Bernstein Steven L, Verghese Vinu, Leung Winifred, Lunney Anne T, Perez Ivelisse
Department of Emergency Medicine, Newark Beth Israel Medical Center, St. Barnabas Health Care System, Newark, NJ, USA.
Acad Emerg Med. 2003 Sep;10(9):938-42. doi: 10.1111/j.1553-2712.2003.tb00647.x.
To develop a quantitative measure of emergency department (ED) crowding and busyness.
A five-week study in spring 2002 in an urban teaching ED compared a new index (the Emergency Department Work Index [EDWIN]) with attending physician and nurse ratings of crowding. EDWIN is defined as summation operator n(i)t(i)/N(a)(B(T)-B(A)), where n(i) = number of patients in the ED in triage category i, t(i) = triage category, N(a) = number of attending physicians on duty, B(T) = number of treatment bays, and B(A) = number of admitted patients in the ED. The triage system used is the Emergency Severity Index (ESI), which was modified by reversing the ranking of triage categories; that is, an ESI score of 1 represented the least acute patient and 5 the sickest. EDWIN was calculated every two hours in a convenience sample of 60 eight-hour shifts. With each measurement, the charge attending physician and nurse estimated how busy/crowded the ED was, using a Likert scale. Nurse and physician assessments were averaged and compared with EDWIN scores. Data were analyzed with SPSS 10.0 (SPSS Inc., Chicago, IL).
A total of 2,647 patients aged 18 years and older were assessed at 225 time points over 35 consecutive days. Nurses and physicians showed good interrater agreement of crowding assessment (weighted kappa 0.61, 95% confidence interval = 0.53 to 0.69). Median EDWIN scores and interquartile ranges (IQRs) when the ED was rated as not busy, average, and very busy were 1.07 (IQR = 0.80 to 1.55), 1.55 (IQR = 1.16 to 1.93), and 1.83 (IQR = 1.42 to 2.45) (p < 0.001). The ED was on diversion for 17 time blocks (6.5% of all blocks), with a median EDWIN of 2.77 (IQR = 1.83 to 3.63), compared with an EDWIN of 1.45 (IQR = 1.05 to 2.00) when not on diversion (p < 0.001). EDWIN scores correlated weakly with various process-of-care measures chosen as secondary end points.
EDWIN correlated well with staff assessment of ED crowding and diversion. The index can be programmed into tracking software for use as a "dashboard" to alert staff when the ED is approaching crisis. If validated across other sites, EDWIN may provide a tool to compare crowding levels among different EDs.
构建一种急诊科拥挤和繁忙程度的量化指标。
2002年春季在一家城市教学医院急诊科进行了为期五周的研究，将一种新指标（急诊科工作指数[EDWIN]）与主治医师和护士对拥挤程度的评分进行比较。EDWIN的定义为求和运算符n(i)t(i)/N(a)(B(T)-B(A))，其中n(i)为处于分诊类别i的急诊科患者数量，t(i)为分诊类别，N(a)为值班主治医师数量，B(T)为治疗床位数量，B(A)为急诊科收治患者数量。所使用的分诊系统是急诊严重程度指数（ESI），通过颠倒分诊类别的排名进行了修改；即，ESI评分为1表示病情最不危急的患者，评分为5表示病情最危急的患者。在60个八小时轮班的便利样本中，每两小时计算一次EDWIN。每次测量时，负责主治医师和护士使用李克特量表估计急诊科的繁忙/拥挤程度。护士和医师的评估结果进行平均，并与EDWIN分数进行比较。使用SPSS 10.0（SPSS公司，伊利诺伊州芝加哥）对数据进行分析。
在连续35天的225个时间点，共评估了2647名18岁及以上的患者。护士和医师在拥挤程度评估方面显示出良好的心内一致性（加权kappa值为0.61，95%置信区间为0.53至0.69）。当急诊科被评为不繁忙、一般繁忙和非常繁忙时，EDWIN分数的中位数和四分位数间距（IQR）分别为1.07（IQR = 0.80至1.55）、1.55（IQR = 1.16至1.93）和1.83（IQR = 1.42至2.45）（p < 0.001）。急诊科在17个时间段（占所有时间段的6.5%）实施了分流，EDWIN中位数为2.77（IQR = 1.83至3.63），而未实施分流时EDWIN为1.45（IQR = 1.05至2.00）（p < 0.001）。EDWIN分数与作为次要终点选择的各种护理过程指标的相关性较弱。
EDWIN与工作人员对急诊科拥挤和分流情况的评估具有良好相关性。该指标可编入跟踪软件，用作“仪表盘”，在急诊科接近危机时提醒工作人员。如果在其他场所得到验证，EDWIN可能提供一种工具，用于比较不同急诊科的拥挤程度。
