Acute Crit Care.  2021 Feb;36(1):46-53. 10.4266/acc.2020.00787.

Development of a prognostic scoring system in patients with pneumonia requiring ventilator care for more than 4 days: a single-center observational study

• Oh Y
• Kang Y
• Lee K

• KMID: 2513253
• DOI: http://doi.org/10.4266/acc.2020.00787

Abstract

Background
The aim of the present study was to develop a prognostic model using demographic characteristics, comorbidities, and clinical variables measured on day 4 of mechanical ventilation (MV) for patients with prolonged acute mechanical ventilation (PAMV; MV for >96 hours).
Methods
Data from 437 patients (70.9% male; median age, 68 years) were obtained over a period of 9 years. All patients were diagnosed with pneumonia. Binary logistic regression identified factors predicting mortality at 90 days after the start of MV. A PAMV prognosis score was calculating ß-coefficient values and assigning points to variables.
Results
The overall 90-day mortality rate was 47.1%. Five factors (age ≥65 years, body mass index <18.5 kg/m², hemato-oncologic diseases as comorbidities, requirement for vasopressors on day 4 of MV and requirement for neuromuscular blocking agents on day 4 of MV) were identified as prognostic indicators. Each factor was valued as +1 point, and used to develop a PAMV prognosis score. This score showed acceptable discrimination (area under the receiver operating characteristic curve of 0.695 for mortality, 95% confidence interval 0.650–0.738, p<0.001), and calibration (Hosmer–Lemeshow chi-square=6.331, with df 7 and p=0.502). The cutoff value for predicting mortality based on the maximum Youden index was ≤2 (sensitivity, 87.5%; specificity, 41.3%). For patients with PAMV scores ≤1, 2, 3 and ≥4, the 90-day mortality rates were 29.2%, 45.7%, 67.9%, and 90.9%, respectively (P<0.001).
Conclusions
Our study developed a PAMV prognosis score for predicting 90-day mortality. Further research is needed to validate the utility of this score.

Keyword

mechanical ventilators; pneumonia; prognosis

Figure

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  Figure 1. Flowchart of recruited and enrolled study participants.

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  Figure 2. Kaplan–Meier survival curves, stratified according to the prolonged acute mechanical ventilation prognosis score (log-rank <0.001). ICU: intensive care unit.

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  Figure 3. Comparison of receiver operating characteristic (ROC) curves for the prolonged acute mechanical ventilation (PAMV) prognosis score, Acute Physiology and Chronic Health Evaluation (APACHE) II score, and Sequential Organ Failure Assessment (SOFA) score for predicting 90-day mortality. For all patients, the areas under the ROC curve (AUCs) for the PAMV prognosis score, SOFA score, and APACHE II score were 0.695 (95% CI, 0.650–0.738; P<0.001), 0.608 (95% CI, 0.561–0.654; P<0.001), and 0.569 (95% CI, 0.521–0.616; P<0.001), respectively. The AUC for the PAMV prognosis score was significantly higher than that of the other two scores (P=0.009 and P=0.001, respectively). CI: confidence interval.

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