Blood conservation and pain control in scoliosis corrective surgery: an online survey of UK practice

A survey of patient blood management for patients undergoing cardiac surgery in nine European countries

STUDY OBJECTIVE

To describe and compare patient blood management (PBM) practices in cardiac surgery in nine European countries and identify the main risk factors for bleeding or transfusion according to the surveyed centres.

DESIGN

We set up an online survey to evaluate PBM practices in two clinical scenarios, risk factors for bleeding or transfusion, and previous experience with antifibrinolytics.

SETTING

This survey was completed by European anesthesiologists in 2019.

PATIENTS

No patients were included in the survey.

INTERVENTION

None.

MEASUREMENTS

We evaluated the degree of implementation of PBM practices in patients undergoing cardiac surgery.

MAIN RESULTS

Ninety-eight of 177 responses (38%) were complete with variable response rates by country. In a non-emergent situation, no respondents would transfuse red cells preoperatively in an anaemic patient, while cell salvage (89%) and antifibrinolytics (82%) would almost always be used. Optimization of Hemoglobin level (36%) and use of off-pump techniques (34%), minimally invasive surgery (25%) and relatively recently-developed CPB technologies such as mini-bypass (32%) and autologous priming (38%), varied greatly across countries. In an emergent clinical situation, topical haemostatic agents would frequently be used (61%). Tranexamic acid (72%) and aprotinin (20%) were the main antifibrinolytics used, with method of administration and dose varying markedly across countries. Five factors were considered to increase risk of bleeding or transfusion by at least 90% of respondents: pre-operative anaemia, prior cardiac surgery, clopidogrel 5 days or less before surgery, use of other P2Y12 inhibitors at any point, and thrombocytopenia <100.10⁹ platelets/mm³.

CONCLUSION

PBM guidelines are not universally implemented in European cardiac surgery centres or countries, resulting in discrepancies in techniques and products used for a given clinical situation.

Do Antifibrinolytic Agents Reduce the Risk of Blood Transfusion in Children Undergoing Spinal Fusion?: A Propensity Score-matched Comparison Using a National Database

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

To evaluate the effectiveness and safety of antifibrinolytic (AF) agents in reducing perioperative blood transfusion in pediatric patients undergoing spinal fusion.

SUMMARY OF BACKGROUND DATA

The potential for AF to decrease bleeding and reduce exposure to allogenic transfusions has led to widespread off-label use in a number of major pediatric surgical procedures. Recent reviews call for improving the body of evidence for their effectiveness and safety in pediatric spinal fusion.

METHODS

Children undergoing spinal fusion were identified in the American College of Surgeons National Surgical Quality Improvement Program Pediatric (NSQIP-P) 2016 and 2017 databases. Univariate analyses of patient and perioperative characteristics informed the creation of a propensity score model predicting treatment with AF, followed by 1:1 matching to allow comparison of allogenic red blood cell transfusion rates and secondary outcomes between treated and untreated patients.

RESULTS

Of 6626 total patients, 5434 (81%) received AF and 1533 (23%) received a blood transfusion. Analysis of data for 1192 propensity score-matched pairs revealed that treatment with AF was associated with a statistically nonsignificant 16% reduction in perioperative transfusion (OR 0.84, 95% confidence interval 0.68-1.05, P = 0.119) and a statistically significant 43% reduction in postoperative transfusion (OR 0.57, 95% confidence interval 0.39-0.81, P = 0.002). No differences in the incidences of postoperative seizure or thrombosis were observed, with overall rates of 7.5 and 22.5 events per 10,000 patients, respectively.

CONCLUSION

AF agents appear to reduce postoperative allogenic transfusion in children undergoing spinal fusion surgery. Adverse drug effects such as thromboembolic complications and seizure were extremely rare and warrant continued monitoring, though this is the largest study to date providing evidence for the safety profile of these drugs.

LEVEL OF EVIDENCE

3.

Antifibrinolytic Drugs and Allogeneic Transfusion in Pediatric Multilevel Spine Surgery: A Propensity Score Matched Cohort Study

STUDY DESIGN

Observational cohort study with propensity score matching.

OBJECTIVE

Determine whether antifibrinolytic drug use is associated with decreased allogeneic blood transfusion in multilevel pediatric spine surgery.

SUMMARY OF BACKGROUND DATA

Antifibrinolytic drugs are commonly used in adult multilevel spine surgery to reduce blood loss and allogeneic transfusion; however, only small studies have examined their efficacy in pediatric patients having multilevel spine surgery.

METHODS

Pediatric patients who had posterior multilevel spine surgery between 2016 and 2017 were identified in the national surgery quality improvement program participant use file. Propensity score matching was used to reduce bias from confounding and the rate of intraoperative allogeneic transfusion was compared between patients who received antifibrinolytic drugs and those who did not. Secondary outcomes included intraoperative cell saver volume, postoperative allogeneic transfusion, massive intraoperative transfusion, and adverse events including venous thromboembolism and seizure.

RESULTS

A total of 6904 patients underwent posterior multilevel spine surgery during the study period and 83% received antifibrinolytics. The matched cohort included 604 patients. Antifibrinolytic use had no association with reduced intraoperative allogeneic transfusion: odds ratio (OR) = 0.71 (99% confidence interval [CI] = 0.40-1.26, P = 0.12) or cell saver volume, median volume = 114 mL (0, 250 mL) in antifibrinolytic group versus 100 mL (0, 246 mL) in control group, P = 0.04. There was also no association with reduced postoperative allogeneic transfusion OR = 1.23 (99% CI = 0.54-2.81, P = 0.52) or massive transfusion OR = 1.0 (99% CI = 0.34-2.92, P = 1.0). No patient in the matched cohort had a venous thromboembolism or seizure.

CONCLUSION

Antifibrinolytic drugs are commonly used in pediatric multilevel spine surgery in the United States, but no efficacy was demonstrated in our study. There were no venous thromboembolisms or seizures implying an excellent safety profile in pediatric patients.

LEVEL OF EVIDENCE

3.

Postoperative pain management in patients undergoing posterior spinal fusion for adolescent idiopathic scoliosis: a narrative review

Posterior spinal fusion for adolescent idiopathic scoliosis is one of the most invasive surgical procedures performed in children and adolescents. Because of the extensive surgical incision and massive tissue trauma, posterior spinal fusion causes severe postoperative pain. Intravenous patient-controlled analgesia with opioids has been the mainstay of postoperative pain management in these patients. However, the use of systemic opioids is sometimes limited by opioid-related side effects, resulting in poor analgesia. To improve pain management while reducing opioid consumption and opioid-related complications, concurrent use of analgesics and analgesic modalities with different mechanisms of action seems to be rational. The efficacy of intrathecal opioids and nonsteroidal anti-inflammatory drugs as components of multimodal analgesia in scoliosis surgery has been well established. However, there is either controversy or insufficient evidence regarding the use of other analgesic methods, such as continuous ketamine infusion, perioperative oral gabapentin, acetaminophen, continuous wound infiltration of local anesthetics, a single dose of systemic dexamethasone, and lidocaine infusion in this patient population. Moreover, appropriate combinations of analgesics have not been established. The aim of this literature review is to provide detailed information of each analgesic technique so that clinicians can make appropriate choices regarding pain management in patients with adolescent idiopathic scoliosis undergoing posterior spinal fusion.

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.

Assessing the Rates, Predictors, and Complications of Blood Transfusion Volume in Posterior Arthrodesis for Adolescent Idiopathic Scoliosis

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To determine predictors of and 30-day complications associated with blood transfusion volume after posterior spinal fusion for adolescent idiopathic scoliosis (AIS).

SUMMARY OF BACKGROUND DATA

Posterior arthrodesis is a common procedure performed for AIS, and patients frequently require perioperative blood transfusions. Few studies, however, have examined the rates and potential complications associated with blood transfusion volume.

METHODS

Patients undergoing posterior arthrodesis for AIS were selected from the National Surgical Quality Improvement Program pediatric database from 2012 to 2013. Patients were stratified on the basis of blood transfusion volume and patient demographics and comorbidities, operative characteristics, and 30-day complications were recorded. Multivariate analyses were performed to determine predictors of transfusion as well as the effect of transfusion volume on 30-day complication rates.

RESULTS

A total of 1691 patients were included. Male sex (P = 0.010), esophageal or gastrointestinal disease (P = 0.016), cardiac risk factors (P = 0.037), preoperative inotrope requirement (P = 0.031), total operative time of 300 minutes or more (P < 0.001), and posterior arthrodesis of 13 or more vertebral segments (P < 0.001) were independent risk factors for requiring blood transfusion. Total transfusion volume of 20 mL/kg or more was the minimum volume independently associated with increased rates of total complications (P = 0.018), with a complication rate of 5.9%.

CONCLUSION

We present the first large, comprehensive analysis of complications related to blood transfusion events and transfusion volume on short-term postoperative complications after posterior arthrodesis for AIS. Although transfusion in general is not associated with 30-day adverse events, a volume of 20 mL/kg was associated with higher complication rates.

LEVEL OF EVIDENCE

4.

Implementation of a patient blood management program in pediatric scoliosis surgery

OBJECTIVES

To determine whether the implementation of a blood conservation program, and the adoption and progressive association of different methods, reduces transfusion requirements in pediatric patients undergoing scoliosis surgery of different origins.

MATERIAL AND METHOD

Quasi-experimental, nonrandomized, descriptive study, approved by the Ethics Committee for Research of our institution. 50 pediatric patients (ASA I-III) aged 5 to 18 years, undergoing scoliosis surgery of any etiology by a single posterior or double approach (anterior and posterior) were included. A historical group with no alternatives to transfusion: Group No ahorro=15 patients (retrospective data collection) was compared with another 3 prospective study groups: Group HNA (acute normovolemic hemodilution)=9 patients; Group HNA+Rec (intraoperative blood salvage)=14 patients, and Group EPO (HNA+Rec+erythropoietin±preoperative donation)=12 patients; according with the implementation schedule of the transfusion alternatives in our institution.

RESULTS

The rate of transfusion in different groups (No ahorro, HNA, HNA+Rec, EPO) was 100, 66, 57, and 0% of the patients, respectively, with a mean±SD of 3.40±1.59; 1.33±1.41; 1.43±1.50; 0±0 RBC units transfused per patient, respectively. Statistically significant differences (P<.001) were found in both the transfusion rate and number of RBC units.

CONCLUSIONS

The application of a multimodal blood transfusion alternatives program, individualized for each pediatric patient undergoing scoliosis surgery can avoid transfusion in all cases.

The efficacy of antifibrinolytic drugs in children undergoing noncardiac surgery: a systematic review of the literature

Children undergoing major surgery are frequently exposed to a high risk of blood loss often requiring transfusion. Although the risks associated with blood product transfusion have considerably decreased over the last decade, transfusion is still associated with significant morbidity and mortality. Thus, rigorous efforts should be made to decrease surgical bleeding and the need for blood product transfusion. Antifibrinolytic drugs have been shown to be effective when used in both adult and pediatric surgical patients. While there are data in adults to support safety, data remain limited for pediatric patients. Since the restriction of aprotinin use in 2008, the most commonly used antifibrinolytic drugs have been the lysine analogs, tranexamic acid (TXA), and ε-aminocaproic acid, which inhibit the conversion of plasminogen to plasmin and decrease the degree of fibrinolysis. We performed a systematic review of the literature pertaining to the efficacy of antifibrinolytic drugs in children undergoing noncardiac surgery. During spine surgery, both TXA and ε-aminocaproic acid decrease blood loss and transfusion requirements; however, this information comes from small, mainly retrospective trials. Two prospective, randomized, controlled trials have tested the efficacy of TXA in children undergoing craniofacial surgery and have reported that TXA decreases transfusion requirements. Two pharmacokinetic trials were also recently published and are summarized in this review. No data have been published regarding the efficacy of TXA administration in the pediatric trauma population. Further data are still needed in this field of study, and we discuss some perspectives for future research.

Sources of information influencing decision-making in orthopaedic surgery - an international online survey of 1147 orthopaedic surgeons

Background

Manufacturers of implants and materials in the field of orthopaedics use significant amounts of funding to produce informational material to influence the decision-making process of orthopaedic surgeons with regards to choice between novel implants and techniques. It remains unclear how far orthopaedic surgeons are really influenced by the materials supplied by companies or whether other, evidence-based publications have a higher impact on their decision-making. The objective was to evaluate the subjective usefulness and usage of different sources of information upon which orthopaedic surgeons base their decisions when acquiring new implants or techniques.

Methods

We undertook an online survey of 1174 orthopaedic surgeons worldwide (of whom n = 305 were head of their department). The questionnaire included 34 items. Sequences were randomized to reduce possible bias. Questions were closed or semi-open with single or multiple answers. The usage and relevance of different sources of information when learning about and selecting orthopaedic treatments were evaluated. Orthopaedic surgeons and trainees were targeted, and were only allowed to respond once over a period of two weeks. Baseline information included country of workplace, level of experience and orthopaedic subspecialisation. The results were statistically evaluated.

Results

Independent scientific proof had the highest influence on decisions for treatment while OEM (Original Equipment Manufacturer) driven activities like newsletters, white papers or workshops had the least impact. Comparison of answers from the three best-represented countries in this study (Germany, UK and USA) showed some significant differences: Scientific literature and congresses are significantly more important in the US than in the UK or Germany, although they are very important in all countries.

Conclusions

Independent and peer-reviewed sources of information are preferred by surgeons when choosing between methods and implants. Manufacturers of medical devices in orthopaedics employ a considerable workforce to inform or influence hospital managers and leading doctors with marketing activities. Our results indicate that it might be far more effective to channel at least some of these funds into peer-reviewed research projects, thereby assuring significantly higher acceptance of the related products.