Screening for deep venous thrombosis after idiopathic scoliosis surgery in children: a pilot study

Screening and Prophylaxis for Venous Thromboembolism in Pediatric Surgery: A Systematic Review

OBJECTIVE

The American Pediatric Surgical Association Outcomes and Evidence-Based Practice Committee conducted a systematic review to describe the epidemiology of venous thromboembolism (VTE) in pediatric surgical and trauma patients and develop recommendations for screening and prophylaxis.

METHODS

The Medline (Ovid), Embase, Cochrane, and Web of Science databases were queried from January 2000 through December 2021. Search terms addressed the following topics: incidence, ultrasound screening, and mechanical and pharmacologic prophylaxis. The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines were followed. Consensus recommendations were derived based on the best available literature.

RESULTS

One hundred twenty-four studies were included. The incidence of VTE in pediatric surgical populations is 0.29% (Range = 0.1%-0.48%) and directly correlates with surgery type, transfusion, prolonged anesthesia, malignancy, congenital heart disease, inflammatory bowel disease, infection, and female sex. The incidence of VTE in pediatric trauma populations is 0.25% (Range = 0.1%-0.8%) and directly correlates with injury severity, major surgery, central line placement, body mass index, spinal cord injury, and length-of-stay. Routine ultrasound screening for VTE is not recommended. Consider sequential compression devices in at-risk nonmobile, pediatric surgical patients when an appropriate sized device is available. Consider mechanical prophylaxis alone or with pharmacologic prophylaxis in adolescents >15 y and post-pubertal children <15 y with injury severity scores >25. When utilizing pharmacologic prophylaxis, low molecular weight heparin is superior to unfractionated heparin.

CONCLUSIONS

While VTE remains an infrequent complication in children, consideration of mechanical and pharmacologic prophylaxis is appropriate in certain populations.

TYPE OF STUDY

Systematic Review of level 2-4 studies.

LEVEL OF EVIDENCE

Level 3-4.

Lower Limb Deep Venous Thrombosis After Posterior Spinal Fusion as an Initial Manifestation of Factor V Leiden Mutation in a Pediatric Patient: A Case Report

Deep venous thrombosis (DVT) is a serious condition in which a blood clot forms in a deep vein, usually of the lower extremity. In pediatric orthopedic surgery, the incidence of thrombotic events is rare. This is a case presentation of a 12-year-old female patient without previous events or a family history of thrombotic events who underwent a posterior spinal fusion due to severe adolescent idiopathic scoliosis. The patient developed a DVT due to an underlying Factor V Leiden mutation. The purpose of this case report is to create awareness, facilitate the diagnosis and management, and aid in future interventions and clinical outcomes.

Pediatric Orthopaedic Venous Thromboembolism: A Systematic Review Investigating Incidence, Risk Factors, and Outcome

Background

There is growing evidence of increased venous thromboembolism (VTE) incidence in children with trauma or infection. The purpose of this study was to conduct a systematic review of existing literature related to VTE in the pediatric orthopaedic population, to estimate the overall incidence of VTE and identify risk factors associated with this condition.

Methods

A systematic review of the available literature was performed to identify articles that described VTE in pediatric orthopaedic surgery or admission. Literature queries were performed to identify articles published from 1980 to 2021 that included patients ≤21 years of age. A stepwise search strategy of 5 electronic databases yielded 1,426 articles, which were filtered by 2 reviewers to identify 30 articles for full-text review. The primary aim was to determine the rate of VTE, and the secondary aim was to identify risk factors for VTE. The pooled incidence of VTE was estimated and reported in cases per 10,000. Studies were stratified by study size, by trauma versus elective surgery, and by orthopaedic subspecialty.

Results

The 30 articles reported 3,113 VTE events in 2,467,764 pediatric patients (including those with non-orthopaedic conditions), for a pooled VTE incidence of 20 events (95% confidence interval [CI] = 10.8 to 37.2) per 10,000. Four of the studies were excluded for incomplete data or high heterogeneity. The remaining 26 studies had 850,268 orthopaedic patients with 1,108 cases of VTE, for a pooled VTE incidence of 16.6 events (95% CI = 9.1 to 30.5) per 10,000. Studies with <10,000 patients and those involving a diagnosis of trauma had the highest VTE incidence when stratification was performed. The most frequently analyzed risk factors in 15 available studies included age, sex, obesity/body mass index, type of surgery, and use of a central venous catheter.

Conclusions

This systematic review indicated that the risk of VTE associated with pediatric orthopaedic surgery or admission remains low, at <17 events per 10,000 cases. However, orthopaedic surgeons should be aware of the most common risk factors associated with pediatric orthopaedic VTE and should pay special attention to traumatic etiologies, as these yielded the highest incidence.

Levels of Evidence

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Venous Thromboembolism Risk and Thromboprophylaxis in Pediatric Neurosurgery and Spinal Injury: Current Trends and Literature Review

Although the entities of venous thromboembolism (VTE), deep venous thrombosis, pulmonary embolus, and thromboprophylaxis in adult patients undergoing brain tumor and spine surgery, traumatic brain injury and elective neurosurgical procedures are widely elucidated, the same is not valid when pediatric patients are under consideration. An attempt to review the peculiarities of these patients through a comprehensive bibliographic review is undertaken. We performed a narrative summary of the relevant literature dedicated to pediatric patients, centered on traumatic brain injury, the general incidence of thromboembolic disease in this patient population, the role of low molecular weight heparin (LMWH) in the treatment and prophylaxis of VTE, and its role in elective neurosurgical procedures, including spinal operations. Additionally, the risk of deep venous thrombosis in elective neurosurgical procedures is reviewed. Due to inherent limitations of the current studies, particularly a restricted number of patients, our data are underpowered to give a definitive protocol and guidelines for all the affected patients. Our current conclusions, based only on pediatric patients, argue that there is limited risk of VTE in pediatric patients suffering from brain tumors and that the possibility of VTE is very low in children undergoing elective neurosurgical procedures. There is no consensus regarding the exact incidence of VTE in traumatic brain injury patients. LMWH seems to be a safe and effective choice for the "at risk" pediatric patient population defined as being older than 15 years, venous catheterization, nonaccidental trauma, increased length of hospital stays, orthopaedic (including spinal) surgery, and cranial surgery.

Is There Value in Venous Thromboembolism Chemoprophylaxis After Pediatric Scoliosis Surgery? A 28-Year Single Center Study

BACKGROUND

With a recognized increase in the incidence of venous thromboembolism (VTE) in children, especially in those with complex, chronic conditions, it is important for patient safety and risk management to identify subgroups that would benefit from prophylactic treatment. The aim of our study was to assess whether scoliosis surgery in children was associated with an increased incidence of VTE, including deep venous thrombosis (DVT) and pulmonary embolism, and if chemoprophylaxis is warranted.

METHODS

We reviewed our institution's Pediatric Orthopaedic Spine Database (1992-2019) to identify patients who had a symptomatic VTE postoperatively.

RESULTS

There were 1471 patients (1035 female, 436 male) with a mean age at surgery of 12.1±3.2 years (range, 1 to 18 y) underwent posterior spinal fusion and instrumentation (2131 procedures). No patients were given pharmacological VTE prophylaxis, and no routine screening for VTE was performed. Two patients had a lower extremity DVT (0.13%) within 6 months following surgery, (range, 55 to 161 d). Neither patient had a subsequent pulmonary embolism. They were 9 and 17 years of age with a diagnosis of neuromuscular scoliosis (1 each postpolio and myelodysplasia). One affected patient had a central venous line inserted perioperatively, a known risk factor for thromboembolism. All DVTs were treated with appropriately dosed anticoagulants. None had a family history of hypercoagulation.

CONCLUSIONS

The risk of symptomatic VTE is extraordinarily low after pediatric spinal deformity surgery. Mechanical prophylaxis is sufficient in most cases. Further multi-center studies may help identify patient specific risk factors.

The risks, reasons, and costs for 30- and 90-day readmissions after fusion surgery for adolescent idiopathic scoliosis

OBJECTIVE

With the continued evolution of bundled payment plans, there has been a greater focus within orthopedic surgery on quality metrics up to 90 days of care. Although the Centers for Medicare and Medicaid Services does not currently penalize hospitals based on their pediatric readmission rates, it is important to understand the drivers for unplanned readmission to improve the quality of care and reduce costs.

METHODS

The National Readmission Database provides a nationally representative sample of all discharges from US hospitals and allows follow-up across hospitals up to 1 calendar year. Adolescents (age 10-18 years) who underwent idiopathic scoliosis surgery from 2012 to 2015 were included. Patients were separated into those with and those without readmission within 30 days or between 31 and 90 days. Demographics, operative conditions, hospital factors, and surgical outcomes were compared using the chi-square test and t-test. Independent predictors for readmissions were identified using stepwise multivariate logistic regression.

RESULTS

A total of 30,677 patients underwent adolescent idiopathic scoliosis surgery from 2012 to 2015. The rates of 30- and 90-day readmissions were 2.9% and 1.4%, respectively. The mean costs associated with the index admission and 30- and 90-day readmissions were $60,680, $23,567, and $16,916, respectively. Common risk factors for readmissions included length of stay > 5 days, obesity, neurological disorders, and chronic use of antiplatelets or anticoagulants. The index admission complications associated with readmissions were unintended durotomy, syndrome of inappropriate antidiuretic hormone, and superior mesenteric artery syndrome. Hospital factors, discharge disposition, and operative conditions appeared to be less important for readmission risk. The top reasons for 30-day and 90-day readmissions were wound infection (34.7%) and implant complications (17.3%), respectively. Readmissions requiring a reoperation were significantly higher for those that occurred between 31 and 90 days after the index readmission.

CONCLUSIONS

Readmission rates were low for both 30- and 90-day readmissions for adolescent idiopathic scoliosis surgery patients. Nevertheless, readmissions are costly and appear to be associated with potentially modifiable risk factors, although some risk factors remain potentially unavoidable.

Epidemiology and outcomes of clinically unsuspected venous thromboembolism in children: A systematic review

BACKGROUND

Clinically unsuspected venous thromboembolic events (uVTE) detected during routine imaging pose a management challenge due to limited knowledge about their clinical significance. Unsuspected VTE are often referred as "asymptomatic," "incidental," or "clinically silent/occult" VTE.

OBJECTIVE

To understand the epidemiology, management, and outcomes of uVTE in children.

METHODS

A systematic review was performed according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The search criteria included controlled vocabulary and keywords for VTE, incidental findings, and children (ages ≤ 21 years).

RESULTS

Among 10 875 articles, 51 studies (8354 children with 758 uVTE) were selected. The studies were heterogeneous, I2 96%; P < .0001. Unsuspected VTE were diagnosed in two settings: first, asymptomatic VTE (aVTE) diagnosed through surveillance imaging for VTE (46 studies; n = 5894; aVTE: 715, pooled frequency: 19%, 95% confidence interval [CI]: 13%-24%); second, incidental VTE (iVTE) diagnosed during imaging performed for indications without primary suspicion for VTE (6 studies; n = 2460; iVTE: 43). The majority (94%) of aVTE were associated with central venous lines (CVL). Non-CVL settings included post-spinal surgery, post-splenectomy, trauma, nephrotic syndrome, and newborns. In general, aVTE were reported to have a benign clinical course, were mostly transient, and resolved without intervention and with few immediate or long-term functional complications. Incidental VTE were primarily detected in children with cancer and ranged from tumor-associated thrombi to pulmonary embolism (PE) with insufficient evidence to draw meaningful conclusions about their management.

CONCLUSION

Clinically uVTE were predominantly diagnosed with CVL and their outcomes were generally favorable implying limited benefit of routine surveillance and thromboprophylaxis. Prospective research is needed to clarify the optimal management of iVTE.

Incidence of venous thromboembolism in hospitalized pediatric neurosurgical patients: a retrospective 25-year institutional experience

PURPOSE

Venous thromboembolism (VTE) refers to both deep venous thrombosis (DVT) and pulmonary embolism (PE). The risk of VTE in adult neurosurgical patients is thoroughly studied. However, the incidence and risk of VTE in a comprehensive pediatric neurosurgical population is not well-defined. The available pediatric data consists of reviews of specific high-risk groups, such as trauma, critical care, or cancer patients. This may not be reflective of the entire spectrum of a high-volume pediatric neurosurgery practice. This study was undertaken to analyze the incidence and risk factors of VTE in all hospitalizations evaluated by a pediatric neurosurgery service over a 25-year period.

METHODS

A retrospective review of electronic medical records was performed for 9149 hospitalizations in 6374 unique patients evaluated by the pediatric neurosurgery service at Riley Hospital for Children (Indianapolis, IN, USA) from 1990-2014. During this time period, there was no standardized VTE prevention protocol. The study group included all patients less than 18 years of age. Patients with a known pre-existing VTE or pregnancy were excluded.

RESULTS

VTE was diagnosed in 20 of the 9149 (0.22%) hospitalizations, in 18 unique patients. All DVTs were diagnosed via Doppler ultrasound and/or computed tomography. Anatomic clot locations included 9 in the upper extremity (0.098% of hospitalizations), 8 in the lower extremity (0.087%), and 4 (0.044%) pulmonary emboli. Ten of the 20 occurred in hospitalizations where the patient underwent surgery, although the need for surgery was not a statistically significant risk factor. Sixteen of the 20 (80%) occurred in patients with at least one form of central venous line (p < 0.00001). There was one VTE-related death (0.01%).

CONCLUSIONS

In all pediatric neurosurgical patients, a VTE was found in 0.22% of hospitalizations over a 25-year span. Statistically significant risk factors for VTE included central venous line placement, paralysis, malignancy, intubation greater than 48 h, and hypercoagulable state.

Thrombotic risk in children undergoing orthopedic surgery

Children are physiologically protected against venous thromboembolism (VTE). Specific triggering events or contributing factors have been identified in the majority of reported cases, which differs from the adult pathology where 50% of the thromboses are considered "idiopathic". This is a rare disease in children with an estimated frequency of less than 1/1000. The risk is highest in neonates, then decreases and increases again around 13 years to reach the same level as adults at 16 years. The risk of VTE is clearly higher in certain situations: significant trauma, prolonged immobilization, central venous catheter, stay in intensive care unit, inherited thrombophilia, cancer, obesity, oral contraceptives, etc. Thromboprophylaxis should not be used systematically, even in adolescents. Proper hydration and early mobilization form the basis of mechanical thromboprophylaxis. A prescription is only given after careful analysis of the child's risk factors and the orthopedic context. Thrombotic risk assessment scores - which are based on expert opinion and large VTE registers but have not been evaluated in clinical studies - are currently the most reliable method to evaluate the thrombotic risk in children and to prescribe thromboprophylaxis. Low-molecular weight heparin are the most commonly used thromboprophylaxis agents in children, with good tolerance and efficacy.

Is pharmacological anticoagulant prophylaxis necessary for adolescent idiopathic scoliosis surgery?

We report the outcomes of mechanical prophylaxis and chemoprophylaxis in patients who underwent elective surgery for idiopathic adolescent scoliosis (AIS).We retrospectively studied the patients who underwent posterior spinal instrumentation for AIS. The patients were divided into three groups: Group A low-molecular-weight heparin (LMWH) started at 8 hours after surgery; Group B LMWH started at 24 hr after surgery; Group C did not receive chemoprophylaxis. The data about wound oozing, need for transfusion, preoperative and postoperative hemoglobin level, length of stay in hospital, interval from the surgery to removal of closed suction drainage tube, postoperative blood loss from closed suction drain, deep venous thrombosis (DVT), and pulmonary embolism (PE) were investigated.The mean age and Lenke classification for all the groups were similar. No DVT or PE was detected in any group. The mean blood loss from the drain was higher in Group A (400 mL) and Group B (450 mL) when compared to Group C (150 mL) (P = .001). There were more wound oozing in Groups A (5) and B (6) than in Group C (3) (P = .585). Three patients in Group B, 3 patients in Group A, and no patient in Group C had superficial infections. However, there was no statistical difference between the groups (P = .182). Postoperative hospital stay was significantly longer in Groups A (6 days) and B (6 days) then in Group C (5 days) (P = .001).Our current study claims that chemoprophylaxis is not necessary for the patients without risk factors after AIS surgery. Early mobilization and mechanoprophylaxis represents adequate prophylaxis in addition to pain management and well hydration in patients' routine treatment. The complications of chemoprophylaxis are not correlated to the initiation time of prophylaxis.

Prevention of perioperative venous thromboembolism in pediatric patients: Guidelines from the Association of Paediatric Anaesthetists of Great Britain and Ireland (APAGBI)

The Association of Paediatric Anaesthetists of Great Britain and Ireland (APAGBI) Guidelines Working Group on Thromboprophylaxis in Children has reviewed the literature and where possible provided advice on the care of children in the perioperative period. Areas reviewed include the incidence of perioperative venous thromboembolism (VTE), risk factors, evidence for mechanical and chemical prophylaxis, and complications. Safe practice of regional anesthesia with anticoagulant prophylaxis is detailed. In summary, there are few areas of strong evidence. Routine prophylaxis cannot be recommended for young children. Postpubertal adolescents (approximately 13 years and over) are at a slightly increased risk of VTE and should be assessed for prophylaxis and may warrant intervention if other risk factors are present. However, the incidence of VTE is significantly lower than in the adult population. This special interest review presents a summary and discussion of the key recommendations, a decision-making algorithm and a risk assessment chart. For the full guideline, go to www.apagbi.org.uk/publications/apa-guidelines.

Risk of deep venous thrombosis in elective neurosurgical procedures: a prospective, Doppler ultrasound-based study in children 12 years of age or younger

OBJECTIVE The risk of venous thromboembolism (VTE) from deep venous thrombosis (DVT) is significant in neurosurgical patients. VTE is considered a leading cause of preventable hospital deaths and preventing DVT is a closely monitored quality metric, often tied to accreditation, hospital ratings, and reimbursement. Adult protocols include prophylaxis with anticoagulant medications. Children's hospitals may adopt adult protocols, although the incidence of DVT and the risk or efficacy of treatment is not well defined. The incidence of DVT in children is likely less than in adults, although there is very little prospectively collected information. Most consider the risk of DVT to be extremely low in children 12 years of age or younger. However, this consideration is based on tradition and retrospective reviews of trauma databases. In this study, the authors prospectively evaluated pediatric patients undergoing a variety of elective neurosurgical procedures and performed Doppler ultrasound studies before and after surgery. METHODS A total of 100 patients were prospectively enrolled in this study. All of the patients were between the ages of 1 month and 12 years and were undergoing elective neurosurgical procedures. The 91 patients who completed the protocol received a bilateral lower-extremity Doppler ultrasound examination within 48 hours prior to surgery. Patients did not receive either medical or mechanical DVT prophylaxis during or after surgery. The ultrasound examination was repeated within 72 hours after surgery. An independent, board-certified radiologist evaluated all sonograms. We prospectively collected data, including potential risk factors, details of surgery, and details of the clinical course. All patients were followed clinically for at least 1 year. RESULTS There was no clinical or ultrasound evidence of DVT or VTE in any of the 91 patients. There was no clinical evidence of VTE in the 9 patients who did not complete the protocol. CONCLUSIONS In this prospective study, no DVTs were found in 91 patients evaluated by ultrasound and 9 patients followed clinically. While the study is underpowered to give a definitive incidence, the data suggest that the risk of DVT and VTE is very low in children undergoing elective neurosurgical procedures. Prophylactic protocols designed for adults may not apply to pediatric patients. Clinical trial registration no.: NCT02037607 (clinicaltrials.gov).

Thromboembolic complications in children after spinal fusion surgery

STUDY DESIGN

Retrospective review.

OBJECTIVE

To identify the incidence of venous thromboembolic (VTE) complications and pulmonary embolism (PE) in children undergoing spinal fusion surgery, to report associated mortality, and to analyze factors associated with their development.

SUMMARY OF BACKGROUND DATA

The incidence of these complications after pediatric spinal fusion surgery is unknown.

METHODS

The Nationwide Inpatient Sample database was queried from 2001 through 2010 to identify children (≤18 yr) who had spinal fusion surgery. Patients who had deep venous thrombosis or PE during the hospital stay were identified using appropriate International Classification of Diseases, Ninth Revision, Clinical Modification codes. Univariate and multivariate logistic regression models were used for analysis; statistical significance was set at P less than 0.05.

RESULTS

Depending on the year, the incidence of VTE in children varied from 9.6 to 38.5 events per 10,000 spinal fusions (mean: 21 events per 10,000 spinal fusions), and the incidence of PE varied from 0 to 6 events per 10,000 spinal fusions (mean: 2 events per 10,000 spinal fusions); there were no in-hospital VTE-associated mortalities. On multivariate logistic regression analysis, only patient diagnosis was found to be significantly associated with VTE development. VTE incidence was significantly higher in children with congenital scoliosis, syndromic scoliosis/kyphoscoliosis, and thoracolumbar fractures than in children with idiopathic scoliosis (odds ratios: 4.21, 7.14, and 12.59, respectively). On univariate analysis, in addition to diagnosis, age was also found to be significantly associated with VTE development. For each year of age, the VTE incidence increased 1.37-fold (P < 0.01).

CONCLUSION

The incidence of thromboembolic complications in children was approximately 21 events per 10,000 spinal fusions. A higher incidence of VTE in children was associated with older age and certain diagnoses (congenital scoliosis, syndromic scoliosis/kyphoscoliosis, and thoracolumbar fractures). PE in children was rare and not associated with fatality.

Alterations in the Coagulation System during Major Visceral Surgery in Children

Purpose. The description of the alterations in the hemostatic system in children undergoing abdominal surgery is sparse. Enhanced clinical outcomes for previously untreatable conditions have led to an increased incidence of venous thromboembolic complications. Alterations in children's coagulation system during major abdominal operations compared to minor procedures were examined. Methods. Children (0–12 years) undergoing either laparotomy, thoracotomy, or minor surgery were included. Participants were divided into two groups: group 1 was open laparotomy including operations for solid abdominal tumours and thoracotomy, while group 2 was minor surgery. Activated partial thromboplastin time (aPTT), D-dimer, INR, and fibrinogen were measured. Results. Both groups had a shorter aPTT, higher INR, and lower fibrinogen concentrations after the operation, while D-dimer was unaltered. The changes were, however, discrete and probably not clinically significant. On day 3, all parameters except aPTT in group 1 (not measured in group 2) indicated a continuous coagulation activity. Conclusion. The tendency for coagulation activity altered based on the length and degree of surgery. A continuously altered activity was observed compatible with the reported increased risk of venous thromboembolism at day 3. However, before introducing thromboprophylaxis guidelines larger series of multicentre studies are needed.

Hypercoagulability panel testing predicts thrombosis in neonates undergoing cardiac surgery

Thrombosis contributes to morbidity and mortality in neonates following cardiac surgery. Alterations in hemostatic factors following cardiac surgery have been described, but there is no data correlating these changes with risk of thrombosis in neonates. The aim of this study is to predict thrombosis in neonates undergoing cardiac surgery by assessment of a panel of hypercoagulability markers. Neonates undergoing cardiac surgery were enrolled preoperatively and prospectively followed. Preoperative hypercoagulability panel testing included thrombin generation assay (TGA), immunoassays for antithrombin III, protein C, protein S, factor VIII, thrombin-activatable fibrinolytic inhibitor (TAFI), plasminogen activator inhibitor-1 (PAI-1), and cardiolipin antibody. Postoperative thrombosis was defined by clinical events (shunt thrombosis, limb ischemia, and stroke) or imaging (intravascular or intracardiac thrombus). Risk factors for thrombosis were assessed. One hundred neonates were enrolled in the study over a two-year period. The incidence of postoperative in-hospital thrombosis was 20%. The only significant clinical risk factor associated with thrombosis was the single ventricle physiology. Hypercoagulability factors associated with increased risk of thrombosis by univariate analysis were elevated PAI-1, TAFI, and TGA, and presence of anticardiolipin antibodies. Multivariable logistic regression analysis demonstrated that elevated PAI-1 (P = 0.015), TAFI (P = 0.028), and TGA (P = 0.007) were independent predictors of thrombosis. Hypercoagulability panel testing may help identify neonates at high risk for thrombosis following cardiac surgery. Future studies are warranted to determine if high risk patients benefit from targeted anticoagulation therapies.

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

BACKGROUND

Discussion at local meetings led to the realization of the diversity in anaesthetic practice for pediatric and adolescent scoliosis surgery. This diversity was assessed using an online survey, the aim being to provoke discussion and highlight areas of future research.

METHODS

Of the 24 centers practicing pediatric and adolescent scoliosis surgery, 21 completed questionnaires, a response rate of 88%.

RESULTS

Blood conservation; the area of greatest clinical variability was seen in dosing regimes for Tranexamic acid. Thromboprophylaxis; both mechanical and pharmacological regimes showed wide range in both application and timing. Pain control; eight different types of postoperative pain relief were utilized across the centres, some in isolation but many in combination.

CONCLUSIONS

The results from our survey show wide variation nationally and hopefully will provoke discussion and ultimately national multi-centred research to define best practice.