Fibrinogen levels following Amicar in surgery for idiopathic scoliosis

Epsilon Aminocaproic Acid’s Safety and Efficacy in Pediatric Surgeries Including Craniosynostosis Repair: A Review of the Literature

Craniosynostosis, the premature fusion of skull sutures in children, requires surgical correction. This procedure routinely requires allogeneic blood transfusions, which are associated with multiple risks of their own. Since 2008, antifibrinolytics tranexamic acid (TXA) and epsilon aminocaproic acid (EACA or Amicar) have been widely used. There is literature comparing the two agents in scoliosis and cardiothoracic surgery, but the literature comparing the two agents in pediatric craniofacial surgery (CF) is limited. Tranexamic acid use is more common in pediatric CF surgery and has been thoroughly studied; however, it costs about three times as much as EACA and has been associated with seizures. This study compiles the literature assessing the safety and efficacy of EACA in reducing blood loss and transfusion volumes in children and explores its potential use in pediatric CF surgery.

Papers from 2000 to 2021 regarding the effectiveness and safety of EACA in Pediatric scoliosis, cardiothoracic, and craniosynostosis surgery were reviewed and compiled. Papers were found via searching PubMed and Cochrane databases with the key terms: Epsilon aminocaproic acid, EACA, Amicar, Tranexamic acid, TXA, craniosynostosis, scoliosis, cardiothoracic, and pediatric. Prospective studies, retrospective studies, and meta-analyses were included.

Twenty-nine papers were identified as pertinent from the literature searched. Four were meta-analyses, 14 were retrospective, and 11 were prospective. Of these papers, seven were of cardiac surgery, 12 were of scoliosis, and nine were of craniosynostosis. During our search, EACA has been shown to consistently reduce blood transfusion volumes compared to control. However, it is not as effective when compared to TXA. EACA has a similar safety profile to TXA but has a reduced risk of seizures. There are not many studies of EACA in craniosynostosis repair, but the existing literature shows promising results for EACA's efficacy and safety, warranting more studies. 

Tranexamic Acid in Pediatric Scoliosis Surgery: A Prospective Randomized Trial Comparing High-dose and Low-dose Tranexamic Acid in Adolescent Idiopathic Scoliosis Undergoing Posterior Spinal Fusion Surgery

STUDY DESIGN

Prospective randomized double-blinded trial.

OBJECTIVE

The objective of this study is to determine the efficacy of high-dose versus low-dose tranexamic acid (TXA) in adolescent idiopathic scoliosis (AIS) corrective surgery.

SUMMARY OF BACKGROUND DATA

Corrective surgery for AIS is associated with significant blood loss. Evidence on the optimum TXA dose to reduce bleeding in pediatric population is scarce.

METHODS

A total of 166 AIS patients aged between 10 and 21 years, of American Society of Anesthesiologists (ASA) physical status I and II, preoperative hemoglobin >10 g/dL, platelet count >150,000 cells/L and Cobb angle of >45° scheduled for elective single-stage posterior spinal fusion (PSF) surgery by two attending surgeons were included between March 2017 and November 2018. Patients were randomized into Group A (High Dose, 30 mg/kg TXA loading dose followed by 10 mg/kg/h infusion) and Group B (Low Dose, 10 mg/kg TXA loading dose followed by 1 mg/kg/h infusion). The primary outcome was total surgical blood loss between both groups. Secondary outcomes were transfusion requirement, perioperative changes in hemoglobin and coagulation profiles, adverse events, and factors that influence total blood loss.

RESULTS

The mean total surgical blood loss between the two groups was not significant (Group A: 928.8 ± 406.1 mL [range: 348-1857 mL]; Group B: 918.1 ± 406.2 mL [range: 271-2000 mL], P = 0.865). The median duration of surgery was 120 minutes. One patient in each group received allogenic blood transfusion during the perioperative period. There were no significant changes in hemoglobin and coagulation profile at pre-operation, post-operation 0 hour and 48 hours. Sex, number of vertebral levels fused, and duration of surgery were independently associated with total surgical blood loss. No adverse events were observed perioperatively.

CONCLUSION

Low-dose TXA was as efficacious as high-dose TXA in reducing blood loss and allogenic blood transfusion for AIS patients undergoing PSF surgery.Level of Evidence: 1.

Aminocaproic Acid for the Reversal of Alteplase: A Case Series

INTRODUCTION

The evidence to support the use of aminocaproic acid for reversal of alteplase is limited to case reports. Current guidelines recommend cryoprecipitate as first-line treatment, or an antifibrinolytic if cryoprecipitate is unavailable or cannot be used. This case series describes the use of aminocaproic acid for alteplase-related hemorrhage.

MATERIALS AND METHODS

Patients who received aminocaproic acid within 48 hours of alteplase from January 1, 2014, to June 30, 2017 were included. Patients were excluded if aminocaproic acid was not administered for an alteplase-related hemorrhage. Thromboembolic complications at 14 days and hemostasis within 24 hours were documented.

RESULTS

Sixteen patients received aminocaproic acid for an alteplase-related hemorrhage. Aminocaproic acid was given for hemorrhagic conversion of acute ischemic stroke in 7 of 16 patients and other types of hemorrhages in the remaining patients. Hemostasis occurred in 3 of 10 evaluable patients. Overall mortality was 63% (10/16). Administration of aminocaproic acid varied significantly (50% bolus, 12.5% infusion, 37.5% bolus plus infusion). One of 6 evaluable patients had a thromboembolic event. All patients received concomitant blood products. Cryoprecipitate was administered in 69% (11/16) of patients.

CONCLUSIONS

There was no clear relationship between the timing or dose of aminocaproic acid and hemostasis, and it is unclear if administration of aminocaproic acid contributes to hemostasis.

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.

Electronic supplementary material

The online version of this article (10.1186/s13054-019-2347-3) contains supplementary material, which is available to authorized users.

Bipolar Sealer Devices Used in Posterior Spinal Fusion for Neuromuscular Scoliosis Reduce Blood Loss and Transfusion Requirements

BACKGROUND

Reducing perioperative blood loss and the need for transfusions in patients undergoing spinal surgery is especially important for those with neuromuscular disorders. These patients require extensive spino-pelvic exposure and are often medically fragile. We have used Amicar to decrease blood loss since 2001. As an effort to further reduce blood loss and transfusions, we use a bipolar sealer device (Aquamantys) as an adjunct to electrocautery. We present the results of our first 64 neuromuscular patients to show the efficacy of the device.

METHODS

Using a prospectively maintained database we reviewed the operative time, estimated perioperative blood loss, cell saver use, and intraoperative and postoperative transfusion rate in patients who underwent posterior spinal fusion for neuromuscular scoliosis. Sixty-four patients were identified who fit these criteria since the use of the bipolar sealer device was instituted.We compared these patients with a control group of the preceding 65 patients in whom this device was not used for hemostasis. All patients, including those in the study group, received Amicar (infusion of 100 mg/kg over 15 to 20 min, then 10 mg/kg/h throughout the remainder of the procedure). The surgical technique did not differ between the 2 groups.

RESULTS

Baseline characteristics between the 2 groups were similar except for the number of patients having an all-screw construct which was larger in the investigational group (25% vs. 8%, P=0.03). There were no significant differences in operative time or duration of hospital stay. Intraoperative blood loss was lower in the study group (741 mL) as compared with the control group (1052 mL, P=0.003). Total perioperative blood loss, however, showed no significant difference. Thirty-five (55%) patients in the study group and 50 (77%) patients in the control group required additional intraoperative or postoperative transfusions (P=0.01). The number of packed red cell units transfused per patient was 0.81 in the study group and 1.57 in the control group (P=0.001). Although the intraoperative cell saver transfusion was same, the total blood volume transfused, which includes cell saver and any other transfusions, was significantly lower in the study group, 425 mL versus 671 mL (P=0.002).

CONCLUSIONS

Use of a bipolar sealer device in posterior spinal fusion for neuromuscular scoliosis significantly reduced intraoperative blood loss and transfusion rate when compared with a control group in this retrospective review.

LEVEL OF EVIDENCE

Level III-retrospective comparative study.

Is Preoperative Fibrinogen Testing Associated With Total Blood Loss in Adolescent Idiopathic Scoliosis Correction?

STUDY DESIGN

Retrospective analysis.

OBJECTIVE

This study sought to investigate the potential association between preoperative fibrinogen, bleeding, and transfusion requirements in adolescent idiopathic scoliosis (AIS) corrections.

SUMMARY OF BACKGROUND DATA

Blood loss after major spinal reconstruction increases the risks and costs of surgery. Preoperative fibrinogen levels may predict intra- and postoperative blood loss.

METHODS

Data were collected from clinic charts and hospital medical records of all 110 of a single surgeon's consecutive AIS patients undergoing greater than three-level deformity correction surgeries from January 2011 to December 2013. Pearson test was used to investigate the correlation between bleeding and clinical variables, with level of significance set at α = 0.05.

RESULTS

Mean total bleeding volume was 488 (±356) mL. Overall, mean preoperative fibrinogen concentration was 188.6 ± 32.8 mg/dL. Preoperative platelet counts, prothrombin time (PT), and activated partial thromboplastin time (aPTT) did not correlate significantly with preoperative fibrinogen concentration (p > .05). Both packed red cells (PRC) and packed red blood cells (PRBC) correlated significantly with preoperative fibrinogen (p < .05). The correlation between PRC and preoperative fibrinogen was -0.042. There was a negative correlation between PRBC and preoperative fibrinogen (r = -0.46). Overall mean thromboelastography (TEG) values were within normal range in both males and females and both had comparable TEG parameter values. All the TEG variables (G, K, and Angle) correlated significantly with preoperative fibrinogen (p < .05) but not with total blood volume (p > .05). The correlation coefficient between these TEG variables and preoperative fibrinogen were 0.51, 0.59, and 0.54, respectively. The total bleeding volume and % estimated blood volume correlated significantly with both PRC (r = 0.352, r = 0.376; p < .05) and PRBC (r = 0.621, r = 0.614; p < .05).

CONCLUSIONS

In our cohort undergoing correction of AIS, preoperative fibrinogen levels exhibited a significant negative logarithmic correlation with total blood loss. TEG variables also correlated significantly with preoperative fibrinogen levels. Efforts should be made to incorporate this measure in perioperative blood management program for AIS corrections.

LEVEL OF EVIDENCE

Level IV.

High Dose, Prolonged Epsilon Aminocaproic Acid Infusion, and Recombinant Factor VII for Massive Postoperative Retroperitoneal Hemorrhage following Splenectomy

The antifibrinolytic agent ε-aminocaproic acid is used to decrease procedural blood loss in a variety of high risk surgeries. The utility of recombinant factor VII administration in massive hemorrhage has also been reported in a variety of settings, though the impact in a surgical context remains unclear. We describe the case of a patient who underwent massive open splenectomy and developed diffuse retroperitoneal bleeding on postoperative day one. Massive transfusion was initiated, but attempts to control hemorrhage with surgical and interventional radiology approaches were unsuccessful, as was recombinant factor VII administration. Commencement of a high dose aminocaproic acid infusion was followed by a prominent rise in fibrinogen levels and stabilization of the hemorrhage. Indications, dosages, and adverse effects of ε-aminocaproic acid as described in the literature are reviewed.

Antifibrinolytic agents for reducing blood loss in scoliosis surgery in children

BACKGROUND

This is an updated version of the original Cochrane review first published in 2008. Scoliosis surgery is often associated with substantial blood loss and potentially detrimental effects in children. Antifibrinolytic agents are often used to reduce perioperative blood loss. Clinical trials have evaluated their efficacy in children undergoing surgical correction of scoliosis, but no systematic review has been published. This review was first published in 2008 and was updated in 2016.

OBJECTIVES

To assess the efficacy and safety of aprotinin, tranexamic acid and aminocaproic acid in reducing blood loss and transfusion requirements in children undergoing surgery for correction of idiopathic or secondary scoliosis.

SEARCH METHODS

We ran the search for the previous review in June 2007. For this updated version, we searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2015, Issue 7), MEDLINE (1946 to August week 1 2015), Embase (1947 to 2015 week 38), Latin American Caribbean Health Sciences Literature (LILACS) (1982 to 14 August 2015), Database of Abstracts of Reviews of Effects (DARE; 2015, Issue 2) and reference lists of reviews and retrieved articles for randomized controlled trials in any language. We also checked the clinical trial registry at http://www.clinicaltrials.gov on 8 October 2015.

SELECTION CRITERIA

We included blinded and unblinded randomized controlled trials (RCTs) that evaluated the effects of antifibrinolytics on perioperative blood loss in children 18 years of age or younger and undergoing scoliosis surgery.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data. The primary outcome was total blood loss (intraoperative and postoperative combined). Secondary efficacy outcomes were the number of participants receiving blood transfusion (both autologous and allogeneic) or receiving allogeneic blood transfusion alone, and the total amount of blood transfused. Safety outcomes included the number of deaths, the number of participants reporting any adverse event or a serious adverse event, withdrawals due to adverse events and the number of participants experiencing a specific adverse event (i.e. renal insufficiency, hypersensitivity or thrombosis). We assessed methodological risk of bias for each included study and employed the GRADE approach to assess the overall quality of the evidence.

MAIN RESULTS

We included three new studies (201 participants) in this updated review, for a total of nine studies (455 participants). All but one study employed placebo as the control group intervention. For the primary outcome, antifibrinolytic drugs decreased the amount of perioperative blood loss by 427 mL (95% confidence interval (CI) 251 to 603 mL), for a reduction of over 20% versus placebo. We rated the quality of evidence for our primary outcome as low on the basis of unclear risk of bias for several domains in most studies and the small total number of participants.For secondary outcomes, fewer participants receiving antifibrinolytic drugs received transfusion (allogeneic or autologous) versus those receiving placebo (risk ratio (RR) 0.65, 95% CI 0.50 to 0.85, number needed to treat to prevent one additional harmful outcome (NNTp) 5; very low-quality evidence). Only two studies specifically evaluated the number of participants transfused with only allogeneic blood (risk difference (RD) -0.15, 95% CI -0.26 to -0.03, NNTp 7; very low-quality evidence). Antifibrinolytic drugs decreased the volume of blood transfused by 327 mL (95% CI -186 to -469 mL; low-quality evidence).No study reported deaths in active or control groups. Data were insufficient to allow performance of meta-analysis for any safety outcome. No studies adequately described their methods in assessing safety. The only adverse event of note occurred in one study, when three participants in the placebo group developed postoperative deep vein thrombosis.

AUTHORS' CONCLUSIONS

Since the last published version of this review (2008), we have found three new studies. Additional evidence shows that antifibrinolytics reduce the requirement for both autologous and allogeneic blood transfusion. Limited evidence of low to very low quality supports the use of antifibrinolytic drugs for reducing blood loss and decreasing the risk, and volume, of transfusion in children undergoing scoliosis surgery. Evidence is insufficient to support the use of a particular agent, although tranexamic acid may be preferred, given its widespread availability. The optimal dose regimen for any of these three agents has not been established. Although adverse events appear to occur infrequently, evidence is insufficient to confirm the safety of these agents, particularly for rare but potentially catastrophic events. No long-term safety data are available.

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

BACKGROUND

Severe trauma continues to represent a global public health issue and mortality and morbidity in trauma patients remains substantial. A number of initiatives have aimed to provide guidance on the management of trauma patients. This document focuses on the management of major bleeding and coagulopathy following trauma and encourages adaptation of the guiding principles to each local situation and implementation within each institution.

METHODS

The pan-European, multidisciplinary Task Force for Advanced Bleeding Care in Trauma was founded in 2004 and included representatives of six relevant European professional societies. The group used 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 reconsidered and revised based on new scientific evidence 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. This guideline represents the fourth edition of a document first published in 2007 and updated in 2010 and 2013.

RESULTS

The guideline now recommends that patients be transferred directly to an appropriate trauma treatment centre and encourages use of a restricted volume replacement strategy during initial resuscitation. Best-practice use of blood products during further resuscitation continues to evolve and should be guided by a goal-directed strategy. The identification and management of patients pre-treated with anticoagulant agents continues to pose a real challenge, despite accumulating experience and awareness. The present guideline should be viewed as an educational aid to improve and standardise the care of the bleeding trauma patients across Europe and beyond. This document may also serve as a basis for local implementation. Furthermore, local quality and safety management systems need to be established to specifically assess key measures of bleeding control and outcome.

CONCLUSIONS

A multidisciplinary approach and adherence to evidence-based guidance are key to improving patient outcomes. The implementation of locally adapted treatment algorithms should strive to achieve measureable improvements in patient outcome.

Use of Tranexamic Acid (TXA) on reducing blood loss during scoliosis surgery in Chinese adolescents

Background

Many reports had been received on the application of antifibrinolytic medications on spinal corrective surgery and the surgical outcome evaluations of its efficacy on reducing blood loss. This study aimed to assess the efficacy of tranexamic acid (TXA) in reducing operative blood loss during posterior spinal fusion for the treatment of severe adolescent idiopathic scoliosis (AIS).

Methods

A retrospective cohort study was carried out on 90 (TXA = 55, Control = 35) AIS girls undergoing posterior spinal surgery. Patients in TXA group used TXA as an antifibrinolytic agent to reduce blood loss, while control group did not. Blood loss, haemoglobin change and amount of blood transfused was estimated from intraoperative measurement by anaesthesiologists. Demographics were compared using Student’s T-test or Chi-square test where appropriate. Linear regression modelling was carried out between the use of TXA and total blood loss with controlling of confounding factors.

Results

Mean age and mean maximum major curve were 15.2 and 73°, and 15.3 and 63° in TXA and control groups respectively. TXA group showed significantly less intra-operative blood loss than the control group from intraoperative measurement (1.8 L vs. 3.9 L, p < 0.01) and volume of cell saver blood transfused back to patients (0.6 L vs. 1.7 L, p < 0.01). TXA group also showed significantly shorter total time taken for surgery (437 min vs. 502 min, p < 0.01), and total blood loss per surgical segment level (0.1 L vs. 0.3 L, p < 0.01). Regression models showed that the use of TXA decreased total blood loss by 794.3 ml after adjusting for maximum major curve, age, number of segments fused, bone graft, clotting capability, and infusion of coagulation factors.

Conclusions

Patients undergoing posterior spinal corrective surgery with the use of TXA showed much reduced total blood loss, reduced use of transfused blood, much less cell saver blood transfused back to the patient. The total blood loss was decreased by after using TXA after controlling for maximum major curve, age, surgical parameters, clotting capability, and infusion of coagulation factors.

Population pharmacokinetics of ϵ-aminocaproic acid in adolescents undergoing posterior spinal fusion surgery

BACKGROUND

Despite demonstrated efficacy of ϵ-aminocaproic acid (EACA) in reducing blood loss in adolescents undergoing spinal fusion, there are no population-specific pharmacokinetic data to guide dosing. The aim of this study was to determine the pharmacokinetics of EACA in adolescents undergoing spinal fusion surgery and make dosing recommendations.

METHODS

Twenty children ages 12-17 years were enrolled, with 10 children in each of two groups based on diagnosis (idiopathic scoliosis or non-idiopathic scoliosis). Previously reported data from infants undergoing craniofacial surgery were included in the model to enable dosing recommendations over a wide range of weights, ages, and diagnoses. A population non-linear mixed effects modelling approach was used to characterize EACA pharmacokinetics.

RESULTS

Population pharmacokinetic parameters were estimated using a two-compartment disposition model with allometrically scaled weight and an age effect on clearance. Pharmacokinetic parameters for the typical patient were a plasma clearance of 153 ml min(-1) 70 kg(-1) (6.32 ml min(-1) kg(-0.75)), intercompartmental clearance of 200 ml min(-1) 70 kg(-1) (8.26 ml min(-1) kg(-0.75)), central volume of distribution of 8.78 litre 70 kg(-1) (0.13 litre kg(-1)), and peripheral volume of distribution of 15.8 litre 70 kg(-1) (0.23 litre kg(-1)). Scoliosis aetiology did not have a clinically significant effect on drug pharmacokinetics.

CONCLUSIONS

The following dosing schemes are recommended according to patient weight: weight <25 kg, 100 mg kg(-1) loading dose and 40 mg kg(-1) h(-1) infusion; weight ≤25 kg-<50 kg, 100 mg kg(-1) loading dose and 35 mg kg(-1) h(-1) infusion; and weight ≥50 kg, 100 mg kg(-1) loading dose and 30 mg kg(-1) h(-1) infusion. An efficacy trial employing this dosing strategy is warranted.

CLINICAL TRIAL REGISTRATION

NCT01408823.

Symptomatic intracerebral hemorrhage in acute ischemic stroke after thrombolysis with intravenous recombinant tissue plasminogen activator: a review of natural history and treatment

IMPORTANCE

Intravenous thrombolysis remains the mainstay treatment for acute ischemic stroke. One of the most feared complications of the treatment is thrombolysis-related symptomatic intracerebral hemorrhage (sICH), which occurs in nearly 6% of patients and carries close to 50% mortality. The treatment options for sICH are based on small case series and expert opinion, and the efficacy of recommended treatments is not well known.

OBJECTIVE

To provide an overview on the rationale and mechanism of action of potential treatments for sICH that may reverse the coagulopathy before hematoma expansion occurs.

EVIDENCE REVIEW

Evidence-based peer-reviewed articles, including randomized trials, case series and reports, and retrospective reviews, were identified in a PubMed search on the mechanism of action of intravenous recombinant tissue plasminogen activator and the rationale of various potential treatments using the coagulation cascade as a model. The search encompassed articles published from January 1, 1990, through February 28, 2014.

FINDINGS

The current treatments may not be sufficient to reverse coagulopathy early enough to prevent hematoma expansion and improve the outcome of thrombolysis-related hemorrhage.

CONCLUSIONS AND RELEVANCE

Given the mechanism of action of intravenous recombinant tissue plasminogen activator, clinical studies could include agents with a fast onset of action, such as prothrombin complex concentrate, recombinant factor VIIa, and ε-aminocaproic acid, as potential therapeutic options.

Fibrinogen Concentrate Does Not Suppress Endogenous Fibrinogen Synthesis in a 24-hour Porcine Trauma Model

Background:

Fibrinogen concentrate may reduce blood loss after trauma. However, its effect on endogenous fibrinogen synthesis is unknown. The authors investigated the effect of exogenous human fibrinogen on endogenous fibrinogen metabolism in a 24-h porcine trauma model.

Methods:

Coagulopathy was induced in 20 German Landrace pigs by hemodilution and blunt liver injury. Animals were randomized to receive fibrinogen concentrate (100 mg/kg; infusion beginning 20 min postinjury and lasting approximately 10 min) or saline. Fibrinogen concentration, thromboelastometry, and quantitative reverse transcriptase polymerase chain reaction of fibrinogen genes in liver tissue samples were recorded. Internal organs were examined histologically for emboli.

Results:

Coagulation parameters were impaired and plasma fibrinogen concentrations were reduced before starting infusion of fibrinogen concentrate/saline. Twenty minutes after starting infusion, exogenous fibrinogen supplementation had increased plasma fibrinogen concentration versus controls (171 ± 19 vs. 63 ± 10 mg/dl [mean ± SD for Multifibren U]; 185 ± 30 vs. 41 ± 4 mg/dl [Thrombin reagent]; P &lt; 0.05 for both comparisons). The between-group difference in plasma fibrinogen concentration diminished thereafter, with maximum concentrations in both groups observed at approximately 24 h, that is, during the acute-phase reaction after trauma. Fibrinogen supplementation did not down-regulate endogenous fibrinogen synthesis (no between-group differences in fibrinogen messenger RNA). Total postinjury blood loss was significantly lower in the fibrinogen group (1,062 ± 216 vs. 1,643 ± 244 ml; P &lt; 0.001). No signs of thromboembolism were observed.

Conclusions:

Administration of human fibrinogen concentrate did not down-regulate endogenous porcine fibrinogen synthesis. The effect on plasma fibrinogen concentration was most pronounced at 20 min but nonsignificant at approximately 24 h.

The Efficacy of Amicar Versus Tranexamic Acid in Pediatric Spinal Deformity Surgery: A Prospective, Randomized, Double-Blinded Pilot Study

STUDY DESIGN

Single-center, prospective, randomized, double-blinded trial.

OBJECTIVES

To compare blood loss, allogenic transfusion requirements, and coagulation parameters between pediatric spinal deformity patients receiving aminocaproic acid (Amicar) or tranexamic acid (TXA) during posterior spinal fusion.

SUMMARY OF BACKGROUND DATA

Amicar and TXA have been shown to decrease blood loss in pediatric spinal deformity cases compared with controls. The difference in efficacy between these medications in this population has not been reported.

METHODS

Enrolled patients were randomized to receive either Amicar or TXA during scoliosis surgery. Baseline demographic and deformity comparisons were collected. Intraoperative comparisons included estimated and calculated blood loss, number of levels instrumented, number of osteotomies, operative time, and allogenic transfusion requirements. Preoperative and postoperative hemoglobin, platelets, prothrombin time, partial prothrombin time (PTT), international normalized ratio (INR), and fibrinogen were recorded.

RESULTS

A total of 47 patients were enrolled with data available for review (N = 25, Amicar; N = 22, TXA). No difference in cohorts was found in demographics, preoperative hemoglobin, platelets, prothrombin time, PTT, INR, initial Cobb angle, average number of: levels fused, patients with osteotomies and osteotomies, operative time, and final Cobb angles. Estimated blood loss was significantly less (about 221 mL) than the calculated blood loss in both groups (p = .003). Estimated blood loss (1,088 vs. 726 mL; p = .055) and calculated blood loss (1,366 vs. 903 mL; p = .13) trended higher in the Amicar group. Although no difference in allogenic transfusion rates (20% vs. 14%) was observed, average volumes transfused were significantly higher in the Amicar cohort (1,014 vs. 461 mL; p = .03). The TXA cohort demonstrated a statistically significant smaller change in INR, a lower PTT, and greater fibrinogen levels postoperatively.

CONCLUSIONS

Compared with Amicar, TXA use was associated with a lower allogenic transfusion requirement, less alteration in postoperative clotting studies, and a trend toward lower blood loss in pediatric posterior spinal fusion patients.

Idiopathic intracranial hypertension following spinal deformity surgery in children

Idiopathic intracranial hypertension (IIH) after pediatric spinal deformity surgery has not been previously reported. The authors conducted a retrospective analysis of more than 1500 pediatric spinal surgeries performed between 1992 and 2011. From their analysis, they report on 3 adolescent patients who underwent uncomplicated segmental spinal instrumentation for pediatric spinal deformity correction and subsequently developed features of IIH. The common variables in these 3 patients were adolescent age, spinal deformity, being overweight, symptom onset within 2 weeks postoperatively, significant estimated blood loss, and intraoperative use of ε-aminocaproic acid (antifibrinolytic) injection. The authors postulate that the development of IIH could be the result of venous outflow obstruction due to derangement of the epidural venous plexus during surgery. The use of ε-aminocaproic acid could potentially have the risk of causing IIH, probably mediated through hyperfibrinogenemia, although there have not been published cases in the neurosurgical, orthopedic, cardiac, or general surgical literature. Idiopathic intracranial hypertension after spinal deformity correction is a condition that should be recognized by neurosurgeons and orthopedic surgeons, because appropriate intervention with early medical therapy can lead to a satisfactory clinical outcome.

Management of bleeding following major trauma: an updated European guideline

INTRODUCTION

Evidence-based recommendations are needed to guide the acute management of the bleeding trauma patient, which when implemented may improve patient outcomes.

METHODS

The multidisciplinary Task Force for Advanced Bleeding Care in Trauma was formed in 2005 with the aim of developing a guideline for the management of bleeding following severe injury. This document presents an updated version of the guideline published by the group in 2007. Recommendations were formulated using a nominal group process, the Grading of Recommendations Assessment, Development and Evaluation (GRADE) hierarchy of evidence and based on a systematic review of published literature.

RESULTS

Key changes encompassed in this version of the guideline include new recommendations on coagulation support and monitoring and the appropriate use of local haemostatic measures, tourniquets, calcium and desmopressin in the bleeding trauma patient. The remaining recommendations have been reevaluated and graded based on literature published since the last edition of the guideline. Consideration was also given to changes in clinical practice that have taken place during this time period as a result of both new evidence and changes in the general availability of relevant agents and technologies.

CONCLUSIONS

This guideline provides an evidence-based multidisciplinary approach to the management of critically injured bleeding trauma patients.

Role of Amicar in surgery for neuromuscular scoliosis

STUDY DESIGN

A retrospective case-control study.

OBJECTIVE

Evaluate the effectiveness of Amicar in decreasing perioperative blood loss in patients with neuromuscular scoliosis undergoing posterior spinal fusion (PSF) and segmental spinal instrumentation (SSI).

SUMMARY OF BACKGROUND DATA

Previously, a preliminary prospective; prospective randomized double-blind; same-day anterior and posterior spinal fusion; and fibrinogen studies have demonstrated Amicar to be effective in decreasing total perioperative blood loss and transfusion requirements in surgery for idiopathic scoliosis. Increased fibrinogen secretion is a possible explanation. We are now analyzing its effectiveness in neuromuscular scoliosis.

METHODS

Amicar was administered at 100 mg/kg over 15 minute not to exceed 5 g after anesthesia induction. Maintenance is 10 mg/kg/h until wound closure. There were 2 study groups: group 1 (n = 34), no Amicar and group 2 (n = 62) who received Amicar. The majority of patients in both groups had cerebral palsy. Total perioperative blood loss was determined from the estimated intraoperative blood loss and measured postoperative suction drainage. Total perioperative blood loss and transfusion requirements (cell saver and allogeneic) were compared using chi or Fisher exact test.

RESULTS

There was statistically less estimated intraoperative blood loss, total perioperative blood loss, and transfusion requirements in group 2. Postoperative suction drainage was also less but did not reach statistical significance. In group 1, estimated intraoperative blood loss, measured postoperative suction drainage, and total perioperative blood loss were 2194 +/- 1626 mL, 903 +/- 547 mL, and 3055 +/- 1852 mL, whereas in group 2, it was 1125 +/- 715 mL, 695 +/- 489 mL, and 1805 +/- 940 mL. Transfusion requirements were 1548 +/- 962 mL in group 1 but only 660 +/- 589 mL in group 2 (P < 0.0001). Amicar was equally effective in all diagnoses. There were no complications related to the use of Amicar.

CONCLUSION

Amicar was highly effective in decreasing perioperative blood loss and transfusion requirements in patients with neuromuscular scoliosis undergoing PSF and SSI. It was most effective in decreasing estimated intraoperative blood loss. This results in decreased transfusion requirements, costs, and potential transfusion-related complications.

The role of Amicar in same-day anterior and posterior spinal fusion for idiopathic scoliosis

STUDY DESIGN

A retrospective study of the effectiveness of Amicar (epsilon aminocaproic acid).

OBJECTIVE

Evaluate the effectiveness of Amicar in decreasing perioperative blood loss and transfusion requirements in same-day anterior (ASF) and posterior spinal fusion (PSF) with segmental spinal instrumentation (SSI) for idiopathic scoliosis.

SUMMARY OF BACKGROUND DATA

Preliminary prospective, prospective randomized double-blind, and fibrinogen studies have demonstrated Amicar to be effective in decreasing perioperative blood loss in patients with idiopathic scoliosis undergoing PSF with SSI. Increased fibrinogen secretion is a possible explanation.

METHODS

There were 73 consecutive patients divided into 3 study groups based on the administration of Amicar: Group 1 (n = 16), no Amicar; Group 2 (n = 18), Amicar for the PSF with SSI only; and Group 3 (n = 39), Amicar for both ASF and PSF with SSI. All patients were managed using the same general anesthesia technique, intraoperative procedure, postoperative care path, and indications for transfusion (hemoglobin <7 g/dL). Total perioperative blood loss (estimated intraoperative blood loss for both procedures and measured postoperative chest tube and PSF wound suction drainage) and total transfusion requirements between groups were compared using one-way ANOVA.

RESULTS

There were statistically significant decreases in mean estimated intraoperative PSF with SSI, total perioperative blood loss, and transfusion requirements in the 2 Amicar groups. However, Amicar had no significant effect on estimated intraoperative ASF blood loss, chest tube drainage, or PSF wound suction drainage. Total perioperative blood loss and transfusion requirements (cell saver, autologous, directed, and allogeneic blood) were: 3442.8 +/- 1344.0 mL and 1537.1 +/- 905.1 mL in Group 1; 2089.8 +/- 684.0 mL and 485.2 +/- 349.8 mL in Group 2; and 2184.1 +/- 1163.7 mL and 531.5 +/- 510.5 mL in Group 3. There were no Amicar related complications.

CONCLUSION

Amicar was highly effective in decreasing total perioperative blood loss and transfusion requirements in same-day ASF and PSF with SSI for idiopathic scoliosis. It results in less preoperative autologous blood donation, perioperative blood transfusion, costs, and potential transfusion-related complications. It was most effective in decreasing intraoperative estimated PSF with SSI blood loss. It had no significant effect during the ASF, postoperative chest tube, or PSF wound suction drainage. We now recommend that it be used for the PSF with SSI procedure only.

Adolescent idiopathic scoliosis (AIS) - an indication for surgery? A systematic review of the literature

PURPOSE

Historically, the treatment options for AIS, the most common form of scoliosis are: Exercises, in-patient rehabilitation, braces and surgery. While there is evidence in the form of prospective controlled studies that Scoliosis Intensive Rehabilitation (SIR) and braces can alter the natural history of the condition, there is no review on prospective controlled trials for surgical treatment. The aim of this review was to perform a systematic search of the Pub Med literature to reveal the evidence on scoliosis surgery.

METHODS

A systematic review has been performed using the Pub Med database. Literature has been searched for the outcome parameter; 'rate of progression' and only prospective controlled studies that have considered the treatment versus the natural history have been included.

RESULTS

No controlled study, not in the short, mid or long term, searched within the review, has been found to reveal evidence to support the hypothesis that the effects of surgery as a treatment option for AIS is superior to natural history.

CONCLUSIONS

No evidence has been found in terms of prospective controlled studies to support surgical intervention from the medical point of view. In the light of the unknown long-term effects of surgery and in concluding on the lack of evidence already found that surgery might change the signs and symptoms of scoliosis, a randomized controlled trial (RCT) is long overdue. Until such a time that such evidence exists, there can be no medical indication for surgery. The indications for surgery are limited for cosmetic reasons in severe cases and only if the patient and the family agree with this.

Antifibrinolytic agents for reducing blood loss in scoliosis surgery in children

BACKGROUND

Scoliosis surgery is often associated with substantial blood loss and potential detrimental effects in children. Antifibrinolytic agents are often used to reduce perioperative blood loss. Clinical trials have evaluated their effect in children undergoing surgical correction of scoliosis but no systematic review has been published. We performed a systematic review on the efficacy and safety of antifibrinolytic drugs in children undergoing scoliosis surgery.

OBJECTIVES

To assess the efficacy and safety of aprotinin, tranexamic acid and aminocaproic acid in reducing blood loss and transfusion requirements in children undergoing scoliosis surgery.

SEARCH STRATEGY

We searched CENTRAL (The Cochrane Library 2007, Issue 3), OVID MEDLINE (1950 to September 3rd 2007), LILACS (1992 to June 20th 2007) and EMBASE (1980 to July 23rd 2007). We also searched conference proceedings from 2003 to 2007 and the clinicaltrials.gov registry. No language restriction was applied.

SELECTION CRITERIA

We included blinded or unblinded randomized controlled trials that evaluated the effect of antifibrinolytics on perioperative blood loss in children that were 18 years of age or younger and undergoing scoliosis surgery.

DATA COLLECTION AND ANALYSIS

Two authors independently performed the data extraction. Primary outcomes were mortality and number of patients transfused. Secondary outcomes were number of patients transfused with allogeneic blood, amount of total blood transfused, total blood loss and adverse events. To assess heterogeneity we used the I(2) test and for the quantitative analysis we used a fixed-effect model.

MAIN RESULTS

Six studies fulfilled the inclusion criteria. The total number of participants was 254, of whom 127 were allocated to placebo and 127 to antifibrinolytic drugs. Aprotinin, tranexamic acid and aminocaproic acid were evaluated in two studies each. All studies had placebo as the control group intervention. There were no deaths or any serious adverse events in any study, in either the active or the control group. The risk of being transfused was similar in patients receiving antifibrinolytic drugs or placebo. Antifibrinolytics drugs decreased the amount of blood transfused by 327 ml (95% CI -469.04 to -185.78) and the amount of blood loss by 427 ml (95% CI -602.51 to -250.56). There was no indication of publication bias, however, we cannot rule it out due to the small number of studies included.

AUTHORS' CONCLUSIONS

The effect of antifibrinolytic drugs on mortality could not be assessed. Antifibrinolytic drugs reduced blood loss and the amount of blood transfused in children undergoing scoliosis surgery; however, their effect on the number of children requiring blood transfusion remains unclear. Aprotinin, tranexamic acid and aminocaproic acid seem to be similarly effective.