A comparison of aprotinin and lysine analogues in high-risk cardiac surgery

Enhanced Antifibrinolytic Efficacy of a Plasmin-Specific Kunitz-Inhibitor (60-Residue Y11T/L17R with C-Terminal IEK) of Human Tissue Factor Pathway Inhibitor Type-2 Domain1

Current antifibrinolytic agents reduce blood loss by inhibiting plasmin active sites (e.g., aprotinin) or by preventing plasminogen/tissue plasminogen activator (tPA) binding to fibrin clots (e.g., ε-aminocaproic acid and tranexamic acid); however, they have adverse side effects. Here, we expressed 60-residue (NH2NAE…IEKCOOH) Kunitz domain1 (KD1) mutants of human tissue factor pathway inhibitor type-2 that inhibit plasmin as well as plasminogen activation. A single (KD1-L17R-KCOOH) and a double mutant (KD1-Y11T/L17R- KCOOH) were expressed in Escherichia coli as His-tagged constructs, each with enterokinase cleavage sites. KD1-Y11T/L17R-KCOOH was also expressed in Pichia pastoris. KD1-Y11T/L17R-KCOOH inhibited plasmin comparably to aprotinin and bound to the kringle domains of plasminogen/plasmin and tPA with Kd of ~50 nM and ~35 nM, respectively. Importantly, compared to aprotinin, KD1-L17R-KCOOH and KD1-Y11T/L17R-KCOOH did not inhibit kallikrein. Moreover, the antifibrinolytic potential of KD1-Y11T/L17R-KCOOH was better than that of KD1-L17R-KCOOH and similar to that of aprotinin in plasma clot-lysis assays. In thromboelastography experiments, KD1-Y11T/L17R-KCOOH was shown to inhibit fibrinolysis in a dose dependent manner and was comparable to aprotinin at a higher concentration. Further, KD1-Y11T/L17R-KCOOH did not induce cytotoxicity in primary human endothelial cells or fibroblasts. We conclude that KD1-Y11T/L17R-KCOOH is comparable to aprotinin, the most potent known inhibitor of plasmin and can be produced in large amounts using Pichia.

Analysis of serum tranexamic acid in patients undergoing open heart surgery

BACKGROUND

Tranexamic acid is a drug used during open cardiac surgery to prevent blood loss. The blood levels of 10-100 µg/mL are reported to be in the therapeutic range and higher levels are linked to increased incidence of adverse effects. The aim of this study was to optimize and validate an LC-MS/MS method for serum tranexamic acid and measure its levels in patients from the DEPOSITION Pilot trial in order to prove the concept that topical administration will yield lower serum concentration.

METHODS

The method development was carried out in several steps including sample preparation, and optimization of chromatography and tandem mass spectrometry parameters. Method validation including day-to-day precision with 4 QC levels, limit of detection, sample stability, carryover, and concentration-signal linearity was carried out. Ninety patient samples were analyzed using the validated method.

RESULTS

Fast and efficient LC-MS/MS method for analysis of tranexamic acid in serum was developed. The run time was 7 min with the total time of one hour including the sample preparation. The method precision was acceptable (%CV = 10.5-12.6%) with no sample carryover observed. The matrix effect on the analytical sensitivity was negligible and the lower limit of detection was 0.5 µg/mL. The difference in the mean adjusted concentrations between topical (45 patients) and intravenous (45 patients) groups was statistically significant (0.1154 µg/mL/kg vs. 0.2542 µg/mL/kg, p < 0.0001) CONCLUSIONS: Rapid and simple LC-MS/MS method for analysis of tranexamic acid was optimized and validated. The laboratory has played a crucial role in proving the concept that topical administration yields significantly lower systemic levels of tranexamic acid, and thus decreases the risk of adverse outcomes in patients undergoing open cardiac surgery.

Usefulness of Tranexamic Acid Administration During Sagittal Split Ramus Osteotomy

ABSTRACT

Tranexamic acid has been used to reduce intraoperative bleeding; however, its effect on anti-inflammation and the amount of drainage after orthognathic surgery is yet to be determined. Therefore, we aimed to examine the effect of tranexamic acid on intraoperative bleeding volume and operation time, amount of drainage, and anti-inflammation after orthognathic surgery. Forty healthy women who underwent bilateral sagittal split ramus osteotomy under general anesthesia participated in this study. The amount of intraoperative bleeding, the operation time, the amount of drainage, and the C-reactive protein level were compared between patients intravenously administered with tranexamic acid before surgery (before-surgery group) and those administered with the drug after surgery (after-surgery group). All data were analyzed using the Student t-test. Results were considered to be statistically significant when P < 0.05. Although no significant difference was found in the amount of drainage between the groups (P > 0.05), significant variations were detected in the amount of bleeding during surgery (before-surgery group: 161.7 ± 45.3 mL versus after-surgery group: 270.2 ± 24.0 mL; P = 0.0009), operation time (before-surgery group: 141.3 ± 16.8 min versus after-surgery group: 166.8 ± 24.9 min; P = 0.03), and postoperative C-reactive protein level (before-surgery group: 3.77 ± 0.40 mg/dL versus after-surgery group: 5.02 ± 0.75 mg/dL; P = 0.012) between the groups. In conclusion, administering tranexamic acid before surgery was found to significantly decrease bleeding, reduce operation time, and suppress postoperative inflammation.

Association between intraoperative rotational thromboelastometry or conventional coagulation tests and bleeding in liver transplantation: an observational exploratory study

INTRODUCTION

Liver transplantation is associated with major blood loss and transfusions. Our objective was to evaluate the association between coagulation results (rotational thromboelastometry (ROTEM) and conventional coagulation tests) and intraoperative bleeding or perioperative red blood cell (RBC) transfusions in liver transplantation.

METHODS

We measured ROTEM values and conventional coagulation tests at the beginning of surgery, after graft reperfusion and at the end of surgery. We did bivariate correlation and multivariable regression analyses to explore the association between test results and either intraoperative bleeding or perioperative RBC transfusions.

RESULTS

We enrolled 75 consecutive patients. Median [Q1-Q3] intraoperative blood loss was 1400 mL [675-2300] and 59% of patients did not receive any RBC transfusion either intraoperatively or postoperatively. In multivariable analyses, FIBTEM maximal clot firmness (MCF) measured at the beginning of surgery was associated with lower intraoperative blood loss (ß = -106 mL for each mm; 95% CI, -203 to -9 mL). Both a higher haemoglobin concentration (multiplicative factor = 0.89 for each g/L; 95% CI, 0.84 to 0.95) and FIBTEM MCF measured at the end of surgery (multiplicative factor = 0.68 for each mm; 95% CI, 0.48 to 0.95) were associated with fewer postoperative RBC transfusions.

CONCLUSION

FIBTEM MCF was strongly associated with intraoperative blood loss and postoperative transfusions while other coagulation results were not. This study might inform future clinical trials on ROTEM-based interventions in liver transplantation.

STUDY REGISTRATION

Clinical Trials.gov: NCT02356068.

Comparison of intraoperative tranexamic acid and epsilon-aminocaproic acid in cardiopulmonary bypass patients

Objective

To compare tranexamic acid (TXA) and epsilon-aminocaproic acid (EACA) in patients undergoing cardiac surgery with cardiopulmonary bypass.

Methods

Over a consecutive 2-year period, 824 adult cardiac surgery patients who received TXA during an EACA shortage were compared with 778 patients who received EACA postshortage. Patient characteristics and process and outcome variables were collected through chart review and database queries. This retrospective analysis used inverse probability of treatment weighting to control for confounding by indication, and propensity scores were calculated using a logistic regression model.

Results

In adjusted models, overall transfusion rates for the TXA cohort (odds ratio [OR], 0.94; 95% confidence interval [95% CI], 0.81-1.10) and administration of platelets (OR, 1.04; 95% CI, 0.85-1.27), red blood cells (OR, 0.93; 95% CI, 0.80-1.09), fresh frozen plasma (OR, 1.00; 95% CI, 0.79-1.25), and cryoprecipitate (OR, 1.08; 95% CI, 0.71-1.64) were equivalent to the EACA cohort. In addition, there was no statistical difference with respect to stroke, seizure, mortality, reoperation for bleeding, chest tube drainage, and acute kidney injury. Patients who received TXA had shorter ventilator times (difference in medians -1.33 hours [95% CI, -1.86 to -0.80]) and lower postsurgical charges (difference of medians -$2913 [95% CI, -5147 to -679]).

Conclusions

Substituting TXA for EACA during cardiac surgery with cardiopulmonary bypass did not change transfusion rate or amount, nor was there a significant difference in chest tube drainage. Patients who received TXA had a statistically significant but not clinically significant lower postoperative ventilator times and charges without an increase in mortality, stroke, reoperation for bleeding, acute kidney injury, or seizures.

A randomized, double-blinded trial comparing the effectiveness of tranexamic acid and epsilon-aminocaproic acid in reducing bleeding and transfusion in cardiac surgery

Objectives:

To compare the effectiveness of epsilon aminocaproic acid (EACA) to tranexamic acid (TA) in reducing blood loss and transfusion requirements in patients undergone cardiac surgery under cardiopulmonary bypass.

Design:

Randomized, double blinded study. Outcome variables collected included; baseline demographic characteristics, type of surgery, amount of 24 hour chest tube drainage, amount of 24 hour blood products administered, 30 day mortality and morbidity and length of stay. We analyzed the data using parametric and non-parametric tests as appropriate.

Setting:

Single center tertiary-care university hospital setting.

Participants:

114 patients who had undergone cardiac surgery under cardiopulmonary bypass.

Interventions:

Standard dose of intra-operative EACA or TA was compared in patients undergone cardiac surgery under cardiopulmonary bypass.

Results:

There was no statistically significant difference between groups when analyzing chest tube drainage. However, there was a significant difference in the administration of any transfusion (PRBC's, FFP, platelets) intra-operatively to 24 hours postoperatively, with less transfusion in patients receiving EACA compared to TA (25% vs. 44.8%, respectively P = 0.027). Additionally, there was no significant difference in terms of adverse events during the one month follow up period.

Conclusion:

The findings of this study suggest that EACA and TA have similar effects on chest tube drainage but EACA is associated with fewer transfusions in CABG alone surgeries. Our results suggest that EACA can be used in a similar fashion to TA which may result in a cost and morbidity advantage.

A Pharmacokinetic and Pharmacodynamic Investigation of an ε-Aminocaproic Acid Regimen Designed for Cardiac Surgery With Cardiopulmonary Bypass

OBJECTIVE

To investigate the pharmacokinetics and pharmacodynamics of an ε-aminocaproic acid (EACA) regimen designed for cardiac surgery with cardiopulmonary bypass (CPB).

DESIGN

Prospective observational study requiring blood sampling to measure EACA concentrations and fibrinolysis markers (fibrinogen, D-dimer, α₂-antiplasmin, and tissue plasminogen activator-plasminogen activator inhibitor [tPA-PAI-1] complex).

SETTING

Single-center, tertiary medical center.

PARTICIPANTS

Patients who underwent cardiac surgery with CPB between 2018 and 2019 for aortic or mitral valve replacement/repair or coronary artery bypass grafting. Previous sternotomy patients were included.

INTERVENTION

None.

MEASUREMENTS AND MAIN RESULTS

The pharmacokinetics of EACA, during CPB, were described by a 3-compartment disposition model. EACA concentrations were greater than 130 mg/L in all patients after CPB and in most patients during CPB. The D-dimer level trended up and reached a peak median level of 1.35 mg/L of fibrinogen equivalence units (FEU) at 15 minutes after protamine administration. The median change in D-dimer (ΔD-dimer) from baseline to 15 minutes after protamine was 0.34 (-0.48 to 3.81) mg/L FEU. ΔD-dimer did not correlate with EACA concentration intraoperatively, urine output, body weight, glomerular filtration rate, cell salvage volume, and ultrafiltration volume. The median 24-hour chest tube output was 445 (180-1,011) mL.

CONCLUSION

This regimen provided maximum EACA concentrations near the time of protamine administration, with a total perioperative dose of 15 g. Most patients had EACA concentrations greater than the target during CPB. ΔD-dimer did not correlate with EACA concentration. The median 24-hour chest tube output compared well to similar studies that used higher doses of EACA.

Inhibition of metalloproteinases in therapy for severe lung injury due to COVID-19

Since its first appearance in December 2019 in the Chinese province of Wuhan, COVID-19 has spread rapidly throughout the world and poses a serious threat to public health. Acute respiratory failure due to widespread lung inflammation progress to acute respiratory distress syndrome (ARDS) with an altered pulmonary and alveolar function that can lead to disability, prolong hospitalizations, and adverse outcomes.

While there is no specific treatment for severe acute lung injury (ALI) and ARDS due to the COVID-19 and the management is mostly supportive, it is very important to better understand the pathophysiological processes activated by the inflammatory mediators such as cytokines and metalloproteinases with the aim of their subsequent inhibition in the course of the complex treatment.

Herein, we will discuss the pathophysiological mechanisms of ALI/ARDS, with a focus on the pivotal role played by matrix metalloproteinases (MMP) and the kinin-kallikrein system (KKS), and the effects of the possible pharmacological interventions.

Aprotinin is a nonspecific protease inhibitor especially of trypsin, chymotrypsin, plasmin, and kallikrein, and it is many years in clinical use. Aprotinin inhibits the release of pro-inflammatory cytokines and involved in the process of glycoprotein homeostasis. Experimental data support that the use of aprotinin to inhibit MMPs and KKS may be a new potential approach to the treatment of ALI / ARDS.

Tranexamic acid is an active site inhibitor of urokinase plasminogen activator

TXA is an active-site inhibitor of uPA. TXA attenuates MDA-MB-231 BAG cell migration and inhibits endogenous uPA activity.

Outcome impact of different tranexamic acid regimens in cardiac surgery with cardiopulmonary bypass (OPTIMAL): Rationale, design, and study protocol of a multicenter randomized controlled trial

Tranexamic acid (TxA) reduces perioperative blood transfusion in cardiac surgery; however, the optimal dose of TxA remains unknown. METHODS AND RESULTS: This large-scale, double-blind, randomized controlled trial with a 1-year follow-up enrolls patients undergoing elective cardiac surgery with cardiopulmonary bypass. Patients are randomly assigned 1:1 into either the high-dose TxA group (intravenous bolus [30 mg/kg] after anesthesia followed by intravenous maintenance [16 mg/kg/h] throughout the operation, and a pump prime dose of 2 mg/kg) or the low-dose TxA group (intravenous bolus and maintenance are 10 mg/kg and 2 mg/kg/h, respectively, and a pump prime dose of 1 mg/kg). The primary efficacy end point is the rate of perioperative allogeneic red blood cell (RBC) transfusion defined as the number (%) of patients who will receive at least 1 RBC unit from operation day to discharge. The primary safety end point is the 30-day rate of the composite of perioperative seizures, renal dysfunction, myocardial infarction, ischemic stroke, deep vein thrombosis, pulmonary embolism, and all-cause mortality. The secondary end points are perioperative allogeneic RBC transfusion volume, the non-RBC blood transfusion rate, postoperative bleeding, reoperation rate, mechanical ventilation duration, intensive care unit stay, hospital length of stay, total hospitalization cost, each component of composite primary safety end point, and the 6-month/1-year follow-up mortality and morbidity. We estimated a sample size of 3,008 participants. CONCLUSIONS: The study is designed to identify a TxA dose with maximal efficacy and minimal complications. We hypothesize that the high dose has superior efficacy and noninferior safety to the low dose.

Antifibrinolytics and cardiac surgery: The past, the present, and the future

Cardiac surgery is usually associated with significant blood loss, which often necessitates blood transfusion. In order to decrease the risks associated with the latter, pharmacological as well as nonpharmacological strategies have been used to reduce blood loss. Among the pharmacological approaches, antifibrinolytic drugs are the mainstay. Aprotinin, which was the first ubiquitously used drug, fell into disrepute only to re-emerge after much debate. The decline of aprotinin paved the way for the lysine analogs. However, we must be aware with the side effects of these drugs as well as the dose modification required in special situations. Nonsaccharide glycosaminoglycans have been under investigation to overcome the drawbacks of the lysine analogs. It remains to be seen whether these drugs can replace the traditional antifibrinolytics.

Ulinastatin reduces postoperative bleeding and red blood cell transfusion in patients undergoing cardiac surgery: A PRISMA-compliant systematic review and meta-analysis

BACKGROUND

Ulinastatin is a type of glycoprotein and a nonspecific wide-spectrum protease inhibitor like antifibrinolytic agent aprotinin. Whether Ulinastatin has similar beneficial effects on blood conservation in cardiac surgical patients as aprotinin remains undetermined. Therefore, a systematic review and meta-analysis were performed to evaluate the effects of Ulinastatin on perioperative bleeding and transfusion in patients who underwent cardiac surgery.

METHODS

Electronic databases were searched to identify all clinical trials comparing Ulinastatin with placebo/blank on postoperative bleeding and transfusion in patients undergoing cardiac surgery. Primary outcomes included perioperative blood loss, blood transfusion, postoperative re-exploration for bleeding. Secondary outcomes include perioperative hemoglobin level, platelet counts and functions, coagulation tests, inflammatory cytokines level, and so on. For continuous variables, treatment effects were calculated as weighted mean difference (WMD) and 95% confidential interval (CI). For dichotomous data, treatment effects were calculated as odds ratio and 95% CI. Statistical significance was defined as P < .05.

RESULTS

Our search yielded 21 studies including 1310 patients, and 617 patients were allocated into Ulinastatin group and 693 into Control (placebo/blank) group. There was no significant difference in intraoperative bleeding volume, postoperative re-exploration for bleeding incidence, intraoperative red blood cell transfusion units, postoperative fresh frozen plasma transfusion volumes and platelet concentrates transfusion units between the 2 groups (all P > .05). Ulinastatin reduces postoperative bleeding (WMD = -0.73, 95% CI: -1.17 to -0.28, P = .001) and red blood cell (RBC) transfusion (WMD = -0.70, 95% CI: -1.26 to -0.14, P = .01), inhibits hyperfibrinolysis as manifested by lower level of postoperative D-dimer (WMD = -0.87, 95% CI: -1.34 to -0.39, P = .0003).

CONCLUSION

This meta-analysis has found some evidence showing that Ulinastatin reduces postoperative bleeding and RBC transfusion in patients undergoing cardiac surgery. However, these findings should be interpreted rigorously. Further well-conducted trials are required to assess the blood-saving effects and mechanisms of Ulinastatin.

Comparison of effectiveness of tranexamic acid and epsilon-amino-caproic-acid in decreasing postoperative bleeding in off-pump CABG surgeries: A prospective, randomized, double-blind study

Context

Off-pump coronary artery bypass graft (CABG) surgeries have been shown to have increased fibrinolysis due to tissue plasminogen activator release. There are no trials comparing the two available antifibrinolytics (tranexemic acid and epsilon-amino-caproic acid) in off-pump CABG surgeries.

Aims

The aim of the present study was to compare the effectiveness of tranexamic acid and epsilon-amino-caproic acid with respect to postoperative bleeding at 4 and 24 hours as the primary outcome, and rate of postoperative transfusion, re-operations, complication rate, serum fibrinogen, and D-dimer levels as secondary outcomes.

Settings and Design

The study was carried out at a tertiary-level hospital between June 2017 and June 2018. It was a prospective, randomized, double-blind study.

Materials and Methods

Eighty patients undergoing off-pump CABG, were randomly allocated to receive tranexamic acid or epsilon-amino-caproic acid. The patients were followed up in the postoperative period and were assessed for primary and secondary outcomes.

Statistical Analysis Used

Statistical analysis was performed using SPSS software, version 19.0 (SPSS Inc., Chicago, IL). Nonparametric data were expressed as median with interquartile range and compared using Mann-Whitney U-test, parametric data was represented as mean with standard deviation and analyzed using Student's t-test. Nominal data were analyzed using Chi-square test.

Results

Bleeding at 4 hours did not show significant difference between groups, 180 ml (80-250) vs 200 ml (100-310). Bleeding at 24 hours was significantly lesser in tranexamic acid group as compared to epsilon-amino-caproic acid group, 350 ml (130-520) vs 430 ml (160-730) (P = 0.0022) The rate of transfusion, re-operations, seizures, renal dysfunction, fibrinogen levels, and D-dimer levels did not show significant difference between the groups.

Conclusions

Tranexamic acid significantly reduced postoperative bleeding in off-pump CABG at 24 hours as compared to epsilon-amino-caproic-acid.

Strategies to minimize intraoperative blood loss during major surgery

Background

Reducing operative blood loss improves patient outcomes and reduces healthcare costs. The aim of this article was to review current surgical, anaesthetic and haemostatic intraoperative blood conservation strategies.

Methods

This narrative review was based on a literature search of relevant databases up to 31 July 2019 for publications relevant to reducing blood loss in the surgical patient.

Results

Interventions can begin early in the preoperative phase through identification of patients at high risk of bleeding. Directly acting anticoagulants can be stopped 48 h before most surgery in the presence of normal renal function. Aspirin can be continued for most procedures. Intraoperative cell salvage is recommended when anticipated blood loss is greater than 500 ml and this can be continued after surgery in certain situations. Tranexamic acid is safe, cheap and effective, and routine administration is recommended when anticipated blood loss is high. However, the optimal dose, timing and route of administration remain unclear. The use of topical agents, tourniquet and drains remains at the discretion of the surgeon. Anaesthetic techniques include correct patient positioning, avoidance of hypothermia and regional anaesthesia. Permissive hypotension may be beneficial in selected patients. Promising haemostatic strategies include use of pharmacological agents such as desmopressin, prothrombin complex concentrate and fibrinogen concentrate, and use of viscoelastic haemostatic assays.

Conclusion

Reducing perioperative blood loss requires a multimodal and multidisciplinary approach. Although high-quality evidence exists in certain areas, the overall evidence base for reducing intraoperative blood loss remains limited.

Transfusion strategies in patients with cirrhosis

Bleeding related to portal hypertension and coagulopathy is a common complication in patients with cirrhosis. Complications and management of bleeding is a significant source of healthcare cost and utilization, as well as morbidity and mortality. Due to the scarcity of evidence surrounding transfusion strategies and hemostatic interventions in patients with cirrhosis, there has been significant debate regarding the best practice. Emerging data suggest that evidence supporting transfusion of packed red blood cells to a hemoglobin threshold of 7-8 g/dL is strong. thrombopoietin (TPO) receptor agonists have shown promise in increasing platelet levels and reducing transfusions preprocedurally, although have not specifically been found to reduce bleeding risk. Data for viscoelastic testing (VET)-guided transfusions appear favorable for reducing blood transfusion requirements prior to minor procedures and during orthotopic liver transplantation. Hemostatic agents such as recombinant factor VIIa, prothrombin complex concentrates, and tranexamic acid have been examined but their role in cirrhotic patients is unclear. Other areas of growing interest include balanced ratio and whole blood transfusion. In the following manuscript, we summarize the most up to date evidence for threshold-guided, VET-guided, balanced-ratio, and whole blood transfusions as well as the use of hemostatic agents in cirrhotic patients to provide practice guidance to clinicians.

Fibrinolysis Inhibitors: Potential Drugs for the Treatment and Prevention of Bleeding

Hyperfibrinolytic situations can lead to life-threatening bleeding, especially during cardiac surgery. The approved antifibrinolytic agents such as tranexamic acid, ε-aminocaproic acid, 4-aminomethylbenzoic acid, and aprotinin were developed in the 1960s without the structural insight of their respective targets. Crystal structures of the main antifibrinolytic targets, the lysine binding sites on plasminogen's kringle domains, and plasmin's serine protease domain greatly contributed to the structure-based drug design of novel inhibitor classes. Two series of ligands targeting the lysine binding sites have been recently described, which are more potent than the most-widely used antifibrinolytic agent, tranexamic acid. Furthermore, four types of promising active site inhibitors of plasmin have been developed: tranexamic acid conjugates targeting the S1 pocket and primed sites, substrate-analogue linear homopiperidylalanine-containing 4-amidinobenzylamide derivatives, macrocyclic inhibitors addressing nonprimed binding regions, and bicyclic 14-mer SFTI-1 analogues blocking both, primed and nonprimed binding sites of plasmin. Furthermore, several allosteric plasmin inhibitors based on heparin mimetics have been developed.

Society of Cardiovascular Anesthesiologists Clinical Practice Improvement Advisory for Management of Perioperative Bleeding and Hemostasis in Cardiac Surgery Patients

Bleeding after cardiac surgery is a common and serious complication leading to transfusion of multiple blood products and resulting in increased morbidity and mortality. Despite the publication of numerous guidelines and consensus statements for patient blood management in cardiac surgery, research has revealed that adherence to these guidelines is poor, and as a result, a significant variability in patient transfusion practices among practitioners still remains. In addition, although utilization of point-of-care (POC) coagulation monitors and the use of novel therapeutic strategies for perioperative hemostasis, such as the use of coagulation factor concentrates, have increased significantly over the last decade, they are still not widely available in every institution. Therefore, despite continuous efforts, blood transfusion in cardiac surgery has only modestly declined over the last decade, remaining at ≥50% in high-risk patients. Given these limitations, and in response to new regulatory and legislature requirements, the Society of Cardiovascular Anesthesiologists (SCA) has formed the Blood Conservation in Cardiac Surgery Working Group to organize, summarize, and disseminate the available best-practice knowledge in patient blood management in cardiac surgery. The current publication includes the summary statements and algorithms designed by the working group, after collection and review of the existing guidelines, consensus statements, and recommendations for patient blood management practices in cardiac surgery patients. The overall goal is creating a dynamic resource of easily accessible educational material that will help to increase and improve compliance with the existing evidence-based best practices of patient blood management by cardiac surgery care teams.

ABO blood group does not impact incidence or outcomes of surgery for acute type A aortic dissection

Objectives. To evaluate the distribution and impact of ABO blood groups on postoperative outcomes in patients undergoing surgery for acute type A aortic dissection (ATAAD). Design. A total of 1144 surgical ATAAD patients from eight Nordic centres constituting the Nordic consortium for acute type A aortic dissection (NORCAAD) were analysed. Blood group O patients were compared to non-O subjects. The relative frequency of blood groups was assessed with t-distribution, modified for weighted proportions. Multivariable logistic regression was performed to identify independent predictors of 30-day mortality. Cox regression analyses were performed for assessing independent predictors of late mortality. Results. There was no significant difference in the proportions of blood group O between the study populations in the NORCAAD registry and the background population (40.6 (95% CI 37.7-43.4)% vs 39.0 (95% CI 39.0-39.0)%). ABO blood group was not associated with any significant change in risk of 30-day or late mortality, with the exception of blood group A being an independent predictor of late mortality. Prevalence of postoperative complications was similar between the ABO blood groups. Conclusions. In this large cohort of Nordic ATAAD patients, there were no associations between ABO blood group and surgical incidence or outcomes, including postoperative complications and survival.

Serum Concentrations and Pharmacokinetics of Tranexamic Acid after Two Means of Topical Administration in Massive Weight Loss Skin-Reducing Surgery

Supplemental Digital Content is available in the text.

Background:

Topical administration of tranexamic acid to reduce bleeding is receiving increasing attention, as it is inexpensive, simple, and possibly beneficial in most surgery. Concerns regarding potential systemic adverse effects such as thromboembolic events and seizures may prevent general use of tranexamic acid. Although serum concentrations after topical application are assumed to be low, proper pharmacokinetic studies of tranexamic acid after topical application are lacking.

Methods:

The authors have investigated systemic absorption of tranexamic acid after two means of topical administration in patients undergoing abdominoplasty after massive weight loss: a bolus of 200 ml of 5 mg/ml into the wound cavity versus moistening the wound surface with 20 ml of 25 mg/ml. Twelve patients were recruited in each group. Serum concentrations achieved were compared with those after administration of 1 g as an intravenous bolus to arthroplasty patients. Serial blood samples for tranexamic acid analysis were obtained for up to 24 hours.

Results:

After intravenous administration, the peak serum concentration was 66.1 ± 13.0 µg/ml after 6 ± 2 minutes. Peak serum concentration after topical moistening was 5.2 ± 2.6 µg/ml after 80 ± 33 minutes, and in the topical bolus group, it was 4.9 ± 1.8 µg/ml after 359 ± 70 minutes. Topical moistening resulted in homogenous and predictable absorption across the individuals included, whereas topical bolus administration caused variable and unpredictable serum concentrations.

Conclusion:

Topical administration of tranexamic acid in patients undergoing abdominoplasty results in low serum concentrations, which are highly unlikely to cause systemic effects.

Reducing blood loss in pediatric craniosynostosis surgery by use of tranexamic acid

INTRODUCTION

Craniosysnostosis surgical corrections are routine procedures in the pediatric neurosurgical field. However, these procedures result in significant blood loss. Tranexamic acid (TXA) is an antifibrinolytic drug, which has demonstrated a significant reduction in perioperative blood loss in many pediatric surgical procedures such as cardiac surgery and scoliosis surgery. We conducted a systematic review to evaluate protocols of TXA use in pediatric craniosynostosis procedures and its effect on intraoperative blood loss and transfusions.

MATERIAL AND METHODS

A comprehensive literature review of the National Library of Medicine (PubMed) database was performed to identify relevant studies. We included any clinical study reporting on blood loss or blood transfusion for pediatric craniosynostosis surgery with intraoperative use of tranexamic acid, with the following limits: publication date from inception to May 2019; reports in English.

RESULTS

Thirteen studies were eligible for our review. Of the 13 studies, 4 were prospective, randomised, double-blind controlled trials, 9 were retrospective studies, tailored as a "before-after" studies, comparing blood loss and transfusion without/with TXA. TXA significantly decreases the number and volume of packed red blood cell transfusions and the rate of transfusion in children undergoing craniosynostosis surgery. Significantly fewer fresh frozen plasma transfusions were required in the TXA groups in 2 randomised studies. Length of stay in hospital was significantly lower with the use of TXA in three studies. Advantages of TXA administration also include an excellent patient tolerance of side effects, ease of administration and low cost.

CONCLUSION

TXA significantly reduces blood loss and the need for transfusions in children undergoing craniosynostosis surgery. TXA administration should be a routine part of strategy to reduce blood loss and limit transfusions in these procedures.

Aprotinin versus tranexamic acid in children undergoing cardiac surgery: an observational study

OBJECTIVES

The upcoming release of aprotinin in paediatric cardiac surgery prompted a re-evaluation of its use in comparison to tranexamic acid (TXA) focusing on their effect on exposure to blood transfusions as well as severe postoperative morbidity or mortality.

METHODS

This retrospective study was conducted in a tertiary children hospital from 2002 to 2015. Patients receiving aprotinin (Aprotinin group: 2002-2007) were compared with those receiving TXA group (2008-2015) using propensity score analysis. Primary outcome measures were 'exposure to blood products' and 'severe postoperative morbidity or mortality'. High-risk subgroups that included neonates, complex (Risk Adjusted Classification for Congenital Heart Surgery-1 ≥ 3) and redo surgery were also analysed.

RESULTS

The study included 2157 patients, 1136 in the Aprotinin group and 1021 in the TXA group. Exposure to blood products was significantly higher in the Aprotinin group (78% vs 60%; P < 0.001) as well as in the complex and redo surgery subgroups. Incidence of mortality and/or severe morbidity was higher in the Aprotinin group (33% vs 28%; P = 0.007), as well as in the neonate group. However, cardiopulmonary bypass priming volume and intraoperative fluid balance were significantly decreased, and the use of modified ultrafiltration significantly increased in the TXA group.

CONCLUSIONS

In our population, children receiving aprotinin were more frequently transfused and were at a higher risk of developing severe postoperative morbidity or mortality than those receiving TXA. Subgroups at high risk of bleeding or inflammation did not seem to benefit from aprotinin. These differences might be explained by a safer profile of TXA, but also attributed to major changes in our patient blood management strategies over years.

Review of abdominal solid organ transplantation in Jehovah’s Witness patients

Managing blood loss in Jehovah’s Witness (JW) patients is a matter of controversy. These patients will not accept transfusions of red blood cells, white blood cells, platelets or plasma, even if that is required to save their lives. There are many discussions regarding safety of operating upon JW patients in general surgical procedures, but in solid organ transplantation there is a paucity of literature on this subject. We have reviewed individual case reports and small series documenting on experience with solid organ transplantation in JW patients and the strategies adopted to facilitate that. It is clear that such patients require the surgical team to dedicate more time to ensure their safe management. This begins with a thorough, detailed consent of exactly which products and interventions they will or will not accept. Planning must begin weeks before surgery if possible. Each case must be assessed individually, but provided they meet fitness requirements, there are no absolute contraindications to abdominal organ transplantation.

Living-donor liver transplantation following cardiopulmonary bypass: A case report

RATIONALE

Liver transplantation is an increasingly common treatment for patients with liver cirrhosis or hepatocellular carcinoma. Liver transplantation in patients with heart disease can pose a significant challenge to the transplant teams.

PATIENT CONCERNS

A 46-year-old woman was diagnosed with hepatitis B virus-related hepatocellular carcinoma 3 years ago and had received 3 times transarterial chemoembolization.

DIAGNOSES

The patient was diagnosed as end-stage liver disease due to hepatocellular carcinoma and was scheduled to undergo living-donor liver transplantation. The preoperative echocardiogram revealed mass in the right atrium and the inferior vena cava.

INTERVENTIONS

The patient underwent mass removal under cardiopulmonary bypass followed by liver transplantation.

OUTCOMES

A month later, she was discharged without any complications.

LESSONS

There have only been a few reported cases of anesthetic liver transplantation after a cardiopulmonary bypass. The successful experience described in this case report suggests that some patients may be eligible to undergo a liver transplantation after a cardiopulmonary bypass.

Termination of bleeding by a specific, anticatalytic antibody against plasmin

BACKGROUND

Excessive, plasmin-mediated fibrinolysis augments bleeding and contributes to death in some patients. Current therapies for fibrinolytic bleeding are limited by modest efficacy, low potency, and off-target effects.

OBJECTIVES

To determine whether an antibody directed against unique loop structures of the plasmin protease domain may have enhanced specificity and potency for blocking plasmin activity, fibrinolysis, and experimental hemorrhage.

METHODS

The binding specificity, affinity, protease cross-reactivity and antifibrinolytic properties of a monoclonal plasmin inhibitor antibody (Pi) were examined and compared with those of epsilon aminocaproic acid (EACA), which is a clinically used fibrinolysis inhibitor.

RESULTS

Pi specifically recognized loop 5 of the protease domain, and did not bind to other serine proteases or nine other non-primate plasminogens. Pi was ~7 logs more potent in neutralizing plasmin cleavage of small-molecule substrates and >3 logs more potent in quenching fibrinolysis than EACA. Pi was similarly effective in blocking catalysis of a small-molecule substrate as α2 -antiplasmin, which is the most potent covalent inhibitor of plasmin, and was a more potent fibrinolysis inhibitor. Fab or chimerized Fab fragments of Pi were equivalently effective. In vivo, in a humanized model of fibrinolytic surgical bleeding, Pi significantly reduced bleeding to a greater extent than a clinical dose of EACA.

CONCLUSIONS

A mAb directed against unique loop sequences in the protease domain is a highly specific, potent, competitive plasmin inhibitor that significantly reduces experimental surgical bleeding in vivo.

Blood management in fast-track orthopedic surgery: an evidence-based narrative review

BACKGROUND AND PURPOSE

Innovations able to maintain patient safety while reducing the amount of transfusion add value to orthopedic procedures. Opportunities for improvement arise especially in elective procedures, as long as room for planning is available. Although many strategies have been proposed, there is no consensus about the most successful combination. The purpose of this investigation is to identify information to support blood management strategies in fast-track total joint arthroplasty (TJA) pathway, to (i) support clinical decision making according to current evidence and best practices, and (ii) identify critical issues which need further research.

METHODS AND MATERIALS

We identified conventional blood management strategies in elective orthopedic procedures. We performed an electronic search about blood management strategies in fast-track TJA. We designed tables to match every step of the former with the latter. We submitted the findings to clinicians who operate using fast-track surgery protocols in TJA at our research hospital.

RESULTS

Preoperative anemia detection and treatment, blood anticoagulants/aggregants consumption, transfusion trigger, anesthetic technique, local infiltration analgesia, drainage clamping and removals, and postoperative multimodal thromboprophylaxis are the factors which can add best value to a fast-track pathway, since they provide significant room for planning and prediction.

CONCLUSION

The difference between conventional and fast-track pathways does not lie in the contents of blood management, which are related to surgeons/surgeries, materials used and patients, but in the way these contents are integrated into each other, since elective orthopedic procedures offer significant room for planning. Further studies are needed to identify optimal regimens.

Tranexamic acid reduces heme cytotoxicity via the TLR4/TNF axis and ameliorates functional recovery after spinal cord injury

BACKGROUND

Spinal cord injury (SCI) is a catastrophic trauma accompanied by intralesional bleeding and neuroinflammation. Recently, there is increasing interest in tranexamic acid (TXA), an anti-fibrinolytic drug, which can reduce the bleeding volume after physical trauma. However, the efficacy of TXA on the pathology of SCI remains unknown.

METHODS

After producing a contusion SCI at the thoracic level of mice, TXA was intraperitoneally administered and the bleeding volume in the lesion area was quantified. Tissue damage was evaluated by immunohistochemical and gene expression analyses. Since heme is one of the degraded products of red blood cells (RBCs) and damage-associated molecular pattern molecules (DAMPs), we examined the influence of heme on the pathology of SCI. Functional recovery was assessed using the open field motor score, a foot print analysis, a grid walk test, and a novel kinematic analysis system. Statistical analyses were performed using Wilcoxon's rank-sum test, Dunnett's test, and an ANOVA with the Tukey-Kramer post-hoc test.

RESULTS

After SCI, the intralesional bleeding volume was correlated with the heme content and the demyelinated area at the lesion site, which were significantly reduced by the administration of TXA. In the injured spinal cord, toll-like receptor 4 (TLR4), which is a DAMP receptor, was predominantly expressed in microglial cells. Heme stimulation increased TLR4 and tumor necrosis factor (TNF) expression levels in primary microglial cells in a dose-dependent manner. Similarly to the in vitro experiments, the injection of non-lysed RBCs had little pathological influence on the spinal cord, whereas the injection of lysed RBCs or heme solution significantly upregulated the TLR4 and TNF expression in microglial cells. In TXA-treated SCI mice, the decreased expressions of TLR4 and TNF were observed at the lesion sites, accompanied by a significant reduction in the number of apoptotic cells and better functional recovery in comparison to saline-treated control mice.

CONCLUSION

The administration of TXA ameliorated the intralesional cytotoxicity both by reducing the intralesional bleeding volume and preventing heme induction of the TLR4/TNF axis in the SCI lesion. Our findings suggest that TXA treatment may be a therapeutic option for acute-phase SCI.

Safety and efficacy of intraoperative administration of intravenous tranexamic acid in transurethral resection of prostate: A double-blind, randomised, placebo-controlled trial

Purpose:

The purpose of this article is to evaluate and compare the effect of intravenous tranexamic acid (TXA) with placebo on haemorrhage and quality of vision during and post-transurethral resection of the prostate (TURP).

Methods:

For nine months (September 2016 until June 2017), a randomised clinical trial was conducted with 70 patients, age 50–80 years, who were included in the study according to inclusion criteria (patients who required surgical intervention because of benign prostatic hyperplasia, prostate weight (<100 cc), American Society of Anesthesiologists score ⩽II, etc.) and enrolled randomly one to one in two study groups, and who underwent TURP in Shahid Beheshti Hospital of Hamadan University of Medical Sciences by a single surgeon.

Interventions:

The study group participants received 500 mg TXA in 500 ml ringer serum (concentration of 1 mg/ml, infusion rate 100 mg/min, maximum dose of 15 mg/kg), whereas the control group received only ringer serum during surgery. The results were then compared for the variables operation time, amount of haematocrit (HCT)-haemoglobin (Hb) reduction following surgery and surgeon satisfaction.

Results:

Both groups had no difference in age, weight and prostate weight. Surgeon satisfaction was evaluated at the end of the operation. The frequency of high satisfaction in case and control groups was 74.3% and 8.65%, whereas low satisfaction was 0% and 42.69%, respectively ( p < 0.05). The mean time of operation was 53.57±16.43 vs 120.71±47.76 minutes in the case and control group, respectively ( p < 0.05). The mean HCT-Hb decrease ( p = 0.00) and the amount of infused volume before and after the operation ( p = 0.03) between both groups were significantly different. None of the patients experienced TXA side effects.

Conclusions:

Intravenous TXA can prevent haemorrhage and higher Hb and HCT reduction following TURP, shortening the operation time and improving surgeon vision during TURP.

Level of evidence:

1b

Blood loss and perioperative transfusions related to surgery for spinal tumors. Relevance of tranexamic acid

INTRODUCTION

Tranexamic acid (TXA) has been shown to reduce bleeding. Patients with spinal tumors are fragile and acute anemia may be harmful. Tumor excision surgery is reputed to be hemorrhagic and treatment may increase thromboembolic complications. The aim of this study was to compare blood loss with or without perioperative TXA injection. The transfusion-related and postoperative complications were documents.

METHOD

This retrospective analysis of prospectively collected data involved 83 patients with spinal tumors who underwent decompressive surgery associated with bone fixation. Tranexamic acid was used arbitrarily in 36 of them, while the other 47 did not receive TXA. The overall, intraoperative and postoperative blood loss was recorded. Blood loss was reported relative to the number of fixed levels and the number of levels decompressed by laminectomy. Transfusions were quantified in number of red blood cell packets and erythrocyte volume. Postoperative complications were documented.

RESULTS

Epidemiological and morphological data were similar between groups. There were no significant differences between the two groups in the overall, intraoperative, and postoperative blood loss. A significant reduction in postoperative bleeding was found in the TXA group when the volume was related to the number of decompressed levels. A significant reduction (P<0.05) in the volume of transfused blood was identified in the treated group. No predictor of blood loss was identified, and no additional complications occurred.

CONCLUSION

The efficacy of TXA appears to be moderate during spinal tumor surgery since it does not lead to a reduction in perioperative bleeding. However, a significant reduction in transfusion volume was found without an increase in complications.

Use of Viscoelastography in Malignancy-Associated Coagulopathy and Thrombosis: A Review

The relationship between malignancy and coagulopathy is one that is well documented yet incompletely understood. Clinicians have attempted to quantify the hypercoagulable state produced in various malignancies using common coagulation tests such as prothrombin time, activated partial thromboplastin time, and platelet count; however, due to these tests' focus on individual aspects of coagulation during one specific time point, they have failed to provide clinicians the complete picture of malignancy-associated coagulopathy (MAC). Viscoelastic tests (VETs), such as thromboelastography (TEG) and rotational thromboelastometry (ROTEM), are whole blood analyses that have the advantage of providing information related to the cumulative effects of plasma clotting factors, platelets, leukocytes, and red cells during all stages of the coagulation and fibrinolytic processes. VETs have gained popularity in the care of trauma patients to objectively measure trauma-induced coagulopathy (TIC), but the utility of VETs remains yet unrealized in many other medical specialties. The authors discuss the similarities and differences between TIC and MAC, and propose a mechanism for the hypercoagulable state of MAC that revolves around the thrombomodulin-thrombin complex as it switches between activating the protein C anticoagulation pathway or the thrombin activatable fibrinolysis inhibitor coagulation pathway. Additionally, they review the current literature on the use of TEG and ROTEM in patients with various malignancies. Although limited research is currently available, early results demonstrate the utility of both TEG and ROTEM in the prediction of hypercoagulable states and thromboembolic complications in oncologic patients.

Adjusted calculation model of heparin management during cardiopulmonary bypass in obese patients: A randomised controlled trial

BACKGROUND

Anticoagulation during cardiopulmonary bypass (CPB) is usually adapted to total body weight (TBW). This may be inaccurate in obese patients and lead to heparin overdose with a risk of bleeding.

OBJECTIVES

To validate the efficacy and safety of an adjusted calculation model of heparin dosing based on ideal body weight (IBW) rather than TBW in obese CPB patients, with an expected target mean plasma heparin concentration of 4.5 IU ml after onset of CPB in the experimental group.

DESIGN

Randomised controlled study.

SETTING

University hospital.

PATIENTS

Sixty obese patients (BMI ≥ 30 kg m) scheduled for CPB were included from January to June 2016.

INTERVENTIONS

Patients received a bolus dose of unfractionated heparin of either 300 IU kg of TBW or 340 IU kg of IBW before onset of CPB. Additional adjusted boluses were injected to maintain an activated clotting time (ACT) of at least 400 s.

MAIN OUTCOME MEASURES

Plasma heparin concentration and ACT were measured at different time points. Total heparin doses and transfusion requirements were recorded.

RESULTS

The target heparin concentration of 4.5 IU ml was reached in the IBW group at the onset of CPB and maintained at all time points during CPB. Heparin concentrations were significantly higher in the TBW group after the bolus (6.52 ± 0.97 vs. 4.54 ± 1.13 IU ml, P < 0.001) and after cardioplegia (5.10 ± 1.03 vs. 4.31 ± 1.00 IU ml, P = 0.02). Total heparin doses were significantly higher in the TBW group. Mean ACT was significantly lower in the IBW group but remained over 400 s during CPB. The correlation between heparin and ACT was poor. Peri-operative bleeding and transfusion requirements were comparable. No thrombotic event occurred in the CPB circuit.

CONCLUSION

The current IBW-adjusted regimen of heparin administration may be used efficiently in obese CPB patients, thereby avoiding overdose which cannot be accurately assessed by ACT monitoring alone.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT02675647.

Use of antifibrinolytics in pediatric cardiac surgery: Where are we now?

Fibrinolytic activation is a major and preventable source of bleeding in neonates and children undergoing cardiac surgery with cardiopulmonary bypass. Based on the existing literature (adult and pediatric; cardiac and noncardiac), prophylactic administration of antifibrinolytic agents can help reduce fibrinolytic activation, and consequently reduces perioperative bleeding and the requirement for blood product transfusion. Due to the increased risk of renal failure and mortality reported in adults undergoing cardiac surgery, aprotinin should not be considered as a safe option in neonates and children. Further well-designed studies would be required before the prophylactic administration of aprotinin could be considered in pediatric cardiac surgery. The lysine analogs, tranexamic acid and ϵ-aminocaproic acid,, should be considered as safe and effective antifibrinolytic agents. Although no major side effects have been reported following the administration of lysine analogs in children undergoing cardiac surgery, high-dose tranexamic acid should not be recommended in order to avoid the increased risk of clinical seizures. Despite the recent advances made in our understanding of the pharmacokinetics of tranexamic acid and ϵ-aminocaproic acid,, the optimal plasmatic concentration to be targeted remains unknown. Further studies are therefore urgently needed to better define the optimal dose regimen to be used in neonates and children. In the meantime, the dose regimen published in the most recent pharmacokinetic studies can be used. Although no studies have assessed the effect of massive bleeding and transfusion on the plasmatic concentrations of the lysine analogs, additional boluses might be considered in the presence of bleeding and/or when signs of fibrinolytic activations are observed on viscoelastic hemostatic assays.

The European guideline on management of major bleeding and coagulopathy following trauma: fifth edition

BACKGROUND

Severe traumatic injury continues to present challenges to healthcare systems around the world, and post-traumatic bleeding remains a leading cause of potentially preventable death among injured patients. Now in its fifth edition, this document aims to provide guidance on the management of major bleeding and coagulopathy following traumatic injury and encourages adaptation of the guiding principles described here to individual institutional circumstances and resources.

METHODS

The pan-European, multidisciplinary Task Force for Advanced Bleeding Care in Trauma was founded in 2004, and the current author group included representatives of six relevant European professional societies. The group applied a structured, evidence-based consensus approach to address scientific queries that served as the basis for each recommendation and supporting rationale. Expert opinion and current clinical practice were also considered, particularly in areas in which randomised clinical trials have not or cannot be performed. Existing recommendations were re-examined and revised based on scientific evidence that has emerged since the previous edition and observed shifts in clinical practice. New recommendations were formulated to reflect current clinical concerns and areas in which new research data have been generated.

RESULTS

Advances in our understanding of the pathophysiology of post-traumatic coagulopathy have supported improved management strategies, including evidence that early, individualised goal-directed treatment improves the outcome of severely injured patients. The overall organisation of the current guideline has been designed to reflect the clinical decision-making process along the patient pathway in an approximate temporal sequence. Recommendations are grouped behind the rationale for key decision points, which are patient- or problem-oriented rather than related to specific treatment modalities. While these recommendations provide guidance for the diagnosis and treatment of major bleeding and coagulopathy, emerging evidence supports the author group's belief that the greatest outcome improvement can be achieved through education and the establishment of and adherence to local clinical management algorithms.

CONCLUSIONS

A multidisciplinary approach and adherence to evidence-based guidance are key to improving patient outcomes. If incorporated into local practice, these clinical practice guidelines have the potential to ensure a uniform standard of care across Europe and beyond and better outcomes for the severely bleeding trauma patient.

A Systematic Review and International Web-Based Survey of Randomized Controlled Trials in the Perioperative and Critical Care Setting: Interventions Increasing Mortality

OBJECTIVE

Reducing mortality is a key target in critical care and perioperative medicine. The authors aimed to identify all nonsurgical interventions (drugs, techniques, strategies) shown by randomized trials to increase mortality in these clinical settings.

DESIGN

A systematic review of the literature followed by a consensus-based voting process.

SETTING

A web-based international consensus conference.

PARTICIPANTS

Two hundred fifty-one physicians from 46 countries.

INTERVENTIONS

The authors performed a systematic literature search and identified all randomized controlled trials (RCTs) showing a significant increase in unadjusted landmark mortality among surgical or critically ill patients. The authors reviewed such studies during a meeting by a core group of experts. Studies selected after such review advanced to web-based voting by clinicians in relation to agreement, clinical practice, and willingness to include each intervention in international guidelines.

MEASUREMENTS AND MAIN RESULTS

The authors selected 12 RCTs dealing with 12 interventions increasing mortality: diaspirin-crosslinked hemoglobin (92% of agreement among web voters), overfeeding, nitric oxide synthase inhibitor in septic shock, human growth hormone, thyroxin in acute kidney injury, intravenous salbutamol in acute respiratory distress syndrome, plasma-derived protein C concentrate, aprotinin in high-risk cardiac surgery, cysteine prodrug, hypothermia in meningitis, methylprednisolone in traumatic brain injury, and albumin in traumatic brain injury (72% of agreement). Overall, a high consistency (ranging from 80% to 90%) between agreement and clinical practice was observed.

CONCLUSION

The authors identified 12 clinical interventions showing increased mortality supported by randomized controlled trials with nonconflicting evidence, and wide agreement upon clinicians on a global scale.