Sequential Organ Failure Assessment (SOFA) score for predicting mortality in patients with sepsis in Vietnamese intensive care units: A multicentre, cross-sectional study
Authors: Do Son Ngoc , Dao Co Xuan , Nguyen Tuan Anh , Nguyen My Ha , Pham Dung Thi , Nguyen Nga Thi , Huynh Dai Quang , Ai Hoang Quoc Trong , Van Bui Cuong , Vu Thang Dinh , Bui Ha Nhat , Nguyen Hung Tan , Hoang Hai Bui , Phuong Le Thuy Thi , Bao Nguyen Lien Thi , Duong Phuoc Thien , Nguyen Tuan Dang , Le Vuong Hung , Tra Pham Giang Thi , Huong Bui Giang Thi , Van Bui Tam , Ngoc Pham Thao Thi , Nguyen Chi Van , Nguyen Anh Dat , Phua Jason , Li Andrew , Luong Chinh Quoc 
Published: May 2022

Objectives

To compare the accuracy of the SOFA and APACHE II scores in predicting mortality among ICU patients with sepsis in an LMIC.

Design

A multicentre, cross-sectional study.

Setting

A total of 15 adult ICUs throughout Vietnam.

Participants

We included all patients aged ≥ 18 years who were admitted to ICUs for sepsis and who were still in ICUs from 00:00 hour to 23:59 hour of the specified study days (i.e., 9thJanuary, 3rdApril, 3rdJuly, and 9thOctober of the year 2019).

Primary and secondary outcome measures

The primary outcome was hospital all-cause mortality (hospital mortality). We also defined the secondary outcome as all-cause deaths in the ICU (ICU mortality).

Results

Of 252 patients, 40.1% died in hospitals, and 33.3% died in ICUs. SOFA (AUROC: 0.688 [95% CI: 0.618-0.758]; cut-off value ≥ 7.5; PAUROC<0.001) and APACHE II scores (AUROC: 0.689 [95% CI: 0.622-0.756]; cut-off value ≥ 20.5; PAUROC<0.001) both had a poor discriminatory ability for predicting hospital mortality. However, the discriminatory ability for predicting ICU mortality of SOFA (AUROC: 0.713 [95% CI: 0.643-0.783]; cut-off value ≥ 9.5; PAUROC<0.001) was fair and was better than that of APACHE II score (AUROC: 0.672 [95% CI: 0.603-0.742]; cut-off value ≥ 18.5; PAUROC<0.001). A SOFA score ≥ 8 (adjusted OR: 2.717; 95% CI: 1.371-5.382) and an APACHE II score ≥ 21 (adjusted OR: 2.668; 95% CI: 1.338-5.321) were independently associated with an increased risk of hospital mortality. Additionally, a SOFA score ≥ 10 (adjusted OR: 2.194; 95% CI: 1.017-4.735) was an independent predictor of ICU mortality, in contrast to an APACHE II score ≥ 19, for which this role did not.

Conclusions

In this study, SOFA and APACHE II scores were worthwhile in predicting mortality among ICU patients with sepsis. However, due to better discrimination for predicting ICU mortality, the SOFA was preferable to the APACHE II score in predicting mortality.

Clinical trials registry – India: CTRI/2019/01/016898

Strengths and limitations of this study

An advantage of the present study was data from multi centres, which had little missing data.

Due to the absence of a national registry of intensive care units (ICUs) to allow systematic recruitment of units, we used a snowball method to identify suitable units, which might have led to the selection of centres with a greater interest in sepsis management.

Due to the study’s real-world nature, we did not make a protocol for microbiological investigations. Moreover, we mainly evaluated resources utilized in ICUs; therefore, the data detailing the point-of-care testing and life-sustaining treatments were not available. Additionally, to improve the feasibility of conducting the study in busy ICUs, we opted not to collect data on antibiotic resistance and appropriateness.

Due to our independent variables (e.g., SOFA score that was greater than or equal to the cut-off value) that might be associated with primary outcome only measured upon ICU admission, the mixed-effects logistic regression model could not be used to predict discrete outcome variables measured at two different times, i.e., inside and outside the ICU settings.

Although the sample size was large enough, the confidence interval was slightly wide (±6.03%), which might influence the normal distribution of the sample.