centre in Australia. We compared three different enteral feeding regimes during a single red cell transfusion in preterm infants < 35 weeks gestational age at birth. Infants were randomised to either: (1) Withholding enteral feeds for 12 h from the start of transfusion or; (2) Continuing enteral feeds or; (3) Restriction of enteral feed volume to 120 ml/kg/day (maximum 20 kcal/30 ml) for 12 h. The primary outcome was mean splanchnic-cerebral oxygenation ratio (SCOR) and mean splanchnic fractional oxygen extraction (FOE) before (1 h prior), during (1 h into transfusion) and after (end of transfusion; 12 and 24 h post) transfusion. RESULTS There were 60 transfusion episodes (20 transfusion episodes in each group) included in the analysis. 41 infants with a median gestational age at birth of 27 weeks (range 23-32 weeks) were enrolled. The median postnatal age was 43 days (range 19-94 days) and the median pre-transfusion haematocrit was 0.27 (range 0.22-0.32). All three groups were similar at baseline. There were no differences in mean SCOR and mean splanchnic FOE at any of the pre-specified time points. There were also no differences in clinical outcomes. There were no episodes of NEC in any infant. Across all groups the mean SCOR increased from the start to the end of each transfusion (0.97 [CI95% 0.96-0.98] vs 1.00 [CI95% 0.99-1.01]; p = 0.04) and the mean FOE decreased from the start to the end of each transfusion (0.22 [CI95% 0.21-0.23] vs 0.17 [CI95% 0.16-0.18]; p < 0.001). CONCLUSIONS There were no differences in splanchnic oxygenation when enteral feeds were either withheld, continued or restricted during a transfusion. However, the successful conduct of this study supports the feasibility of a large trial powered to assess clinical outcomes. TRIAL REGISTRATION ANZCTR, ACTRN12616000160437. Registered 10 February 2016, https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=370069.
Preterm infants receiving red cell transfusions enrolled in the FEEding DURing red cell transfusion (FEEDUR RCT) trial, (n= 41).
Enteral feeds withheld for 12 hours from the start of transfusion (n= 19).
Enteral feeds continued (n= 18). Enteral feed volume restricted to 120 ml/kg/day for 12 hours (n= 17).
Sixty transfusion episodes (20 transfusion episodes in each group) were included in the analysis. There were no differences in mean splanchnic-cerebral oxygenation ratio (SCOR) and mean splanchnic fractional oxygen extraction (FOE) at any of the pre-specified time points. There were also no differences in clinical outcomes. There were no episodes of necrotising enterocolitis in any infant. Across all groups the mean SCOR increased from the start to the end of each transfusion (0.97 vs 1.00) and the mean FOE decreased from the start to the end of each transfusion (0.22 vs 0.17). There were no differences in splanchnic oxygenation when enteral feeds were either withheld, continued or restricted during a transfusion.
Point-of-care testing: a prospective, randomized clinical trial of efficacy in coagulopathic cardiac surgery patients
INTRODUCTION The current investigation aimed to study the efficacy of hemostatic therapy guided either by conventional coagulation analyses or point-of-care (POC) testing in coagulopathic cardiac surgery patients. METHODS Patients undergoing complex cardiac surgery were assessed for eligibility. Those patients in whom diffuse bleeding was diagnosed after heparin reversal or increased blood loss during the first 24 postoperative hours were enrolled and randomized to the conventional or POC group. Thromboelastometry and whole blood impedance aggregometry have been performed in the POC group. The primary outcome variable was the number of transfused units of packed erythrocytes during the first 24 h after inclusion. Secondary outcome variables included postoperative blood loss, use and costs of hemostatic therapy, and clinical outcome parameters. Sample size analysis revealed a sample size of at least 100 patients per group. RESULTS There were 152 patients who were screened for eligibility and 100 patients were enrolled in the study. After randomization of 50 patients to each group, a planned interim analysis revealed a significant difference in erythrocyte transfusion rate in the conventional compared with the POC group [5 (4;9) versus 3 (2;6) units [median (25 and 75 percentile)], P<0.001]. The study was terminated early. The secondary outcome parameters of fresh frozen plasma and platelet transfusion rates, postoperative mechanical ventilation time, length of intensive care unit stay, composite adverse events rate, costs of hemostatic therapy, and 6-month mortality were lower in the POC group. CONCLUSIONS Hemostatic therapy based on POC testing reduced patient exposure to allogenic blood products and provided significant benefits with respect to clinical outcomes.
A randomized controlled pilot study of adherence to transfusion strategies in cardiac surgery
BACKGROUND It is important to determine the optimal hemoglobin (Hb) concentration for red blood cell (RBC) transfusion for patients undergoing cardiac surgery because increased mortality has been associated with the severity of anemia and exposure to RBCs. Because a definitive trial will require thousands of patients, and because there is variability in transfusion practices, a pilot study was undertaken to determine adherence to proposed strategies. STUDY DESIGN AND METHODS A single-center parallel randomized controlled pilot trial was conducted in high-risk cardiac patients to assess adherence to two transfusion strategies. Fifty patients were randomly assigned either to a "restrictive" transfusion strategy (RBCs if their Hb concentration was 70 g/L or less intraoperatively during cardiopulmonary bypass [CPB] and 75 g/L or less postoperatively) or a "liberal" transfusion strategy (RBCs if their Hb concentration was 95 g/L or less during CPB and less than 100 g/L postoperatively). RESULTS The percentage of adherence overall was 84% in the restrictive arm and 41% in the liberal arm. Twenty-two (88%) patients were transfused 99 units of RBCs in the liberal group compared to 13 patients who were transfused 50 units in the restrictive group (p<0.01). There were no significant differences in individual adverse outcomes; however, more adverse events occurred in the restrictive group (38 vs. 15, p<0.01). CONCLUSION Adherence to the evaluated interventions is vital to all randomized controlled trials as it has the potential to affect outcomes. Further pilot studies are required to optimize enrollment and transfusion adherence before a definitive study is conducted. 2011 American Association of Blood Banks.
Thromboelastometrically guided transfusion protocol during aortic surgery with circulatory arrest: a prospective, randomized trial
The Journal of Thoracic and Cardiovascular Surgery. 2010;140((5):):1117-24.e2.
OBJECTIVE Aortic surgical procedures requiring hypothermic circulatory arrest are associated with altered hemostasis and increased bleeding. In a randomized clinical trial, we evaluated effects of thromboelastometrically guided algorithm on transfusion requirements. METHODS Fifty-six consecutive patients (25 with acute type A dissection) undergoing aortic surgery with hypothermic circulatory arrest were enrolled in a randomized trial during a 6-month period. Patients were randomly allocated to treatment group (n = 27) with thromboelastometrically guided transfusion algorithm or control group (n = 29) with routine transfusion practices (clinical judgment-guided transfusion followed by transfusion according to coagulation test results). Primary end point was cumulative allogeneic blood units (red blood cells, fresh-frozen plasma, and platelets) transfused. RESULTS Transfusion of allogeneic blood was significantly reduced in the thromboelastometry group: median 9. 0 units (interquartile range, 2. 0-30. 0 units) versus. 16. 0 units (9. 0-23. 0 units, P = . 02). Most significant decrease was in the use of fresh-frozen plasma (3. 0 units, 0-12. 0 units, vs 8. 0 units, 4. 0-18. 0 units, P = . 005). Postoperative blood loss (890 mL/d, 600-1250 mL/d vs 950 mL/d, 650-1400 mL/d, p = 0. 5) and rate of surgical re-exploration (19% vs 24%, P = . 7) were similar between groups. Thromboelastometrically guided algorithm significantly decreased need for massive perioperative transfusion (odds ratio, 0. 45; 95% confidence interval, 0. 2-0. 9; P = . 03) in multivariable logistic regression analysis. CONCLUSIONS Thromboelastometrically guided transfusion is associated with a decreased use of allogeneic blood units and reduced incidence of massive transfusion in patients undergoing aortic surgery with circulatory arrest.
Closed system for blood sampling and transfusion in critically ill patients
Revista Brasileira de Terapia Intensiva. 2010;22((1)):5-10.
OBJECTIVE Anemia is common in severely ill patients, and blood sampling plays a relevant causative role. Consequently, blood transfusions are frequent an related to several complications. Trying to reduce the transfusion-related risk, minimizing blood loss is mandatory. Thus, this work aimed to evaluate a closed blood sampling system as a strategy to spare unnecessary blood losses and transfusions. METHODS This was a prospective, randomized, controlled, multicenter, 6 months, clinical trial. The patients were assigned to either VAMP (Venous Arterial Blood Management Protection) group, using a closed blood sampling system, or control group. The groups' transfusion rate, as well as hemoglobin (Hb) and Hematocrit (Ht) changes were compared for 14 days. RESULTS Were included 127 patients, 65 assigned to the control group, and 62 to VAMP. During the intensive care unit stay, both groups experienced both hemoglobin and hematocrit drops. However, when the final Ht and Hb were compared between the groups, a difference was identified with higher values in the VAMP group (p=0.03; p=0.006, respectively). No statistical difference was found for both groups transfusion rates, although the VAMP group had an absolute 12% blood transfusion reduction. CONCLUSION The use of a closed blood sampling system was able to minimize blood count values changes, however failed to reduce transfusions rate.