The Prognostic Accuracy of National Early Warning Score 2 on Predicting Clinical Deterioration for Patients With COVID-19: A Systematic Review and Meta-Analysis

Abstract

Background: During the coronavirus disease 2019 (COVID-19) pandemic, the National Early Warning Score 2 (NEWS2) is recommended for the risk stratification of COVID-19 patients, but little is known about its ability to detect severe cases. Therefore, our purpose is to assess the prognostic accuracy of NEWS2 on predicting clinical deterioration for patients with COVID-19.Methods: We searched PubMed, Embase, Scopus, and the Cochrane Library from December 2019 to March 2021. Clinical deterioration was defined as the need for intensive respiratory support, admission to the intensive care unit, or in-hospital death. Sensitivity, specificity, and likelihood ratios were pooled by using the bivariate random-effects model. Overall prognostic performance was summarized by using the area under the curve (AUC). We performed subgroup analyses to assess the prognostic accuracy of NEWS2 in different conditions.Results: Eighteen studies with 6,922 participants were included. The NEWS2 of five or more was commonly used for predicting clinical deterioration. The pooled sensitivity, specificity, and AUC were 0.82, 0.67, and 0.82, respectively. Benefitting from adding a new SpO2 scoring scale for patients with hypercapnic respiratory failure, the NEWS2 showed better sensitivity (0.82 vs. 0.75) and discrimination (0.82 vs. 0.76) than the original NEWS. In addition, the NEWS2 was a sensitive method (sensitivity: 0.88) for predicting short-term deterioration within 72 h.Conclusions: The NEWS2 had moderate sensitivity and specificity in predicting the deterioration of patients with COVID-19. Our results support the use of NEWS2 monitoring as a sensitive method to initially assess COVID-19 patients at hospital admission, although it has a relatively high false-trigger rate. Our findings indicated that the development of enhanced or modified NEWS may be necessary.

Assessment of National Early Warning Score 2 as a Tool to Predict the Outcome of COVID-19 Patients on Admission

“…Our prospective study resolves these shortcomings as it was conducted on a larger sample size, thus reducing the chances of error and allowing more accurate prediction. In the pre-COVID period, a score of 5 to 6 indicated a medium risk of deterioration, while a score of 7 or more indicated a high risk of deterioration as per Royal College of Physicians standards [20]. However, in our study on COVID-19 patients, we found that a NEWS2 cut-off score ≥ 6 on admission had higher risk of mortality.…”

“…The role of NEWS2 in COVID- 19 has not yet been thoroughly investigated, even though it is commonly used in clinical practice. According to the advice of Royal College of Physicians, NEWS2 should be utilized while monitoring COVID-19 patients, although, further evaluation should be made if there is any rise in oxygen requirements [20]. Using NEWS2 will make sure that patients who are worsening or at risk of deterioration are recognized and examined as soon as possible by a qualified clinical decision maker.…”

“…Using NEWS2 will make sure that patients who are worsening or at risk of deterioration are recognized and examined as soon as possible by a qualified clinical decision maker. When evaluating a patient's status, NEWS2 should be used in conjunction with clinical judgment [20]. Some patients who might develop increased oxygen requirements during their course in the hospital, may not have any additional significant increase in the NEWS2 score.…”

“…Some patients who might develop increased oxygen requirements during their course in the hospital, may not have any additional significant increase in the NEWS2 score. However, this must trigger an escalation call to a competent clinician [20].…”

“…The Royal College of Physicians (RCP) has identified NEWS2 as a method for standardizing the evaluation and management of acute illness [19]. The score is based on six physiological parameters: (i) respiratory rate, (ii) oxygen saturation and air or oxygen supplementation, (iii) systolic blood pressure, (iv) temperature, (v) pulse rate, and (vi) consciousness level on the alert, voice, pain, unresponsive (AVPU) scale [20]. NEWS2 was classified into three clinical risk categories by the RCP: low (0-4), medium (5-6), and high (≥ 7) [20].…”