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Dive into the research topics where Timothy C. Nunez is active.

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Featured researches published by Timothy C. Nunez.


Journal of Trauma-injury Infection and Critical Care | 2009

Predefined massive transfusion protocols are associated with a reduction in organ failure and postinjury complications.

Bryan A. Cotton; Brigham K. Au; Timothy C. Nunez; Oliver L. Gunter; Amy M. Robertson; Pampee P. Young

INTRODUCTION Massive transfusion (MT) protocols have been shown to improve survival in severely injured patients. However, others have noted that these higher fresh frozen plasma (FFP):red blood cell (RBC) ratios are associated with increased risk of organ failure. The purpose of this study was to determine whether MT protocols are associated with increased organ failure and complications. METHODS Our institutions exsanguination protocol (TEP) involves the immediate delivery of products in a 3:2 ratio of RBC:FFP and 5:1 for RBC:platelets. All patients receiving TEP between February 2006 and January 2008 were compared with a cohort (pre-TEP) of all patients from February 2004 to January 2006 that (1) went immediately to the operating room and (2) received MT (>or=10 units of RBC in first 24 hours). RESULTS Two hundred sixty-four patients met inclusion (125 in the TEP group, 141 in the pre-TEP). Demographics and Injury Severity Score were similar. TEP received more intraoperative FFP and platelets but less in first 24 hours (p < 0.01). There was no difference in renal failure or systemic inflammatory response syndrome, but pneumonia, pulmonary failure, open abdomens, and abdominal compartment syndrome were lower in TEP. In addition, severe sepsis or septic shock and multiorgan failure were both lower in the TEP patients (9% vs. 20%, p = 0.011 and 16% vs. 37%, p < 0.001, respectively). CONCLUSIONS Although MT has been associated with higher organ failure and complication rates, this risk appears to be reduced when blood products are delivered early in the resuscitation through a predefined protocol. Our institutions TEP was associated with a reduction in multiorgan failure and infectious complications, as well as an increase in ventilator-free days. In addition, implementation of this protocol was followed by a dramatic reduction in development of abdominal compartment syndrome and the incidence of open abdomens.


Journal of Trauma-injury Infection and Critical Care | 2009

Early prediction of massive transfusion in trauma: Simple as ABC (Assessment of Blood Consumption)?

Timothy C. Nunez; Igor Voskresensky; Lesly A. Dossett; Ricky Shinall; William D. Dutton; Bryan A. Cotton

BACKGROUND Massive transfusion (MT) occurs in about 3% of civilian and 8% of military trauma patients. Although many centers have implemented MT protocols, most do not have a standardized initiation policy. The purpose of this study was to validate previously described MT scoring systems and compare these to a simplified nonlaboratory dependent scoring system (Assessment of Blood Consumption [ABC] score). METHODS Retrospective cohort of all level I adult trauma patients transported directly from the scene (July 2005 to June 2006). Trauma-Associated Severe Hemorrhage (TASH) and McLaughlin scores calculated according to published methods. ABC score was assigned based on four nonweighted parameters: penetrating mechanism, positive focused assessment sonography for trauma, arrival systolic blood pressure of 90 mm Hg or less, and arrival heart rate > or = 120 bpm. Area under the receiver operating characteristic curve (AUROC) used to compare scoring systems. RESULTS Five hundred ninety-six patients were available for analysis; and the overall MT rate of 12.4%. Patients receiving MT had higher TASH (median, 6 vs. 13; p < 0.001), McLaughlin (median, 2.4 vs. 3.4; p < 0.001) and ABC (median, 1 vs. 2; p < 0.001) scores. TASH (AUROC = 0.842), McLaughlin (AUROC = 0.846), and ABC (AUROC = 0.842) scores were all good predictors of MT, and the difference between the scores was not statistically significant. ABC score of 2 or greater was 75% sensitive and 86% specific for predicting MT (correctly classified 85%). CONCLUSIONS The ABC score, which uses nonlaboratory, nonweighted parameters, is a simple and accurate in identifying patients who will require MT as compared with those previously published scores.


Journal of Trauma-injury Infection and Critical Care | 2011

Effect of high product ratio massive transfusion on mortality in blunt and penetrating trauma patients.

Susan E. Rowell; Barbosa Rr; Brian S. Diggs; Martin A. Schreiber; John B. Holcomb; Wade Ce; Karen J. Brasel; Gary Vercruysse; MacLeod J; Richard P. Dutton; Juan C. Duchesne; Norman E. McSwain; Peter Muskat; Johannigamn J; Henry Cryer; Areti Tillou; Cohen Mj; Jean-Francois Pittet; Paula L Knudson; De Moya Ma; Brandon H. Tieu; Susan I. Brundage; Lena M. Napolitano; Melissa E. Brunsvold; Kristen C. Sihler; Gregory J. Beilman; Andrew B. Peitzman; Zenait Ms; Jason L. Sperry; Louis H. Alarcon

BACKGROUND Recent data suggest that massively transfused patients have lower mortality rates when high ratios (>1:2) of plasma or platelets to red blood cells (RBCs) are used. Blunt and penetrating trauma patients have different injury patterns and may respond differently to resuscitation. This study was performed to determine whether mortality after high product ratio massive transfusion is different in blunt and penetrating trauma patients. METHODS Patients receiving 10 or more units of RBCs in the first 24 hours after admission to one of 23 Level I trauma centers were analyzed. Baseline physiologic and biochemical data were obtained. Univariate and logistic regression analyses were performed. Adjusted mortality in patients receiving high (≥ 1:2) and low (<1:2) ratios of plasma or platelets to RBCs was calculated for blunt and penetrating trauma patients. RESULTS The cohort contained 703 patients. Blunt injury patients receiving a high ratio of plasma or platelets to RBCs had lower 24-hour mortality (22% vs. 31% for plasma, p = 0.007; 20% vs. 30% for platelets, p = 0.032), but there was no difference in 30-day mortality (40% vs. 44% for plasma, p = 0.085; 37% vs. 44% for platelets, p = 0.063). Patients with penetrating injuries receiving a high plasma:RBC ratio had lower 24-hour mortality (21% vs. 37%, p = 0.005) and 30-day mortality (29% vs. 45%, p = 0.005). High platelet:RBC ratios did not affect mortality in penetrating patients. CONCLUSION Use of high plasma:RBC ratios during massive transfusion may benefit penetrating trauma patients to a greater degree than blunt trauma patients. High platelet:RBC ratios did not benefit either group.


International Journal of Emergency Medicine | 2011

Treatments for reversing warfarin anticoagulation in patients with acute intracranial hemorrhage: a structured literature review.

Brett F Bechtel; Timothy C. Nunez; Jennifer A Lyon; Bryan A. Cotton; Tyler W. Barrett

Study objectiveThe acute management of patients on warfarin with spontaneous or traumatic intracranial hemorrhage continues to be debated in the medical literature. The objective of this paper was to conduct a structured review of the medical literature and summarize the advantages and risks of the available treatment options for reversing warfarin anticoagulation in patients who present to the emergency department with acute intracranial hemorrhage.MethodsA structured literature search and review of articles relevant to intracranial hemorrhage and warfarin and treatment in the emergency department was performed. Databases for PubMed, CINAHL, and Cochrane EBM Reviews were electronically searched using keywords covering the concepts of anticoagulation drugs, intracranial hemorrhage (ICH), and treatment. The results generated by the search were limited to English- language articles and reviewed for relevance to our topic. The multiple database searches revealed 586 papers for review for possible inclusion. The final consensus of our comprehensive search strategy was a total of 23 original studies for inclusion in our review.ResultsWarfarin not only increases the risk of but also the severity of ICH by causing hematoma expansion. Prothrombin complex concentrate is statistically significantly faster at correcting the INR compared to fresh frozen plasma transfusions. Recombinant factor VIIa appears to rapidly reverse warfarins effect on INR; however, this treatment is not FDA-approved and is associated with a 5% thromboembolic event rate. Slow intravenous dosing of vitamin K is recommended in patients with ICH. The 30-day risk for ischemic stroke after discontinuation of warfarin therapy was 3-5%. The risks of not reversing the anticoagulation in ICH generally outweigh the risk of thrombosis in the acute setting.ConclusionsIncreasing numbers of patients are on anticoagulation including warfarin. There is no uniform standard for reversing warfarin in intracranial hemorrhage. Intravenous vitamin K in addition to fresh frozen plasma or prothrombin complex concentrate is recommended be used to reverse warfarin-associated intracranial hemorrhage. No mortality benefit for one treatment regimen over another has been shown. Emergency physicians should know their hospitals available warfarin reversal options and be comfortable administering these treatments to critically ill patients.


Current Opinion in Critical Care | 2009

Transfusion therapy in hemorrhagic shock.

Timothy C. Nunez; Bryan A. Cotton

Purpose of reviewBleeding and death from hemorrhage remain a leading cause of morbidity and mortality in the trauma population. Early resuscitation of these gravely injured patients has changed significantly over the past several years. The concept of damage control resuscitation has expanded significantly with the experience of the US military in southwest Asia. This review will focus on this resuscitation strategy of transfusing blood products (red cells, plasma, and platelets) early and often in the exsanguinating patient. Recent findingsIn trauma there are no randomized controlled trials comparing the current damage control hematology concept to more traditional resuscitation methods. But the overwhelming conclusion of the data available support the administration of a high ratio of plasma and platelets to packed red blood cells. Several large retrospective studies have shown ratios close to 1: 1 will result in higher survival. SummaryThe current evidence supports that the acute coagulopathy of trauma is present in a high percentage of trauma patients. Patients who will require a massive transfusion will have improved outcomes the earlier that this is identified and the earlier that damage control hematology is instituted. Current evidence does not describe the best ratio but the preponderance of the data suggests it should be greater than 2: 3 plasma-to-packed red blood cells.


Transfusion | 2010

Emergency department blood transfusion predicts early massive transfusion and early blood component requirement.

Timothy C. Nunez; William D. Dutton; Addison K. May; John B. Holcomb; Pampee P. Young; Bryan A. Cotton

BACKGROUND: The purpose of this study was to evaluate the ability of uncrossmatched transfusions in the emergency department (ED) to predict early (<6 hr) massive transfusion (MT) of red blood cells (RBCs) and blood components.


Journal of Trauma-injury Infection and Critical Care | 2011

Gender-based differences in mortality in response to high product ratio massive transfusion.

Susan E. Rowell; Ronald R. Barbosa; Carrie E. Allison; Van Py; Martin A. Schreiber; John B. Holcomb; Charles E. Wade; Karen J. Brasel; Gary Vercruysse; MacLeod J; Richard P. Dutton; Duchesne Jc; Norman E. McSwain; Peter Muskat; Johannigamn J; Henry Cryer; Tillou A; Mitchell J. Cohen; Pittet Jf; Knudson P; De Moya Ma; Tieu B; Susan I. Brundage; Lena M. Napolitano; Melissa E. Brunsvold; Kristen C. Sihler; Gregory J. Beilman; Peitzman Ab; Zenait Ms; Jason L. Sperry

BACKGROUND Recent data suggest that patients undergoing massive transfusion have lower mortality rates when ratios of plasma and platelets to red blood cells (RBCs) of ≥ 1:2 are used. This has not been examined independently in women and men. A gender dichotomy in outcome after severe injury is known to exist. This study examined gender-related differences in mortality after high product ratio massive transfusion. METHODS A retrospective study was conducted using a database containing massively transfused trauma patients from 23 Level I trauma centers. Baseline demographic, physiologic, and biochemical data were obtained. Univariate and logistic regression analyses were performed. Adjusted mortality in patients receiving high (≥ 1:2) or low (<1:2) ratios of plasma or platelets to RBCs was compared in women and men independently. RESULTS Seven hundred four patients were analyzed. In males, mortality was lower for patients receiving a high plasma:RBC ratio at 24 hours (20.6% vs. 33.0% for low ratio, p = 0.005) and at 30 days (34.9% vs. 42.8%, p = 0.032). Males receiving a high platelet:RBC ratio also had lower 24-hour mortality (17.6% vs. 31.5%, p = 0.004) and 30-day mortality (32.1% vs. 42.2%, p = 0.045). Females receiving high ratios of plasma or platelets to RBCs had no improvement in 24-hour mortality (p = 0.119 and 0.329, respectively) or 30-day mortality (p = 0.199 and 0.911, respectively). Use of high product ratio transfusions did not affect 24-hour RBC requirements in males or females. CONCLUSION Use of high plasma:RBC or platelet:RBC ratios in massive transfusion may benefit men more than women. This may be due to gender-related differences in coagulability. Further study is needed to determine whether separate protocols for women and men should be established.


Journal of Trauma-injury Infection and Critical Care | 2010

Postoperative neuromuscular blocker use is associated with higher primary fascial closure rates after damage control laparotomy.

Chadi T. Abouassaly; William D. Dutton; Victor Zaydfudim; Lesly A. Dossett; Timothy C. Nunez; Sloan B. Fleming; Bryan A. Cotton

BACKGROUND Failure to achieve fascial primary closure after damage control laparotomy (DCL) is associated with increased morbidity, higher healthcare expenditures, and a reduction in quality of life. The use of neuromuscular blocking agents (NMBA) to facilitate closure remains controversial and poorly studied. The purpose of this study was to determine whether exposure to NMBA is associated a higher likelihood of primary fascial closure. METHODS All adult trauma patients admitted between January 2002 and May 2008 who (1) went directly to the operating room, (2) were managed initially by DCL, and (3) survived to undergo a second laparotomy. Study group (NMBA+): those receiving NMBA in the first 24 hours after DCL. Comparison group (NMBA-): those not receiving NMBA in the first 24 hours after DCL. Primary fascial closure defined as fascia-to-fascia approximation by hospital day 7. RESULTS One hundred ninety-one patients met inclusion (92 in NMBA+ group, 99 in NMBA- group). Although the NMB+ patients were younger (31 years vs. 37 years, p = 0.009), there were no other differences in demographics, severity of injury, or lengths of stay between the groups. However, NMBA+ patients achieved primary closure faster (5.1 days vs. 3.5 days, p = 0.046) and were more likely to achieve closure by day 7 (93% vs. 83%, p = 0.023). After controlling for age, gender, race, mechanism, and severity of injury, logistic regression identified NMBA use as an independent predictor of achieving primary fascial closure by day 7 (OR, 3.24, CI: 1.15-9.16; p = 0.026). CONCLUSIONS Early NMBA use is associated with faster and more frequent achievement of primary fascial closure in patients initially managed with DCL. Patients exposed to NMBA had a three times higher likelihood of achieving primary fascial closure by hospital day 7.


Journal of Trauma-injury Infection and Critical Care | 2011

Specific abbreviated injury scale values are responsible for the underestimation of mortality in penetrating trauma patients by the injury severity score.

Susan E. Rowell; Ronald R. Barbosa; Brian S. Diggs; Martin A. Schreiber; John B. Holcomb; Wade Ce; Karen J. Brasel; Gary Vercruysse; MacLeod J; Richard P. Dutton; John R. Hess; Juan C. Duchesne; Norman E. McSwain; Peter Muskat; Johannigamn J; Henry Cryer; Areti Tillou; Cohen Mj; Jean-Francois Pittet; Paula L Knudson; M. A. De Moya; Brandon H. Tieu; Susan I. Brundage; Lena M. Napolitano; Melissa E. Brunsvold; Kristen C. Sihler; Gregory J. Beilman; Andrew B. Peitzman; Zenait Ms; Jason L. Sperry

BACKGROUND The Injury Severity Score (ISS) is widely used as a method for rating severity of injury. The ISS is the sum of the squares of the three worst Abbreviated Injury Scale (AIS) values from three body regions. Patients with penetrating injuries tend to have higher mortality rates for a given ISS than patients with blunt injuries. This is thought to be secondary to the increased prevalence of multiple severe injuries in the same body region in patients with penetrating injuries, which the ISS does not account for. We hypothesized that the mechanism-based difference in mortality could be attributed to certain ISS ranges and specific AIS values by body region. METHODS Outcome and injury scoring data were obtained from transfused patients admitted to 23 Level I trauma centers. ISS values were grouped into categories, and a logistic regression model was created. Mortality for each ISS category was determined and compared with the ISS 1 to 15 group. An interaction term was added to evaluate the effect of mechanism. Additional logistic regression models were created to examine each AIS category individually. RESULTS There were 2,292 patients in the cohort. An overall interaction between ISS and mechanism was observed (p = 0.049). Mortality rates between blunt and penetrating patients with an ISS between 25 and 40 were significantly different (23.6 vs. 36.1%; p = 0.022). Within this range, the magnitude of the difference in mortality was far higher for penetrating patients with head injuries (75% vs. 37% for blunt) than truncal injuries (26% vs. 17% for blunt). Penetrating trauma patients with an AIS head of 4 or 5, AIS abdomen of 3, or AIS extremity of 3 all had adjusted mortality rates higher than blunt trauma patients with those values. CONCLUSION Significant differences in mortality between blunt and penetrating trauma patients exist at certain ISS and AIS category values. The mortality difference is greatest for head injured patients.


Journal of Trauma-injury Infection and Critical Care | 2011

Variations between level i trauma centers in 24-hour mortality in severely injured patients requiring a massive transfusion

Charles E. Wade; del Junco Dj; John B. Holcomb; Karen J. Brasel; Gary Vercruysse; MacLeod J; Richard P. Dutton; Duchesne Jc; Norman E. McSwain; Peter Muskat; Johannigman J; Henry Cryer; Tillou A; Mitchell J. Cohen; Pittet Jf; Knudson P; De Moya Ma; Martin A. Schreiber; Tieu B; Susan I. Brundage; Lena M. Napolitano; Melissa E. Brunsvold; Kristen C. Sihler; Gregory J. Beilman; Peitzman Ab; Zenait Ms; Jason L. Sperry; Louis H. Alarcon; Martin A. Croce; Joseph P. Minei

BACKGROUND Significant differences in outcomes have been demonstrated between Level I trauma centers. Usually these differences are ascribed to regional or administrative differences, although the influence of variation in clinical practice is rarely considered. This study was undertaken to determine whether differences in early mortality of patients receiving a massive transfusion (MT, ≥ 10 units pf RBCs within 24 hours of admission) persist after adjustment for patient and transfusion practice differences. We hypothesized differences among centers in 24-hour mortality could predominantly be accounted for by differences in transfusion practices as well as patient characteristics. METHODS Data were retrospectively collected over a 1-year period from 15 Level I centers on patients receiving an MT. A purposeful variable selection strategy was used to build the final multivariable logistic model to assess differences between centers in 24-hour mortality. Adjusted odds ratios for each center were calculated. RESULTS : There were 550 patients evaluated, but only 443 patients had complete data for the set of variables included in the final model. Unadjusted mortality varied considerably across centers, ranging from 10% to 75%. Multivariable logistic regression identified injury severity score (ISS), abbreviated injury scale (AIS) of the chest, admission base deficit, admission heart rate, and total units of RBC transfused, as well as ratios of plasma:RBC and platelet:RBC to be associated with 24-hour mortality. After adjusting for severity of injury and transfusion, treatment variables between center differences were no longer significant. CONCLUSIONS In the defined population of patients receiving an MT, between-center differences in 24-hour mortality may be accounted for by severity of injury as well as transfusion practices.

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John B. Holcomb

University of Texas Health Science Center at Houston

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Pampee P. Young

Vanderbilt University Medical Center

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Brigham K. Au

University of Texas Health Science Center at Houston

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Henry Cryer

University of California

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Karen J. Brasel

Medical College of Wisconsin

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