Administration off label of recombinant factor-VIIa (rFVIIa) to patients with blunt or penetrating brain injury without coagulopathy

Trauma-induced coagulopathy: from biology to therapy

Trauma is a leading cause of death and disability. Hemorrhage is the major mechanism responsible for death during the first 24 hours following trauma. One quarter of severely injured patients present in the emergency room with acute coagulopathy of trauma and shock (ACOT). The drivers of ACOT are tissue hypoperfusion, inflammation, and activation of the neurohumoral system. ACOT is a result of protein C activation with cleavage of activated factor VIII and V and inhibition of plasminogen activator inhibitor-1 (PAI-1). The resuscitation-associated coagulopathy (RAC) is secondary to a combination of acidosis, hypothermia and dilution from intravenous blood and fluid therapy. RAC may further aggravate acidosis and hypoxia resulting in a vicious cycle. This review focuses on the biology of the trauma-associated coagulopathy, and reviews current therapeutic strategies.

Hemorrhagic progression of a contusion after traumatic brain injury: a review

The magnitude of damage to cerebral tissues following head trauma is determined by the primary injury, caused by the kinetic energy delivered at the time of impact, plus numerous secondary injury responses that almost inevitably worsen the primary injury. When head trauma results in a cerebral contusion, the hemorrhagic lesion often progresses during the first several hours after impact, either expanding or developing new, non-contiguous hemorrhagic lesions, a phenomenon termed hemorrhagic progression of a contusion (HPC). Because a hemorrhagic contusion marks tissues with essentially total unrecoverable loss of function, and because blood is one of the most toxic substances to which the brain can be exposed, HPC is one of the most severe types of secondary injury encountered following traumatic brain injury (TBI). Historically, HPC has been attributed to continued bleeding of microvessels fractured at the time of primary injury. This concept has given rise to the notion that continued bleeding might be due to overt or latent coagulopathy, prompting attempts to normalize coagulation with agents such as recombinant factor VIIa. Recently, a novel mechanism was postulated to account for HPC that involves delayed, progressive microvascular failure initiated by the impact. Here we review the topic of HPC, we examine data relevant to the concept of a coagulopathy, and we detail emerging data elucidating the mechanism of progressive microvascular failure that predisposes to HPC after head trauma.

Practical aspects of the oral new anticoagulants

After years of only oral vitamin K antagonists, there are new many new antithrombotic agents in development and on entering the marketplace. This review will analyze clinical trial results for these new agents-especially dibigatran, rivaroxaban, and apixiban. Also to be discussed are practical aspects of use of these new agents such monitoring, reversal, and use before procedures.

The effect of rFVIIa on pro- and anti-inflammatory cytokines in serum and cerebrospinal fluid in a swine model of traumatic brain injury

Traumatic brain injury (TBI) is associated with significant infectious and inflammatory complications. Though increasing evidence suggests that rFVIIa administration may be efficacious for the pre-hospital treatment of TBI, the FVIIa-tissue factor complex has been shown to be immunologically active. To date the cytokine response to rFVIIa administration for the treatment of TBI has not been evaluated. Twenty anesthetized immature Yorkshire swine underwent fluid percussion TBI. At 15 min following injury, animals were randomized to receive either 90 μg/kg rFVIIa (rFVIIa) or nothing. Animals were observed for 6 h and then euthanized. Plasma and cerebrospinal (CSF) samples were collected at 0 min and 360 min, and ELISA analysis of TNF-α, IL-1β and IL-10 was performed. Survival in both groups was 100%. Baseline cytokine concentrations were not statistically different between rFVIIa and control animals in plasma or CSF. Animals in both groups did not have significant changes in plasma cytokine concentrations following TBI. Control animals did not demonstrate significant changes from baseline of CSF cytokine concentrations following TBI. The administration of rFVIIa however, resulted in significant increases in CSF TNF-α concentration (232.0 pg/ml ± 75.9 vs 36.4 pg/ml ± 10.4, p = 0.036) and IL-10 concentration (10.7 pg/ml ± 0.6 vs 8.8 pg/ml ± 0.1, p = 0.015). IL-1β concentrations were not significantly changed over the experimental time course. These results suggest that rFVIIa administration for the treatment of TBI is not immunologically inert, and is associated with increased CSF concentrations of TNF-α and IL-10.

Correction of coagulation in dilutional coagulopathy: use of kinetic and capacitive coagulation assays to improve hemostasis

The management of dilutional coagulopathy due to fluid infusion and massive blood loss is a topic that deserves a biochemical approach. In this review article, we provide an overview of current guidelines and recommendations on diagnosis and on management of transfusion in acquired coagulopathy. We discuss the biochemical differences between kinetic clotting assays (clotting times) and new capacitive coagulation measurements that provide time-dependent information on thrombin generation and fibrin clot formation. The available evidence suggests that a combination of assay types is required for evaluating new transfusion protocols aimed to optimize hemostasis and stop bleeding. Although there is current consensus on the application of fresh frozen plasma to revert coagulopathy, factor concentrates may appear to be useful in the future.

D-dimer as a predictor of progressive hemorrhagic injury in patients with traumatic brain injury: analysis of 194 cases

This study sought to describe and evaluate any relationship between D-dimer values and progressive hemorrhagic injury (PHI) after traumatic brain injury (TBI). In patients with TBI, plasma D-dimer was measured while a computed tomography (CT) scan was conducted as soon as the patient was admitted to the emergency department. A series of other clinical and laboratory parameters were also measured and recorded. A logistic multiple regression analysis was used to identify risk factors for PHI. A cohort of 194 patients with TBI was evaluated in this clinical study. Eighty-one (41.8%) patients suffered PHI as determined by a second CT scan. The plasma D-dimer level was higher in patients who demonstrated PHI compared with those who did not (P < 0.001. Using a receiver-operator characteristic curve to predict the possibility by measuring the D-dimer level, a value of 5.00 mg/L was considered the cutoff point, with a sensitivity of 72.8% and a specificity of 78.8%. Eight-four patients had D-dimer levels higher than the cut point value (5.0 mg/L); PHI was seen in 71.4% of these patients and in 19.1% of the other patients (P < 0.01). Factors with P < 0.2 on bivariate analysis were included in a stepwise logistic regression analysis to identify independent risk factors for TBI coagulopathy. Logistic regression analysis showed that the D-dimer value was a predictor of PHI, and the odds ratio (OR) was 1.341 with per milligram per liter (P = 0.020). The stepwise logistic regression also identified that time from injury to the first CT shorter than 2 h (OR = 2.118, P = 0.047), PLT counts lesser than 100 x 109/L (OR = 7.853, P = 0.018), and Fg lower than 2.0 g/L (OR = 3.001, P = 0.012) were risk factors for the development of PHI. When D-dimer values were dichotomized at 5 mg/L, time from injury to the first CT scan was no longer a risk factor statistically while the OR value of D-dimer to the occurrence of PHI elevated to 11.850(P < 0.001). The level of plasma D-dimer after TBI can be a useful prognostic factor for PHI and should be considered in the clinical management of patients in combination with neuroimaging and other data.

The role of recombinant-activated factor VII in bleeding trauma patients

PURPOSE OF REVIEW

Exsanguinating hemorrhage and postshock organ failure account for 35-40% of deaths from trauma, and there is an increasing recognition of the importance of coagulopathy in the evolution of this disease.

RECENT FINDINGS

Since 1999, case reports, small series, retrospective studies and a few controlled trials have reported the use of recombinant-activated factor VII (rFVIIa) as an adjunct for reversal of coagulopathy in trauma patients, and numerous other publications have examined the use of rFVIIa in related conditions such as traumatic brain injury, hemorrhagic stroke and uncontrolled surgical bleeding.

SUMMARY

We present a brief discussion of the mechanism of action of rFVIIa and its role in facilitating hemostasis and a review of the recent medical literature on the use of rFVIIa in trauma patients, including current guidelines and controversies.

Disseminated intravascular coagulation after isolated mild head injury

A rare case is described of acute disseminated intravascular coagulation (DIC) following isolated mild head injury with acute subdural haematoma, coagulopathy onset preceding craniotomy. Surgical treatment of the cause followed by swift diagnosis and treatment soon after surgery enabled a good outcome. Post-operative recollection of subdural and extadural blood was treated by further surgery. DIC following isolated mild head injury without axonal damage is rare, but fatal if missed. Thrombocytopaenia in head injured patients should be investigated expediently. Post-operative interim imaging (if not standard practice) should also be considered to exclude haemorrhagic recollection requiring further surgery.

Reversal of coagulopathy in critically ill patients with traumatic brain injury: recombinant factor VIIa is more cost-effective than plasma

BACKGROUND

Traumatic brain injury (TBI) is the leading cause of death and disability after trauma. Coagulopathy is common in this patient population and requires rapid reversal to allow for safe neurosurgical intervention and prevent worsening of the primary injury. Typically reversal of coagulopathy is accomplished with the use of plasma. Recombinant factor VIIa (rFVIIa; NovoSeven, Novo Nordisk, Bagsvaerd, Denmark) has become increasingly used "off-label" in patients with neurosurgical emergencies to rapidly reverse coagulopathy. We hypothesized that the use of rFVIIa in this patient population would prove to be cost-effective as well as demonstrate clinical benefit.

METHODS

The trauma registry at the R Adams Cowley Shock Trauma Center was used to identify all coagulopatic trauma patients admitted between January 2002 and December 2007 with relatively isolated TBI (head Abbreviated Injury Scale score of >or=4). The medical records of patients were reviewed and demographics, injury-specific data, medications administered, laboratory values, blood product utilization, neurosurgical procedures, length of stay (LOS), discharge disposition, and outcome data were abstracted. Patients who received rFVIIa for reversal of coagulopathy were compared against those who did not receive rFVIIa. t Tests were used to compare differences between continuous variables, and chi2 analysis was used to compare categorical variables. A p value of <0.05 was considered significant for all statistical tests.

RESULTS

During a 6-year period, there were 179 patients who met inclusion criteria. One hundred eleven patients (62.0%) were treated with conventional therapy alone whereas 68 (38.0%) received rFVIIa. Baseline characteristics between the two groups were similar except that Injury Severity Score and admission International normalized ratio were higher in the rFVIIa group and the rFVIIa group had a higher percentage of patients with head Abbreviated Injury Scale score of 5 injuries, patients who underwent neurosurgical procedures and patients with preinjury warfarin use. There was no difference in total charges between these groups (mean US $63,403 in the conventionally treated group vs. $66,086). When patients who required admission to the intensive care unit were analyzed (n = 110, 50% received rFVIIa), total mean charges and costs were significantly lower in the group that received rFVIIa (mean US $108,900 vs. $77,907). Hospital LOS, days of mechanical ventilation, and plasma utilization were lower in the rFVIIa group. Mortality and thromboembolic complication rates were not different between the two groups.

CONCLUSION

In this study, we were able to demonstrate a significant economic benefit of the use of rFVIIa for reversal of coagulopathy in severely injured patients with TBI. Not all patients with coagulopathy and an anatomic brain injury benefit, but in patients who are neurologically or physiologically compromised, using rFVIIa decreases total charges and costs of hospitalization. This decrease in overall cost is directly attributable to the significant decrease in LOS and decrease in the need for mechanical ventilation. This study demonstrates that in coagulopathic patients with TBI who require intensive care unit admission, rFVIIa is cost-effective and safe. Prospective studies are needed to confirm these findings and establish clinical effectiveness.