Anticoagulation therapy and proximal femoral fracture treatment: An update

Aspirin in prevention of venous thromboembolism following hip fracture surgery: A systematic review and meta-analysis

Background

Many orthopaedic surgeons routinely prescribe aspirin (ASA) as prophylaxis for venous thromboembolism (VTE) following hip fracture surgery (HFS). The purpose of this study is to assess the effectiveness of aspirin to other agents in preventing VTE and mortality following hip fracture surgery.

Methods

Following PRISMA guidelines, we performed a search for HFS studies from 1998 to 2023 reporting comparisons between aspirin and other chemoprophylaxis methods for VTE (DVT - deep vein thrombosis; PE - pulmonary embolism). SPSS Meta-analysis function was used to calculate Mean Effect Size Estimate (MESE) and 95 % Confidence Intervals for each outcome. Reverse Fragility Index (RFI) and Fragility Quotient (FQ) were calculated for each study.

Results

Of the 847 articles screened, 4 studies with 5 comparisons met the search criteria to be included for analysis. A total of 1194 participants were included in these studies. There was a decreased risk of mortality seen with use of aspirin compared to other agents (MESE = 0.86, 95 % CI: [0.07-1.66]; p=.03). There was no increased risk of DVT or PE with use of aspirin (both p>.4). The overall RFI and FQ for all 19 outcomes were 12 (IQR: 6.5-15) and 0.080 (IQR: 0.027-0.110), respectively. Ten studies (52.6 %) reported a loss-to-follow-up (LTF) greater than the overall RFI.

Conclusions

Aspirin demonstrates similar protective effects on prevention of VTE compared to other agents and may have significant protective effects on overall mortality following surgical intervention for hip fractures. However, the current evidence concerning its use in this arena is less than robust, with more than half of the studied outcomes considered statistically fragile.

Aspirin prophylaxis is not associated with increased risk of venous thromboembolism in arthroplasty for femoral neck fractures: a non-inferiority study

PURPOSE

Venous thromboembolism (VTE) is a known complication of hip arthroplasty for femoral neck fractures (FNF) with various prophylactic anticoagulants utilized to decrease risk. The purpose of this study was to assess the efficacy and perioperative outcomes associated with aspirin for VTE prophylaxis following arthroplasty for FNF.

METHODS

Medical records of 1,220 patients who underwent hip hemiarthroplasty (HHA) or total hip arthroplasty (THA) at an urban academic center from 2011 to 2022 were retrospectively reviewed. Patient characteristics and perioperative outcomes, including length of stay (LOS), VTE, 90-day hospital encounters, and discharge disposition, were collected. Outcomes for patients prescribed aspirin (n = 214) were compared to those prescribed non-aspirin VTE prophylaxis (n = 1006) using propensity score matching.

RESULTS

Patients who received aspirin had higher rates of THA (36.0 vs 26.7%; p = 0.008). There were no significant risk-adjusted differences in the incidence of VTE (0.5 vs 0.5%, p = 1.000) and 90-day readmissions (10.4 vs 12.3%, p = 0.646) between patients prescribed aspirin and non-aspirin VTE prophylaxis, respectively. Patients prescribed non-aspirin agents had higher rates of non-home discharge (73.9 vs 58.5%; p < 0.001) and longer LOS (143.5 vs 124.9 h; p = 0.005). Sub-analysis of patients prescribed aspirin and non-aspirin prophylaxis based on comorbidity scores demonstrated no difference in VTE incidence for low (0.0 vs 1.6%, p = 1.000) and high scores (0.0 vs 0.0%, p = 1.000), respectively.

CONCLUSION

Aspirin is not associated with increased incidence of VTE after HHA or THA for FNF. Aspirin prophylaxis should be considered in hip fracture patients to mitigate bleeding risk, particularly those with low to intermediate VTE risk.

LEVEL OF EVIDENCE

Level III, Retrospective study.

Suboptimal Use of DOACs Post-Discharge for Geriatric Hip Fractures with Isolated Calf Deep Vein Thrombosis: Do Clinician Prescribing Preferences and Patient Compliance Alters Clinical Outcomes?

Introduction

This study aimed to examine the impacts of DOACs compliance and prescribing preferences on clinical outcomes in elderly hip fracture patients with isolated calf deep vein thrombosis (ICDVT).

Methods

We conducted a retrospective cohort study that evaluated 702 patients who underwent surgical treatment combined with ICDVT in an academic university hospital between January 2016 and October 2021. DOACs compliance was investigated through telephone and outpatient follow-up, and ICDVT clinical outcomes were collected 30 and 90 days post-discharge, respectively. Variables of interest were collected through the electronic medical record system, and data were analyzed after adjusting for predictors of non-completely dissolved (CD) of ICDVT.

Results

The DOACs compliance survey revealed that 375 (53.42%) patients were fully adherent, 270 (38.46%) were fairly adherent, and 57 (8.12%) were poorly adherent. Approximately 62% of patients had ICDVT dissipation within 30 days after discharge, reaching 94% within 90 days. DOACs QD/BID regimen is often based on economic status, activity capacity, discharge destination and post-operative weight-bearing activities (p<0.05).The mechanism of injury, ASA classification, surgical technique and timing of ICDVT formation were significantly correlated with DOACs 14/28 days regimen (p<0.05).Multivariate analysis revealed that rural patients [OR 1.518 (95% CI, 1.117-2.236)], pre-operative ICDVT[OR 2.816 (95% CI, 1.862-4.259)] and thrombus length [OR 1.157 (95% CI, 1.263-1.821)] were ICDVT risk factors for non-CD. Furthermore, DOACs fair compliance [OR 0.087 (95% CI, 0.042-0.178)], DOACs full compliance [OR 0.283 (95% CI, 0.139-0.579)], and hospitalization duration [OR 0.793 (95% CI, 0.694-0.907)] were ICDVT protective factors for CD.

Conclusion

Better compliance with DOACs benefits early ICDVT dissipation, but final clinical outcomes have to be validated with longer follow-up periods. When managing elderly patients with hip fractures, indications for anticoagulation should be considered and individualized protocols should be used.

Effect and safety of topical application of tranexamic acid to reduce perioperative blood loss in elderly patients with intertrochanteric fracture undergoing PFNA

The specific method and dose of tranexamic acid (TXA) topically applied for intertrochanteric fractures have not been well established. The aim of this study is to investigate the efficacy and safety of TXA topically administered via our protocol for perioperative bleeding management in elderly patients with intertrochanteric fractures who underwent proximal femoral nail anti-rotation (PFNA).A retrospective comparative analysis was performed. The TXA group was composed of 82 patients with topical use of TXA, and the control group was composed of 82 patients without TXA use during the PFNA procedure. Intraoperative, total and hidden amounts of blood loss, drainage volumes, postoperative blood transfusion volumes and complications were compared between the 2 groups.The intraoperative, total and hidden amounts of blood loss and the drainage volumes were significantly lower in the TXA group than in the control group (P = .012, P < .01, P < .01, P = .014, respectively). The volume and rate of blood transfusion in the TXA group were significantly lower than those in the control group (P < .01). There were no significant differences in complications between the 2 groups (P > .05).Topical application of TXA offers an effective and safe option for reducing perioperative blood loss and transfusion in elderly patients with intertrochanteric fractures undergoing PFNA.

Direct oral anticoagulants (DOACs) and neck of femur fractures: Standardising the perioperative management and time to surgery

Demographic projections for hip fragility fractures indicate a rising annual incidence by virtue of a multimorbid, ageing population with more noncommunicable diseases (NCDs). NCDs are characterised by slow progression and long duration ranging from ischaemic cardiovascular disease, cerebrovascular disease, diabetes, chronic obstructive pulmonary disease to various cancers. Management of this disease burden often involves commencing patients on oral anticoagulants to reduce the risk of thromboembolic events. The use of direct oral anticoagulants (DOACs) in clinical practice has increased due to their rapid onset of action, short half-life and predictable anticoagulant effects, without the need for routine monitoring. Safe and timely surgical intervention relies on reversal of anticoagulants. However, the lack of specific evidence-based guidelines for the perioperative management of patients on DOACs with hip fractures has proved challenging; in particular, the accessibility of DOAC-specific assays, justification of the cost-benefit ratio of targeted reversal agents and indications for neuraxial anaesthesia. This has led to potentially avoidable delays in surgical intervention. Following a literature review of the pharmacokinetic and pharmacodynamics of commonly used DOACs in our region including the role of surrogate markers, we propose a systematic, evidence-based guideline to the perioperative management of hip fractures DOACs. We believe this standardised protocol can be easily replicated between hospitals. We recommend that if patients are deemed suitable for a general anaesthesia, with satisfactory renal function, optimal surgical time should be 24 h following the last ingested dose of DOAC.

Higher coagulation activity in hip fracture patients: A case-control study using rotational thromboelastometry

INTRODUCTION

Trauma-induced coagulopathy has been extensively investigated in the multitrauma setting, but only sparsely following moderate orthopedic trauma. The purpose of this study was to evaluate changes in the hemostatic profile of patients with hip fractures, using rotational thromboelastometry (ROTEM).

METHODS

198 patients with hip fractures who underwent surgery were included in the study. A matched group of 52 healthy individuals was also enrolled. Demographics, conventional laboratory assays, and ROTEM parameters were recorded and compared between patients and healthy adults. The preoperative and postoperative ROTEM values of fractured patients were also compared.

RESULTS

The conventional coagulation assays were similar for the 2 groups. However, several ROTEM parameters including EXTEM MCF (P < .001), EXTEM alpha angle (P < .001), INTEM MCF (P < .001), INTEM A10 (P < .001), and INTEM alpha angle (P < .001) significantly differed between the 2 groups indicating a higher coagulation potential following hip fractures. Also, fractured patients had significantly lower INTEM and EXTEM CT values (P = .008 and P = .012, respectively) and significantly lower INTEM and EXTEM CFT values (P < .001). Adjusted analysis for confounders further confirmed the direct relationship between hip fracture and higher coagulation activity. Last, INTEM CT and CFT significantly decreased (P = .008 and P < .001, respectively), while INTEM MCF, A10, and alpha angle significantly increased (P < .001) postoperatively, indicating that surgery further increases the coagulation potential.

CONCLUSION

A higher coagulation activity following hip fractures and surgical treatment can be detected by ROTEM shortly after the injury, even when this is undetectable by conventional coagulation assays.

Association of Reversal of Anticoagulation Preoperatively on 30-Day Mortality and Outcomes for Hip Fracture Surgery

BACKGROUND

Hip fracture is common in the elderly, many of whom are on anticoagulation. However, data are limited on outcomes with anticoagulation reversal in patients undergoing hip fracture surgery.

METHODS

Adults ≥60 years old on oral anticoagulation who underwent hip fracture surgery at 21 hospitals in Northern California from 2006 to 2016 were identified through electronic databases. Outcomes were compared among patients treated and untreated with anticoagulation reversal preoperatively.

RESULTS

Of 1984 patients on oral anticoagulation who underwent hip fracture surgery, 1943 (97.9%) were on warfarin and 41 (2.1%) were on direct oral anticoagulants. Reversal agents were administered to 1635 (82.4%). Compared to a watch-and-wait strategy, patients receiving reversal agents were more likely to be white, male, comorbid, and with higher admission and preoperative international normalized ratios (P <0.001 for all comparisons). No difference for 30-day mortality was detected between reversal vs non-reversal (7.8% vs 6.0%, respectively; hazard ratio [HR], 1.30 [95% confidence interval (CI), 0.82-2.07]). For secondary outcomes, reversal was associated with higher risk of delirium (8.6% vs 4.9%, risk ratio [RR], 1.77 [95% CI, 1.08-2.89]) and increased mean length of stay (6.4 vs 5.8 days, P <0.05). After adjustment, associations were no longer significant for delirium (RR 1.60, 95% CI, 0.97-2.65) or length of stay (mean difference 0.08, 95% CI, -0.55-0.71). No associations were detected between reversal and other secondary outcomes.

CONCLUSION

No significant associations were found between reversal agents and 30-day mortality or other outcomes in patients on oral anticoagulation who underwent hip fracture surgery. Further investigation is needed.

Serum Concentrations and Elimination Rates of Direct-Acting Oral Anticoagulants (DOACs) in Older Hip Fracture Patients Hospitalized for Surgery: A Pilot Study

BACKGROUND

Use of direct-acting oral anticoagulants (DOACs) is increasing, but knowledge about pharmacokinetics and safety in frail patients is lacking.

OBJECTIVE

The aim was to determine serum concentrations and elimination rates of DOACs in older hip fracture patients hospitalized for surgery.

METHODS

The study included patients ≥ 65 years of age hospitalized for acute hip fracture surgery over a period of 6 months. Use of antithrombotic drugs was registered and serum samples collected for analysis of DOACs (apixaban, dabigatran and rivaroxaban) at admission and surgery. Measured concentrations were assessed in relation to reference (therapeutic) ranges of the respective drugs and applied for half-life calculations. Furthermore, waiting time for surgery was compared between DOAC and warfarin users.

RESULTS

Of 167 patients included (median age 84 years), 11 and 14 used DOACs and warfarin, respectively. Seven of the DOAC-treated patients had concentrations above the upper reference range (> 300 nM) at admission, and concentrations were still in the reference range for five of these at surgery. Elimination half-lives could be estimated in eight patients and ranged between 14.6 and 59.7 h (median 21.6). The observed waiting time for surgery was longer for patients using DOACs than warfarin (median 44 vs. 25 h).

CONCLUSION

This pilot study indicates that older patients prone to hip fracture are at risk of being exposed to therapeutic serum concentrations of DOACs during surgery due to reduced drug elimination rates. The observation that almost 50% of the patients had therapeutic concentrations at surgery should be investigated further regarding safety of DOAC use in this frail elderly population.

Thromboembolism prophylaxis in orthopaedics: an update

Venous thromboembolism (VTE) is a serious complication during and after hospitalization, yet is a preventable cause of in-hospital death.

Without VTE prophylaxis, the overall VTE incidence in medical and general surgery hospitalized patients is in the range of 10% to 40%, while it ranges up to 40% to 60% in major orthopaedic surgery. With routine VTE prophylaxis, fatal pulmonary embolism is uncommon in orthopaedic patients and the rates of symptomatic VTE within three months are in the range of 1.3% to 10%.

VTE prophylaxis methods are divided into mechanical and pharmacological. The former include mobilization, graduated compression stockings, intermittent pneumatic compression device and venous foot pumps; the latter include aspirin, unfractionated heparin, low molecular weight heparin (LMWH), adjusted dose vitamin K antagonists, synthetic pentasaccharid factor Xa inhibitor (fondaparinux) and newer oral anticoagulants. LMWH seems to be more efficient overall compared with the other available agents. We remain sceptical about the use of aspirin as a sole method of prophylaxis in total hip and knee replacement and hip fracture surgery, while controversy still exists regarding the use of VTE prophylaxis in knee arthroscopy, lower leg injuries and upper extremity surgery.

Cite this article: EFORT Open Rev 2018;3:136-148. DOI: 10.1302/2058-5241.3.170018