Preventing unrecognized deterioration & improving outcomes of critically ill patients using the National Early Warning Score 2 in a high dependency unit in Bangladesh: A quality improvement project

Abstract

This Quality Improvement Project (QIP) aimed to assess the acceptability and utility of the National Early Warning Score 2 (NEWS2) in a Bangladeshi level-2 care setting. All nurses and physicians were trained on NEWS2 scores and a proper response before starting the QIP. Utilization of NEWS2 and patient outcome were documented and analyzed. Acceptability was acknowledged by increase in utilization, and utility by reduction in unrecognized deterioration of patients. The modified NEWS2 was well adopted and utilized by the nursing staff. There was a statistically significant reduction in unrecognized deterioration leading to cardiac arrest and the need for transfer to the Intensive Care Unit after implementation of NEWS2. With adequate training, motivation and appropriate modification, NEWS2 can become a well-accepted, widely adopted and realistic bedside monitoring tool in resource-limited settings like Bangladesh.

Keywords

NEWS2 Bangladesh unrecognized deterioration critically ill HDU

Introduction

High dependency units (HDU) play a crucial role as an intermediate or ‘level-2’ setting for monitoring and treatment of vulnerable patients whose predicted risk of clinical deterioration is high.¹ Although patients in the HDUs are usually continuously monitored with advanced detection systems to detect variations in various physiological parameters, there is always a risk of sudden and unexpected deterioration.² Failure to recognize or appreciate such changes early and properly will compromise escalation of treatment, including transfer to level-1 care, and often lead to serious adverse events.^3,4

Physiological variables, viz. heart rate, blood pressure, respiratory rate, oxygen saturation, temperature and level of consciousness, are standard measurements whose subtle changes may indicate the seriousness of an ongoing illness as well as a warning of worsening clinical condition.^5,6

Nurses are responsible for the surveillance of patients.^7,8 Evidence suggests that in-hospital patient care and outcome is heavily dependent on the level of instruction and extent of training of the existing nursing staff.^8,9

Bangladesh, a low-to-middle income south-Asian country with a fast growing economy, has achieved enviable improvement in all fields of the ‘Millennium Development Goals’, in the last decades.^10,11 However, the field of critical care struggles, as this sector lacks proper infrastructure, appropriate facilities and adequate qualified staff.^9,10,12,13 There is limited provision of formal teaching and training of critical care nursing staff,^9,12,13 especially in the realm of recognition of sudden patient deterioration.^9,13

Early Warning Scores, calculated from regularly observed bedside physiological parameters, have been proven to be a valuable tool to assess disease severity and prompt decision making.⁵ Such a scoring system does not require any costly investigation or invasive procedure, is easy to measure and document, and so is appropriate for resource limited settings.

The National Early Warning Score 2 (NEWS2) is a standardized, sensitive, efficient, widely used and validated ‘track-and-trigger’ system, designed for rapid detection and identification of those patients requiring escalation of level of care.^6,14,15 It has a structured, visually prominent and easy-to-use chart, where the physiological parameters are more easily documented and changes in scores are rapidly identified.⁵ The NEWS2 chart is ‘user-friendly’ and has been proven to be efficient.^5,6 It is appropriate for use even by inexpert medical and nursing staff.

No published data of the frequency of unnoticed deterioration (requiring treatment escalation to level-1 care) or sudden cardiac arrest in HDU patients exist. However, from our own HDU, at one of the largest multidisciplinary hospitals in Bangladesh between March 2019 and February 2021, we showed that 6.6% of patients needed to be transferred to an Intensive Care Unit (ICU) after resuscitation and 2.6% developed sudden cardiac arrest but could not be resuscitated, all because of missing the warning signs of deterioration. We therefore developed a Quality Improvement Project (QIP) to assess the utility and effectiveness of NEWS2, and to determine its acceptability and adaptability within our set-up.

Methods

Our 12-month QIP was conducted from 1 March 2021 to 28 February 2022 in our 20-bedded HDU, which has c.16 daily in-patients with c.300 monthly admissions. The majority admitted have sepsis (with or without shock), hypovolemic shock (mostly due to gastroenteritis & gastrointestinal haemorrhage), respiratory failure, acute kidney injury, metabolic acidosis, diabetic complications, or poisoning. Some are admitted as a ‘step-down’ from the ICU.

Before commencing our QIP, all involved were taught about the benefits and utility of NEWS2 and trained on its effective application through informal lecture presentations and bedside hands-on training sessions, planned and conducted by the project leader (PL).

The QIP team primarily consisted of the PL, the Senior House Officer (SHO) on-duty, nurse-manager and charge nurses. All the nursing staff and physicians engaged in the HDU actively participated in collecting and recording NEWS2 scores. Ethical clearance for this study was obtained from the hospital; as no personal data nor identifiable information was used in the project, patient consent was waived.

Recording was based on the NEWS2 (© Royal College of Physicians 2017), but modified according to local settings, practices and convenience to promote ease of use and compliance. Thus, degrees Fahrenheit (°F) was used instead of Centigrade (in order to prevent error during conversion) and multiple rows for the same scores (as in the NEWS2 chart) were collated into a single row (to avoid miscalculation).

The chart used shades of grey to cut costs and improve printing convenience (Supplemental Figure 1). Charts were placed with other documents added to patients’ medical records. Their interpretation and response tables were hung in walls and notice boards in clearly visible sites within the HDU, to make sure that the reaction was appropriate.

All adult (age ≥18 years) patients of both genders admitted at the HDU, except those declared as ‘Do Not Intubate/Do Not Resuscitate (DNI/DNR)’, deemed equivalent to ‘Do Not Attempt Cardiopulmonary Resuscitation’ (DNACPR) in our setting, were included.

Data collected were: (1) The number of patients developing sudden cardiac arrest – defined as patients in whom early changes of the bedside parameters were missed/unnoticed and no measures were taken till cardiac arrest took place and the patient could not be resuscitated. Those patients, whose clinical deterioration was detected early, but despite all appropriate measures, developed cardiac arrest, were not to be considered. (2) The number of patients required to be transferred to the ICU, defined as those in whom early changes in bedside parameters had been missed or unnoticed but when found, were beyond the capacity of the HDU to manage or resuscitate successfully. Those reverting after unnoticed sudden cardiac arrest who were transferred to ICU were also included in this group. Those patients whose clinical deterioration was detected early, but despite all appropriate measures, had to be transferred to ICU, were not to be considered. (3) The number and percentage of the cases where NEWS2 were calculated accurately by the nursing staff. (4) The number and percentage of cases where changes of NEWS2 were reported appropriately by the nursing staff.

To ensure compliance by the nursing team, calculation and recording of NEWS2 were done at least once at the beginning of each shift (three nursing shifts daily), and more frequently during the shift if needed. Any reportable changes in NEWS2 score were mentioned to on-duty doctors in the department.

At the end of each shift, the charge nurse documented all calculated EWS, and also data of patients’ transfer (including ‘to ICU owing to missed chances’ or ‘death owing to missed chances’), during that shift, on the prescribed chart, designed using MS-Excel (Microsoft Office-365, 2021 © Microsoft) (Supplemental Figure 2). After completing documentation of data from all shifts, the nurse manager and SHO on-duty reviewed the data for accuracy of calculation and appropriateness of reporting of changes of NEWS2 in previous 24 h. The PL supervised all activity, compiled all the data, and analyzed them monthly.

After commencement of the QIP, fortnightly motivational sessions and bedside hands-on training sessions for the nurses were continued to improve the integrity, compliance and accuracy of the documentation and reporting of the NEWS2.

Regular feedback from nursing staff was taken and considered seriously. One major issue appeared to be the ‘dull monotonous grey colour’ of the chart, which resulted in frequently missing numbers because ‘all were shades of grey’. The NEWS2 recording and response charts were then replaced with ‘traffic signal’ coloured (green, yellow, amber and red representing scores 0, 1, 2 and 3, respectively) recording charts (Figure 1(A) and (B)) from the fifth month onwards.

Figure 1.

(A) Modified ‘traffic-colour’ coded NEWS2 recording chart. (SpO2 = oxygen saturation, O2 = oxygen, L/min = litre/min, mmHg = millimetres of mercury, °F = degree Fahrenheit). (B) Modified ‘traffic-colour’ coded NEWS2 response chart.

Data on the number of patients needing transfer to ICU and who died due to sudden cardiac arrest (both for delay in recognizing deteriorating patients and in intervention) after implementation of NEWS2 at the HDU during the QIP were compared with numbers of similar events in previous 24 months (prior to implementation of NEWS2). Data were compared by unpaired t-test to assess the improvement in patient outcome following the implementation of NEWS2.

Only when NEWS2 was calculated and recorded correctly at all the shifts for each patient during their stay in HDU, was it considered as ‘appropriately calculated’. One ‘appropriately calculated’ represents one patient included in the QIP. Any gap in the recording was not documented. Similarly, ‘reportable changes’ and ‘appropriately reported’ also represents for one patient only. Total numbers of events of recording of accurately calculated EWS and appropriate reporting were documented, and their percentage was analyzed monthly to assess where interventions were required and to evaluate the success of implementation of the newly applied intervention.

None of the collected data contained any patient identifiable information, and all data were recorded, analyzed, and saved in the hard drive of a password protected computer at the HDU, accessible only to the PL.

Results

All physicians and nurses were found capable of properly calculating scores, when tested individually in an informal way. Attendance of nursing staff at the fortnightly motivational & training sessions was c.85%.

A total of 3835 patients were admitted to the HDU in the study period. Among them, seven were excluded as they were declared DNI/DNR. In the first five months (March to July 2021), NEWS2 was properly calculated and documented in 68.5% (1086/1585 patients admitted) and changes were reported properly in 58.4% (405/693 patients who showed reportable changes). However, the situation improved significantly when the coloured chart was introduced. From August 2021 to February 2022, NEWS2 was calculated and documented properly in 97.7% (2192/2243 patients admitted) and changes were reported properly in 98.7% (1137/1152) (Figure 2).

Figure 2.

Flowchart describing the methods and results of the QIP.

On average, NEWS2 was calculated and documented properly in 85.4% and changes in score was appropriately reported in 81.2% cases, during the total one-year period of the QIP (Table 1 and Figure 3). After introduction of the coloured chart, fortnightly sessions were no longer required for the nursing staff.

Figure 3.

Visual representation of calculation, recording and reporting of NEWS2, with response to the interventions taken to improve compliance.

Table 1.

Numbers and percentages of calculation and reporting of NEWS2.

Month/Year	Total	EWS appropriately	%	Reportable	Appropriately	%
Month/Year	patients	calculated	%	changes	reported	%
Mar ‘21	311	144	46.3	127	29	22.8
Apr ‘21	264	139	52.7	88	49	55.6
May ‘21	393	253	64.4	139	89	64.1
Jun ‘21	290	247	85.2	166	107	64.5
Jul ‘21	327	303	92 . 7	173	131	75.7
Aug ‘21	295	260	88.1	188	178	94.7
Sep ‘21	307	302	98.4	184	184	100
Oct ‘21	290	289	99.7	163	163	100
Nov ‘21	308	308	100	119	117	98.3
Dec ‘21	329	321	97.6	166	164	98.8
Jan ‘22	316	316	100	173	173	100
Feb ‘22	398	396	99.5	159	158	99.4
Total	3828	3278	85.4	1845	1542	81.2

EWS calculated and reported appropriately in >90% cases has been highlighted in bold letters.

Numbers of patients needing transfer to ICU and who died owing to sudden cardiac arrest (both for delay in recognizing deteriorating patients and in intervention) were compared with similar data (collected from the mortality and morbidity committee reports). There was a statistically significant reduction in events of sudden unrecognized cardiac arrest (0.35% vs 2.6%, p = <0.0005), and ICU transfer for missing early warnings of deterioration (2.33% vs 6.6%, p = <0.0005) after implementation of the EWS (Table 2 and Figure 4).

Figure 4.

Visual representation of percentages of sudden death and ICU transfer, before and after implementation of NEWS2. (The duration between Apr-20 to Jun-20 is highlighted to mark the time when HDU temporarily accommodated COVID-19 infected patients. The data do not represent the situation at regular time.).

Table 2.

Numbers and percentages of sudden death and ICU transfer, before (Mar-19 to Feb-21) and after (Mar-21 to Feb-22) implementation of NEWS2.

Mon/Year	ICU tr	%	Death	%	Total patients
Mar ‘19	19	6.1	9	2.9	315
Apr ‘19	16	5.2	5	1.6	309
May ‘19	21	7.3	10	3.5	287
Jun ‘19	18	5.5	11	3.4	327
Jul ‘19	24	9.8	8	3.3	244
Aug ‘19	19	7.2	8	3.1	263
Sep ‘19	29	9.4	7	2.3	310
Oct ‘19	22	5.9	9	2.4	376
Nov ‘19	16	4.3	6	1.6	372
Dec ‘19	11	3.7	7	2.4	294
Jan ‘20	15	4.9	9	2.9	302
Feb ‘20	13	3.7	7	1.9	356
Mar ‘20	23	6.2	14	3.8	369
Apr ‘20	17	14.9	6	5.3	114
May ‘20	6	10.2	1	1.7	59
Jun ‘20	8	19.5	2	4.9	41
Jul ‘20	18	4.8	11	2.9	377
Aug ‘20	19	5.5	9	2.6	344
Sep ‘20	15	4.7	7	2.2	320
Oct ‘20	13	3.3	5	1.3	389
Nov ‘20	15	4.9	6	1.9	304
Dec ‘20	16	5.6	5	1.8	284
Jan ‘21	11	2.9	7	1.9	367
Feb ‘21	16	3.5	3	0.7	457
Total	400	6.6	172	2.6	7180
Mon/Year	ICU tr	%	Death	%	Total patients
Mar ‘21	12	3.9	3	0.9	311
Apr ‘21	10	3.8	2	0.8	264
May ‘21	9	2.3	3	0.8	393
Jun ‘21	11	3.8	1	0.4	290
Jul ‘21	10	3.1	1	0.3	327
Aug ‘21	9	3.1	2	0.7	295
Sep ‘21	7	2.3	0	0	307
Oct ‘21	3	1.1	0	0	290
Nov ‘21	4	1.3	0	0	308
Dec ‘21	7	2.1	1	0.3	329
Jan ‘22	3	0.9	0	0	316
Feb ‘22	1	0.3	0	0	398
Total	86	2.33	13	0.35	3828

The duration between Apr-20 to Jun-20 is highlighted to mark the time when HDU temporarily accommodated Covid-19 infected patients. The data do not represent the situation at regular time.

Total numbers & percentages are highlighted in bold letters.

Discussion

Vital signs are the easiest, inexpensive and widely used parameters and probably the most important information gathered on any patient in hospital. Around 90% of cardiac arrests, and clinical deterioration due to other causes, were always preceded by alteration of vital signs. Effective appreciation of such changes in physiological parameters can prevent catastrophic events.^2,15

EWS systems have been proven to be an invaluable tool for detecting early clinical deterioration, assessing disease severity and prompting decision making, resulting in improved patient outcome, and better quality of patient care.^5,16 A wide range of such scoring systems are available, but the National Early Warning Score (NEWS), implemented by the Royal College of Physicians in 2012, and updated in 2018 (NEWS2) has outperformed the others in accuracy of detection & prediction of worsening patients.^6,16,17 NEWS2 has been designed for rapid detection and identification of those who require escalation of level of care, and effective response to acutely ill patients at the medical and surgical wards.^6,14,15 It has been standardized and validated in acute care settings and has been successfully used in prediction of ICU admission from the ER and discharge from ICU.^6,18,19 In addition, NEWS2 gives prognostic information in different clinical situation.^20,21 However, there is limited information of use of NEWS2 in level 2 care settings. Despite the inadequacy of evidence, we decided to use NEWS2 in HDU because of its structured, visually prominent and easy-to-use chart, which seemed to be a cheap, cost-effective and practical answer for Bangladesh's lagging-behind critical care services, where patients frequently worsened because of unrecognized subtle signs of deterioration by the manpower with inadequate training and skill. The practical and statistically significant improvement in the outcome of our critically ill patients, by increasing the detection of ‘early warnings’ and preventing unnoticed deterioration of patients, strengthens evidence further in favour of NEWS2 to be successfully used in level 2 care or HDU settings and manifest the success of our QIP.

Although NEWS2 has been effectively used in the neighbouring countries, for example, India,²² Pakistan²³ and Sri Lanka,²⁴ it was not in use in Bangladeshi hospital settings before this QIP. The inference can be expected to encourage its use in this and other developing country.

Adequate learning and appropriate training for the nurses are always important for any new things to be implemented.^7,8 Our well-planned training sessions had benefitted the process of implementation of NEWS2 for the first time. However, the most effective intervention appears to be the introduction of ‘traffic colour’ coded charts for calculating and recording of the NEWS2 by the nursing staff. Many authors have successfully improvised this colour code in their research.^25,26

Limitations of this QIP are, firstly – that this study may be confused as a Clinical Audit rather than a QIP, as it has been performed over an extended period and QIPs are usually performed weekly or even daily.²⁷ Studies in Bangladeshi critical care settings to date have considered only the SOFA, SIRS, APACHE II and SAPS II scoring systems.^28,29 Calibration (correspondence of mortality between index and observed population)³⁰ and validation (formal testing)³⁰ of NEWS2 in the Bangladeshi population & hospital settings are yet to be performed. Effective comparison of data could therefore not be performed.

This QIP however showed that, with adequate education, training, motivation and appropriate modification, the NEWS2 could become a well-accepted, widely adopted, and realistic bedside monitoring tool in resource-limited settings, with a definitely positive outcome in patient care.

Supplemental Material

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Supplemental material, sj-jpg-1-tdo-10.1177_00494755231178124 for Preventing unrecognized deterioration & improving outcomes of critically ill patients using the National Early Warning Score 2 in a high dependency unit in Bangladesh: A quality improvement project by Ahmad Mursel Anam, Adnan Shareef, Farzana Shumy and Matthew Roderick Gerardus King in Tropical Doctor

Supplemental Material

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Supplemental material, sj-jpg-2-tdo-10.1177_00494755231178124 for Preventing unrecognized deterioration & improving outcomes of critically ill patients using the National Early Warning Score 2 in a high dependency unit in Bangladesh: A quality improvement project by Ahmad Mursel Anam, Adnan Shareef, Farzana Shumy and Matthew Roderick Gerardus King in Tropical Doctor

Footnotes

Acknowledgements

This research was undertaken as part of the third year of MSc in Critical Care at the University of Edinburgh.

Declaration of conflicting interests

The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The authors received no financial support for the research, authorship, and/or publication of this article.

ORCID iD

Ahmad Mursel Anam

Supplemental material

Supplemental material for this article is available online.

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