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ABSTRACT: Sonographic measurement of the inferior vena cava (IVC) caval index predicts central venous pressure in ED patients. Fluid responsiveness (FR) is a measure of preload dependence defined as an increase in cardiac output secondary to volume expansion. We sought to determine if the caval index is an accurate measurement of FR in ED patients.
We conducted a prospective, observational trial at an urban, academic, adult ED with an annual census >105 000. Included patients were clinically suspected of eu- and hypovolemia. Excluded patients were <18 years old, pregnant, incarcerated, sustained significant trauma or unable to consent. Supine IVC diameter was measured by bedside ultrasonography (M-Turbo; Sonosite, Bothwell, WA, USA). Caval index = [(expiratory IVC diameter - inspiratory IVC diameter)/expiratory IVC diameter] × 100. FR was defined as an increase in the cardiac index by >10% by impedance cardiography (BioZ; Sonosite) following passive leg raise. The primary outcome was analysed using Spearman correlations for non-parametric data and the area under the receiver operating characteristics curve by Wilcoxon method.
Thirty patients were enrolled; four were excluded because of incomplete data collection. Thirty-one per cent (95% CI 13-48) of the patients were FR. The mean initial caval and cardiac index were 15.8% (95% CI 9.5-22) and 2.9 L/min/m(2) (95% CI 2.6-3.2), respectively. Caval index did not predict FR (receiver operating curve = 0.46, 95% CI 0.21-0.71, P = 0.63).
Bedside sonographic measurement of IVC caval index does not predict FR in a heterogeneous ED patient population. Further research using this technique in targeted patient subsets and a variety of shock etiologies is needed.
Emergency medicine Australasia: EMA 10/2012; 24(5):534-9. · 0.98 Impact Factor
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ABSTRACT: BACKGROUND: The ability to accurately assess the level of immunosuppression in HIV+ patients in the emergency department (ED) is often limited and can affect management of these patients. OBJECTIVE: To evaluate the relationship between the absolute lymphocyte count (ALC) and CD4 count in HIV patients admitted through the ED with pneumonia and how utilization of this relationship may affect early consideration and evaluation of Pneumocystis jiroveci pneumonia (PCP). METHODS: Retrospective multicenter 5-year study of HIV+ patients with an ICD-9 diagnosis of pneumonia. Included patients had an ALC measured on ED presentation and a CD4 count measured in < 24 h. A receiver operator curve (ROC), decision plot analysis, and McNemar test of proportions were used to characterize the relationship between study variables. RESULTS: Six hundred eighty six patients were enrolled, 23.2% (95% confidence interval [CI] 20.2-26.1) were diagnosed with PCP. The geometric mean CD4 count and ALC were 81 and 1089, respectively. The correlation between ALC and CD4 was r = 0.60 (95% CI 0.55-65, p < 0.01). The ROC was 0.78 (0.75-0.82). An ALC < 1700 cells/mm(3) had a sensitivity of 84% (95% CI 80-87) and specificity of 55% (95% CI 48-70) for a CD4 < 200 cells/mm(3). An ALC threshold of 1700 cells/mm(3) would have identified 86% of patients with PCP but falsely identified 2.5 patients without PCP for every one accurately identified. CONCLUSION: The ALC threshold of 1700 cells/mm(3) retains significant discriminatory value and would moderately improve identification of patients with a CD4 < 200 cells/mm(3) but is not likely to be reliable as the sole method of early recognition and evaluation of PCP.
Journal of Emergency Medicine 07/2012; · 1.31 Impact Factor
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Anthony M Napoli
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ABSTRACT: Clinical assessment and vital signs are poor predictors of the overall hemodynamic state. Optimal measurement of the response to fluid resuscitation and hemodynamics has previously required invasive measurement with radial and pulmonary artery catheterization. Newer noninvasive resuscitation technology offers the hope of more accurately and safely monitoring a broader range of critically ill patients while using fewer resources. Fluid responsiveness, the cardiac response to volume loading, represents a dynamic method of improving upon the assessment of preload when compared to static measures like central venous pressure. Multiple new hemodynamic monitors now exist that can noninvasively report cardiac output and oxygen delivery in a continuous manner. Proper assessment of the potential future role of these techniques in resuscitation requires understanding the underlying physiologic and clinical principles, reviewing the most recent literature examining their clinical validity, and evaluating their respective advantages and limitations.
Cardiology research and practice. 01/2012; 2012:531908.
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ABSTRACT: Exocytosis of granules containing the cytolytic effector (CE) molecules granzyme A (GzmA), granzyme B (GzmB), and perforin is one major pathway of lymphocyte-mediated cytotoxicity. Studies in murine models and the finding of elevated granzyme levels in the plasma of septic patients have implicated cytotoxic lymphocytes in the pathogenesis of sepsis. We sought to evaluate the role of cytotoxic cells and CE in sepsis and determine if intracellular levels of CE in cytotoxic cells correlate with disease severity. We conducted a prospective cohort study of 40 patients enrolled into one of three groups: controls (C), acutely ill nonseptic illnesses, or patients with severe sepsis (SS) (lactate, >4 mmol/L; systolic blood pressure, <90 mmHg after 2 L normal saline). Peripheral blood mononuclear cells were isolated and stained for extracellular markers for defined subpopulations and for intracellular expression of GzmA and GzmB and perforin. Levels of CE were quantified by geometric mean fluorescent intensity (GMFI) via flow cytometry. Cytotoxic T lymphocyte (CTL) expression was higher in SS (P = 0.04). The GMFI of GzmB was significantly higher in CTLs of SS patients versus acutely ill nonseptic illnesses or C. The GMFI of each GzmA and GzmB in CTLs were associated with the Acute Physiology and Chronic Health Evaluation II score (P = 0.01). A significant increase in the number of granulocytes in the peripheral blood mononuclear cells of SS patients consisted primarily of low-density neutrophils, which expressed increased levels of GzmA (P < 0.01). The results suggest that CTLs are activated in SS and express significantly higher intracellular levels of GzmB and that GzmA and B levels correlate with disease severity.
Shock (Augusta, Ga.) 11/2011; 37(3):257-62. · 2.87 Impact Factor
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ABSTRACT: The sepsis resuscitation bundle is the result of an effort on behalf of the Surviving Sepsis Campaign and the Institute for Healthcare Improvement to translate individual guideline recommendations into standardized, achievable goals for physicians caring for the critically ill patient. Implementation of this bundle is associated with decreased mortality. Many of the bundle items reflect components of therapy shown to improve mortality in the seminal early goal-directed therapy trial for severe sepsis and septic shock, including an initial lactate measurement. Elevations in serum lactate are associated with increased mortality, and may result from either increased lactate production or impaired lactate clearance. Lactate clearance may be an important addition to the monitoring and management bundles of patients with severe sepsis and septic shock, However, specific mechanisms of lactate clearance, the relation of lactate clearance to traditional hemodynamic parameters, and the importance of lactate clearance as a therapeutic target or monitoring tool remain unclear.
Critical care (London, England) 10/2011; 15(5):199. · 4.61 Impact Factor
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ABSTRACT: To evaluate the interrater reliability and parallel forms reliability of transcutaneous Doppler ultrasonography (TCDU) and impedance cardiography (ICG) in clinically and hemodynamically stable emergency department patients.
We enrolled 30 emergency department patients over a 2-day period. Patients had three consecutive simultaneously blinded measurements of stroke volume (SV) and heart rate (HR) recorded by TCDU (USCOM) and ICG (Cardiodynamics). Two physicians, with basic familiarity but no clinical experience with either device recorded three measurements of SV and HR on each device. Intraclass correlation coefficients (ICC), mixed linear models for repeated measures, and Bland-Altman plots were used to assess interrater reliability and nature of relationships between measures from the devices (parallel forms reliability).
The ICC for TCDU was 0.96 for HR and 0.95 for SV, whereas the ICC for ICG was 0.93 for HR and 0.98 for SV. The device HR estimates were significantly related (P<0.0001 for all slopes) for all phases, but SV failed to reach significance following the first 50 trials [t(94.2)=2.72, P=0.0077]. Although HR estimates were within reasonable clinical tolerances (bias 0.5%, limits of agreement -15.4 to 16.4%) SV disagreement was concerning (bias 3.8%, limits of agreement -58 to 66%).
Both TCDU and ICG have fair interrater reliability of SV independent of operator experience. A statistically significant relationship exists between the two devices but this does not produce predictable values in SV. Over time comparative results become less biased but remain limited by a great degree of variability.
European journal of emergency medicine: official journal of the European Society for Emergency Medicine 10/2011; 19(5):297-303. · 0.73 Impact Factor
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Critical care medicine 04/2011; 39(4):888-9. · 6.37 Impact Factor
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ABSTRACT: This study sought to determine if the automated absolute lymphocyte count (ALC) predicts a "low" (<200 × 10(6) cells/μL) CD4 count in patients with known human immunodeficiency virus (HIV+) who are admitted to the hospital from the emergency department (ED).
This retrospective cohort study over an 8-year period was performed in a single, urban academic tertiary care hospital with over 85,000 annual ED visits. Included were patients who were known to be HIV+ and admitted from the ED, who had an ALC measured in the ED and a CD4 count measured within 24 hours of admission. Back-translated means and confidence intervals (CIs) were used to describe CD4 and ALC levels. The primary outcome was to determine the utility of an ALC threshold for predicting a CD4 count of <200 × 10(6) cells/μL by assessing the strength of association between log-transformed ALC and CD4 counts using a Pearson correlation coefficient. In addition, area under the receiver operator curve (AUC) and a decision plot analysis were used to calculate the sensitivity, specificity, and the positive and negative likelihood ratios to identify prespecified optimal clinical thresholds of a likelihood ratio of <0.1 and >10.
A total of 866 patients (mean age 42 years, 40% female) met inclusion criteria. The transformed means (95% CIs) for CD4 and ALC were 34 (31-38) and 654 (618-691), respectively. There was a significant relationship between the two measures, r = 0.74 (95% CI = 0.71 to 0.77, p < 0.01). The AUC was 0.92 (95% CI = 0.90 to 0.94, p < 0.001). An ALC of <1700 × 10(6) cells/μL had a sensitivity of 95% (95% CI = 93% to 96%), specificity of 52% (95% CI = 43% to 62%), and negative likelihood ratio of 0.09 (95% CI = 0.05 to 0.2) for a CD4 count of <200 × 10(6) cells/μL. An ALC of <950 × 10(6) cells/μL has a sensitivity of 76% (95% CI = 73% to 79%), specificity of 93% (95% CI = 87% to 96%), and positive likelihood ratio of 10.1 (95% CI = 8.2 to 14) for a CD4 count of <200 × 10(6) cells/μL.
Absolute lymphocyte count was predictive of a CD4 count of <200 × 10(6) cells/μL in HIV+ patients who present to the ED, necessitating hospital admission. A CD4 count of <200 × 10(6) cells/μL is very likely if the ED ALC is <950 × 10(6) cells/μL and less likely if the ALC is >1,700 × 10(6) cells/μL. Depending on pretest probability, clinical use of this relationship may help emergency physicians predict the likelihood of susceptibility to opportunistic infections and may help identify patients who should receive definitive CD4 testing.
Academic Emergency Medicine 04/2011; 18(4):385-9. · 1.86 Impact Factor
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ABSTRACT: Reversible ventricular dysfunction is common in sepsis. Impedance cardiography allows for noninvasive measurement of contractility through time interval or amplitude-based measures. This study evaluates the prognostic capacity of these measures in patients with severe sepsis or septic shock in the emergency department.
This is a prospective observational cohort study of 56 patients older than 18 years meeting criteria for early goal-directed therapy (lactate level >4 mmol/L or systolic blood pressure <90 mm Hg after 2-L isotonic sodium chloride solution). Continuous collections of contractility measures were performed, and patients were followed until discharge or in-hospital death.
A significant 57% reduction in the accelerated contractility index (ACI) in nonsurvivors (71 1/s(2) [41-102]) compared with survivors (123 1/s(2) [98-147]) existed. Only ACI predicted in-hospital mortality (area under the receiver operating characteristic curve = 0.70, P < .01). Accelerated contractility index did not correlate with amount of prior fluid administration, central venous pressure, number of cardiac risk factors, or troponin I value. An ACI of less than 40 1/s(2) is 95% (84-99) specific with a positive likelihood ratio of 8.8 for predicting in-hospital mortality.
A reduced ACI is associated with mortality in critically ill emergency department patients presenting with severe sepsis and septic shock meeting criteria for early goal-directed therapy. This association appears to be independent of clinical or laboratory predictors of cardiac dysfunction or preload.
Journal of critical care 02/2011; 26(1):47-53. · 2.13 Impact Factor
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The American journal of cardiology 06/2010; 105(11):1648; author reply 1647-8. · 3.58 Impact Factor
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ABSTRACT: This study sought to determine whether tissue oxygenation (StO(2)) could be used as a surrogate for central venous oxygenation (ScVO(2)) in early goal-directed therapy (EGDT).
The study enrolled a prospective convenience sample of patients aged > or =18 years with sepsis and systolic blood pressure <90 mm Hg after 2 L of normal saline or lactate >4 mmol, who received a continuous central venous oximetry catheter. StO(2) and ScVO(2) were measured at 15-minute intervals. Data were analyzed using a random coefficients model, correlations, and Bland-Altman plots.
There were 284 measurements in 40 patients. While a statistically significant relationship existed between StO(2) and ScVO(2) (F(1,37) = 10.23, p = 0.002), StO(2) appears to systematically overestimate at lower ScVO(2) and underestimate at higher ScVO(2). This was reflected in the fixed effect slope of 0.49 (95% confidence interval [CI] = 0.266 to 0.720) and intercept of 34 (95% CI = 14.681 to 50.830), which were significantly different from 1 and 0, respectively. The initial point correlation (r = 0.5) was fair, but there was poor overall agreement (bias = 4.3, limits of agreement = -20.8 to 29.4).
Correlation between StO(2) and ScVO(2) was fair. The two measures trend in the same direction, but clinical use of StO(2) in lieu of ScVO(2) is unsubstantiated due to large and systematic biases. However, these biases may reflect real physiologic states. Further research may investigate if these measures could be used in concert as prognostic indicators.
Academic Emergency Medicine 04/2010; 17(4):349-52. · 1.86 Impact Factor
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ABSTRACT: Pulmonary artery catheterization poses significant risks and requires specialized training. Technological advances allow for more readily available, noninvasive clinical measurements of hemodynamics. Few studies exist that assess the efficacy of noninvasive hemodynamic monitoring in sepsis patients. The authors hypothesized that cardiac index, as measured noninvasively by impedance cardiography (ICG) in emergency department (ED) patients undergoing early goal-directed therapy (EGDT) for sepsis, would be associated with in-hospital mortality.
This was a prospective observational cohort study of patients age over 18 years meeting criteria for EGDT (lactate > 4 or systolic blood pressure < 90 after 2 L of normal saline). Initial measurements of cardiac index were obtained by ICG. Patients were followed throughout their hospital course until discharge or in-hospital death. Cardiac index measures in survivors and nonsurvivors are presented as means and 95% confidence intervals (CI). Diagnostic performance of ICG in predicting mortality was tested by receiver operating characteristic (ROC) curve and areas under the ROC curves (AUC) were compared using Wilcoxon test.
Fifty-six patients were enrolled; one was excluded due to an inability to complete data acquisition. The mean cardiac index in nonsurvivors (2.3 L/min.m(2), 95% CI = 1.6 to 3.0) was less than that for survivors (3.2, 95% CI = 2.9 to 3.5) with mean difference of 0.9 (95% CI = 0.12 to 1.71). The AUC for ICG in predicting mortality was 0.71 (95% CI = 0.58 to 0.88; p = 0.004). A cardiac index of < 2 L/min.m(2) had a sensitivity of 43% (95% CI = 18% to 71%), specificity of 93% (95% CI = 80% to 95%), positive likelihood ratio of 5.9, and negative likelihood ratio of 0.6 for predicting in-hospital mortality.
Early, noninvasive measurement of the cardiac index in critically ill severe sepsis and septic shock patients can be performed in the ED for those who meet criteria for EGDT. There appears to be an association between an initial lower cardiac index as measured noninvasively and in-hospital mortality.
Academic Emergency Medicine 04/2010; 17(4):452-5. · 1.86 Impact Factor
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ABSTRACT: Previous analyses of physiologic parameter changes during ascent to altitude have incorporated small numbers of well-trained climbers. The effects of altitude illness are more likely to occur and may come to medical attention more frequently in unacclimatized recreational individuals. We sought to evaluate acute changes in physiologic parameters during ascent to high altitude (14,100 ft) in recreational climbers.
We performed a prospective naturalistic study of 221 recreational climbers at Mount Shasta (peak altitude of 14,162 ft). Baseline vital signs were recorded at 3500 ft (blood pressure, heart rate, respiratory rate, pulse oximetry, and peak flow). Subsequent measurements were obtained at 6700 ft, 10,400 ft, and at the summit. Mean vital signs and the amount they changed with altitude were estimated using mixed linear models.
One hundred twenty-five climbers (56.6%) reached the summit. Heart rate increased and pulse oximetry decreased with ascent (mean, 71.9, 79, 97, and 102.4 beats/min and 96.9%, 93.9%, 88.8%, and 80.8%, respectively), with estimates at each altitude differing statistically at P < .0001. Mean systolic and diastolic blood pressures varied significantly by altitude (not measured at summit), but the changes were not monotonic. Peak flow progressively declined with ascent, but the difference between 6700 and 10,400 was not statistically significant. Respiratory rate did not change significantly.
Acute compensation for altitude-induced hypoxia involves numerous physiologic changes; this is supported by our data that demonstrate significant changes in blood pressure and stepwise changes in pulse oximetry, peak flow, and heart rate. Consideration of these changes can be incorporated in future studies of the affect of altitude on recreational climbers.
The American journal of emergency medicine 11/2009; 27(9):1081-4. · 1.54 Impact Factor
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ABSTRACT: The proliferation of research, particularly research into evidence-based care and quality improvement, has brought about a void in the need to educate, summarize, and distill scientific advances. Clinical policies or practice guidelines are a unique method of filling this void. While the number of policies published has increased significantly over the last 10 years, their impact on physician practice remains ill-defined. This article aims to provide historical background and methodology, explore physician attitudes toward them and their effectiveness at impacting clinical care, as well as discuss their future medical legal implications.
Journal of Emergency Medicine 12/2007; 33(4):425-32. · 1.31 Impact Factor
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ABSTRACT: Facial nerve paralysis (Cranial Nerve VII, CN VII) can be a disfiguring disorder with profound impact upon the patient. The etiology of facial nerve paralysis may be congenital, iatrogenic, or result from neoplasm, infection, trauma, or toxic exposure. In the emergency department, the most common cause of unilateral facial paralysis is Bell's palsy, also known as idiopathic facial paralysis (IFP). We report a case of delayed presentation of unilateral facial nerve paralysis 3 days after sustaining a traumatic head injury. Re-evaluation and imaging of this patient revealed a full facial paralysis and temporal bone fracture extending into the facial canal. Because cranial nerve injuries occur in approximately 5-10% of head-injured patients, a good history and physical examination is important to differentiate IFP from another etiology. Newer generation high-resolution computed tomography (CT) scans are commonly demonstrating these fractures. An understanding of this complication, appropriate patient follow-up, and early involvement of the Otolaryngologist is important in management of these patients. The mechanism as well as the timing of facial nerve paralysis will determine the proper evaluation, consultation, and management for the patient. Patients with total or immediate paralysis as well as those with poorly prognostic audiogram results are good candidates for surgical repair.
Journal of Emergency Medicine 12/2005; 29(4):421-4. · 1.31 Impact Factor
