The safety of continuous fascia iliaca block in patients with hip fracture taking pre-injury anticoagulant and/or antiplatelet medications.

BACKGROUND: Fascia iliaca compartment block (FICB) is an effective method to treat pain in adult trauma patients with hip fracture. Of importance is the high prevalence of preinjury anticoagulants and antiplatelet medications in this population. To date, we have not identified any literature that has specifically evaluated the safety of FICB with continuous catheter infusion in patients on antiplatelet and/or anticoagulant therapy. The purpose of this study is to quantify the complication rate associated with FICB in patients who are actively taking prescribed anticoagulant and/or antiplatelet medications prior to injury and identify factors that may predispose patients to an adverse event. METHODS: This retrospective study included consecutive adult trauma patients (age ≥18) with hip fracture who underwent placement of FICB within 24 h of admission and had been taking anticoagulant and/or antiplatelet medications pre-injury. Patients were excluded if their catheter was placed more than 24 h post-hospital admission. Patients were evaluated for demographics, injury severity, laboratory values, medication history, receipt of coagulation-related reversal medications, and complications related to FICB placement. Complications included bleeding at the insertion site requiring catheter removal and 30-day catheter site infection. The incidence of complications was reported and risk factors for complications were identified using univariate and multivariate statistics. RESULTS: There were 124 patients included. The mean age was 81 ± 10 years, and the most common mechanism was ground level fall (94%). Most patients were taking single antiplatelet therapy (65%), followed by anticoagulant alone (21%), combined antiplatelet and anticoagulant therapy (7.3%) and dual antiplatelet therapy (7.3%). The most common antiplatelet was aspirin (88%) and the most common anticoagulant was warfarin (60%). Of the patients taking warfarin, the average INR on admission was 2.3 ± 0.8. Only 1 bleeding complication (0.8%) was noted in a patient prescribed clopidogrel pre-injury which occurred 5 days post-catheter placement. This same patient was noted to have superficial surgical site bleeding most likely secondary to the use of enoxaparin for post-operative deep venous thrombosis prophylaxis. There were 4 orthopedic superficial surgical site infections (3.2%), all remote from the catheter site. The pre-injury medication prescribed in these patients was aspirin 81 mg, aspirin 325 mg, rivaroxaban and dabigatran, respectively. No factors were associated with a complication thus multivariate analysis was not performed. CONCLUSION: The incidence of complications associated with fascia iliaca compartment block (FICB) in adult trauma patients prescribed pre-injury anticoagulants or antiplatelet medications is low. In this retrospective review, we did not identify any complications that were directly associated with the FICB procedure. Fascia iliaca block with continuous infusion catheter placement can be safely performed on patients who are on therapeutic anticoagulant and/or antiplatelet agents.

Geriatric trauma hip fractures: is there a difference in outcomes based on fracture patterns?

BACKGROUND: Annually in the US, there are over 300,000 hospital admissions due to hip fractures in geriatric patients. Consequently, there have been several large observational studies, which continue to provide new insights into differences in outcomes among hip fracture patients. However, few hip fracture studies have specifically examined the relationship between hip fracture patterns, sex, and short-term outcomes including hospital length of stay and discharge disposition in geriatric trauma patients. METHODS: We performed a retrospective study of hip fractures in geriatric trauma patients. Hip fracture patterns were based on ICD -9 CM diagnostic codes for hip fractures (820.00-820.9). Patient variables were patient demographics, mechanism of injury, injury severity score, hospital and ICU length of stay, co-morbidities, injury location, discharge disposition, and in-patient mortality. RESULTS: A total of 325 patient records met the inclusion criteria. The mean age of the patients was 82.2 years, and the majority of the patients were white (94%) and female (70%). Hip fractures patterns were categorized as two fracture classes and three fracture types. We observed a difference in the proportion of males to females within each fracture class (Femoral neck fractures Z-score = -8.86, p < 0.001, trochanteric fractures Z-score = -5.63, p < 0.001). Hip fractures were fixed based on fracture pattern and patient characteristics. Hip fracture class or fracture type did not predict short-term outcomes such as in-hospital or ICU length of stay, death, or patient discharge disposition. The majority of patients (73%) were injured at home. However, 84% of the patients were discharged to skilled nursing facility, rehabilitation, or long-term care while only 16% were discharged home. There was no evidence of significant association between fracture pattern, injury severity score, diabetes mellitus, hypertension or dementia. CONCLUSIONS: Hip fracture patterns differ between geriatric male and female trauma patients. However, there was no significant association between fracture patterns and short-term patient outcomes. Further studies are planned to investigate the effect of fracture pattern and long-term outcomes including 90-day mortality, return to previous levels of activity, and other quality of life measures.

Effect of fatigue loading and associated matrix microdamage on bone blood flow and interstitial fluid flow.

Functional adaptation of bone to cyclic fatigue involves a complex physiological response that is targeted to sites of microdamage. The mechanisms that regulate this process are not understood, although lacunocanalicular interstitial fluid flow is likely important. We investigated the effect of a single period of cyclic fatigue on bone blood flow and interstitial fluid flow. The ulnae of 69 rats were subjected to cyclic fatigue unilaterally using an initial peak strain of -6000 muepsilon until 40% loss of stiffness developed. Groups of rats (n=23 per group) were euthanized immediately after loading, at 5 days, and at 14 days. The contralateral ulna served as a treatment control, and a baseline control group (n=23) that was not loaded was also included. After euthanasia, localization of intravascular gold microspheres within the ulna (n=7 rats/group) and tissue distribution of procion red tracer were quantified (n=8 rats/group). Microcracking, modeling, and remodeling (Cr.S.Dn, microm/mm(2), Ne.Wo.B.T.Ar, mm(2), and Rs.N/T.Ar, #/mm(2) respectively) were also quantified histologically (n=8 rats/group). Cyclic fatigue loading induced hyperemia of the loaded ulna, which peaked at 5 days after loading. There was an associated overall decrease in procion tracer uptake in both the loaded and contralateral control ulnae. Tracer uptake was also decreased in the periosteal region, when compared with the endosteal region of the cortex. Pooling of tracer was seen in microdamaged bone typically adjacent to an intracortical stress fracture at all time points after fatigue loading; in adjacent bone tracer uptake was decreased. New bone formation was similar at 5 days and at 14 days, whereas formation of resorption spaces was increased at 14 days. These data suggest that a short period of cyclic fatigue induces bone hyperemia and associated decreased lacunocanalicular interstitial fluid flow, which persists over the time period in which osteoclasts are recruited to sites of microdamage for targeted remodeling. Matrix damage and development of stress fracture also interfere with normal centrifugal fluid flow through the cortex. Changes in interstitial fluid flow in the contralateral ulna suggest that functional adaptation to unilateral fatigue loading may include a more generalized neurovascular response.