Jay Menaker

Identifying Children at Very Low Risk of Clinically Important Blunt Abdominal Injuries

STUDY OBJECTIVE We derive a prediction rule to identify children at very low risk for intra-abdominal injuries undergoing acute intervention and for whom computed tomography (CT) could be obviated. METHODS We prospectively enrolled children with blunt torso trauma in 20 emergency departments. We used binary recursive partitioning to create a prediction rule to identify children at very low risk of intra-abdominal injuries undergoing acute intervention (therapeutic laparotomy, angiographic embolization, blood transfusion for abdominal hemorrhage, or intravenous fluid for ≥2 nights for pancreatic/gastrointestinal injuries). We considered only historical and physical examination variables with acceptable interrater reliability. RESULTS We enrolled 12,044 children with a median age of 11.1 years (interquartile range 5.8, 15.1 years). Of the 761 (6.3%) children with intra-abdominal injuries, 203 (26.7%) received acute interventions. The prediction rule consisted of (in descending order of importance) no evidence of abdominal wall trauma or seat belt sign, Glasgow Coma Scale score greater than 13, no abdominal tenderness, no evidence of thoracic wall trauma, no complaints of abdominal pain, no decreased breath sounds, and no vomiting. The rule had a negative predictive value of 5,028 of 5,034 (99.9%; 95% confidence interval [CI] 99.7% to 100%), sensitivity of 197 of 203 (97%; 95% CI 94% to 99%), specificity of 5,028 of 11,841 (42.5%; 95% CI 41.6% to 43.4%), and negative likelihood ratio of 0.07 (95% CI 0.03 to 0.15). CONCLUSION A prediction rule consisting of 7 patient history and physical examination findings, and without laboratory or ultrasonographic information, identifies children with blunt torso trauma who are at very low risk for intra-abdominal injury undergoing acute intervention. These findings require external validation before implementation.

Computed tomography alone for cervical spine clearance in the unreliable patient--are we there yet?

BACKGROUND Injuries to the cervical spine (CS) occur in 2% to 6.6% of blunt trauma patients. Studies have suggested that computed tomography (CT) alone is sufficient for CS clearance in unreliable patients based on follow-up magnetic resonance (MR) imaging not altering management. We hypothesized that an admission cervical spine CT with no acute injury-using new CT technology-is not sufficient for CS clearance in an unreliable patient. METHODS The trauma registry was used to identify all patients with blunt trauma who had CS imaging with a CT and MR between August 2004 and December 2005. During this time period, a clinical guideline was in place whereby patients who had persistently unreliable examinations had MR despite a normal admission CT. Medical records were reviewed for demographics, Glasgow Coma Scale (GCS) score at time of MR, and injury specific data. RESULTS Seven hundred thirty-four patients in total were identified. Two hundred three patients without obvious neurologic deficits but unreliable clinical examination, defined by a GCS score of </=14, had an initial cervical spine CT read by an attending trauma radiologist as having no acute injury. Mean age was 42.3 years (+/-20.4 years) and mean Injury Severity Score was 29.1 (+/-11.8). There were 135 (66.5%) men. Mechanism of injury included motor vehicle or motorcycle collision (48.8%), falls (25.4%), pedestrians struck (10.2%), assault (7.8%), and other (7.8%). One hundred eighty-four (90.6%) patients had a negative MR and collars were subsequently removed. After collar removal, no patient developed new neurologic deficit. Eighteen (8.9%) patients had an abnormal MR, 2 of which required operative repair and 14 required extended cervical collar use. Two patients had collars removed at the discretion of the attending surgeon. One patient had a suboptimal MR and was discharged in a collar with scheduled follow-up. CONCLUSION Newer generation CT continues to miss CS injuries in unreliable patients. MR changed the management in 7.9% of patients having had an admission CT with no acute injury. Thus, we recommend continued use of MR for CS clearance in the unreliable patient and ongoing evaluation as the quality of CT imaging continues to evolve.

A prospective multicenter comparison of levetiracetam versus phenytoin for early posttraumatic seizure prophylaxis.

BACKGROUND Brain Trauma Foundation guidelines recommend seizure prophylaxis for preventing early posttraumatic seizure (PTS). Phenytoin (PHE) is commonly used. Despite a paucity of data in traumatic brain injury, levetiracetam (LEV) has been introduced as a potential replacement, which is more costly but does not require serum monitoring. The purpose of this study was to compare the efficacy of PHE with that of LEV for preventing early PTS. METHODS Consecutive blunt traumatic brain injury patients undergoing seizure prophylaxis were prospectively enrolled at two Level 1 trauma centers during a 33-month period. Seizure prophylaxis was administered according to local protocol. Patients were monitored prospectively throughout their hospital stay for clinical evidence of seizure activity. PHE was compared with LEV with clinical early PTS as the primary outcome measure, defined as a seizure diagnosed clinically, occurring within 7 days of admission. RESULTS A total of 1,191 patients were screened for enrollment, after excluding 378 (31.7%) who did not meet inclusion criteria; 813 (68.3%) were analyzed (406 LEV and 407 PHE). There were no significant differences between LEV and PHE in age (51.7 [21.3] vs. 53.6 [22.5], p = 0.205), male (73.9% vs. 68.8%, p = 0.108), Injury Severity Score (ISS) (20.0 [10.0] vs. 21.0 [10.6], p = 0.175), Marshall score of 3 or greater (18.5% vs. 14.7%, p = 0.153), or craniectomy (8.4% vs. 11.8%, p = 0.106). There was no difference in seizure rate (1.5% vs.1.5%, p = 0.997), adverse drug reactions (7.9% vs. 10.3%, p = 0.227), or mortality (5.4% vs. 3.7%, p = 0.236). CONCLUSION In this prospective evaluation of early PTS prophylaxis, LEV did not outperform PHE. Cost and need for serum monitoring should be considered in guiding the choice of prophylactic agent. LEVEL OF EVIDENCE Therapeutic study, level III.

Management of post-traumatic retained hemothorax: a prospective, observational, multicenter AAST study.

Background: The natural history and optimal management of retained hemothorax (RH) after chest tube placement is unknown. The intent of our study was to determine practice patterns used and identify independent predictors of the need for thoracotomy. Methods: An American Association for the Surgery of Trauma multicenter prospective observational trial was conducted, enrolling patients with placement of chest tube within 24 hours of trauma admission and RH on subsequent computed tomography of the chest. Demographics, interventions, and outcomes were analyzed. Logistic regression analysis was used to identify the independent predictors of successful intervention for each of the management choices chosen and complications. Results: RH was identified in 328 patients from 20 centers. Video-assisted thoracoscopy (VATS) was the most commonly used initial procedure in 33.5%, but 26.5% required two and 5.4% required three procedures to clear RH or subsequent empyema. Thoracotomy was ultimately required in 20.4%. The strongest independent predictor of successful observation was estimated volume of RH ⩽300 cc (odds ratio [OR], 3.7 [2.0–7.0]; p < 0.001). Independent predictors of successful VATS as definitive treatment were absence of an associated diaphragm injury (OR, 4.7 [1.6–13.7]; p = 0.005), use of periprocedural antibiotics for thoracostomy placement (OR, 3.3 [1.2–9.0]; p = 0.023), and volume of RH ⩽900 cc (OR, 3.9 [1.4–13.2]; p = 0.03). No relationship between timing of VATS and success rate was identified. Independent predictors of the need for thoracotomy included diaphragm injury (OR, 4.9 [2.4–9.9]; p < 0.001), RH >900 cc (OR, 3.2 [1.4–7.5]; p = 0.007), and failure to give periprocedural antibiotics for initial chest tube placement (OR 2.3 [1.2–4.6]; p = 0.015). The overall empyema and pneumonia rates for RH patients were 26.8% and 19.5%, respectively. Conclusion: RH in trauma is associated with high rates of empyema and pneumonia. VATS can be performed with high success rates, although optimal timing is unknown. Approximately, 25% of patients require at least two procedures to effectively clear RH or subsequent pleural space infections and 20.4% require thoracotomy. Level of Evidence: II, prospective comparative study.

Independent Predictors of Enteric Fistula and Abdominal Sepsis After Damage Control Laparotomy: Results From the Prospective AAST Open Abdomen Registry

IMPORTANCE Enterocutaneous fistula (ECF), enteroatmospheric fistula (EAF), and intra-abdominal sepsis/abscess (IAS) are major challenges for surgeons caring for patients undergoing damage control laparotomy after trauma. OBJECTIVE To determine independent predictors of ECF, EAF, or IAS in patients undergoing damage control laparotomy after trauma, using the AAST Open Abdomen Registry. DESIGN The AAST Open Abdomen registry of patients with an open abdomen following damage control laparotomy was used to identify patients who developed ECF, EAF, or IAS and to compare these patients with those without these complications. Univariate analyses were performed to compare these groups of patients. Variables from univariate analyses differing at P < .20 were entered into a stepwise logistic regression model to identify independent risk factors for ECF, EAF, or IAS. SETTING Fourteen level I trauma centers. PARTICIPANTS A total of 517 patients with an open abdomen following damage control laparotomy. MAIN OUTCOMES AND MEASURES Complication of ECF, EAF, or IAS. RESULTS More patients in the ECF/EAF/IAS group than in the group without these complications underwent bowel resection (63 of 111 patients [57%] vs 133 of 406 patients [33%]; P < .001). Within the first 48 hours after surgery, the ECF/EAF/IAS group received more colloids (P < .03) and total fluids (P < .03) than did the group without these complications. The ECF/EAF/IAS group underwent almost twice as many abdominal reexplorations as did the group without these complications (mean [SD] number, 4.1 [4.1] vs 2.2 [3.4]; P < .001). After multivariate analysis, the independent predictors of ECF/EAF/IAS were a large bowel resection (adjusted odds ratio [AOR], 3.56 [95% CI, 1.88-6.76]; P < .001), a total fluid intake at 48 hours of between 5 and 10 L (AOR, 2.11 [95% CI, 1.15-3.88]; P = .02) or more than 10 L (AOR, 1.93 [95% CI, 1.04-3.57]; P = .04), and an increasing number of reexplorations (AOR, 1.14 [95% CI, 1.06-1.21]; P < .001). CONCLUSIONS AND RELEVANCE Large bowel resection, large-volume fluid resuscitation, and an increasing number of abdominal reexplorations were statistically significant predictors of ECF, EAF, or IAS in patients with an open abdomen after damage control laparotomy.

Development of posttraumatic empyema in patients with retained hemothorax: Results of a prospective, observational AAST study

BACKGROUND The natural history of retained hemothorax (RH), in particular factors contributing to the subsequent development of empyema, is not well known. The intent of our study was to establish the modern incidence of empyema among patients with trauma and RH and identify the independent predictors for development of this complication. METHODS An American Association for the Surgery of Trauma multicenter prospective observational trial was conducted, enrolling patients with placement of a thoracostomy tube within 24 hours of trauma admission, and subsequent development of RH was confirmed on computed tomography of the chest. Demographics, interventions, and outcomes were analyzed. Logistic regression analysis was used to identify the independent predictors for the development of empyema. RESULTS Among 328 patients with posttraumatic RH from the 20 participating centers, overall incidence of empyema was 26.8% (n = 88). On regression analysis, the presence of rib fractures (adjusted odds ratio [OR], 2.3; 95% confidence interval [CI], 1.3–4.1; p = 0.006), Injury Severity Score of 25 or higher (adjusted OR, 2.4; 95% CI, 1.3–4.4; p = 0.005), and the need for any additional therapeutic intervention (adjusted OR, 28.8; 95% CI, 6.6–125.5; p < 0.001) were found to be independent predictors for the development of empyema for patients with posttraumatic RH. Patients with empyema also had a significantly longer adjusted intensive care unit stay (adjusted mean difference, 4.1; 95% CI, 1.3–6.9; p = 0.008) and hospital stay (adjusted mean difference, −7.9; 95% CI, −12.7 to −3.2; p = 0.01). CONCLUSION Among patients with trauma and posttraumatic RH, the incidence of empyema was 26.8%. Independent predictors of empyema development after posttraumatic RH included the presence of rib fractures, Injury Severity Score of 25 or higher, and the need for additional interventions to evacuate retained blood from the thorax. Our findings highlight the need to minimize the risk associated with subsequent thoracic procedures among patients with critical illness and RH, through selection of the most optimal procedure for initial evacuation. LEVEL OF EVIDENCE Prognostic study, level III.

Use of Serum Biomarkers to Predict Cerebral Hypoxia after Severe Traumatic Brain Injury

The management of severe traumatic brain injury (TBI) focuses on prevention and treatment of secondary insults such as cerebral hypoxia (CH). There are a number of biomarkers that are thought to play a part in secondary injury following severe TBI. This study evaluates the association between S100β, neuron-specific enolase (NSE), and glial fibrillary acidic protein (GFAP), detected in the serum of severe TBI patients and CH as measured by brain tissue oxygen partial pressure (Pbo(2)). Patients with severe TBI were prospectively enrolled. Pressure times time (PTD; mm Hg*h), measuring the depth and duration of CH, was calculated for 12-h periods for episodes of moderate (Pbo(2) < 20 mm Hg) and severe (Pbo(2) < 15 mm Hg) CH, and compared to serum levels of S100β, NSE, and GFAP drawn prior to periods of monitoring. An adjusted mixed model analysis was applied as was receiver operating characteristic (ROC) curve analysis. Of 76 patients enrolled, 24 had Pbo(2) monitoring. One hundred and thirty serum samples were matched with 12-h periods of monitoring. Significant associations were found in adjusted analyses between increasing serum levels of S100β (coefficient=0.57, 0.56; p<0.001), NSE (coefficient=0.48, 0.52; p<0.001), and GFAP (coefficient=0.29, 0.30; p=0.003 and 0.002), and increasing PTD of moderate (Pbo(2)<20 mm Hg) and severe (Pbo(2)<15 mm Hg) CH. AUCs for the prediction of moderate and severe CH were 0.62 and 0.66 for S100β, 0.55 and 0.71 for NSE, and 0.50 and 0.62 for GFAP, respectively. Specificities were between 76% and 90% for S100β and NSE. S100β, NSE, and GFAP demonstrate promise as candidate serum markers of impending CH. The fact that these biomarker elevations occur prior to the onset of clinical manifestations suggests that we may be able to predict imminent events following TBI. Given the morbidity of CH, early intervention and prevention may have a significant impact on outcomes and help guide decisions about the timing of interventions.

Relationship of Serum and Cerebrospinal Fluid Biomarkers With Intracranial Hypertension and Cerebral Hypoperfusion After Severe Traumatic Brain Injury

BACKGROUND There is little that can be done to treat or reverse the primary injury that occurs at the time of a traumatic brain injury (TBI). Initial management of the patient with severe TBI focuses on prevention of subsequent secondary insults, namely, intracranial hypertension (ICH) and cerebral hypoperfusion (CH). Currently, there is no reliable way to predict which patients will develop ICH and CH other than clinical acumen; therefore, indicators of impending secondary intracranial insults may be useful in predicting these events and allowing for prevention and early intervention. This study was undertaken to investigate the relationship of cytokine levels with intracranial pressure (ICP) and cerebral perfusion pressure (CPP) in patients with severe TBI. METHODS Patients at the R Adams Cowley Shock Trauma Center were prospectively enrolled for a 6-month period. Inclusion criteria were older than 17 years, admission within the first 6 hours after injury, Glasgow Coma Scale<9 on admission, and placement of a clinically indicated ICP monitor. Serum and cerebrospinal fluid, when available, were collected on admission and twice daily for 7 days. Cytokine levels of interleukin (IL)-1β, IL-6, IL-8, IL-10, and tumor necrosis factor (TNF)-α were analyzed by multiplex bead array assays. Hourly values for ICP and CPP were recorded, and means, minimum (for CPP) or maximum (for ICP) values, percentage time ICP>20 mm Hg (%ICP20) and CPP<60 mm Hg (%CPP60), and cumulative Pressure Times Time Dose (PTD; mm Hg·h) for ICP>20 mm Hg (PTD ICP20) and CPP<60 mm Hg (PTD CPP60) were compared with the serum and cerebrospinal fluid levels that were drawn before 12-hour time periods (PRE) and after 12-hour time periods (POST) of monitoring. RESULTS Twenty-four patients were enrolled. In-hospital mortality was 12.5%, and good functional outcome was noted in 58%. Two hundred and seventy-five serum samples were taken and analyzed. IL-6 levels in the serum were found in the highest concentration of the cytokines measured. PTD ICP20 and PTD CPP60 were moderately correlated with increased PRE IL-8 levels (r=0.34, p<0.001; r=0.53, p<0.001). PTD ICP20 was also correlated with PRE TNF-α levels (r=0.27, p<0.001) as was PTD CPP60 (r=0.25, p<0.001). POST IL-8 levels were found to be correlated with PTD ICP20 (r=0.46, p<0.001) and PTD CPP60 (r=0.54, p<0.001). POST TNF-α was associated with PTD ICP20 (r=0.45, p<0.001). PTD CPP60 was also moderately correlated with POST TNF-α levels (r=0.26, p<0.001). When comparing patients with good versus poor outcome, median daily serum IL-8 levels were associated with poor outcome. CONCLUSIONS IL-8 and, to a lesser extent, TNF-α demonstrated the most promise in this study to be candidate serum markers of impending ICH and CH. The clinical relevance of this is the suggestion that we may be able to predict impending secondary insults after TBI before the clinical manifestation of these events. Given the known morbidity of ICH and CH, early intervention and prevention may have a significant impact on outcome. This becomes even more important when decisions must be made about timing of interventions. Increased levels of IL-8 and TNF-α in the serum during episodes of ICH and CH imply there are significant systemic effects of these events. These serum biomarkers are promising as diagnostic targets. In addition, further study of the precise role of these molecules may have significant implications for inflammatory system manipulation in the management of severe TBI.

Evaluation of multidetector computed tomography for penetrating neck injury: A prospective multicenter study

BACKGROUND: The purpose of this prospective multicenter study was to evaluate a clinical protocol integrating multidetector computed tomographic angiography (MDCTA) as the initial screening examination for the work-up of penetrating neck injury. METHODS: All penetrating neck injuries assessed at two Level I trauma centers (January 2009-July 2011) prospectively underwent a structured clinical examination. Those with hard signs of injury (active bleed, instability, expanding/pulsatile hematoma, bruit/thrill, hemoptysis, hematemesis, and air bubbling) underwent exploration, those who were asymptomatic were observed. The remainder, with soft signs underwent MDCTA. Sensitivity and specificity were tested against an aggregate gold standard of operative intervention, clinical follow-up, and when obtained, conventional angiography, bronchoscopy, esophagogram, and esophagoscopy. RESULTS: Four hundred fifty-three penetrating neck injuries were evaluated. Hard signs of vascular or aerodigestive tract injury were observed in 8.6% with an 89.7% incidence of clinically significant injury. 41.7% had no signs of injury and were observed with no missed injuries (follow-up, 2.6 days ± 1.1 days [1–58 days]). The remaining 225 (49.7%) underwent MDCTA (stab wound, 61.3%; gunshot wound, 37.8%; shotgun, 0.9%). The external wounds were in zone II (38.2%), multiple (28.9%), zone I (16.9%), and zone III (16.0%). Twenty-eight injuries were found in 22 patients (5 internal jugular-V, 2 external jugular-V, 1 vertebral-A, 7 common carotid-A, 2 internal carotid-A, 3 external carotid-A, 2 subclavian-A, 3 esophagus, and 3 tracheas). Five patients had false-positive findings (2 vascular and 3 aerodigestive tract). The 194 negative studies (follow-up, 5.5 days ± 7.5 days [1–27 days]) had no delayed diagnosis of injury. MDCTA was nondiagnostic in four patients (1.8%), secondary to artifact. One of these had a vertebral-A injury diagnosed at angiography. MDCTA achieved 100% sensitivity and 97.5% specificity in detecting all clinically significant injuries. CONCLUSION: In the initial evaluation of patients who have sustained penetrating neck trauma, physical examination can safely reduce unnecessary imaging. If imaging is required, MDCTA is a highly sensitive and specific screening modality for evaluating the vascular and aerodigestive structures in the neck. LEVEL OF EVIDENCE: II, prospective study.

The American association for the surgery of trauma prospective observational vascular injury treatment (PROOVIT) registry: Multicenter data on modern vascular injury diagnosis, management, and outcomes

BACKGROUND There is a need for a prospective registry designed to capture trauma-specific, in-hospital, and long-term outcomes related to vascular injury. METHODS The American Association for the Surgery of Trauma PROspective Vascular Injury Treatment (PROOVIT) registry was used to collect demographic, diagnostic, treatment, and outcome data on vascular injuries. RESULTS A total of 542 injuries from 14 centers (13 American College of Surgeons–verified Level I and 1 American College of Surgeons–verified Level II) have been captured since February 2013. The majority of patients are male (70.5%), with an Injury Severity Score (ISS) of 15 or greater among 32.1%. Penetrating mechanisms account for 36.5%. Arterial injuries to the head/neck (26.7%), thorax (10.4%), abdomen/pelvis (7.8%), upper extremity (18.4%), and lower extremity (26.0%) were identified, along with 98 major venous injuries. Hard signs of vascular injury, including hypotension (systolic blood pressure < 90 mm Hg, 11.8%), were noted in 28.6%. Prehospital tourniquet use for extremity injuries occurred in 20.2% (47 of 233). Diagnostic modalities included exploration (28.8%), computed tomographic angiography (38.9%), duplex ultrasound (3.1%), and angiography (10.7%). Arterial injuries included transection (24.3%), occlusion (17.3%), partial transection/flow limiting defect (24.5%), pseudoaneurysm (9.0%), and other injuries including intimal defects (22.7%). Nonoperative management was undertaken in 276 (50.9%), with failure in 4.0%. Definitive endovascular and open repair were used in 40 (7.4%) and 126 (23.2%) patients, respectively. Damage-control maneuvers were used in 57 (10.5%), including ligation (31, 5.7%) and shunting (14, 2.6%). Reintervention of initial repair was required in 42 (7.7%). Amputation was performed in 7.7% of extremity vascular injuries, and overall hospital mortality was 12.7%. Follow-up ranging from 1 month to 7 months is available for 48 patients via a variety of modalities, with reintervention required in 1 patient. CONCLUSION The PROOVIT registry provides a contemporary picture of the management of vascular injury. This resource promises to provide needed information required to answer questions about optimal diagnosis and management of these patients—including much needed long-term outcome data. LEVEL OF EVIDENCE Epidemiologic study, level V.