Daniel K. Nishijima

Immediate and Delayed Traumatic Intracranial Hemorrhage in Patients With Head Trauma and Preinjury Warfarin or Clopidogrel Use

STUDY OBJECTIVE Patients receiving warfarin or clopidogrel are considered at increased risk for traumatic intracranial hemorrhage after blunt head trauma. The prevalence of immediate traumatic intracranial hemorrhage and the cumulative incidence of delayed traumatic intracranial hemorrhage in these patients, however, are unknown. The objective of this study is to address these gaps in knowledge. METHODS A prospective, observational study at 2 trauma centers and 4 community hospitals enrolled emergency department (ED) patients with blunt head trauma and preinjury warfarin or clopidogrel use from April 2009 through January 2011. Patients were followed for 2 weeks. The prevalence of immediate traumatic intracranial hemorrhage and the cumulative incidence of delayed traumatic intracranial hemorrhage were calculated from patients who received initial cranial computed tomography (CT) in the ED. Delayed traumatic intracranial hemorrhage was defined as traumatic intracranial hemorrhage within 2 weeks after an initially normal CT scan result and in the absence of repeated head trauma. RESULTS A total of 1,064 patients were enrolled (768 warfarin patients [72.2%] and 296 clopidogrel patients [27.8%]). There were 364 patients (34.2%) from Level I or II trauma centers and 700 patients (65.8%) from community hospitals. One thousand patients received a cranial CT scan in the ED. Both warfarin and clopidogrel groups had similar demographic and clinical characteristics, although concomitant aspirin use was more prevalent among patients receiving clopidogrel. The prevalence of immediate traumatic intracranial hemorrhage was higher in patients receiving clopidogrel (33/276, 12.0%; 95% confidence interval [CI] 8.4% to 16.4%) than patients receiving warfarin (37/724, 5.1%; 95% CI 3.6% to 7.0%), relative risk 2.31 (95% CI 1.48 to 3.63). Delayed traumatic intracranial hemorrhage was identified in 4 of 687 (0.6%; 95% CI 0.2% to 1.5%) patients receiving warfarin and 0 of 243 (0%; 95% CI 0% to 1.5%) patients receiving clopidogrel. CONCLUSION Although there may be unmeasured confounders that limit intergroup comparison, patients receiving clopidogrel have a significantly higher prevalence of immediate traumatic intracranial hemorrhage compared with patients receiving warfarin. Delayed traumatic intracranial hemorrhage is rare and occurred only in patients receiving warfarin. Discharging patients receiving anticoagulant or antiplatelet medications from the ED after a normal cranial CT scan result is reasonable, but appropriate instructions are required because delayed traumatic intracranial hemorrhage may occur.

Utility of platelet transfusion in adult patients with traumatic intracranial hemorrhage and preinjury antiplatelet use: a systematic review.

BACKGROUND Preinjury use of antiplatelet agents (e.g., clopidogrel and aspirin) is a risk factor for increased morbidity and mortality for patients with traumatic intracranial hemorrhage (tICH). Some investigators have recommended platelet transfusion to reverse the antiplatelet effects in tICH. This evidence-based medicine review examines the evidence regarding the impact of platelet transfusion on emergency department (ED) patients with preinjury antiplatelet use and tICH on patient-oriented outcomes. METHODS The MEDLINE, EMBASE, Cochrane Library, and other databases were searched. Studies were selected for inclusion if they compared platelet transfusion with no-platelet transfusion in the treatment of adult ED patients with preinjury antiplatelet use and tICH and reported rates of mortality, neurocognitive function, or adverse effects. We assessed the quality of the included studies using standard criteria. RESULTS Five retrospective, registry-based studies were identified, which enrolled 635 patients cumulatively. Based on standard criteria, three studies were of low-quality evidence, and two studies were of very low–quality evidence. One study reported higher in-hospital mortality for patients with platelet transfusion (relative risk, 2.42; 95% confidence interval, 1.2–4.9); another showed a lower mortality rate for patients receiving platelet transfusion (relative risk, 0.21; 95% confidence interval, 0.05–0.95). Three studies did not show any statistical difference in comparing mortality rates between the groups. No studies reported intermediate or long-term neurocognitive outcomes or adverse events. CONCLUSION Five retrospective registry studies with suboptimal methodologies provide inadequate evidence to support the routine use of platelet transfusion in adult ED patients with preinjury antiplatelet use and tICH. (J Trauma Acute Care Surg. 2012;72: 1658–1663. Copyright

Does This Adult Patient Have a Blunt Intra-abdominal Injury?

CONTEXT Blunt abdominal trauma often presents a substantial diagnostic challenge. Well-informed clinical examination can identify patients who require further diagnostic evaluation for intra-abdominal injuries after blunt abdominal trauma. OBJECTIVE To systematically assess the precision and accuracy of symptoms, signs, laboratory tests, and bedside imaging studies to identify intra-abdominal injuries in patients with blunt abdominal trauma. DATA SOURCES We conducted a structured search of MEDLINE (1950-January 2012) and EMBASE (1980-January 2012) to identify English-language studies examining the identification of intra-abdominal injuries. A separate, structured search was conducted for studies evaluating bedside ultrasonography. STUDY SELECTION We included studies of diagnostic accuracy for intra-abdominal injury that compared at least 1 finding with a reference standard of abdominal computed tomography, diagnostic peritoneal lavage, laparotomy, autopsy, and/or clinical course for intra-abdominal injury. Twelve studies on clinical findings and 22 studies on bedside ultrasonography met inclusion criteria for data extraction. DATA EXTRACTION Critical appraisal and data extraction were independently performed by 2 authors. DATA SYNTHESIS The prevalence of intra-abdominal injury in adult emergency department patients with blunt abdominal trauma among all evidence level 1 and 2 studies was 13% (95% CI, 10%-17%), with 4.7% (95% CI, 2.5%-8.6%) requiring therapeutic surgery or angiographic embolization of injuries. The presence of a seat belt sign (likelihood ratio [LR] range, 5.6-9.9), rebound tenderness (LR, 6.5; 95% CI, 1.8-24), hypotension (LR, 5.2; 95% CI, 3.5-7.5), abdominal distention (LR, 3.8; 95% CI, 1.9-7.6), or guarding (LR, 3.7; 95% CI, 2.3-5.9) suggest an intra-abdominal injury. The absence of abdominal tenderness to palpation does not rule out an intra-abdominal injury (summary LR, 0.61; 95% CI, 0.46-0.80). The presence of intraperitoneal fluid or organ injury on bedside ultrasound assessment is more accurate than any history and physical examination findings (adjusted summary LR, 30; 95% CI, 20-46); conversely, a normal ultrasound result decreases the chance of injury detection (adjusted summary LR, 0.26; 95% CI, 0.19-0.34). Test results increasing the likelihood of intra-abdominal injury include a base deficit less than -6 mEq/L (LR, 18; 95% CI, 11-30), elevated liver transaminases (LR range, 2.5-5.2), hematuria (LR range, 3.7-4.1), anemia (LR range, 2.2-3.3), and abnormal chest radiograph (LR range, 2.5-3.8). Symptoms and signs may be most useful in combination, particularly in identification of patients who do not need further diagnostic workup. CONCLUSIONS Bedside ultrasonography has the highest accuracy of all individual findings, but a normal result does not rule out an intra-abdominal injury. Combinations of clinical findings may be most useful to determine which patients do not require further evaluation, but the ideal combination of variables for identifying patients without intra-abdominal injury requires further study.

Impact of Transfusion of Fresh‐frozen Plasma and Packed Red Blood Cells in a 1:1 Ratio on Survival of Emergency Department Patients with Severe Trauma

OBJECTIVES Coagulopathy is common after severe trauma and occurs very early after the initial insult. Some investigators have suggested early and aggressive treatment of the trauma-induced coagulopathy by transfusion of fresh-frozen plasma (FFP) and packed red blood cells (PRBC) in a 1:1 ratio. This evidence-based emergency medicine (EBM) review evaluates the evidence regarding the impact of 1:1 ratio of FFP:PRBC transfusion on survival of emergency department (ED) patients with severe trauma. METHODS The MEDLINE, EMBASE, Cochrane Library, and other databases were searched. Studies were selected for inclusion if they included trauma patients who required blood transfusion. The outcome measures of interest included mortality and adverse effects of high FFP:PRBC ratios. For comparison, the patients were classified into high ratio (1:1, defined as a ratio of 1:< or =1.5) and low ratio (1:>1.5) groups. RESULTS The authors did not identify any randomized controlled trials (RCT), but included four observational studies (three retrospective registry and one prospective cohort studies), which enrolled 1,511 patients cumulatively. One study found a statistically significant difference in mortality rate, favoring high FFP:PRBC ratio (relative risk = 0.72, 95% confidence interval [CI] = 0.59 to 0.89), while three studies showed no benefits. One study reported higher rates of sepsis and single/multiorgan failure (MOF), and another study revealed a higher risk of nosocomial infections and acute respiratory distress syndrome (ARDS) in the high FFP:PRBC ratio group. CONCLUSION Three retrospective registry reviews with suboptimal methodologies and one prospective cohort study provide inadequate evidence to support or refute the use of a high FFP:PRBC ratio in patients with severe trauma.

Trauma Registries: History, Logistics, Limitations, and Contributions to Emergency Medicine Research

Trauma registries have been designed to serve a number of purposes, including quality improvement, injury prevention, clinical research, and policy development. Since their inception over 30 years ago, there are increasingly more institutions with trauma registries, many of which submit data to a national trauma registry. The goal of this review is to describe the history, logistics, and characteristics of trauma registries and their contribution to emergency medicine and trauma research. Discussed in this review are the limitations of trauma registries, such as variability in quality and type of the collected data, absence of data pertaining to long-term and functional outcomes, prehospital information, and complications as well as other methodologic obstacles limiting the utility of registry data in clinical and epidemiologic research.

The Efficacy of Factor VIIa in Emergency Department Patients With Warfarin Use and Traumatic Intracranial Hemorrhage

OBJECTIVES The objective was to compare outcomes in emergency department (ED) patients with preinjury warfarin use and traumatic intracranial hemorrhage (tICH) who did and did not receive recombinant activated factor VIIa (rFVIIa) for international normalized ratio (INR) reversal. METHODS This was a retrospective before-and-after study conducted at a Level 1 trauma center, with data from 1999 to 2009. Eligible patients had preinjury warfarin use and tICH on cranial computed tomography (CT) scan. Patients before (standard cohort) and after (rFVIIa cohort) implementation of a protocol for administering 1.2 mg of rFVIIa in the ED were reviewed. Glasgow Coma Scale (GCS) score, Revised Trauma Score (RTS), Injury Severity Score (ISS), INR, and Marshall score were collected. Outcome measures included mortality, thromboembolic complications, and INR normalization. RESULTS Forty patients (median age=80.5 years, interquartile range [IQR]=63.5-85) were included (20 in each cohort). Age, GCS score, ISS, RTS, initial INR, and Marshall score were similar (p>0.05) between the two cohorts. Survival was identical between cohorts (13 of 20, or 65.0%, 95% confidence interval [CI]=40.8% to 84.6%). There were no differences in rate of thromboembolic complications in the standard cohort (1 of 20, 5.0%, 95% CI=0.1% to 24.9%) than the rFVIIa cohort (4 of 20, 20.0%, 95% CI=5.7% to 43.7%; p=0.34). Time to normal INR was earlier in the rFVIIa cohort (mean=4.8 hours, 95% CI=3.0 to 6.7 hours) than in the standard cohort (mean=17.5 hours, 95% CI=12.5 to 22.6; p<0.001). CONCLUSIONS In patients with preinjury warfarin and tICH, use of rFVIIa was associated with a decreased time to normal INR. However, no difference in mortality was identified. Use of rFVIIa in patients on warfarin and tICH requires further study to demonstrate important patient-oriented outcomes.

Adenosine for wide-complex tachycardia: Efficacy and safety*

Objectives:To determine whether adenosine is useful and safe as a diagnostic and therapeutic agent for patients with undifferentiated wide QRS complex tachycardia. The etiology of sustained monomorphic wide QRS complex tachycardia is often uncertain acutely. Design:A retrospective observational study. Setting:Treatment associated with emergency visits at nine urban hospitals. Patients:Consecutive patients treated with adenosine for regular wide QRS complex tachycardia between 1991 and 2006. Interventions:Treatment with adenosine infusion. Measurements and Main Results:Measured outcomes included rhythm response to adenosine, if any, and all adverse effects. A positive response was defined as an observed change in rhythm including temporary atrioventricular conduction block or tachycardia termination. A primary adverse event was defined as emergent electrical or medical therapy instituted in response to an adverse adenosine effect. A rhythm diagnosis was made in each case. The characteristics of adenosine administration as a test for a supraventricular as opposed to ventricular tachycardia were determined, and the adverse event rates were calculated. A total of 197 patients were included: 104 (90%) of 116 (95% confidence interval, 83%–95%) and two (2%) of 81 (95% confidence interval, 0.3%–9%) supraventricular tachycardia and ventricular tachycardia patients demonstrated a response to adenosine, respectively. The odds of supraventricular tachycardia increased by a factor of 36 (95% confidence interval, 9–143) after a positive response to adenosine. The odds of ventricular tachycardia increased by a factor of 9 (95% confidence interval, 6–16) when there was no response to adenosine. The rate of primary adverse events for patients with supraventricular tachycardia and ventricular tachycardia was 0 (0%) of 116 (95% confidence interval, 0%–3%) and 0 (0%) of 81 (95% confidence interval, 0%–4%), respectively. Conclusions:Adenosine is useful and safe as a diagnostic and therapeutic agent for patients with regular wide QRS complex tachycardia.

Identification of low-risk patients with traumatic brain injury and intracranial hemorrhage who do not need intensive care unit admission

BACKGROUND Patients with traumatic brain injury (TBI) and traumatic intracranial hemorrhage are frequently admitted to the intensive care unit (ICU) but never require critical care interventions. Improved ICU triage in this patient population can improve resource utilization and decrease health care costs. We sought to identify a low-risk group of patients with TBI who do not require admission to an ICU. METHODS This is a retrospective cohort study of adult patients with TBI and traumatic intracranial hemorrhage. The need for ICU admission was defined as the presence of a critical care intervention. Patients were considered low risk if there was no critical care intervention before hospital admission. Measured outcomes included delayed critical care interventions at 48 hours and during hospitalization, mortality, and emergency surgery. RESULTS A total of 187 of 320 patients were considered low risk. In the low-risk group, two patients (1.1%; 95% confidence interval [CI], 0.1-3.8) had a delayed critical care intervention within 48 hours of admission and four patients (2.1%; 95% CI, 0.6-5.4) after 48 hours of admission. Two patients (1.1%; 95% CI, 0-3.8) in the low-risk group died. No patients in the low-risk group required neurosurgical intervention. CONCLUSION Patients with TBI without a critical care intervention before admission are at low risk for requiring future critical care interventions. Future studies are required to validate if this low-risk criteria can serve as a safe, cost-effective triage tool for ICU admission.

Prevalence and clinical import of thoracic injury identified by chest computed tomography but not chest radiography in blunt trauma: Multicenter prospective cohort study presented at the western regional society for academic emergency medicine meeting, March 2014, Irvine, CA; And the Society for Academic Emergency Medicine national meeting, May 2014, Dallas, TX.

STUDY OBJECTIVE Chest computed tomography (CT) diagnoses more injuries than chest radiography, so-called occult injuries. Wide availability of chest CT has driven substantial increase in emergency department use, although the incidence and clinical significance of chest CT findings have not been fully described. We determine the frequency, severity, and clinical import of occult injury, as determined by changes in management. These data will better inform clinical decisions, need for chest CT, and odds of intervention. METHODS Our sample included prospective data (2009 to 2013) on 5,912 patients at 10 Level I trauma center EDs with both chest radiography and chest CT at physician discretion. These patients were 40.6% of 14,553 enrolled in the parent study who had either chest radiography or chest CT. Occult injuries were pneumothorax, hemothorax, sternal or greater than 2 rib fractures, pulmonary contusion, thoracic spine or scapula fracture, and diaphragm or great vessel injury found on chest CT but not on preceding chest radiography. A priori, we categorized thoracic injuries as major (having invasive procedures), minor (observation or inpatient pain control >24 hours), or of no clinical significance. Primary outcome was prevalence and proportion of occult injury with major interventions of chest tube, mechanical ventilation, or surgery. Secondary outcome was minor interventions of admission rate or observation hours because of occult injury. RESULTS Two thousand forty-eight patients (34.6%) had chest injury on chest radiography or chest CT, whereas 1,454 of these patients (71.0%, 24.6% of all patients) had occult injury. Of these, in 954 patients (46.6% of injured, 16.1% of total), chest CT found injuries not observed on immediately preceding chest radiography. In 500 more patients (24.4% of injured patients, 8.5% of all patients), chest radiography found some injury, but chest CT found occult injury. Chest radiography found all injuries in only 29.0% of injured patients. Two hundred and two patients with occult injury (of 1,454, 13.9%) had major interventions, 343 of 1,454 (23.6%) had minor interventions, and 909 (62.5%) had no intervention. Patients with occult injury included 514 with pulmonary contusions (of 682 total, 75.4% occult), 405 with pneumothorax (of 597 total, 67.8% occult), 184 with hemothorax (of 230 total, 80.0% occult), those with greater than 2 rib fractures (n=672/1,120, 60.0% occult) or sternal fracture (n=269/281, 95.7% occult), 12 with great vessel injury (of 18 total, 66.7% occult), 5 with diaphragm injury (of 6, 83.3% occult), and 537 with multiple occult injuries. Interventions for patients with occult injury included mechanical ventilation for 31 of 514 patients with pulmonary contusion (6.0%), chest tube for 118 of 405 patients with pneumothorax (29.1%), and 75 of 184 patients with hemothorax (40.8%). Inpatient pain control or observation greater than 24 hours was conducted for 183 of 672 patients with rib fractures (27.2%) and 79 of 269 with sternal fractures (29.4%). Three of 12 (25%) patients with occult great vessel injuries had surgery. Repeated imaging was conducted for 50.6% of patients with occult injury (88.1% chest radiography, 11.9% chest CT, 7.5% both). For patients with occult injury, 90.9% (1,321/1,454) were admitted, with 9.1% observed in the ED for median 6.9 hours. Forty-four percent of observed patients were then admitted (4.0% of patients with occult injury). CONCLUSION In a more seriously injured subset of patients with blunt trauma who had both chest radiography and chest CT, occult injuries were found by chest CT in 71% of those with thoracic injuries and one fourth of all those with blunt chest trauma. More than one third of occult injury had intervention (37.5%). Chest tubes composed 76.2% of occult injury major interventions, with observation or inpatient pain control greater than 24 hours in 32.4% of occult fractures. Only 1 in 20 patients with occult injury was discharged home from the ED. For these patients with blunt trauma, chest CT is useful to identify otherwise occult injuries.

Risk of Traumatic Intracranial Hemorrhage in Patients with Head Injury and Preinjury Warfarin or Clopidogrel Use

OBJECTIVES Appropriate use of cranial computed tomography (CT) scanning in patients with mild blunt head trauma and preinjury anticoagulant or antiplatelet use is unknown. The objectives of this study were: 1) to identify risk factors for immediate traumatic intracranial hemorrhage (tICH) in patients with mild head trauma and preinjury warfarin or clopidogrel use and 2) to derive a clinical prediction rule to identify patients at low risk for immediate tICH. METHODS This was a prospective, observational study at two trauma centers and four community hospitals that enrolled adult emergency department (ED) patients with mild blunt head trauma (initial ED Glasgow Coma Scale [GCS] score 13 to 15) and preinjury warfarin or clopidogrel use. The primary outcome measure was immediate tICH, defined as the presence of ICH or contusion on the initial cranial CT. Risk for immediate tICH was analyzed in 11 independent predictor variables. Clinical prediction rules were derived with both binary recursive partitioning and multivariable logistic regression. RESULTS A total of 982 patients with a mean (± standard deviation [SD]) age of 75.4 (±12.6) years were included in the analysis. Sixty patients (6.1%; 95% confidence interval [CI] = 4.7% to 7.8%) had immediate tICH. History of vomiting (relative risk [RR] = 3.53; 95% CI = 1.80 to 6.94), abnormal mental status (RR = 2.85; 95% CI = 1.65 to 4.92), clopidogrel use (RR = 2.52; 95% CI = 1.55 to 4.10), and headache (RR = 1.81; 95% CI = 1.11 to 2.96) were associated with an increased risk for immediate tICH. Both binary recursive partitioning and multivariable logistic regression were unable to derive a clinical prediction model that identified a subset of patients at low risk for immediate tICH. CONCLUSIONS While several risk factors for immediate tICH were identified, the authors were unable to identify a subset of patients with mild head trauma and preinjury warfarin or clopidogrel use who are at low risk for immediate tICH. Thus, the recommendation is for urgent and liberal cranial CT imaging in this patient population, even in the absence of clinical findings.