Abstract

Background: National early warning score (NEWS) is consider the simplest system of physiological scoring attempts to identify deteriorating patients’ early so timely interventions can occur thus reducing serious adverse events. We aimed to evaluate the role of National early warning score in detecting and decreasing cardiorespiratory arrest amongst patients with acute coronary syndrome. Materials and Methods: a retrospective cohort study was undertaken on 60 patients with Acute Coronary Syndrome (ACS) at Coronary Care Unit (CCU). Data collection occurred over 3 phases. Phase I (Pre-NEWS data collection); physiological parameters were extracted retrospectively between 1 May 2019 and 30 July 2019 using Electronic Health Intelligence System (HIS). Phase II: one-month (1st -30th August, 2019); introduction and training of critical care nurses and doctors in CCU about NEWS. Phase III: Post NEWS data collection; physiological parameters were collected directly from the patients with ACS between 1 September 2019 and 30 November 2019. Results: the mean of NEWS, was 1.42 and 5.52 for the Post NEWS and Pre NEWS groups respectively with a statistically significant difference between them (p<0.001). It was noticed that a significant decrease in cardiorespiratory arrest and death in Post NEWS group (36.6%, 20%) versus Pre NEWS group (66.7%, 56.7%) respectively. Conclusion: The NEWS was significantly effective in decreasing occurrence of cardiorespiratory arrest and death. So, the NEWS is a useful tool to identify patients with ACS at greatest risk of cardiorespiratory arrest. Therefore, applying the NEWS as a part of routine nursing assessment for all patients with ACS is highly recommended.

1. Introduction

The first member of health team in CCU that usually detects any clinical changes occur in patients with ACS is the nursing team. By observing facial expressions and neuro-emotional behavior of patients and vital signs (VS) monitoring, these changes can be easily detected. The occurrence of these changes is associated with occurrence of cardiorespiratory arrest (CRA). Immediate detection of abnormalities increases the chance for timely intervention of patients with better quality of life survival. CRA is preceded by sudden disturbance of heart rate and respiratory rate followed by loss of consciousness, leading to irreversible brain damage and death if appropriate measures for patient's stabilization are not taken immediately. The basic role of critical care nurse for improving patient with ACS outcomes and decreasing unexpected deaths; is continuous monitoring for early identification of warning signs and rapid clinical response for deteriorating conditions ^{1, 2, 3, 4}.

The influx of patients becomes more and more than in the past in multidisciplinary hospitals. Typically, each hospitalized patient has a monitoring sheet in which the patient's vital signs are recorded. Scanning of this monitoring sheet can give insight to the doctor or nursing staff about the patient's condition. In overcrowded clinical area, by the doctor or nurses may not observe these parameters in the vital signs sheet. The total score may provide health care team with the best information than one vital signs parameter itself. Early warning scores use physiological and easy-to-measure parameters as vital signs and consciousness level to detect acute conditions, encourage early and rapid management, and predict death ^{5, 6}.

National Early Warning Points is a well-designed instrument used to help early identification and clinical worsening conditions response in patients with acute diseases ^{7, 8}. NEWS uses a simple recording system in which the physiological measurements such as respiration rate (RR), peripheral oxygen saturation, need oxygen supplementation, body temperature, systolic blood pressure (SBP), heart rate (HR) and level of consciousness which evaluated with the Alert, Verbal, Painful and Unresponsive (AVPU). In an acute medical setting, effective clinical treatment can be started in time when early identification of a deteriorating patient occurs. This applies to a different of conditions such as myocardial infarction (MI), unstable angina, septicemia, and cerebrovascular events, including stroke ^{9, 10, 11, 12}.

The National Early Warning Score can be easily applied in a district-level hospital, and this can detect patients who are on the verge of clinical deterioration and who need for admission to the intensive care unit for close monitoring ⁶. It eliminates the need to completely rely on the critical care nurse's clinical judgment to elicit a response. The responsibility and duty of informing doctors of the appropriate degree of NEWS and monitoring the patient at appropriate intervals rely on critical care nursing staff. The doctor should assess the patient again to evaluate the response to the initial treatment and determine the need for additional course of work accordingly ^{13, 14}. Therefore, this study aimed to explore the role of national early warning score in detecting and decreasing cardiorespiratory arrest amongst patients with acute coronary syndrome.

2. Materials and Methods

A retrospective cohort study was conducted in this study.

What is the role of national early warning score in detecting and decreasing cardiorespiratory arrest amongst patients with acute coronary syndrome?

The study was conducted on 71 adult patients with acute coronary syndrome and admitted to CCU over 72 hours period. We excluded patients less than 18 years of age, patients discharged at the same day of admission and patients with chronic diseases as diabetes and hypertension. The subjects were not randomly assigned into two groups (Pre NEWS group =38 patients, and Post NEWS group= 33 patients). Eleven patients were excluded from the study due to incomplete physiological parameter observations, 8 from the Pre NEWS group and 3 from the Post NEWS group. Therefore; the final analysis of data was done on 60 patients Figure 1.

This study conducted on coronary care unit that containing 16 beds in 3 separated rooms at Orman University Hospital for the Heart - Assiut, Egypt in the period between 1^st of May and 30^th of November 2019.

Three tools were used in this study after reviewing of the related literatures.

Tool one: - Patients characteristic assessment tool:

This tool used to assess the studied patients regarding demographic data included patient’s age, gender in addition to patient’s medical diagnosis to form base line data to be compared with.

Tool two: The National Early Warning Score:

This tool was developed by the Royal College of Physicians (RCP) in 2012 ¹⁰. It is used to improve acute disease evaluation, detect clinical deterioration, and initiate a competent clinical response in a timely manner ¹⁵. It depends on seven easily obtained clinical parameters and produces a total score between 0 and 20. It includes six physiological parameters (respiratory rate, oxygen saturation, temperature, systolic blood pressure, heart rate and need for supplemental oxygen) as well as the AVPU scale (“alert, voice, pain, unresponsive”). The patient's responsiveness / level of consciousness as follows: Alert: fully awake patient, but not necessarily fully oriented), will spontaneously open his or her eyes, will respond to voice, and will have a proper motor function. Voice: some kind of response is made by patient (via eyes, voice or movement) when you talk to them, although the response could be as little as a moan, or slight limb movement. Pain: The patient responds (again, via eyes, voice or movement) following the application of noxious stimulus, such as sternal rub. Unresponsive: there is no any response to the eye, sound, or movement of any sound or pain by patient. Patients are at "low risk" with a score of 4 and below, at "medium risk" with a total of NEWS scores of 5 or 6 or if they score an individual parameter at 3 and they are in "high risk" with a sum of NEW news exceeding 6 ¹⁶.

Tool three: Patients outcomes assessment sheet

This tool was used to assess the studied patients regarding negative outcomes during the first 72 hours of CCU admission. The following outcomes were documented: cardiorespiratory arrest, dysrhythmias and death.

• Research proposal approved from Ethical Committee in the Faculty of Nursing, Assiut University and permission to conduct this study obtained from the responsible hospital authorities in cardiology department.

• Tools (one and three) was developed by researchers after reviewing of the related literatures and tested for content validity by a jury of (5) specialists in the field of critical care nursing and cardiology from Assiut University, and necessary modifications was done. At least, a pilot study was conducted on 10% patients to evaluate the feasibility and applicability of the tools and the necessary modifications was done.

• For both groups, demographic data included patient’s age, gender in addition to patient's diagnosis were collected based on documentation in the chart on admission

Data collection (analysis of NEWS) occurred over 3 phases.

Phase I (Pre-NEWS data collection) for Pre- NEWS group:

Six physiological parameters as well as the AVPU scale of patients with ACS admitted over a 3 months period between 1 May 2019 and 30 July 2019 were extracted retrospectively using Electronic Health Intelligence System (HIS). The monitoring of patients was according to the existing care management system. Vital signs observation sets were monitored based on a decision was made by the primary physician depending on the clinical condition of patients.

Phase II: (one-month training period from 1^st -30^th August 2019)

• Introduction and training of critical care nurses and doctors in CCU about national early warning score (NEWS). The NEWS scoring system (Table 1).

• Training was conducted to 32 members of health care team (8 doctors and 24 nurses) was divided into 4 subgroups included 6 nurses and 2 doctors each session.

• Training was applied by the researchers in coronary care unit at Orman University Hospital in twelve sessions, 3 sessions per week for 4 consecutive weeks, and each session constituted of 45 minutes from 10 am: 10:45 am.

• In first session, researchers explained introduction of NEWS. Second session, includes demonstration and re-demonstration about NEWS. Third session, interpretation of NEWS on patients.

• Teaching methods were PowerPoint presentation, videos, posters and booklet about NEWS was developed by the researchers based on reviewing the related literature.

Phase III: Post NEWS data collection for Post NEWS group:

• During clinical assessment, trained critical care nurses and doctors in CCU recorded the six NEWS physiological parameters, each being allocated a score reflecting the magnitude of physiological disturbance. If supplemental oxygen is required to maintain oxygen saturations, two additional points are given to the aggregated physiological score, to give an individualized NEW score for the patient with ACS admitted to CCU over a 3 months period between 1^st of September 2019 and 30^th of November 2019. According to the NEWS, the health care team in CCU determined the frequency of observations and implemented the appropriate clinical response.

• The parameters of NEWS e recorded and acted upon by staff who were trained and competent to undertake these procedures both electronically and manually, and who understand the clinical significance of deviations from the patient’s norm.

• Completeness of data was checked daily at bedside by the researchers. Six physiological parameters (respiratory rate, oxygen saturations, temperature, systolic blood pressure, heart rate, and AVPU score) and patient need for supplemental oxygen were recorded on admission and then frequency of observation and clinical response depend on NEWS.

• The axillary temperature was taken. AVPU scores were scored according to best response at time of blood pressure measurement.

Statistical analysis was performed using statistical software SPSS Version 16.0. Data were presented using descriptive statistics in the form of frequencies (percentages) and means and standard deviations. Quantitative variables were tested using independent t-test and qualitative variables were tested using chi square test. P value of <0.05 was considered significant.

3. Result

Table 2 shows that the mean age of the Post NEWS group was 43.58±13.12 and was 46.7211.63 among the Pre NEWS group and 73.3 % of both groups were males. Nearly half of Post NEWS and Pre NEWS groups were diagnosed as ST-segment elevation myocardial infarction (53.3%, 50%) respectively without statistically significant difference between both groups in relation to demographic data.

Table 3 showed that there was a statistically significant difference between the both groups in all parameters of NEWS through the first three days of CCU admission except systolic blood pressure and need for oxygen supplementation (p<0.001). Regarding to the mean sore of NEWS, it was 1.42 and 5.52 for the Post NEWS and Pre NEWS groups respectively and there was a statistically significant difference between them (p<0.001).

Table 4 showed that there was statistically significant decrease in the occurrence of dysrhythmias, cardiorespiratory arrest and death among Post NEWS group versus Pre NEWS group (p>0.05).

4. Discussion

One of the recommended parts of early identification and response to patient deterioration is Early warning score (EWS) ¹⁷. NEWS is the highest performing scoring system in relation to other early warning scores. EWS scores are used by health care teams to identify early signs of clinical deterioration and the need for increased intensive care, such as increased critical nursing care, reporting to the care provider, or rapid response team activation (RRT) or medical emergency team ¹⁸.

Regarding to gender, it was noticed that the majority of patients in the Post NEWS and Pre NEWS groups were males and diagnosed with elevated ST segment MI without statistically significant difference between the two groups. This might be related to changes of the heart and blood vessels that occur with aging. Also, this can be explained to the fact that exposure to life stress is higher in males, and female hormones may protect female from ACS. These findings were in line with ⁸ who found that 51% of patients were male.

Results of this study represented that there was a considerable difference between the both groups in all parameters of NEWS through the first three days of CCU admission except systolic blood pressure and need for oxygen supplementation. This may be attributed to NEWS is indicator for worsening patient with ACS and need for close observation and rapid clinical response. These findings were in line with ¹⁸. Observational study which suggest that patients always have clinical deterioration signs up to 24 hours prior to a serious clinical event requiring intensive interventions.

The current results also revealed that nearly half of patients in both groups needed oxygen therapy supplementation. This might be related to the patients with ACS may need for supplemental oxygen to increase myocardial oxygen supply. In this concern, ¹⁹ noted that almost all the observations (82.63%) patients received oxygen.

The findings of the current study presented that the mean sore of NEWS for Post NEWS group was significantly low versus Pre NEWS group. This finding is supported by ⁸ who stated that mean NEWS score was 1.49 and 6.52 for all patients and patients who had any of the composite outcomes, respectively.

In the present study the survival to CCU discharge improved significantly from 43.33% for Pre NEWS group to 80% for Post NEWS group. This could be attributed that the use of NEWS can assist the health care team in CCU in prioritizing their work by identifying the patients in need of urgent review. It is similar to the results of ², who studied Effectiveness of Modified Early Warning Score (MEWS) in the Outcome of In-Hospital Adult Cardiac Arrests in a Tertiary Hospital, and stated that the survival to hospital discharge improved significantly from 5% to 16.82% pre and post MEWS.

In the current study, mortality rate was 56.7% for Pre NEWS group and decreased significantly to 20% for Post NEWS group. In this regard ²⁰ who studied an audit for eight-year before and after the introduction of modified early warning score (MEWS) schemes, for patients admitted to the third referral intensive care unit after CPR and found that patients who underwent cardiopulmonary resuscitation had a dramatic reduction in in-hospital mortality at the two hospitals, from 52 to 42% (P, 0.05) and from 70 to 40% (P, 0.0001), respectively. On the other hand, this is not supported with results of ²¹ and other pre-post observational studies ^{22, 23}, who have documented no significant differences in the overall mortality rate.

The present study also revealed a significant reduction of the rate of cardiac arrest from 66.7% among Pre NEWS group to 36.6% among Post NEWS group. In this regard, ²⁰ examined the percentage of cardiac arrest calls per adult admission and found a decrease in the two participating hospitals, from 0.4 to 0.2% in one location (P, 0.0001) and from 0.34 to 0.28% (P, 0.0001) in the other one. These results in contrast to ²² who have documented no difference in cardiac arrest after EWS implementation

• This scoring was done in one location and the results cannot be generalized to patients in other medical or surgical conditions in the entire hospital.

5. Conclusion

We have demonstrated that NEWS is a good predictor for early recognition and management of worsening condition of patient with acute coronary syndrome and decreasing incidence of cardiac arrest and death.

6. Recommendation

• Each teaching hospital has to implement this early warning system throughout the institution for early prediction of clinical deterioration in intensive care units.

• The NEWS should be obligatory applied by all members healthcare team who responsible from the assessment and monitoring of critically ill patients in intensive care units.

• This trial also provides a further evaluation for NEWS to review other specific diagnoses.

References