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H Bryant Nguyen

Publications and source records attributed to H Bryant Nguyen.

12 recordsLinked to original sources
PubMed2006

Severe sepsis and septic shock: review of the literature and emergency department management guidelines.

Severe sepsis and septic shock are as common and lethal as other acute life-threatening conditions that emergency physicians routinely confront such as acute myocardial infarction, stroke, and trauma. Recent studies have led to a better understanding of the pathogenic mechanisms and the development of new or newly applied therapies. These therapies place early and aggressive management of severe sepsis and septic shock as integral to improving outcome. This independent review of the literature examines the recent pathogenic, diagnostic, and therapeutic advances in severe sepsis and septic shock for adults, with particular relevance to emergency practice. Recommendations are provided for therapies that have been shown to improve outcomes, including early goal-directed therapy, early and appropriate antimicrobials, source control, recombinant human activated protein C, corticosteroids, and low tidal volume mechanical ventilation.

Adrenal Cortex Hormones↗
PubMed2006

Interrater reliability of cardiac output measurements by transcutaneous Doppler ultrasound: implications for noninvasive hemodynamic monitoring in the ED.

INTRODUCTION: Hemodynamic monitoring is an important aspect of caring for the critically ill patients boarding in the emergency department (ED). The purpose of this study is to investigate the interrater agreement of noninvasive cardiac output measurements using transcutaneous Doppler ultrasound technique. METHODS: This is a prospective observational cohort study performed in a 32-bed adult ED of an academic tertiary center with approximately 65000 annual patient visits. Patients were enrolled after verbal consent over a 7-month period. The raters were ED personnel involved in patient care. Paired measurements of cardiac index (CI) and stroke volume index (SVI) were obtained from a transcutaneous Doppler ultrasound cardiac output monitor. RESULTS: A convenience sample of 107 (50 women and 57 men) patients with a median age of 49 (32, 62) years was enrolled. One hundred two paired measurements were performed in 91 patients in whom adequate Doppler ultrasound signals were obtainable. The raters included 35 emergency medicine attending physicians, 31 emergency medicine residents, 80 medical students, 47 nurses, and 11 emergency medical technicians. Cardiac index range was 0.6 to 5.3 L/min per square meter, and SVI range was 7.7 to 63.0 mL/m(2). The correlation of CI measurements between 2 raters was good (r(2) = 0.87; 95% confidence interval, 0.86-1.00; P < .001). Likewise, SVI measurements between 2 raters also showed acceptable correlation (r(2) = 0.84; 95% confidence interval, 0.81-0.96; P < .001). Interrater reliability was strong for CI (kappa = 0.83 with 92.2% agreement) and SVI measurements (kappa = 0.72 with 88.2% agreement). Most patients had an interrater difference below 10% in CI and SVI measurements. CONCLUSIONS: Emergency department personnel, regardless of their role in patient care, are able to obtain reliable cardiac output measurements in ED patients over a wide range of CI and SVI. Transcutaneous Doppler ultrasound technique may be an alternative to traditional invasive hemodynamic monitoring of critically ill patients presenting to the ED.

Adult↗
PubMed2006

Early goal-directed therapy in severe sepsis and septic shock revisited: concepts, controversies, and contemporary findings.

Studies of acute myocardial infarction, trauma, and stroke have been translated into improved outcomes by earlier diagnosis and application of therapy at the most proximal stage of hospital presentation. Most therapies for these diseases are instituted prior to admission to an ICU; this approach to the sepsis patient has been lacking. In response, a trial comparing early goal-directed therapy (EGDT) vs standard care was performed using specific criteria for the early identification of high-risk sepsis patients, verified definitions, and a consensus-derived protocol to reverse the hemodynamic perturbations of hypovolemia, vasoregulation, myocardial suppression, and increased metabolic demands. Five years after the EGDT publication, there has been much discussion generated with regard to the concepts of EGDT, as well as debate fueled regarding diagnostic and therapeutic interventions. However, during this time period further investigations by the primary investigators and others have brought additional contemporary findings. EGDT modulates some of the components of inflammation, as reflected by improved organ function. The end points used in the EGDT protocol, the outcome results, and the cost-effectiveness have subsequently been externally validated, revealing similar or even better findings than those from the original trial. Although EGDT is faced with challenges, a coordinated approach to sepsis management is necessary to duplicate the progress in outcomes seen in patients with conditions such as acute myocardial infarction, stroke, and trauma.

Algorithms↗
PubMed2005

Early goal-directed therapy, corticosteroid, and recombinant human activated protein C for the treatment of severe sepsis and septic shock in the emergency department.

OBJECTIVES: To describe our experience with early goal-directed therapy (EGDT), corticosteroid administration, and recombinant human activated protein C (rhAPC) administration in patients with severe sepsis or septic shock and an Acute Physiology and Chronic Health Evaluation (APACHE) II score > or =25 in the emergency department (ED). METHODS: This was a retrospective case series of a prospectively maintained ED sepsis registry. Data are presented as median (25th, 75th percentile). The setting was an academic tertiary ED with approximately 60,000 annual patient visits. Patients with severe sepsis or septic shock and an APACHE II score > or =25 entered in an ED sepsis registry over a four-month period were included. Patients who received rhAPC in the intensive care unit were excluded. Central venous catheterization for central venous pressure and central venous oxygen saturation monitoring, antibiotics, fluid resuscitation, mechanical ventilation, vasopressors, inotropes, corticosteroids, and rhAPC were initiated by the emergency physicians and continued in the intensive care unit by intensivists. RESULTS: Twenty-four patients were enrolled. Patient characteristics were as follows: age, 79.5 (68.0, 83.5) years; APACHE II score, 31.5 (29.8, 36.0); ED length of stay, 6.5 (4.0, 10.5) hours; predicted mortality, 76.7% (71.9, 86.4); and in-hospital mortality, 45.8%. All patients received broad-spectrum antibiotics, 54.2% completed EGDT, 33.3% received corticosteroids, and 33.3% received rhAPC. Time of antibiotic administration was 1.5 (1.0, 2.0) hours, time of central venous pressure/central venous oxygen saturation monitoring was 1.0 (0.5, 2.5) hour, and time of rhAPC administration was 9.5 (6.8, 10.5) hours after patients met criteria for severe sepsis or septic shock. In-hospital mortality of patients who received rhAPC in addition to other therapies was 25.0%. CONCLUSIONS: EGDT, corticosteroid administration, and rhAPC administration are feasible in the ED setting. While these evidence-based therapies individually have been shown to improve outcomes for patients with severe sepsis or septic shock, further studies are needed to examine their combined effectiveness during the early stages of this disease.

Adrenal Cortex Hormones↗
PubMed2005

Bench-to-bedside review: outcome predictions for critically ill patients in the emergency department.

The escalating number of emergency department (ED) visits, length of stay, and hospital overcrowding have been associated with an increasing number of critically ill patients cared for in the ED. Existing physiologic scoring systems have traditionally been used for outcome prediction, clinical research, quality of care analysis, and benchmarking in the intensive care unit (ICU) environment. However, there is limited experience with scoring systems in the ED, while early and aggressive intervention in critically ill patients in the ED is becoming increasingly important. Development and implementation of physiologic scoring systems specific to this setting is potentially useful in the early recognition and prognostication of illness severity. A few existing ICU physiologic scoring systems have been applied in the ED, with some success. Other ED specific scoring systems have been developed for various applications: recognition of patients at risk for infection; prediction of mortality after critical care transport; prediction of in-hospital mortality after admission; assessment of prehospital therapeutic efficacy; screening for severe acute respiratory syndrome; and prediction of pediatric hospital admission. Further efforts at developing unique physiologic assessment methodologies for use in the ED will improve quality of patient care, aid in resource allocation, improve prognostic accuracy, and objectively measure the impact of early intervention in the ED.

APACHE↗
PubMed2005

Central venous-arterial carbon dioxide difference as an indicator of cardiac index.

OBJECTIVE: The mixed venous-arterial (v-a) pCO(2) difference has been shown to be inversely correlated with the cardiac index (CI). A central venous pCO(2), which is easier to obtain, may provide similar information. The purpose of this study was to examine the correlation between the central venous-arterial pCO(2) difference and CI. DESIGN: Prospective, cohort study. SETTING: Intensive care unit of an urban tertiary care hospital. PATIENTS AND PARTICIPANTS: Eighty-three consecutive intensive care unit patients. MEASUREMENTS: Simultaneous blood gases from the arterial, pulmonary artery (PA), and central venous (CV) catheters were obtained. At the same time point, cardiac indices were measured by the thermodilution technique (an average of three measurements). The cardiac indices obtained by the venous-arterial differences were compared with those determined by thermodilution. RESULTS: The correlation (R(2)) between the mixed venous-arterial pCO(2) difference and cardiac index was 0.903 (p <0.0001), and the correlation between the central venous-arterial pCO(2) difference and cardiac index was 0.892 (p <0.0001). The regression equations for these relationships were natural log (CI)=1.837-0.159 (v-a) CO(2) for the PA and natural log (CI)=1.787-0.151 (v-a) CO(2) for the CV (p <0.0001 for both). The root-mean-squared error for the PA and CV regression equations were 0.095 and 0.101, respectively. CONCLUSION: Venous-arterial pCO(2) differences obtained from both the PA and CV circulations inversely correlate with the cardiac index. Substitution of a central for a mixed venous-arterial pCO(2) difference provides an accurate alternative method for calculation of cardiac output.

Adult↗
PubMed2004

Early lactate clearance is associated with improved outcome in severe sepsis and septic shock.

OBJECTIVE: Serial lactate concentrations can be used to examine disease severity in the intensive care unit. This study examines the clinical utility of the lactate clearance before intensive care unit admission (during the most proximal period of disease presentation) as an indicator of outcome in severe sepsis and septic shock. We hypothesize that a high lactate clearance in 6 hrs is associated with decreased mortality rate. DESIGN: Prospective observational study. SETTING: An urban emergency department and intensive care unit over a 1-yr period. PATIENTS: A convenience cohort of patients with severe sepsis or septic shock. INTERVENTIONS: Therapy was initiated in the emergency department and continued in the intensive care unit, including central venous and arterial catheterization, antibiotics, fluid resuscitation, mechanical ventilation, vasopressors, and inotropes when appropriate. MEASUREMENTS AND MAIN RESULTS: Vital signs, laboratory values, and Acute Physiology and Chronic Health Evaluation (APACHE) II score were obtained at hour 0 (emergency department presentation), hour 6, and over the first 72 hrs of hospitalization. Therapy given in the emergency department and intensive care unit was recorded. Lactate clearance was defined as the percent decrease in lactate from emergency department presentation to hour 6. Logistic regression analysis was performed to determine independent variables associated with mortality. One hundred and eleven patients were enrolled with mean age 64.9 +/- 16.7 yrs, emergency department length of stay 6.3 +/- 3.2 hrs, and overall in-hospital mortality rate 42.3%. Baseline APACHE II score was 20.2 +/- 6.8 and lactate 6.9 +/- 4.6 mmol/L. Survivors compared with nonsurvivors had a lactate clearance of 38.1 +/- 34.6 vs. 12.0 +/- 51.6%, respectively (p =.005). Multivariate logistic regression analysis of statistically significant univariate variables showed lactate clearance to have a significant inverse relationship with mortality (p =.04). There was an approximately 11% decrease likelihood of mortality for each 10% increase in lactate clearance. Patients with a lactate clearance> or =10%, relative to patients with a lactate clearance <10%, had a greater decrease in APACHE II score over the 72-hr study period and a lower 60-day mortality rate (p =.007). CONCLUSIONS: Lactate clearance early in the hospital course may indicate a resolution of global tissue hypoxia and is associated with decreased mortality rate. Patients with higher lactate clearance after 6 hrs of emergency department intervention have improved outcome compared with those with lower lactate clearance.

Biomarkers↗
PubMed2004

Prevalence of elevated troponin I in end-stage renal disease patients receiving hemodialysis.

OBJECTIVES: Patients with end-stage renal disease (ESRD) who are receiving hemodialysis have an increased incidence of atherosclerotic heart disease. Currently, there is considerable controversy regarding the significance of elevated cardiac troponin I (cTnI) levels in patients with ESRD. The objective of this study was to examine the prevalence of elevated cTnI levels in asymptomatic patients with ESRD on hemodialysis. METHODS: This was a prospective cohort study at an urban hospital outpatient dialysis center. Serum was collected pre- and postdialysis from patients on dialysis at this center over a two-week period. Samples were batched and analyzed for cTnI using the Asxym fluorescent antibody test. An elevated cTnI level was defined as >0.8 ng/dL. RESULTS: Predialysis cTnI levels ranged from <0.1 to 0.7 ng/dL, and postdialysis cTnI levels ranged from <0.1 to 0.6 ng/dL. None of the patients had a cTnI level >0.8 ng/dL. CONCLUSIONS: cTnI levels are not falsely elevated in patients with ESRD on hemodialysis. In a patient with ESRD, myocardial injury should be suspected if his or her cTnI level is >0.8 ng/dL.

Adult↗
PubMed2002

Critical care and emergency medicine.

The changing landscape of health care has resulted in an increase in the delivery of critical care in the emergency department. Although the emergency department duration is brief compared with the total length of hospitalization, physiologic determinants of outcome may be established before ICU admission. The care provided during the emergency department stay for critically ill patients has been shown to significantly impact the progression of organ failure and mortality. Despite these trends, formal critical care training for emergency physicians is limited. The need to maximize patient throughput in frequently overcrowded emergency departments hinders the provision of optimal care to the critically ill patient. Methodologies should be developed to examine the quality of patient care and objectively measure the impact of clinical interventions. The potential to improve outcome through educational initiatives and resource allocation should not be viewed as a burden of delivering a higher level of care in this setting but as a significant opportunity to effectively mitigate the socioeconomic consequences.

Critical Care↗