Carlton C Barnett

University of Colorado, Denver, CO, United States

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Publications (113)327.38 Total impact

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    ABSTRACT: The diagnosis of blunt abdominal trauma can be challenging and resource intensive. Observation with serial clinical assessments plays a major role in the evaluation of these patients, but the time required for intra-abdominal injury to become clinically apparent is unknown. The purpose of this study was to determine the amount of time required for an intra-abdominal injury to become clinically apparent after blunt abdominal trauma via physical examination or commonly followed clinical values. A retrospective review of patients who sustained blunt trauma resulting in intra-abdominal injury between June 2010 and June 2012 at a Level 1 academic trauma center was performed. Patient demographics, injuries, and the amount of time from emergency department admission to sign or symptom development and subsequent diagnosis were recorded. All diagnoses were made by computed tomography or at the time of surgery. Patient transfers from other hospitals were excluded. Of 3,574 blunt trauma patients admitted to the hospital, 285 (8%) experienced intra-abdominal injuries. The mean (SD) age was 36 (17) years, the majority were male (194 patients, 68%) and the mean (SD) Injury Severity Score (ISS) was 21 (14). The mean (SD) time from admission to diagnosis via computed tomography or surgery was 74 (55) minutes. Eighty patients (28%) required either surgery (78 patients, 17%) or radiographic embolization (2 patients, 0.7%) for their injury. All patients who required intervention demonstrated a sign or symptom of their intra-abdominal injury within 60 minutes of arrival, although two patients were intervened upon in a delayed fashion. All patients with a blunt intra-abdominal injury manifested a clinical sign or symptom of their intra-abdominal injury, resulting in their diagnosis within 8 hours 25 minutes of arrival to the hospital. All diagnosed intra-abdominal injuries from blunt trauma manifested clinical signs or symptoms that could prompt imaging or intervention, leading to their diagnosis within 8 hours 25 minutes of arrival to the hospital. All patients who required an intervention for their injury manifested a sign or symptom of their injury within 60 minutes of arrival. Therapeutic study, level IV. Epidemiologic study, level III.
    The journal of trauma and acute care surgery. 04/2014; 76(4):1020-3.
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    ABSTRACT: The liberal use of computed tomographic (CT) scanning during the evaluation of injured children has increased their exposure to the risks of ionizing radiation. We hypothesized that CT imaging performed for mechanism of injury alone is unnecessary and that serious or life-threatening injury is rarely identified. All pediatric blunt trauma team evaluations (age < 15 years) at a pediatric Level 2 trauma center over 72 months were reviewed. CT findings in patients with normal Glasgow Coma Scale (GCS) score, vital signs (VS), and physical examination (PE) (Group I) were compared with Group II (GCS score < 15), Group III (abnormal VS/PE), and Group IV (abnormal GCS score, VS/PE). Variables associated with any positive finding were entered into a multiple logistic regression model to assess for independent contributions. Each patient's total effective radiation dose from CT scans in millisieverts was calculated using an age-adjusted scale. A total 174 children met trauma team activation criteria (mean [SD] age, 7 [5] years; 63% male; mean [SD] Injury Severity Score [ISS], 10 [10]). A total of 153 (88%) were imaged by CT (I, 54 of 66; II, 25 of 25; III, 49 of 57; IV, 25 of 26). No patient in Group I had a serious finding on CT compared with Group II (17 of 77), III (25 of 111), and IV (18 of 72). Mortality was 4%. Radiation dose (mSv) from CT was not different among the groups (I, 17 [14]; II, 29 [13]; III, 21 [16]; IV, 27 [17]). By univariate analysis, GCS score of less than 15 (p < 0.01) and respiratory rate of greater than 30 (p = 0.09) were associated with a positive CT finding. By logistic regression analysis, GCS score of less than 15 remained the only variable associated significantly with a positive finding (odds ratio, 6.7; 95% confidence interval, 3-14; p < 0.01). In children imaged based only on mechanism, no patient had a serious positive finding but was subjected to radiation doses associated with an increased risk of future malignancy. The use of CT imaging in injured children in the absence of a physiologic or anatomic abnormality does not seem to be justified. Care management study, level IV.
    The journal of trauma and acute care surgery. 12/2013; 75(6):995-1001.
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    ABSTRACT: Intercellular adhesion molecule-1 (ICAM-1) modulates cell-cell adhesion and is a receptor for cognate ligands on leukocytes. Upregulation of ICAM-1 has been demonstrated in malignant transformation of adenomas and is associated with poor prognosis for many malignancies. ICAM-1 is upregulated on the invasive front of pancreatic metastases and melanomas. These data suggest that the upregulated ICAM-1 expression promotes malignant progression. We hypothesize that the downregulation of ICAM-1 will mitigate tumor progression. Mouse colon adenocarcinoma cells (MC38) were evaluated for the expression of ICAM-1 using Western immunoblot analysis. Short hairpin RNA (shRNA) transduction was used to downregulate ICAM-1. Tumor invasion determined via a modified Boyden chamber was used as a surrogate of tumor progression examining MC38 cells, MC38 ICAM-1 knockdowns, and MC38 transduced with vehicle control. The cells were cultured in full media for 24 h and serum-starved for 24 h. A total of 5 × 10(4) cells were plated and allowed to migrate for 24 h using full media with 10% fetal bovine serum as a chemoattractant. Inserts were fixed and stained with crystal violet. Blinded investigators counted the cells using a stereomicroscope. Statistical analysis was performed by analysis of variance with Fischer protected least significant difference and a P value of <0.05 was considered statistically significant. ICAM-1 was constitutively expressed on MC38 cells. Transduction with anti-ICAM-1 shRNA vector downregulated ICAM-1 protein expression by 30% according to the Western blot analysis (P < 0.03) and decreased ICAM-1 messenger RNA expression by 70% according to the reverse transcription-polymerase chain reaction. shRNA knockdown cells had a significant reduction in invasion >45% (P < 0.03). There were no significant differences between the invasion rates of MC38 and MC38 vehicle controls. Downregulation of ICAM-1 mitigates MC38 invasion. These data suggest that targeted downregulation of tumor ICAM-1 is a potential therapeutic target.
    Journal of Surgical Research 11/2013; · 2.02 Impact Factor
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    ABSTRACT: The optimal time to initiate venous thromboembolism pharmacoprophylaxis after blunt abdominal solid organ injury is unknown. Postinjury coagulation status was characterized using thromboelastography (TEG) in trauma patients with blunt abdominal solid organ injuries; TEG was divided into 12-hour intervals up to 72 hours. Forty-two of 304 patients (13.8%) identified underwent multiple postinjury thromboelastographic studies. Age (P = .45), gender (P = .45), and solid organ injury grade (P = .71) were similar between TEG and non-TEG patients. TEG patients had higher Injury Severity Scores compared with non-TEG patients (33.2 vs 18.3, respectively, P < .01). Among the TEG patients, the shear elastic modulus strength and maximum amplitude values began in the normal range within the first 12-hour interval after injury, increased linearly, and crossed into the hypercoagulable range at 48 hours (15.1 ± 1.9 Kd/cs and 57.6 ± 1.6 mm, respectively; P < .01, analysis of variance). Patients sustaining blunt abdominal solid organ injuries transition to a hypercoagulable state approximately 48 hours after injury. In the absence of contraindications, pharmacoprophylaxis should be considered before this time for effective venous thromboembolism prevention.
    American journal of surgery 10/2013; · 2.36 Impact Factor
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    ABSTRACT: INTRODUCTION: A child's risk of developing cancer from radiation exposure associated with computed tomography (CT) imaging is estimated to be as high as 1/500. Chest CT (CCT), often as part of a "pan-scan," is increasingly performed after blunt trauma in children. We hypothesized that routine CCT for the initial evaluation of blunt injured children does not add clinically useful information beyond chest radiograph (CXR) and rarely changes management. METHODS: Pediatric (<15 y) trauma team evaluations over 6 y at an academic Level I trauma center were reviewed. Demographic data, injuries, imaging, and management were identified for all patients undergoing CT. Effective radiation dose in milliSieverts (mSv) was calculated using age-adjusted scales. RESULTS: Fifty-seven of 174 children (33%) undergoing CT imaging had a CCT; 55 (97%) of these had a CXR. Pathology was identified in significantly fewer CXRs compared with CCTs (51% versus 83%, P < 0.001). All 7/57 (12%) emergent or urgent chest interventions were based on information from CXR. In 53 children (93%), the CCT was ordered as part of a pan-scan, resulting in a radiation dose of 37.69 ± 7.80 mSv from initial CT scans. Radiation dose was significantly greater from CCT than from CXR (8.7 ± 1.1 mSv versus 0.017 ± 0.002 mSv, P < 0.001). CONCLUSIONS: Clinically useful information found on CCT had good correlation to information obtained from CXR and did not change patient management, however, did add significantly to the radiation exposure of initial imaging. We recommend selective use of CCT, particularly in the presence of an abnormal mediastinal silhouette on CXR after a significant deceleration injury.
    Journal of Surgical Research 05/2013; · 2.02 Impact Factor
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    ABSTRACT: BACKGROUND: Urinary tract infection (UTI) in trauma patients is associated with increased mortality. Whether the urinalysis (UA) is an adequate test for a urinary source of fever in the ICU trauma patient has not been demonstrated. We hypothesized that the UA is a valuable screen for UTI in the febrile, critically ill trauma patient. STUDY DESIGN: All trauma ICU patients in our surgical ICU who had a fever (temperature >38.0°C), urinary catheter, UA, and a urine culture between January 1, 2011 and December 13, 2011 were reviewed. A positive UA was defined as positive leukocyte esterase, positive nitrite, WBC > 10/high power field, or presence of bacteria. A positive urine culture was defined as growth of ≥10(5) colony forming units (cfu) of an organism irrespective of the UA result or ≥10(3) cfu in the setting of a positive UA. A UTI was defined as positive urine culture without an alternative cause of the fever. RESULTS: There were 232 UAs from 112 patients that met criteria. The majority (75%) of patients were men; the mean age was 40 (±16) years. Of the 232 UAs, 90 (38.7%) were positive. There were 14 UTIs. The sensitivity, specificity, positive predictive value, and negative predictive value of the UA for UTI were 100%, 65.1%, 15.5%, and 100%, respectively. CONCLUSIONS: A negative UA reliably excludes a catheter-associated UTI in the febrile, trauma ICU patient with a 100% negative predictive value, and it can rapidly direct the clinician toward more likely sources of fever and reduce unnecessary urine cultures.
    Journal of the American College of Surgeons 04/2013; · 4.50 Impact Factor
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    ABSTRACT: BACKGROUND: Perioperative blood transfusion in pancreatic cancer patients is linked to decreased survival; however, a causal mechanism has not been determined. Previously we have shown that the plasma fraction of stored packed red blood cells (pRBCs) promotes pancreas cancer progression and associated morbidity. We hypothesize these untoward effects will be mitigated by use of a hemoglobin-based oxygen carrier (HBOC). METHODS: Cytokines and growth factors were measured in the plasma fraction from stored pRBCs and in an HBOC via cytokine array followed by formal enzyme-linked immunosorbent assay (ELISA). In an immunocompetent murine model, pancreas cancer progression was determined in vivo by bioluminescence, tumor weight, and number of metastases. RESULTS: Elevated levels of epidermal growth factor (EGF), platelet-derived growth factor BB (PDGF-BB), and regulated upon activation, normal T cell expressed and secreted (RANTES) were present in the plasma fraction of stored pRBCs, but were not found in the HBOC. Intravenous delivery of plasma fraction to mice with pancreatic cancer resulted in increased bioluminescence activity compared with mice that received HBOC. Metastatic events and pancreatic primary tumor weights were significantly higher in animals receiving plasma fraction from stored pRBCs compared with animals receiving HBOC. CONCLUSIONS: Intravenous receipt of the acellular plasma fraction of stored pRBCs promotes pancreatic cancer progression in an immunocompetent mouse model. These untoward events are mitigated by use of an HBOC.
    Annals of Surgical Oncology 01/2013; · 4.12 Impact Factor
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    ABSTRACT: Analogous to organ injury scales developed for trauma, a scoring system is needed for acute care surgery. The purpose of this study was to develop a disease severity score (DSS) for acute appendicitis, the most common surgical emergency. A panel of acute care surgery experts reviewed the literature and developed a DSS for acute appendicitis as follows: grade 1, inflamed; Grade 2, gangrenous; Grade 3, perforated with localized free fluid; Grade 4, perforated with a regional abscess; and Grade 5, perforated with diffuse peritonitis. We applied the DSS to 1,000 consecutive patients undergoing appendectomy from 1999 to 2009 and examined its association with outcomes (mortality, length of hospital stay, incidence of in-hospital, and postdischarge complications). Of the 1,000 patients, 82 were excluded owing to negative or interval appendectomy or advanced end-stage renal disease. Among 918 eligible patients, the DSS distribution was Grade 1 at 62.4%, Grade 2 at 13.0%, Grade 3 at 18.7%, Grade 4 at 4.4%, and Grade 5 at 1.5%. Statistical analyses indicated a stepwise risk increase in adverse outcomes with higher DSS grades (c statistics ≥ 0.75 for all outcomes). Covariates (age, sex, and type of surgical access) did not add to the predictive power of DSS. Based on this single-institution study, the proposed appendicitis DSS seems to be a useful tool. This DSS can inform future, national efforts, which can build on the knowledge provided by the present investigation. This DSS may be useful for comparing therapeutic modalities, planning resource use, improving programs, and adjusting reimbursement Epidemiologic study, level III.
    The journal of trauma and acute care surgery. 01/2013; 74(1):32-6.
  • Archives of surgery (Chicago, Ill.: 1960) 09/2012; 147(9):885. · 4.32 Impact Factor
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    ABSTRACT: Early postinjury death after packed red blood cell (pRBC) transfusion is attributed to uncontrolled hemorrhage and coagulopathy. The adverse immunomodulatory effects of blood transfusion are implicated in subsequent morbidity. We hypothesized that injured children requiring pRBC transfusion demonstrate patterns in outcome similar to those observed in adults. Our prospectively collected trauma registry was queried for demographics, treatment, and outcome (2006-2009). Outcomes of children who received pRBC transfusion were compared with those of age- and Injury Severity Score (ISS)-matched children who did not receive pRBC transfusion by both univariate and multivariable analysis. Eight percent (43/512) of injured children received a pRBC transfusion: 20 early and 23 late. The likelihood of pRBC transfusion increased with increasing ISS (ISS <15, 2%; ISS 16-25, 17%; ISS >25, 72%). One-half of injured children who received an early pRBC transfusion died; however, most deaths were because of central nervous system injury. Both ventilator and intensive care unit days were increased in children who received pRBC transfusion as compared with those who did not. Early pRBC transfusion is associated with a high mortality in children. Late blood transfusion is associated with worse outcomes, although this relationship may not be causal. This pilot study provides evidence of an association between pRBC transfusion, morbidity, and mortality among injured children that warrants refinement in larger, prospective investigations.
    Journal of Pediatric Surgery 08/2012; 47(8):1587-91. · 1.38 Impact Factor
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    ABSTRACT: In 1982, we reported our experience with abdominal vascular trauma, highlighting the critical role of hypothermia, acidosis, and coagulopathy. Damage control surgery was subsequently introduced to address this "lethal triad." The purpose of the present study was to evaluate the outcomes from our most recent 6-year experience compared with a cohort from 30 years ago. Patients with major abdominal vascular injuries were examined, and the most recent 6-year period was compared with archived data from a similar 6-year period three decades ago. The number of patients with major abdominal vascular injuries decreased from 123 patients in 1975 to 1980 to 64 patients in 2004 to 2009. The mean initial pH decreased from 7.21 to 6.96 (1975 to 1980 versus 2004 to 2009) for patients with overt coagulopathy. Despite increasingly protracted acidosis, mortality attributable to refractory coagulopathy decreased from 46% to 19% (1975 to 1980 versus 2004 to 2009, chi-square = 4.36, P = 0.04). No significant difference was found in mortality from exsanguinating injuries (43% versus 62%, 1975 to 1980 versus 2004 to 2009, chi-square = 1.96, P = 0.16). The prehospital transport times were unchanged (22 versus 20 min, 1975 to 1980 versus 2004 to 2009). Despite the administration of additional clotting factors and the advent of damage control surgery, the overall mortality remained largely unchanged (37% versus 33%, 1975 to 1980 versus 2004 to 2009, chi-square = 0.385, P = 0.53). The adoption of damage control surgery, including the implementation of a massive transfusion protocol, was associated with a reduction in mortality for abdominal vascular injuries due to coagulopathy; however, patients have continued to die of exsanguination.
    Journal of Surgical Research 05/2012; 177(2):320-5. · 2.02 Impact Factor
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    ABSTRACT: In vitro data suggest that erythrocytes undergo storage time-dependent degradation, eventuating in hemolysis. We hypothesize that transfusion of old blood, as compared with newer blood, results in a smaller increment in hematocrit. We performed an analysis of packed red blood cell transfusions administered in the surgical intensive care unit. Age of blood was analyzed as continuous, dichotomized at 14 days (old vs new), and grouped by weeks old. A total of 136 U of packed red blood cells were given to 52 patients; 110 (80.9%) were 14 days old or more. A linear, inverse correlation was observed between the age of blood and the increment in hematocrit (r(2) = -.18, P = .04). The increment in hematocrit was greater after transfusion of new as compared with old blood (5.6% vs 3.5%, respectively; P = .005). A linear relationship also was observed between the age of transfused blood in weeks and the increment in hematocrit (P = .02). There is an inverse relationship between the age of blood and the increment in hematocrit. The age of blood should be considered before transfusion of surgical patients with intensive care unit anemia.
    American journal of surgery 03/2012; 204(3):269-73. · 2.36 Impact Factor
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    ABSTRACT: The histologic presence of macrophages (tumor-associated macrophages, TAMs) and neutrophils (tumor-associated neutrophils, TANs) has been linked to poor clinical outcomes for solid tumors. The exact mechanism for this association with worsened prognosis is unclear. It has been theorized that TAMs are immunomodulated to an alternatively activated state and promote tumor progression. Similarly, TANs have been shown to promote angiogenesis and tumor detachment. TAMs and TANs were characterized for activation state and production of prometastatic mediators in an immunocompetent murine model of pancreatic adenocarcinoma. Specimens from liver metastases were evaluated by immunofluorescence and immunoblotting. TAMS have upregulated expression of CD206 and CD163 markers of alternative activation, (4.14 ± 0.55-fold and 7.36 ± 1.13-fold over control, respectively, P < 0.001) but do not have increased expression of classically activated macrophage markers CCR2 and CCR5. TAMs also express oncostatin M (OSM). We found that TANs, not TAMs, predominantly produce matrix metalloproteinase-9 (MMP-9) in this metastatic tumor microenvironment, while MMP-2 production is pan-tumoral. Moreover, increased expression of VEGF colocalized with TAMs as opposed to TANs. TAMs and TANs may act as distinct effector cells, with TAMs phenotypically exhibiting alternative activation and releasing OSM and VEGF. TANs are localized at the invasive front of the metastasis, where they colocalize with MMP-9. Improved understanding of these interactions may lead to targeted therapies for pancreas adenocarcinoma.
    AJP Regulatory Integrative and Comparative Physiology 03/2012; 302(9):R1067-75. · 3.28 Impact Factor
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    ABSTRACT: Perioperative blood transfusion has been linked to decreased survival in pancreatic cancer; however, the exact causal mechanism has not been elucidated. Allogeneic transfusions are known to expose patients to foreign cells and lipid mediators. We hypothesize that stored packed red cells (pRBCs) contain pro-cancer cytokines that augment tumor progression. We analyzed the plasma fraction of stored pRBCs for pro-cancer cytokines and evaluated the affect of both storage time and leukocyte reduction on these mediators. Chemiarray™ analysis for pro-cancer cytokines was performed on the acellular plasma fraction of stored leukocyte-reduced (LR) and non-leukocyte-reduced (NLR) pRBCs at day 1 (D.1-fresh) and day 42 (D.42-outdate) of storage. Elevated expression of monocyte chemotactic protein-1 (MCP-1), regulated on activation, normal T cell expressed and secreted (RANTES), angiogenin, tumor necrosis factor-alpha (TNF-α), epidermal growth factor (EGF), and platelet-derived growth factor (PDGF) was found. Specific enzyme-linked immunosorbent assay was performed for each of these factors in LR and NLR blood at D.1, day 28, and D.42. Data were analyzed by ANOVA. A p value ≤ 0.05 was considered significant; N ≥ 4 per group. Migration assays were performed using inhibitors of EGF (gefitinib) and PDGF (imatinib) on murine pancreatic adenocarcinoma cells (Pan02) exposed to D.1 and D.42 LR and NLR plasma. Proliferation assays were performed on Pan02 cells to test the inhibition of PDGF. MCP-1 levels increased with storage time in LR blood, 86.3 ± 6.3 pg/ml at D.1 vs. 121.2 ± 6.1 pg/ml at D.42 (p = 0.007), and NLR blood, 78.2 ± 7.3 pg/ml at D.1 vs. 647.8 ± 220.7 pg/ml at D.42 (p = 0.02). RANTES levels are lower in LR compared to NLR stored blood, 3.0 ± 1.9 vs. 15.8 ± 0.7 pg/ml at D.42 (p < 0.001), but similar in D.1 blood, 13.8 ± 1.8 pg/ml in LR vs. 12.0 ± 1.6 pg/ml in NLR. Angiogenin levels were different between LR and NLR blood, 0 pg/ml (undetectable) vs. 44.2 ± 3.7 pg/ml (p < 0.001). Storage time did not affect concentration. TNF-α levels were not different between LR and NLR blood, and there was no storage time effect on concentration. EGF and PDGF levels increased with storage time in NLR blood only, 216.4 ± 3.8 pg/ml at D.1 vs. 1,436.4 ± 238.6 pg/ml at D.42 for EGF (p = 0.001), and 61.6 ± 6.0 pg/ml at D.1 vs. 76.5 ± 1.7 pg/ml at D.42 (p = 0.003) for PDGF. Inhibition of EGF reduced migration in Pan02 cells treated with D.42 NLR blood, 245.9 ± 11.2 vs. 164.6 ± 10.6 cells/hpf (p < 0.001). Inhibition of PDGF had no effect on Pan02 migration and reduced cell proliferation in cells treated with D.42 NLR, 181.1 ± 1.5% over control vs. 157.5 ± 2.1% (p < 0.001). Pro-cancer cytokines that can augment tumor progression were identified in pRBCs. Some of these factors are present in fresh blood. The soluble factors identified herein may represent possible therapeutic targets to offset negative effects of transfusion. These data stress the need for efforts in cancer patients to reduce transfusion requirements if needed.
    Journal of Gastrointestinal Surgery 03/2012; 16(3):460-8. · 2.36 Impact Factor
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    ABSTRACT: Screening for blunt cerebrovascular injuries (BCVIs) and early treatment has virtually eliminated injury-related strokes. Screening protocols developed in the 1990s captured ∼80% of ultimately identified BCVI. With the availability of noninvasive diagnosis with computed tomographic angiography, broader indications for screening seem warranted. The purpose of this study was to identify injury patterns of patients with BCVI that are not currently recommended screening criteria. Our prospective BCVI database, initiated in 1997, was queried through December 2010. Indications for screening, injury mechanism, and outcomes were analyzed. Patients younger than 18 years were excluded. During the 14-year study period, 585 BCVIs were identified in 418 patients (66% men; age, 40 years ± 0.7 years). Eighty-three (20%) patients with BCVI did not have standard screening criteria; 66% were asymptomatic at diagnosis. Injury patterns in these patients included mandible fracture (27 patients), complex skull fractures (21 patients), traumatic brain injury with thoracic trauma (6 patients), scalp degloving (6 patients), and great vessel or cardiac injuries (4 patients). Other injuries (11 patients) and no injuries (8 patients) were identified in the remainder. Of the 307 asymptomatic patients who received antithrombotic treatment, one patient suffered stroke (0.3%) and one patient a transient ischemic attack (0.3%). A significant number of patients suffering BCVI are not captured by current screening guidelines. Screening for BCVI should be considered in patients with mandible fractures, complex skull fractures, traumatic brain injury with thoracic injuries, scalp degloving, and thoracic vascular injuries. II, prognostic study.
    The journal of trauma and acute care surgery. 02/2012; 72(2):330-5; discussion 336-7, quiz 539.
  • The journal of trauma and acute care surgery. 02/2012; 72(2):539.
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    ABSTRACT: Recent data indicate comparable efficacy and safety for levetiracetam (LEV) when compared with phenytoin (PHT) for prophylaxis of early seizures after traumatic brain injury. The purpose of this study was to conduct a cost-minimization analysis, from the perspective of both the acute care institution (cost) and patient (charges), comparing these two strategies. A decision tree was constructed to include baseline event probabilities obtained from detailed literature review, costs, and charges. Monte Carlo simulation was used to derive the mean costs and charges per patient treated with the LEV when compared with the PHT strategy. Adverse event probabilities, costs, charges, and frequency of laboratory determination for the PHT group were varied in sensitivity analyses. Literature review indicated equal efficacy of PHT versus LEV for early seizure prevention. The PHT strategy was superior to the LEV strategy from both the institutional (mean cost per patient $151.24 vs. $411.85, respectively) and patient (mean charge per patient $2,302.58 vs. $3,498.40, respectively) perspectives. Varying both baseline adverse event probabilities and frequency of laboratory testing did not alter the superiority of the PHT strategy. LEV replaced PHT as the dominant strategy only when the cost/charge of treating mental status deterioration was increased markedly above baseline. From both institutional and patient perspectives, PHT is less expensive than LEV for routine pharmacoprophylaxis of early seizures among traumatic brain injury patients. Pending compelling efficacy data, LEV should not replace PHT as a first-line agent for this indication.
    The journal of trauma and acute care surgery. 01/2012; 72(1):276-81.
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    ABSTRACT: The change in hematocrit (ΔHct) following packed red blood cell (pRBCs) transfusion is a clinically relevant measurement of transfusion efficacy that is influenced by post-transfusion hemolysis. Sexual dimorphism has been observed in critical illness and may be related to gender-specific differences in immune response. We investigated the relationship between both donor and recipient gender and ΔHct in an analysis of all pRBCs transfusions in our surgical intensive care unit (2006-2009). The relationship between both donor and recipient gender and ΔHct (% points) was assessed using both univariate and multivariable analysis. A total of 575 units of pRBCs were given to 342 patients; 289 (49.9%) donors were male. By univariate analysis, ΔHct was significantly greater for female as compared to male recipients (3.81% versus 2.82%, resp., P < 0.01). No association was observed between donor gender and ΔHct, which was 3.02% following receipt of female blood versus 3.23% following receipt of male blood (P = 0.21). By multivariable analysis, recipient gender remained associated significantly with ΔHct (P < 0.01). In conclusion, recipient gender is independently associated with ΔHct following pRBCs transfusion. This association does not appear related to either demographic or anthropomorphic factors, raising the possibility of gender-related differences in recipient immune response to transfusion.
    ISRN hematology. 01/2012; 2012:298345.
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    ABSTRACT: Multiple techniques have been introduced to obtain fascial closure for the open abdomen. Vacuum-assisted closure has reduced but not eliminated the use of either split-thickness skin grafts to cover the exposed bowel or mesh (prosthetic or biological) approximation of the fascia. We hypothesized that a sequential closure technique performed by a systematic protocol would achieve a higher rate of primary fascial closure than other described techniques. Our technique of sequential fascial closure was initiated in 2005. Patients with a postinjury open abdomen undergoing the technique were compared with those patients who did not follow the protocol. In brief, vacuum-assisted closure white sponges cover the bowel; the fascia is placed under moderate tension over the white sponges with no. 1-polydioxanone sutures; the black sponge is placed on top of this with the standard occlusive dressing; patients undergo partial fascial closure and replacement of the sponge sandwich every 2 days until completely closed. Protocol violations were defined as not returning to the operating room every other day and absence of fascial retention sutures. Patients who died before return to the operating room in the first 48 hours were excluded. One hundred consecutive patients underwent damage control surgery during the five-year study period and survived to second laparotomy; 49 patients attained fascial closure at the second laparotomy. Fifty-one patients required an open abdomen after the second laparotomy and comprise the study population. The majority were men (80%) with a mean age of 34.7 years ± 2.0 years, mean injury severity score of 37.1 ± 2.4, and mean abdominal trauma index of 26.4 ± 2.1. Average initial base deficit was 15.7 ± 0.6 and 24-hour red cell transfusions were 20.4 ± 2.4 units. Of the 51 patients, 29 followed the protocol and 100% had fascial closure. Of the 22 patients who did not follow the protocol, 12 (55%) attained fascial closure. There were no significant differences in injury severity score, abdominal trauma index, base deficit, or red cell transfusions between the two groups. A methodical approach with sequential fascial closure achieves 100% fascial approximation in our experience. This technique reduces the morbidity of the open abdomen and the cost of either complex abdominal reconstruction or biological mesh insertion.
    The journal of trauma and acute care surgery. 01/2012; 72(1):235-41.
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    ABSTRACT: Although blunt cerebrovascular injuries (BCVIs) are a well-recognized sequela of trauma in adults, there have been few reports in children. The investigators questioned whether adult screening protocols are appropriate in the pediatric population. The purpose of this study was to describe the incidence, injury patterns, and stroke rates of pediatric patients sustaining BCVIs. Pediatric patients (aged ≤ 18 years) diagnosed with BCVIs at a regional level I trauma center and a pediatric level I trauma center since 1996 were reviewed. Forty-five patients sustained BCVIs (60% male; mean age, 13 ± .7 years; mean Injury Severity Score, 23 ± 2). Three patients exsanguinated, and 10 presented with stroke; neurologic changes occurred 17 ± 6 hours after injury (range, 1-72 hours). Screening indications were present in 30%. Thirty-two asymptomatic patients were diagnosed. All but 1 received antithrombotic agents; 1 patient had neurologic deterioration despite heparinization. Comparing asymptomatic patients with those with stroke, there was a significant difference in age (15 vs 11 years). More than two-thirds of patients presenting with stroke did not have screening indications according to adult protocols. With the availability of noninvasive diagnostic imaging such as computed tomographic angiography, broader screening guidelines for children should be instituted.
    American journal of surgery 12/2011; 204(1):7-10. · 2.36 Impact Factor

Publication Stats

2k Citations
327.38 Total Impact Points

Institutions

  • 2000–2013
    • University of Colorado
      • Department of Surgery
      Denver, CO, United States
  • 2009–2012
    • Mental Health Center of Denver
      Denver, Colorado, United States
  • 2010
    • University of Colorado Hospital
      Denver, Colorado, United States
    • Penn State Hershey Medical Center and Penn State College of Medicine
      • Department of Surgery
      Hershey, PA, United States
    • Wayne State University
      • Department of Emergency Medicine
      Detroit, MI, United States
  • 2007–2010
    • University of Texas Southwestern Medical Center
      • • Division of Surgical Oncology
      • • Department of Surgery
      Dallas, TX, United States
  • 2000–2001
    • University of Texas MD Anderson Cancer Center
      • Department of Surgical Oncology
      Houston, TX, United States