Boyoung Park

Emergency Department Occupancy Ratio is Associated With Increased Early Mortality

BACKGROUND To measure emergency department (ED) crowding, the emergency department occupancy ratio (EDOR) was introduced. OBJECTIVE Our aim was to determine whether the EDOR is associated with mortality in adult patients who visited the study hospital ED. METHODS We reviewed data on all patients who visited the ED of an urban tertiary academic hospital in Korea for 2 consecutive years. The EDOR is defined by the total number of patients in the ED divided by the number of licensed ED beds. We tested the association between the EDOR (quartile) and each outcome using a multivariable logistic regression analysis adjusted for potential confounders: age, sex, emergency medical services transport, transferred case, weekend visit, shift, triage acuity, visit cause of injury, operation, vital signs, intensive care unit or ward admission, and ED length of stay (quartile). The main outcome measures were survival status at discharge and at 1-7 days. RESULTS A total of 54,410 adult patients were enrolled. The EDOR ranged from 0.41 to 2.31 and the median was 1.24. On multivariable analyses, in comparison with the lowest (first) quartile, the highest (fourth) quartile of the EDOR was associated with 1-day mortality (adjusted odds ratio [OR] = 1.42; 95% confidence interval [CI] 1.08-1.88), 2-day mortality (adjusted OR = 1.31; 95% CI 1.04-1.67), and 3-day mortality (adjusted OR = 1.27; 95% CI 1.02-1.58). The EDOR was not significantly associated with 4- to 7-day mortalities and overall mortality at discharge. CONCLUSIONS The EDOR is associated with increased 1- to 3-day mortality even after controlling for potential confounders.

Validation of modified early warning score using serum lactate level in community-acquired pneumonia patients. The National Early Warning Score–Lactate score ☆ ☆☆ ★ ★★ ☆☆☆

STUDY OBJECTIVE The aim of this study was to investigate the prognostic prediction power of a newly introduced early warning score modified by serum lactate level, the National Early Warning Score-Lactate (NEWS-L) score, among community-acquired pneumonia (CAP) patients. We also compared the NEWS-L score with the pneumonia severity index (PSI) and CURB-65. METHODS We designed a retrospective observational study and collected data on confirmed adult CAP patients who visited the study hospital between October 2013 and September 2014. Variables relevant to, the NEWS-L score, PSI, and CURB-65 were extracted from electronic medical records. Survival status at hospital discharge was determined in the same manner. The NEWS-L score was calculated as NEWS-L=NEWS+serum lactate level (mmol/L). The NEWS-L was divided into quartiles. The ability to predict mortality was assessed through area under the receiver operating characteristic curve analysis and calibration analysis. RESULTS A total of 553 patients were enrolled, and the inpatient mortality rate was 10.8% (n=60). Mortality rates increased incrementally in conjunction with the NEWS-L quartiles: first quartile, 2.2%; second quartile, 7.9%; third quartile, 9.6%; and fourth quartile, 23.9%. The area under the receiver operating characteristic curve of the NEWS-L score was 0.73 (95% confidence interval [CI], 0.66-0.80), which showed no significant difference from that of the PSI (0.68; 95% CI, 0.61-0.76; P=.28) and CURB-65 (0.66; 95% CI, 0.59-0.73; P=.06). CONCLUSIONS The newly introduced early warning score modified by serum lactate level, NEWS-L score, was comparable to PSI and CURB-65, for predicting inpatient mortality among adult CAP patients.

Comparison of the trauma and injury severity score and modified early warning score with rapid lactate level (the ViEWS-L score) in blunt trauma patients

Objective The aim of this study was to compare the predictive value of the VitalPAC Early Warning Score-lactate (ViEWS-L) score with that of the trauma and injury severity score (TRISS), which is a pre-existing risk scoring system used in trauma patients. Methods The patients were blunt trauma victims admitted consecutively to the study hospital between 1 April 2010 and 31 March 2011, who were 15 years or older and had an injury severity score of 9 or higher. The lactate level, the ViEWS and revised trauma score upon arrival at the emergency department, and the injury severity score and TRISS were evaluated. The ViEWS-L score was calculated according to the formula: ViEWS-L=ViEWS+lactate (mmol/l). The ability to predict mortality was assessed by area under the receiver operating characteristic curve (AUC) analysis and calibration analysis. Results A total of 299 patients were available for analysis, of whom 33 died (11.0%). The median ViEWS-L score was 3.7 (interquartile range:1.8–6.4) and the median TRISS was 96.8 (interquartile range: 93.4–98.6). The ViEWS-L score was better than TRISS at predicting hospital mortality (AUC, 0.838; 95% confidence interval, 0.771–0.906 vs. AUC, 0.734; 95% confidence interval, 0.635–0.833, P=0.031). Calibration of the ViEWS-L score (&khgr;2=11.13, P=0.194) was good but that of TRISS was not (&khgr;2=16.97, P=0.018). Conclusion The prognostic value of the ViEWS-L score in terms of discrimination was better than that of TRISS in the blunt trauma patients admitted to the emergency department with an injury severity score of 9 or higher, and the ViEWS-L score showed good calibration.

Initial hyperlactatemia in the ED is associated with poor outcome in patients with ischemic stroke

BACKGROUND Hyperlactatemia may be associated with poor outcome in patients with ischemic stroke because it reflects a state of tissue perfusion. This study aims to know whether initial hyperlactatemia in the emergency department (ED) is associated with poor outcome in patients with ischemic stroke. METHODS A retrospective observational study was performed in an urban tertiary hospital ED. Patients with an admission diagnosis of ischemic stroke were consecutively enrolled between April 1, 2010, and March 31, 2011. Lactate and glucose levels were obtained at the time of presentation to the ED, whereas the National Institutes of Health Stroke Scale score was assessed at the time of admission. Poor outcome was defined as a modified Rankin scale score greater than or equal to 2 at 3 months. The survival status at 3 months was also obtained. Hyperlactatemia was defined by lactate levels greater than 2 mmol/L. RESULTS A total of 292 patients were enrolled. At 3 months after stroke, 183 (62.7%) were considered to have poor outcomes, whereas 16 (5.5%) had died. Seventy (24.0%) had initial hyperlactatemia. Multivariable logistic regression analysis showed that hyperlactatemia was independently associated with a higher risk of poor outcome at 3 months (adjusted odd ratio, 2.15; 95% confidence interval, 1.06-4.37; P=.035) and a trend to death at 3 months (adjusted odd ratio, 4.31; 95% confidence interval, 0.91-20.56; P=.066). CONCLUSIONS Among patients with ischemic stroke, initial hyperlactatemia represents an independent risk factor for poor outcome after controlling for stroke severity, risk factors, initial glucose level, and interval from onset of stroke symptoms to ED arrival.

Initial serum lactate level is associated with inpatient mortality in patients with community-acquired pneumonia ☆ ☆☆ ★

STUDY OBJECTIVE The aim of the present study was to investigate the prognostic value of the initial serum lactate level in patients with community-acquired pneumonia (CAP). METHODS We collected data on hospitalized adult patients with CAP via the study hospital emergency department between October 2012 and September 2013. Demographics, comorbidities, and physiologic and laboratory variables including initial C-reactive protein (CRP) and serum lactate level were extracted from the electronic medical record. The primary outcome was inpatient mortality. Comparisons between survivors and nonsurvivors were performed, and multivariable logistic regression analyses were constructed as dependent variables of both continuous and categorical varieties. RESULTS A total of 397 patients were enrolled, and the mortality cases were 46 (11.6%). The mean lactate level was 1.7 ± 1.4 mmol/L and was significantly higher in the nonsurvivor group than in the survivor group (2.4 ± 2.2 mmol/L vs 1.6 ± 1.2 mmol/L). In the multivariable logistic regression model for inpatient mortality constructed using lactate, CRP, and laboratory variables of pneumonia severity index (PSI), lactate and CRP remained as significant factors, but laboratory variables of PSI were not. In other multivariable logistic regression models for the outcome constructed using collected laboratory variables and PSI, lactate remained as a significant factor (adjusted odds ratio, 1.24; 95% confidence interval, 1.01-1.53; P = .042 by continuous variable; adjusted odds ratio of third tertile, 2.60; 95% confidence interval, 1.02-6.66; P = .046 by category variable). C-reactive protein and albumin were also left as significant factors. CONCLUSIONS The initial serum lactate level is independently associated with mortality in hospitalized patients with CAP. However, laboratory variables of PSI or others were not, except CRP and albumin.

ED crowding is associated with inpatient mortality among critically ill patients admitted via the ED: post hoc analysis from a retrospective study ☆,☆☆,★

BACKGROUND Adverse effects of emergency department (ED) crowding among critically ill patients are not well known. OBJECTIVES We evaluated the association between ED crowding and inpatient mortality among critically ill patients admitted via the ED, and analyzed subsets of patients according to admission diagnosis. METHODS We performed a post hoc analysis using data from a previous retrospective study. We enrolled admitted patients via the ED with an initial systolic blood pressure of 90 mm Hg or lower when presenting to the ED. The ED occupancy ratio was used as a measure of crowding. The primary outcome was inpatient mortality. Multivariable logistic regression models adjusted for potential confounding variables were constructed for the entire cohort and for subsets according to admission diagnosis (infection, cardiac and vascular disease, trauma, gastrointestinal bleeding, and other factors). RESULTS A total of 1801 patients were enrolled, with a mortality rate of 14.6% (262 patients). The mortality rate by ED occupancy ratio quartile was 9.7% for the first quartile, 15.9% for the second quartile, 18.2% for the third quartile, and 14.4% for the fourth quartile. This resulted in adjusted odds ratios of 1.95, 2.51, and 1.93 and corresponding 95% confidence intervals of 1.23-3.12, 1.58-3.99, and 1.21-3.09 for the second, third, and fourth quartiles, respectively, compared with the first quartile. The effect of ED crowding was highest in the trauma subset, followed by the infection subset, whereas ED crowding did not appear to have any effect on the cardiac and vascular disease subsets. CONCLUSION Emergency department crowding was associated with increased inpatient mortality among critically ill patients admitted via the ED.

Predictive value of the National Early Warning Score–Lactate for mortality and the need for critical care among general emergency department patients ☆ ☆☆ ★

STUDY OBJECTIVES What is the predictive value of the National Early Warning Score-Lactate (NEWS-L) score for mortality and the need for critical care in general emergency department (ED) patients? METHODS In this retrospective cohort study, we enrolled all adult patients who visited the ED of an urban academic tertiary-care university hospital in South Korea over 2 consecutive months. The primary outcome was 2-day mortality. The secondary outcomes were the need for critical care (advanced airway use, vasopressor or inotropic agent use, intensive care unit admission) during an ED stay; 2-day composite outcome (2-day mortality and the need for critical care); 7-day mortality; and in-hospital mortality. RESULTS During the study period, 4624 adult patients visited the ED. Of these, 87 (1.9%) died within 2 days. In total, 481 patients (10.4%) required critical care during their ED stay. The 2-day composite outcome, 7-day mortality, and in-hospital mortality were 10.9% (503/4624), 2.5% (116/4624), and 3.9% (182/4624), respectively. The NEWS-L demonstrated excellent predictive value for 2-day mortality with an area under the receiver operating characteristic curve (AUROC) of 0.96 (95% confidence interval [CI], 0.94-0.98); this value was better than that of the NEWS alone (AUROC 0.94 [95% CI, 0.91-0.96], P=.002). The AUROC of the NEWS-L for the need for critical care was 0.83 (95% CI, 0.81-0.85); for the 2-day composite outcome, it was 0.84 (95% CI, 0.82-0.86); for 7-day mortality, it was 0.94 (95% CI, 0.92-0.96); and for in-hospital mortality, it was 0.87 (95% CI, 0.85-0.90). Logistic regression results confirmed that the ratio of the NEWS to the initial lactate level was 1:1. Similar results were obtained in the subgroup analyses (disease-infection, disease-vascular and heart, disease-others, and nondisease). The high-risk NEWS-L group (NEWS-L≥7, 9.4% of all patients) had an adjusted odds ratio of 28.67 (12.66-64.92) for 2-day mortality in the logistic regression model adjusted for basic characteristics. CONCLUSION The NEWS-L can provide excellent discriminant value for predicting 2-day mortality in general ED patients, and it has the best discriminant value regarding the need for critical care and composite outcomes. The NEWS-L may be helpful in the early identification of at-risk general ED patients.

Diagnostic performance of initial serum albumin level for predicting in-hospital mortality among aspiration pneumonia patients

Purpose: The predictive value of serum albumin in adult aspiration pneumonia patients remains unknown. Methods: Using data collected during a 3‐year retrospective cohort of hospitalized adult patients with aspiration pneumonia, we evaluated the predictive value of serum albumin level at ED presentation for in‐hospital mortality. Results: 248 Patients were enrolled; of these, 51 cases died (20.6%). The mean serum albumin level was 3.4 ± 0.7 g/dL and serum albumin levels were significantly lower in the non‐survivor group than in the survivor group (3.0 ± 0.6 g/dL vs. 3.5 ± 0.6 g/dL). In the multivariable logistic regression model, albumin was associated with in‐hospital mortality significantly (adjusted odds ratio 0.30, 95% confidential interval (CI) 0.16–0.57). The area under the receiver operating characteristics (AUROC) for in‐hospital survival was 0.72 (95% CI 0.64–0.80). The Youden index was 3.2 g/dL and corresponding sensitivity, specificity, positive predictive value, negative predictive value, positive and negative likelihood ratio were 68.6%, 66.5%, 34.7%, 89.1%, 2.05 and 0.47, respectively. High sensitivity (98.0%) was shown at albumin level of 4.0 g/dL and high specificity (94.9%) was shown at level of 2.5 g/dL. Conclusion: Initial serum albumin levels were independently associated with in‐hospital mortality among adult patients hospitalized with aspiration pneumonia and demonstrated fair discriminative performance in the prediction of in‐hospital mortality.

Diagnostic performance of initial serum lactate for predicting bacteremia in female patients with acute pyelonephritis

OBJECTIVES The purpose of the present study was to investigate the diagnostic value of lactate for predicting bacteremia in female patients with acute pyelonephritis (APN). METHODS We conducted a retrospective study of female patients with APN who visited the study hospital emergency department. The demographics, comorbidities, physiologies, and laboratory variables including white blood cell count and segmented neutrophil count, C-reactive protein, and initial serum lactate levels were collected and analyzed to identify associations with the presence of bacteremia. RESULTS During the study period, a total of 314 patients were enrolled. One hundred twenty-three patients (39.2%) had bacteremia. Escherichia coli was the most frequent pathogen. Logistic regression analysis demonstrated that the lactate level was independently associated with the presence of bacteremia (odds ratio, 1.39 [95% confidence interval, 1.08-1.78]). The C-statistic of the lactate level was 0.67 (95% CI, 0.60-0.73). At a cutoff value of 1.4mmol/L, the lactate level predicted bacteremia with a sensitivity (53.7%), specificity (72.3%), positive predictive value (55.5%), negative predictive value (70.8%), positive likelihood ratio (1.93), and negative likelihood ratio (0.64). CONCLUSION The initial serum lactate level showed poor discriminative performance for predicting bacteremia in female patients with APN.

Comprehensive interpretation of hyperglycemia and hyperosmolality on the clinical outcomes among ischemic stroke patients

BACKGROUND Hyperglycemia and hyperosmolality are associated with poor outcomes among acute ischemic stroke (AIS) patients. OBJECTIVES We evaluated the association between hyperglycemia and hyperosmolality, as a combination measure, with poor outcome among AIS patients. METHODS We conducted a retrospective study of AIS patients admitted to the study hospital emergency department between January and December 2014. Hyperglycemia was defined as serum glucose >144 mg/dL, and hyperosmolality was defined as a serum osmolality >295 mOsm/kg. After excluding hypoglycemia and hypoosmolality, the enrolled patients were classified into the following 4 subgroups: normoglycemia-normoosmolality, hyperglycemia-normoosmolality (HGNO), normoglycemia-hyperosmolality (NGHO), and hyperglycemia-normoosmolality (HGHO). The primary outcome was poor neurological status at 6 months, which was defined as a modified Rankin scale score ≥2. RESULTS Six hundred seven patients were included. The primary outcome was 336 (55.4%), and it was highest in the HGNO group (69.6%, 103/148), followed by the HGHO group (67.9%, 53/78), the NGHO group (57.3%, 43/75) and the normoglycemia-normoosmolality group (44.7%, 137/306). The multivariable logistic regression analysis revealed that HGNO and HGHO remained significant factors, with primary outcomes (adjusted odds ratio, 2.08; 95% confidence interval, 1.16-3.71) and 2.93 (1.45-5.91), respectively), whereas NGHO was not a significant factor. Cases of extremely high sodium levels were few in the NGHO and HGHO groups, whereas considerable cases of extremely high glucose level were observed in the HGHO group. CONCLUSION Hyperglycemia was associated with poor outcome, even after excluding the effect of hyperosmolality. However, hyperosmolality without hyperglycemia was not associated with poor outcome. An additive effect, likely reflecting severe hyperglycemia, was observed.