Association Between Post-Extubation APACHE II Scores and Reintubation

Abstract

Background: Extubation failure is associated with poor clinical outcomes, including increased mortality, longer hospital stays, and higher medical costs. Critical illness scoring systems, such as the APACHE II scores recorded before extubation, have been shown to correlate with extubation outcomes. However, there is a lack of data regarding the role of post-extubation APACHE II scores in predicting extubation outcomes. Therefore, the primary aim of this study was to determine the association between post-extubation APACHE II scores and extubation outcome.

Methods: This was a prospective, cohort study of adult patients that received mechanical ventilation for at least 24 h at an academic medical center from December 2021 and April 2022. The study protocol was approved by the Institutional Review Board. Extubation success was defined as the patient’s ability to sustain independent/spontaneous respiration for up to 72 h post-planned extubation. APACHE II scores were recorded 1 h before extubation, 12, 24, and 48 h after extubation. Chi square or Fisher exact test was used for categorical variables and T-test/Mann-Whitney for continuous variables. A P-value of < .05 was considered statistically significant.

Results: Among 95 included subjects [mean age 62 (SD 14) y; male 49 (51.6%); African American 42 (44.2%); median BMI 29 (IQR 25-34)], 75 (78.9%) had a successful extubation, and 20 (21%) failed extubation. The two study groups did not differ in terms of age, gender, and ethnicity; however, BMI was significantly higher for the failure group (28.07 vs. 31.98 kg/m², P = .037). There was no difference in RSBI at the end of SBT (49 vs. 60, P = .108) between the two groups. Median APACHE II scores at 1 h (13 vs. 13; P = .46) before extubation did not differ between the two groups. However, median APACHE II scores at 12 h (10 vs. 14, P = .004), at 24 h (10 vs. 16, P = .001) and at 48 h (9 vs. 14; P = .01) post extubation were significantly higher in the extubation failure group. The extubation failure group had a higher median duration of mechanical ventilation (47.7 vs. 71.6 h, P = .007), a higher hospital length of stay (15.62 vs. 25.89 d, P = .02), and a higher ICU length of stay (9.79 vs. 20.42 d, P = .004) compared to the extubation success group.

Conclusions: This study result shows that post extubation measurement of APACHE II scores can be useful in determining extubation outcome.