Comparison of different warfarin reversal protocols on surgical delay and complication rate in hip fracture patients

Propensity matched analysis examining the effect of passive reversal of direct oral anticoagulants on blood loss and the need for transfusions among traumatic geriatric hip fractures

BACKGROUND

Reversal of direct oral anticoagulants (DOACs) is currently recommended prior to emergent surgery, such as surgical intervention for traumatic geriatric hip fractures. However, reversal methods are expensive and timely, often delaying surgical intervention, which is a predictor of outcomes. The study objective was to examine the effect of DOAC reversal on blood loss and transfusions among geriatric patients with hip fractures.

METHODS

This retrospective propensity-matched study across six level I trauma centers included geriatric patients on DOACs with isolated fragility hip fractures requiring surgical intervention (2014-2017). Outcomes included: intraoperative blood loss, intraoperative pRBCs, and hospital length of stay (HLOS).

RESULTS

After matching there were 62 patients (31 reversed, 31 not reversed), 29 patients were not matched. The only reversal method utilized was passive reversal (waiting ≥ 24 hours for elimination). Passively reversed patients had a longer time to surgery (mean, 43 vs. 18 hours, p < 0.01). Most patients (92%) had blood loss (90% passively reversed, 94% not reversed); the median volume of blood loss was 100 mL for both those groups, p = 0.97. Thirteen percent had pRBCs transfused (13% passively reversed and 13% not reversed); the median volume of pRBCs transfused was 525 mL for those passively reversed and 314 mL for those not reversed, p = 0.52. The mean HLOS was significantly longer for those passively reversed (7 vs. 5 days, p = 0.001).

CONCLUSIONS

Passive DOAC reversal for geriatric patients with isolated hip fracture requiring surgery may be contributing to delayed surgery and an increased HLOS without having a significant effect on blood loss or transfusions. These data suggest that passive DOAC reversal may not be necessary prior to surgical repair of isolated hip fracture.

Safety and efficacy of a strategy of vitamin K antagonist reversal with prothrombin complex concentrates compared to vitamin K in patients with hip fracture

Background:

Increased preoperative delay in patients with hip fractures may be responsible for increased morbidity and mortality. We hypothesized that a strategy of reversal of vitamin K antagonist (VKA) by prothrombin complexes concentrates (PCCs), as compared to vitamin K, is safe and reduces preoperative delay and hospital length of stay (LOS).

Methods:

In this pilot study, we reviewed the records of patients admitted to a university-affiliated hospital for hip fracture between Jan. 1, 2012, and Dec. 31, 2016, who were taking VKA. Patients were stratified according to reversal strategy (vitamin K v. PCC). Adverse effects, time to surgery, LOS and mortality were collected from the electronic medical record and were compared between the 2 study groups and a control group not treated with VKA.

Results:

A total of 141 patients were included in the study: 65 in the vitamin K group, 26 in the PCC group and 50 in the control group. The median preoperative delay in the PCC group (20 h [interquartile range (IQR)] 13–25 h]) and the control group (20 h [IQR 15–33 h]) was lower than that in the vitamin K group (45 h [IQR 31–52 h]) (p < 0.001). Patients in the PCC group had a shorter median hospital LOS than those in the vitamin K group (6 d [IQR 4–9 d] v. 8 d [IQR 6–11 d], p < 0.05). No difference was observed in the proportion of patients who received a red blood cell transfusion, or had thrombotic or hemorrhagic complications. No difference in mortality at 12 months was observed between the groups.

Conclusion:

In patients with hip fracture, the use of PCCs as compared to vitamin K to reverse the effect of VKA significantly reduced preoperative delay and hospital LOS, and was not associated with an increase in the rates of thrombotic or hemorrhagic complications. Prospective studies involving a greater number of patients are required to confirm these promising results.

Proximal femur fractures in patients taking anticoagulants

Thirty per cent of patients presenting with proximal femoral fractures are receiving anticoagulant treatment for various other medical reasons. This pharmacological effect may necessitate reversal prior to surgical intervention to avoid interference with anaesthesia or excessive peri/post-operative bleeding. Consequently, delay to surgery usually occurs.

Platelet inhibitors (aspirin, clopidogrel) either alone or combined do not need to be discontinued to allow acute hip surgery. Platelet transfusions can be useful but are rarely needed.

Vitamin K antagonists (VKA, e.g. warfarin) should be reversed in a timely fashion and according to established readily accessible departmental protocols. Intravenous vitamin K on admission facilitates reliable reversal, and platelet complex concentrate (PCC) should be reserved for extreme scenarios.

Direct oral anticoagulants (DOAC) must be discontinued prior to hip fracture surgery but the length of time depends on renal function ranging traditionally from two to four days.

Recent evidence suggests that early surgery (within 48 hours) can be safe. No bridging therapy is generally recommended.

There is an urgent need for development of new commonly available antidotes for every DOAC as well as high-level evidence exploring DOAC effects in the acute hip fracture surgical setting.

Cite this article: EFORT Open Rev 2020;5:699-706. DOI: 10.1302/2058-5241.5.190071

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.

Postoperative Complications of Hip Fractures Patients on Chronic Coumadin: A Comparison Based on Operative International Normalized Ratio

In current clinical practice, orthopedic surgeons often delay the surgery intervention on geriatric hip fracture patients to optimize the international normalized ratio (INR), in order to decrease the risk of postoperative hematological complications. However, some evidence suggests that full reversal protocols may not be necessary, especially for patients with prior thromboembolic history. Our study aims to compare the surgical outcomes of patients with normal versus elevated INR values. We conducted a retrospective chart review on 217 patients who underwent surgeries on hip fractures at two academic trauma centers. We found that in our group (n = 124) of patients with an INR value of 1.5–3.0, there was only one reoperation for a hematoma, but there was a trend for more blood transfusions. There was no statistically significant difference in the odds of reoperation or overall complications. Nevertheless, there were significantly more events of postoperative anemia in this high INR patient group.

Standardised Warfarin Reversal Expedites Time to Theatre for Fractured Neck of Femur Surgery and Improves Mortality Rates: A Matched Cohort Study

BACKGROUND

This study aims to evaluate outcomes for warfarinised hip fracture patients and compare them with a matched nonwarfarinised group, before and after the introduction of national hip fracture guidelines in the United Kingdom.

METHODS

A retrospective cohort study of 1743 hip fracture patients was undertaken. All patients admitted taking warfarin were identified. These patients were then matched to nonwarfarinised patients using nearest neighbour propensity score matching, accounting for age, sex, hip fracture type, and Nottingham Hip Fracture Score. A pre-guideline group (no standardised warfarin reversal regimen) and a post-guideline group (standardised regimen) were identified. Outcomes assessed included time to INR less than 1.7, time to theatre, length of stay, and 30-day and 1-year mortality.

RESULTS

Forty-six warfarinised hip fracture patients were admitted in the pre-guideline group (mean age 80.5, F:M 3:1) and 48 in the post-guideline group (mean age 81.2 years, F:M 3:1). Post-guideline patients were reversed to a safe operative INR level within 18 hours of admission, decreasing the time to first dose vitamin K (p<0.001). 70% of warfarinised patients were operated upon within 36 hours, compared to 19.6% with no regimen (p<0.05). After anticoagulation reversal protocol, thirty-day mortality decreased from 15.2% to 8.3% and 1-year mortality from 43.5% to 33% for warfarinised patients, which is comparable to nonwarfarinised matched patients. There was no significant change in the length of stay pre- and post-guideline for both groups of patients.

CONCLUSIONS

Proactive anticoagulant management and expedient surgery reduces morbidity and mortality when managing this surgically challenging subset of hip fracture patients.

Anticoagulation therapy and proximal femoral fracture treatment: An update

Hip fractures in the elderly population have become a 'disease' with increasing incidence.Most of the geriatric patients are affected by a number of comorbidities.Coagulopathies continue to be a special point of interest for the orthopaedic trauma surgeon, with the management of this high-risk group of patients a hot topic of debate among the orthopaedic community.While a universal consensus on how to manage thromboprophylaxis for this special cohort of patients has not been reached, multiple attempts to define a widely accepted protocol have been published. Cite this article: Ktistakis I, Giannoudis V, Giannoudis PV. Anticoagulation therapy and proximal femoral fracture treatment: an update. EFORT Open Rev 2016;1:310-315. DOI: 10.1302/2058-5241.1.160034.

Prothrombin Complex Concentrates: An Alternative to Fresh Frozen Plasma

Insufficiency fractures are a common cause of morbidity among geriatric patients worldwide. Improved outcomes are known to result from decreased delay to definitive operative fixation and mobilization. Use of warfarin is an important potential cause of delay. The ideal mode of warfarin reversal is currently unknown. Prothrombin complex concentrates (PCCs) offer rapid correction with small infusion volume, both of which are important for elderly patients with multiple comorbidities. The authors present 2 cases of insufficiency fractures occurring in geriatric patients receiving warfarin therapy reversed with a 3-factor PCC. Both patients were independent, community ambulators without significant functional disability and returned to their prior level of functioning. There were no significant bleeding or venous thromboembolic complications. To the authors' knowledge, no previous reports have described the use of PCC in geriatric patients with fractures. Nonetheless, its potential is well documented in emergency and trauma surgery literature. The use of PCC could potentially allow surgeons and hospitals to avoid complications related to immobility and the associated costs of treatment, extended hospital stay, and readmission. The authors' limited experience suggests 3-factor PCC preparations may provide adequate correction to allow expeditious surgical treatment. [Orthopedics. 2017; 40(2):e367-e369.].

Budget impact analysis of warfarin reversal therapies among hip fracture patients in Finland

BACKGROUND

Hip fractures require operation within 36-48 h, and they are most common in the elderly. A high International Normalized Ratio should be corrected before surgery. In the current study, we analyzed the budget impact of various warfarin reversal approaches.

METHODS

Four reversal strategies were chosen for the budget impact analysis: the temporary withholding of warfarin, administration of vitamin K, fresh frozen plasma (FFP), and a four-factor prothrombin complex concentrate (PCC).

RESULTS

We estimated that, annually, 410 hip fracture patients potentially require warfarin reversal in Finland. The least costly treatment was vitamin K, which accounted for €289,000 in direct healthcare costs, and the most costly treatment option was warfarin cessation, which accounted for €1,157,000. In the budget impact analysis, vitamin K, PCC and FFP would be cost-saving to healthcare compared with the current treatment mix.

CONCLUSION

The various warfarin reversal strategies have different onset times, which may substantially impact the subsequent healthcare costs.

"Early Trigger" Intravenous Vitamin K: Optimizing Target-Driven Care in Warfarinised Patients With Hip Fracture

Best practice tariff (BPT) was introduced as a financial incentive model to improve compliance with evidence-based care, such as operation for hip fracture within 36 hours of admission. We previously evaluated the impact of warfarin on patients with hip fracture, revealing significant delay to operation and subsequent loss of revenue. As a result of this, an “early trigger” intravenous vitamin K (IVK) pathway was introduced and the service reaudited a year later. The first cycle was a retrospective audit of all cases with hip fracture against BPT standards over a 32-month period. Subsequent protocol change resulted in all warfarinised cases being given 2 mg IVK in the emergency department prior to blood testing. This protocol was reaudited against the same BPT standards 12 months later. An intention-to-treat approach was used, despite breaches of protocol and other reasons for patients not progressing to theater. The data were analyzed with parametric tools to establish true clinical and statistical impact of the introduction of the protocol. In the first cycle, 80 patients were admitted on warfarin with a mean time to theater of 53.71 hours. Of these patients, 79% breached BPT due to anticoagulation. Twelve months following protocol introduction, 42 patients had a mean time to theater of 37.61 hours. Of these patients, 34% breached BPT due to anticoagulation. These data are both clinically and statistically significant (P < .001). No adverse events occurred. We have shown for the first time that “early-trigger” IVK can reduce delay to theater and maximize tariff payments in warfarinised patients with hip fracture. This is in addition to other established benefits associated with early surgery such as decreasing risk of pressure lesions and pneumonia. It affords high-quality patient-centered care while ensuring trauma units achieve maximal financial reimbursement through pay for improved performance and supports a culture of change behavior.

Preoperative warfarin reversal for early hip fracture surgery

PURPOSE

To evaluate our hospital protocol of low-dose vitamin K titration for preoperative warfarin reversal for early hip fracture surgery.

METHODS

Records of 16 men and 33 women aged 63 to 93 (mean, 81) years who were taking warfarin for atrial fibrillation (n=40), venous thromboembolism (n=9), cerebrovascular accident (n=3), and prosthetic heart valve (n=3) and underwent surgery for hip fractures were reviewed. The 3 patients with a prosthetic heart valve were deemed high risk for thromboembolism and the remainder low-risk. The international normalised ratio (INR) of patients was checked on admission and 6 hours after administration of vitamin K; an INR of <1.7 was considered safe for surgery.

RESULTS

No patient developed venous thromboembolism within one year. The 30-day and one-year mortality was 8.2% and 32.6%, respectively. For the 46 low-risk patients, the mean INR on admission was 2.6 (range, 1.1-4.6) and decreased to <1.7 after a mean of 2.2 (range, 0-4) administrations of 2 mg of vitamin K. Their INR was <1.7 within 18 hours (mean, 14 hours). 78% of patients underwent surgery within 36 hours. In the 22% of patients who did not undergo surgery within 36 hours, the delay was due to insufficient operative time or the patient being medically unfit for surgery. The 3 high-risk patients underwent bridging therapy of low-molecular-weight heparin and received no vitamin K; their mean INR on admission was 3.2 (range, 3.1-3.3) and the mean time to surgery was 5.3 (range, 3-8) days. Two low-risk patients and one high-risk patient died within 5 days of surgery.

CONCLUSION

The low-dose intravenous vitamin K protocol is safe and effective in reversing warfarin within 18 hours. Hip fracture surgery within 36 to 48 hours of admission improves morbidity and mortality.

Impact of multidisciplinary hip fracture program on timing of surgery in elderly patients

The effect of patient characteristics and organizational and system factors on time to surgery were studied using Emilia Romagna Region database and hospital survey. The results showed that the implementation of a Hip Fracture Program significantly increased the probability of early surgery while single intervention had only slight effect

INTRODUCTION

The purpose of this study is to evaluate the effect of formal Hip Fracture Program (HFP) on timing of surgery in hip fracture older patients.

METHODS

This is a retrospective cohort study based on Emilia Romagna administrative databases. Data on organizational and system factor were also obtained through a hospital survey. A multilevel logistic regression analysis was carried out to assess the effect of covariates on early surgery, taking into account patient level, hospital level, and trust level variability.

RESULTS

From 1 January to 31 December 2011, 5,520 subjects over 65 years old underwent surgical repair for hip fracture in Emilia Romagna. The mean waiting time to surgery was 3.4 ± 12.3 days, and the overall percentage of patients operated within 2 days was 52.2%. In the adjusted multilevel logistic model, significant risk factors affecting the timing of surgical intervention at patient level were age, comorbidity, day of admission, and antiplatelet or warfarin therapy while no significant single variables were found at hospital level including dedicated operation theater, hospital volume, dedicated orthogeriatric beds, and geriatrician involvement. The most significant variable was the implementation of HFP at trust level that increased three times the probability of early surgery after adjusting for confounding variables (OR 3.216, 95% CI 0.582-6.539).

CONCLUSIONS

Several modifiable organizational factors may affect the proportion of patients with hip fracture undergoing early surgery. This study suggests that the development and the implementation of an evidence-based HFP at trust level are a key point of the strategy of quality of care.

"Tiers of delay": warfarin, hip fractures, and target-driven care

Anticoagulation reversal is a common cause of operative delay. We sought to establish for the first time the impact this has on best practice tariff (BPT) for patients with hip fracture admitted on warfarin. All patients with hip fracture treated operatively over a 32-month period were reviewed. Basic demographics, time to theater, length of stay, and mortality were recorded for all patients. Independent samples t-tests were used to identify statistically significant differences between patients on warfarin and those not taking the drug. A total of 83 patients were admitted anticoagulated with a mean international normalized ratio of 2.65 and a median time to theater of 49.7 hours. Of these patients, 79% breached BPT, incurring significant financial loss. In the control group, 908 patients took a median 24.5 hours, a 28% breach of BPT (P < .01). Length of stay, Nottingham Hip Fracture Score, and predicted 30-day mortality were similar for both the groups. As well as affecting clinical outcome following hip fracture, delay due to anticoagulation causes considerable loss of BPT. Potential loss of revenue due to delays over the study period was £80 000, inspiring the establishment of an "early trigger" anticoagulation protocol. Although it is accepted that there are limitations to this work, it should raise awareness of the real impact of warfarin on patients with hip fracture both in terms of outcome and for the first time, loss of potential revenue.