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Dive into the research topics where Ronald V. Maier is active.

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Featured researches published by Ronald V. Maier.


Journal of Trauma-injury Infection and Critical Care | 2008

An FFP: PRBC transfusion ratio >/=1:1.5 is associated with a lower risk of mortality after massive transfusion.

Jason L. Sperry; Juan B. Ochoa; Scott R. Gunn; Louis H. Alarcon; Joseph P. Minei; Joseph Cuschieri; Matthew R. Rosengart; Ronald V. Maier; Timothy R. Billiar; Andrew B. Peitzman; Ernest E. Moore

OBJECTIVE The detrimental effects of coagulopathy, hypothermia, and acidosis are well described as markers for mortality after traumatic hemorrhage. Recent military experience suggests that a high fresh frozen plasma (FFP):packed red blood cell (PRBC) transfusion ratio improves outcome; however, the appropriate ratio these transfusion products should be given remains to be established in a civilian trauma population. METHODS Data were obtained from a multicenter prospective cohort study evaluating clinical outcomes in blunt injured adults with hemorrhagic shock. Those patients who required >/=8 units PRBCs within the first 12 hours postinjury were analyzed (n = 415). RESULTS Patients who received transfusion products in >/=1:1.50 FFP:PRBC ratio (high F:P ratio, n = 102) versus <1:1.50 FFP:PRBC ratio (low F:P, n = 313) required significantly less blood transfusion at 24 hours (16 +/- 9 units vs. 22 +/- 17 units, p = 0.001). Crude mortality differences between the groups did not reach statistical significance (high F:P 28% vs. low F:P 35%, p = 0.202); however, there was a significant difference in early (24 hour) mortality (high F:P 3.9% vs. low F:P 12.8%, p = 0.012). Cox proportional hazard regression revealed that receiving a high F:P ratio was independently associated with 52% lower risk of mortality after adjusting for important confounders (HR 0.48, p = 0.002, 95% CI 0.3-0.8). A high F:P ratio was not associated with a higher risk of organ failure or nosocomial infection, however, was associated with almost a twofold higher risk of acute respiratory distress syndrome, after controlling for important confounders. CONCLUSIONS In patients requiring >/=8 units of blood after serious blunt injury, an FFP:PRBC transfusion ratio >/=1:1.5 was associated with a significant lower risk of mortality but a higher risk of acute respiratory distress syndrome. The mortality risk reduction was most relevant to mortality within the first 48 hours from the time of injury. These results suggest that the mortality risk associated with an FFP:PRBC ratio <1:1.5 may occur early, possibly secondary to ongoing coagulopathy and hemorrhage. This analysis provides further justification for the prospective trial investigation into the optimal FFP:PRBC ratio required in massive transfusion practice.


Journal of Emergency Medicine | 2002

An analysis of advanced prehospital airway management.

Eileen M. Bulger; Michael K. Copass; Ronald V. Maier; Jonathan Larsen; Justin Knowles; Gregory J. Jurkovich

Considerable controversy persists regarding the optimal means and indications for airway management, the utility of paralytic agents to facilitate intubation, and the indications for advanced airway access techniques in the prehospital setting. To describe the use of intubation and advanced airway management in a system with extensive experience with both the use of paralytic agents and surgical airway techniques, a retrospective review was conducted of all prehospital airway procedures from January 1997 through November 1999. Data collected included demographics, airway management techniques, use of paralytic agents, and immediate outcome. The results showed there were 2700 patients intubated out of 50,118 patient encounters (5.4%). The indications for intubation included medical emergency in 82% of patients and traumatic injury in 18%. Fifty percent of patients were intubated with the use of succinylcholine. The overall oral intubation success rate was 98.4% and definitive airway access was achieved in all but 12 patients (0.6%), with 30 patients receiving surgical airway access (1%). The successful intubation rate for patients receiving paralytic agents was 97.8%. Previously published rates of prehospital surgical airway access range from 3.8 to 14.9% of patients. In this study, only 1.1% of patients required a surgical airway. We attribute this low rate to the use of paralytic agents. The availability of paralytic agents also allows expansion of the indications for prehospital airway control.


Journal of Surgical Research | 1984

Microthrombosis during endotoxemia: Potential role of hepatic versus alveolar macrophages

Ronald V. Maier; Gregory B. Hahnel

Macrophages (M phi) produce multiple inflammatory mediators which may contribute to the pathophysiological processes seen during sepsis. Since diffuse microthrombosis has been implicated as a potential etiology for organ dysfunction and failure in sepsis, the present study examined the production of procoagulant activity (PCA) by M phi in response to endotoxin, characterized the activity, and evaluated methods to modify the response. Since hepatic and pulmonary dysfunction is a common complication of sepsis, rabbit M phi were isolated from both pulmonary (A-M phi) and hepatic (H-M phi) sites. Both M phi populations produced PCA in response to endotoxin in vitro. There is a rapid rise in activity with a peak at 20- to 30+ fold over background levels at 8 hr poststimulation. Although similar in their ability to enhance coagulation, the two M phi PCAs were shown to differ markedly in other biochemical and functional assays. The A-M phi PCA in contrast to the H-M phi PCA, was resistant to heat inactivation, serine protease inhibition, and warfarin pretreatment, while indomethacin (a prostaglandin synthesis inhibitor) blocked A-M phi PCA production but not the H-M phi response. Corticosteroids totally blocked PCA production by both M phi populations. Endotoxin, therefore, induces a rapid increase in M phi PCA, and the magnitude and rapidity of the response argue for a potentially significant pathophysiologic role, in vivo. Although derived from a common progenitor, A-M phi and H-M phi produce a functionally discreet PCA. This differential response may partially explain the contradictory results obtained in studies using various cellular metabolism inhibitors, e.g., indomethacin and steroids.(ABSTRACT TRUNCATED AT 250 WORDS)


Archive | 2008

Shock and Resuscitation

Avery B. Nathens; Ronald V. Maier

In 1872, Gross referred to shock as the “manifestation of the rude unhinging of the machinery of life.”1 We now know that shock, at its most fundamental level, represents the clinical syndrome arising as a result of inadequate tissue perfusion. The discrepancy between substrate delivery and the cellular substrate requirement leads to cellular metabolic dysfunction. Inadequate oxygen delivery is implicated as the principal defect in shock states. The clinical manifestations of shock are caused by end-organ dysfunction secondary to impaired perfusion and the body’s sympathetic and neuroendocrine response to an insufficient cellular supply/demand ratio for oxygen.


Journal of The American College of Surgeons | 2013

Experience with an Enteral-Based Nutritional Support Regimen in Critically-Ill Trauma Patients

Christina Chung; Ryan Whitney; Callie M. Thompson; Tam N. Pham; Ronald V. Maier; Grant E. O'Keefe

BACKGROUND Assuring adequate enteral nutritional support in critically ill patients is challenging. By describing our experience, we sought to characterize the challenges, benefits, and complications of an approach that stresses enteral nutrition. STUDY DESIGN We examined nutritional support received by victims of blunt trauma from 8 trauma centers. We grouped patients according to mean daily enteral caloric intake during the first 7 days. Group 1 received the fewest (0 kcal/kg/d) and group 5 the greatest (16 to 30 kcal/kg/d) number of calories in the first week. We focused our analyses on the patients remaining in the ICU for 8 days or longer and compared clinical outcomes among the groups. RESULTS There were 1,100 patients in the ICU for 8 days or longer. Patients receiving the greatest number of enteral calories during the first week (group 5) had the highest incidence of ventilator-associated pneumonia (49%) and the lowest incidence of bacteremia (14%). Use of parenteral nutrition was associated with bacteremia (adjusted odds ratio = 2.5; 95% CI, 1.8-3.5), ventilator-associated pneumonia (adjusted odds ratio = 2.4; 95% CI, 1.7-3.3), and death (adjusted odds ratio = 1.9; 95% CI, 1.1-3.1). CONCLUSIONS Enteral caloric intake during the first week was related to the pattern and severity of injury and was associated with important infectious outcomes. Our observations support moderating enteral intake during the first week after injury and avoiding parenteral nutrition.


JAMA Surgery | 2016

Analysis of Risk Factors for Patient Readmission 30 Days Following Discharge From General Surgery

Lisa K. McIntyre; Saman Arbabi; Ellen Robinson; Ronald V. Maier

IMPORTANCE Previous studies investigating patients at risk for hospital readmissions focus on medical services and have found chronic conditions as contributors. Little is known, however, of the characteristics of patients readmitted from surgical services. OBJECTIVE Surgical patients readmitted within 30 days following discharge were analyzed to identify opportunities for intervention in a cohort that may differ from the medical population. DESIGN, SETTING, AND PARTICIPANTS Medical record review of patients readmitted to any service within 30 days of discharge from the general surgery service to characterize index and readmission data between July 1, 2014, and June 30, 2015, at a Level I trauma center and safety-net hospital. MAIN OUTCOMES AND MEASURES Reasons for readmission identified by manual medical record review and risk factors identified via statistical analysis of all discharges during this period. RESULTS One hundred seventy-three patients were identified as being unplanned readmissions within 30 days among 2100 discharges (8.2%). Of these 173 patients, 91 were men. Common reasons for readmission included 29 patients with injection drug use who were readmitted with soft tissue infections at new sites (16.8% of readmissions), 25 with disposition support issues (14.5%), 23 with infections not detectable during index admission (13.3%), and 16 with sequelae of their injury or condition (9.2%). Sixteen patients were identified as having a likely preventable complication of care (9.2%), and 2 were readmitted owing to deterioration of medical conditions (1.2%). On univariate and multivariate analyses, female sex (men to women risk of readmission odds ratio [OR], 0.5; 95% CI, 0.37-0.71; P < .001), presence of diabetes (OR, 1.7; 95% CI, 1.1-2.6; P = .009), sepsis on admission (OR, 1.7; 95% CI, 1.05-2.6; P = .03), or intensive care unit stay during index admission (OR, 1.7; 95% CI, 1.2-2.4; P = .002), as well as discharge to respite care (OR, 2.3; 95% CI, 1.2-4.5; P = .01) and payer status (Medicaid/Medicare compared with commercial OR, 2.0; 95% CI, 1.3-3.0; P = .002) , were identified as risk factors for readmission. CONCLUSIONS AND RELEVANCE Many readmissions may be unavoidable in our current paradigms of care. While medical comorbidities are contributory, a large number of readmissions were not caused by suboptimal medical care or deterioration of medical conditions but by confounding issues of substance abuse or homelessness. Identification of the highest risk cohort for readmission can allow more targeted intervention for similar populations with socially challenged patients.


Journal of Trauma-injury Infection and Critical Care | 2008

Inflammation and the host response to injury, a large-scale collaborative project: Patient-oriented research core-standard operating procedures for clinical care VII-guidelines for antibiotic administration in severely injured patients

Michael A. West; Ernest E. Moore; Michael B. Shapiro; Avery B. Nathens; Joseph Cuschieri; Jeffrey L. Johnson; Brian G. Harbrecht; Joseph P. Minei; Paul E. Bankey; Ronald V. Maier

When the clinical decision to treat a critically ill patient with antibiotics has been made, one must attempt to identify the site of infection based on clinical signs and symptoms, laboratory or diagnostic radiology studies. Identification of site requires, examination of patient, inspection of all wounds, chest radiograph, and calculation of clinical pulmonary infection score if ventilated, obtaining blood cultures, urinalysis, and line change if clinical suspicion of central venous catheter (CVC) source. If it is impossible to identify site, obtain cultures from all accessible suspected sites and initiate empiric, broad spectrum antibiotics. If likely site can be identified answer these questions: Is intra-abdominal site suspected? Is pulmonary source of infection suspected? Is skin, skin structure or soft tissue site suspected? If yes, does the patient have clinical signs suspicion for necrotizing soft tissue infection (NSTI)? Is a CVC infection suspected? Risk factors for more complicated infections are discussed and specific antibiotic recommendations are provided for each type and severity of clinical infection. Decision to continue, discontinue and/or alter antibiotic/antimicrobial treatment should be based on the clinical response to treatment, diagnostic or interventional findings, and culture and sensitivity data, bearing in mind that not all patients with infections will have positive cultures because of limitations of specimen handling, microbiology laboratory variations, time between specimen acquisition and culture, or presence of effective antibiotics at the time that specimens were obtained. It should also be noted that not all patients with increased temperature/WBC have an infection. Discontinuation of antibiotics is appropriate if cultures and other diagnostic studies are negative.


Annals of Emergency Medicine | 1992

State trauma system evaluation: A unique and comprehensive approach

Thomas J. Esposito; James Nania; Ronald V. Maier

We detail the unique and comprehensive approach to evaluation taken by the state of Washington before development and legislation of a statewide trauma system plan. The various types of data collected and the rationale for collecting them are discussed. In addition, the advantages, disadvantages, and limitations of individual study methods are elucidated. These data-gathering approaches may serve as a guide for other states or regions contemplating comprehensive trauma system development.


American Journal of Surgery | 1992

Resuscitative thoracotomy performed in the operating room

Gregory J. Jurkovich; Thomas J. Esposito; Ronald V. Maier

The efficacy of resuscitative thoracotomy in the trauma patient has been questioned. Survival rates are variable, but a review of resuscitative thoracotomy in the emergency department of our institution documented an overall survival rate of only 1.8%. Higher survival rates may be anticipated in patients initially presenting with signs of life who can be transported directly to the operating room prior to the need for resuscitative thoracotomy. To test this hypothesis, the clinical course of all injured patients undergoing urgent or exigent thoracotomy in the operating room between July 1983 and June 1989 was reviewed. There were 34 patients undergoing exigent/resuscitative thoracotomy, 8 with penetrating injuries, 25 with blunt trauma to multiple systems, and 1 with isolated blunt chest trauma. Eight median sternotomies were performed and 26 left or bilateral thoracotomies. Twenty-six patients underwent concurrent exploratory celiotomy. The overall survival rate was 9% (3 of 34). The survival rate for patients with penetrating injuries was 37.5% (3 of 8) and 0% (0 of 26) for those with blunt trauma. Fifty-four patients underwent urgent/nonresuscitative thoracotomy with an overall survival rate of 74% (40 of 54). Combined group survival rates were 49% overall, 77% for patients with penetrating wounds, and 22% for patients with blunt trauma. These data underscore the futility of resuscitative thoracotomy in patients with blunt trauma who have deteriorated to the point of being in extremis. The relatively high salvage rates in patients with penetrating injuries support continued use of resuscitative thoracotomy when vital signs are lost, particularly if the injury is to the thorax. Variability in reported survival rates may be primarily due to the mix of patients with blunt trauma and penetrating injuries and disagreement as to what constitutes a resuscitative thoracotomy.


Journal of Trauma-injury Infection and Critical Care | 2009

Preinjury statin use is associated with a higher risk of multiple organ failure after injury: a propensity score adjusted analysis.

Matthew D. Neal; Joseph Cushieri; Matthew R. Rosengart; Louis H. Alarcon; Ernest E. Moore; Ronald V. Maier; Joseph P. Minei; Timothy R. Billiar; Andrew B. Peitzman; Jason L. Sperry

BACKGROUND Recent studies suggest that statin use may improve outcome in critically ill patients. This has been attributed to the pleiomorphic effect and modulation of inflammatory mediators that occurs with statin use. We sought to determine whether preinjury statin (PIS) use was associated with improved outcome in severely injured blunt trauma patients. METHODS Data were obtained from a multicenter prospective cohort study evaluating outcomes in blunt injured adults with hemorrhagic shock. Patients aged 55 years and older were analyzed. Those with isolated traumatic brain injury, cervical cord injury, and those who survived <24 hours were excluded. A propensity score predicting statin use was created using logistic regression. Cox proportional hazard regression was then used to evaluate the effects of PIS use on mortality and the development of multiple organ failure (MOF, multiple organ dysfunction syndrome >5) and nosocomial infection (NI) after adjusting for important injury characteristics and the propensity of taking PISs. RESULTS Overall mortality and MOF rates for the study cohort (n = 295) were 21% and 50%, respectively. Over 24% of patients (n = 71) reported PIS use. Kaplan-Meier analysis revealed no difference in NI or mortality over time but did show a significant higher incidence of MOF in those with PIS use (p = 0.04). Regression analysis verified PIS was independently associated with an 80% higher risk of MOF (hazard ratio: 1.8; 95% confidence interval, 1.1-2.9) and was found to be one of the strongest independent risk factors for the development of MOF. CONCLUSION PIS use was independently associated with a higher risk of MOF postinjury. These results are contrary to previous analyses. The protective effect of statins may be lost in the severely injured, and modulation of the inflammatory response may result in higher morbidity. Further studies are required to better understand the impact and potential therapeutic utility of this commonly prescribed medication both before and after injury.

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Joseph P. Minei

University of Texas Southwestern Medical Center

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Jeffrey L. Johnson

University of Colorado Denver

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