A study of the effect of introduction of JTAS in the emergency room

Aim The purpose of this study was to better understand the effects of introducing the Japan Triage and Acuity Scale (JTAS) in the emergency room for walk‐in patients. Methods A simple triage was used in Term A (from April 2006 to December 2010, 4 years and 9 months) and the JTAS was introduced in Term B (from January 2011 to September 2015, 4 years and 9 months). The number of patients who had a sudden turn for the worse after arrival in the emergency room and the time between attendance and emergency catheterization (TBAEC) due to acute coronary syndrome were reviewed. Results There were 653 patients in Term A and 626 patients in Term B who were finally diagnosed as having serious causes. There was no significant difference in the frequency of a sudden turn for the worse between the two terms. There were 182 patients in Term A and 167 patients in Term B who underwent emergency catheterization due to acute coronary syndrome. When ST elevation was recognized in the first electrocardiogram, the median time between attendance and medical attention during Term B improved significantly, by 4.5 min. However, there was no significant difference in medians for TBAEC. When ST elevation was not recognized, there was no significant difference between the two terms, neither in terms of median time between attendance and medical attention, nor TBAEC. Conclusion The data suggests that the effects of introducing the JTAS in the emergency room were restrictive in these two aspects.


INTRODUCTION
A FTER THE INTRODUCTION and spread of USoriginated emergency medicine in Japan, doctors in some specific hospitals are required to treat patients with conditions of varying seriousness, so an adequate triage by nurses has become more important for walk-in patients in emergency rooms. [1][2][3] Although there are several triage systems by nurses in emergency rooms, 1,4 the Japanese Society for Emergency Medicine and the Japanese Association for Emergency Nursing are developing the Japan Triage and Acuity Scale (JTAS, see Appendix) as the standardized triage system in emergency departments. 5,6 Before the introduction of this kind of systematic triage system, simple triage systems were used in a lot of hospitals. However, there are no studies comparing the effects before and after the introduction of the JTAS.
Among the variety of patients in the emergency center at Aizawa Hospital (Matsumoto, Japan), who visit by themselves with or without somebody's support or who are transferred by ambulance, some patients take a sudden turn for the worse, including cardiopulmonary arrest, after arrival. Even though such serious patients fall into cardiopulmonary arrest just after arrival, problems of triage are not likely to occur as emergency care is immediately started.
When a do not attempt resuscitation (DNAR) order has already been decided by the family, triage problems are not likely to occur either as emergency care is not expected. 7,8 However, when the condition of walk-in patients becomes suddenly worse in the waiting room or before and during examination, triage problems possibly arise.
According to a previous report, treatment of patients with serious diseases and myocardial infarction started more quickly after introduction of triage nurses. 1 So, it is important to assess how long the door-to-balloon time has shortened since the introduction of JTAS for patients with acute coronary syndrome, such as ST-elevated myocardial infarction. [9][10][11] We previously reported patients who developed cardiopulmonary arrest at the emergency room after arrival. 12,13 In this report, we study the effects of introducing the JTAS for walk-in patients in the emergency room using two aspects: (i) the frequency of sudden turn for the worse after arrival among patients who are diagnosed as having serious diseases; (ii) the shortening of the interval to emergency catheterization for patients who are likely to have acute coronary syndrome.

METHODS
F ROM APRIL 2006 to September 2015 (9 years and 6 months), there were 372,908 walk-in patients who visited the emergency room at Aizawa Hospital. A simple triage was used in Term A (from April 2006 to December 2010, 4 years and 9 months) and the JTAS was introduced in Term B (from January 2011 to September 2015, 4 years and 9 months). Electronic charts of walk-in patients who were finally diagnosed as having serious diseases were reviewed to select patients with a sudden turn for the worse after arrival. Patients who were referred from other medical institutions after final diagnosis or who had reservation for admission were excluded. According to a previous simple triage, nurses with longer than 3 years of experience undertook triage using 1 or 2 min to pick up patients who had unstable vital signs or various serious symptoms such as loss of consciousness, dyspnea, headache, chest pain, abdominal pain, and back pain. Approximately 80% of patients were checked by triage nurses, and only vital signs were measured by nurses in other patients.
We classified patients as having a serious condition if they died at the emergency room, were transferred to other hospitals for further treatment, or were admitted to the intensive care unit (ICU) or stroke care unit (SCU) at Aizawa Hospital. Among patients who were admitted to the ICU or SCU, those with less serious conditions, for instance, non-perforated appendicitis, small cerebral infarction/hemorrhage, or acute drug intoxication, who might be able to be treated in a standard ward, were excluded from the serious condition group. We defined a sudden turn for the worse when patients had cardiopulmonary arrest, tracheal intubation, non-invasive positive pressure ventilation, cardioversion, or sudden loss of consciousness in the emergency room. However, patients with transient loss of consciousness or epilepsy were excluded from sudden turn for the worse.
Of these patients, we investigated age, sex, time between attendance and medical attention (TBAMA), causal diseases of serious condition, time between attendance and sudden turn for the worse, events of sudden turn, causal diseases of sudden turn, and time/location circumstances of sudden turn using electronic charts. We also investigated the existence of ST elevation at first electrocardiogram and entrance time of emergency catheterization in patients who were likely to have acute coronary syndrome. The number of patients who had a sudden turn for the worse in the emergency room and the time between attendance and emergency catheterization (TBAEC) due to acute coronary syndrome were compared between Term A and Term B. The TBAMA was estimated using electronic charts of doctors or nurses when records of starting time of medical attention were lacking. Triage color of JTAS was investigated in Term B. According to the triage method of Aizawa Hospital, patients who needed immediate treatment were regarded as red (emergent level), not as blue (resuscitation level), and transferred to treatment rooms immediately. We did not distinguish green (less-urgent level) from white (non-urgent level).
StatView Japanese Version 5.0 (SAS Institute, USA), was used for the statistical analysis. Fisher's exact test and the Mann-Whitney U-test were used for the analysis of the frequency of a sudden turn for the worse and TBAEC, respectively. The results of the analysis were regarded as significant when P-values were less than 0.05.

T HERE WERE 176,836 walk-in patients in Term A and
196,072 patients in Term B. After exclusion of patients who went home or were hospitalized to standard wards, 54 patients in Term A and six patients in Term B who were admitted to the ICU or SCU and might have been able to be treated at standard wards were excluded from the serious condition classification. There were 1,279 patients, 653 (0.37%) in Term A and 626 (0.37%) in Term B, who were finally diagnosed as having serious causes ( Fig. 1

min, and time between attendance and sudden turn was
185.2 min. The following events were associated with the sudden turn: 16 patients with cardiopulmonary arrest, 10 with tracheal intubation, one with cardioversion, and three with sudden loss of consciousness in Term A. In Term B, there were 13 patients with cardiopulmonary arrest, eight with tracheal intubation, five with non-invasive positive pressure ventilation, three with cardioversion, and seven with sudden loss of consciousness. The following causal diseases were associated with sudden turn for the worse: one patient with central nervous system, 11 with cardiovascular, nine with respiratory, five with gastrointestinal, and two with other diseases in Term A. In Term B, there were five patients with central nervous system, 11 with cardiovascular, seven with respiratory, six with gastrointestinal, and seven with other diseases. Regarding the time/location circumstances, there was one patient (3.3%) whose sudden turn for the worse occurred in the waiting room, nine patients (30%) before and during examination, 15 (50%) after examination, and 5 (16.7%) with DNAR in Term A. There were four patients (11.1%) whose sudden turn for the worse occurred in the waiting room, four (11.1%) before and during examination, 24 (66.7%) after examination, and four (11.1%) with DNAR in Term B. There were 10 patients whose sudden turn for the worse occurred in the waiting room or before/ during examination in Term A, and eight patients in Term B.
Of these patients, there was one patient each in Term A and Term B for which the waiting time was longer than 15 min and the sudden turn for the worse occurred in the waiting room or within 30 min of the start of medical attention. There was no significant difference in the frequency of a sudden turn for the worse between the two terms (Table 3). There were 182 patients in Term A and 167 patients in Term B who underwent emergency catheterization (Fig. 1,  Table 4). There were 134 men, 48 women, 87 patients aged 70 years or older, and 95 patients younger than 70 years in Term A. There were 136 men, 31 women, 62 patients aged 70 years or older, and 105 patients younger than 70 years in Term B. In Term B, the triage colors were red in 123 (73.6%) patients, yellow in 28 (16.8%), green in 13 (7.8%), and unknown in 3 (1.8%). In terms of causal diseases of emergency catheterization, in Term A, there were 91 patients (50.0%) whose ST elevation was recognized in the first electrocardiogram, 69 (37.9%) whose asynergy was recognized in the ultrasound cardiography, and 22 (12.1%) with other reasons. There were 74 (44.3%), 51 (30.5%), and 42 patients (25.2%), respectively, in Term B. Median TBAMA in Term A was 19 min in total, 20 min when ST elevation was recognized in the first electrocardiogram, and 17 min when ST elevation was not recognized. Median TBAMA in Term B was 19, 15.5, and 20 min, respectively. When ST elevation was recognized in the first electrocardiogram, the median TBAMA of Term B improved significantly, by 4.5 min (Fig. 2, Table 4). Table 3. Association between walk-in patients diagnosed as having conditions with serious causes and patients whose condition took a sudden turn for the worse in the emergency room at Aizawa Hospital (Matsumoto, Japan)  Median TBAEC in Term A was 102 min in total, 74 min when ST elevation was recognized in the first electrocardiogram, and 130 min when ST elevation was not recognized. Median TBAEC in Term B was 100, 67.5, and 130 min, respectively. When ST elevation was recognized in the first electrocardiogram, median TBAEC of Term B improved by 6.5 min, however, there was no significant difference ( Fig. 3, Table 4). With regard to treatment at emergency catheterization, there were 135 patients with stent, and 47 patients without stent in Term A. There were 135 and 32 patients, respectively, in Term B.

DISCUSSION
A FTER THE INTRODUCTION and spread of US-originated emergency medicine in Japan, too many patients are likely to visit some specific hospitals, so an adequate triage by nurses became especially important for walk-in patient in emergency rooms. 1-3 Aizawa Hospital is an emergency and critical care center in the Matsumoto area of Japan (background population is approximately 400,000), and approximately 500 beds are available. In addition to full-time emergency doctors, approximately 30 nurses are assigned at the emergency center, and there are approximately 20 nurses who attended the JTAS provider course. They worked on a day and night shift schedule, and treated a variety of patients who visit by themselves or who were transferred by ambulance.
In the 2014 fiscal year, the number of walk-in patients was 38,934 (average, 106.7 daily), and the number arriving by ambulance was 7,036 (average, 19.3 daily). The situation of overcrowding changes every day; more than 300 patients may visit in 1 day on consecutive holidays such as new year's holiday or Bon-festival. Under such situations, the introduction of adequate triage nurses and a systematic triage system such as

CONCLUSION
A FTER THEIR INTRODUCTION of JTAS in the emergency room, there was no significant difference in the frequency of a sudden turn for the worse. In patients with suspected acute coronary symptoms and subsequent emergency catheterization, when ST elevation was recognized in the first electrocardiogram, median TBAMA improved significantly, by 4.5 min; however, there was no significant difference in median TBAEC. The data suggest that the effects of introducing JTAS in the emergency room were restrictive in these two aspects. In order to disclose the effect of JTAS in the emergency room, further studies, for instance, how much under-triage is reduced or what kind of clinical improvements are obtained, are necessary.

APPROVAL OF THE RESEARCH PROTOCOL
T HIS STUDY WAS approved by the ethical review board at Aizawa Hospital.

CONFLICT OF INTEREST
N ONE DECLARED.