Analysis of Noninvasive Ventilation in Subjects With Sepsis and Acute Respiratory Failure

Abstract

BACKGROUND:

Acute respiratory failure is among the sequelae of complications that can develop in response to severe sepsis. Research into sepsis-related respiratory failure has focused on ARDS and invasive mechanical ventilation. We studied the factors associated with success and failure of noninvasive ventilation (NIV) in the treatment of sepsis-related acute respiratory failure.

METHODS:

This retrospective study included 136 subjects with a diagnosis of acute respiratory failure and intrapulmonary or extrapulmonary sepsis who were placed on NIV. Subjects were divided into 2 groups based on the need for intubation from NIV: NIV failure (n = 70) and NIV success (n = 66). Demographic, clinical, and outcome data were collected and compared between groups, with the development of multivariate models to predict NIV failure and mortality.

RESULTS:

The overall NIV failure rate in subjects with a diagnosis of sepsis was 51%. There were no between-group differences in demographic or baseline characteristics. However, there were significant differences in clinical variables, with higher SOFA scores (NIV failure: 6.4 [± 3.0] vs NIV success: 4.9 [± 2.1]; P = .002), 2nd lactate levels (NIV failure: 2.6 [1.7 – 4.3] vs NIV success: 1.9 [1.4 – 2.6] mmol/L; P = .007), and initial NIV ${\mathbf{\text{F}}}_{{\mathbf{\text{IO}}}_{\mathbf{\text{2}}}}$ settings (NIV failure: 0.50 [0.40 – 0.70] vs NIV failure: 0.40 [0.35 – 0.50]; P = .003) in subjects who failed NIV. There were also more subjects in the NIV failure group who had a lactate ≥ 4 mmol/L prior to NIV start compared to those who succeeded on NIV (33% vs 15%, P = .02). At NIV start, subjects in the NIV failure group had lower mean arterial pressure (85 mm Hg [IQR 74–96] vs 91.7 mm Hg [IQR 78–108], P = .042) and Glasgow coma scale scores (14 [IQR 13–15] vs 15 [IQR 14–15], P < .002), while fewer subjects in the NIV failure group received a fluid bolus in the 24 h prior to NIV start (33% vs 53%, P = .02) or had signs of volume overload (36% vs 64%, P < .001). Multivariate analysis indicated that age (odds ratio 1.05 [95% CI 1.01–1.09], P = .02), SOFA score (odds ratio 1.49 [95% CI 1.15–1.94], P = .002), first systolic blood pressure (odds ratio 0.97 [95% CI 0.95–0.99], P = .02), signs of volume overload (odds ratio 0.23 [95% CI 0.07–0.68], P = .008], fluids prior to NIV (odds ratio 0.08 [95% CI 0.02–0.31], P < .001), and initial ${\mathbf{\text{F}}}_{{\mathbf{\text{IO}}}_{\mathbf{\text{2}}}}$ on NIV (odds ratio 1.04 [95% CI 1.01–1.08, P = .002) independently predicted NIV failure with an area under the curve of 0.88. Only NIV failure independently predicted death in multivariate analysis (area under the curve = 0.70).

CONCLUSIONS:

NIV failure in sepsis-related acute respiratory failure was independently predicted by patient acuity, first systolic blood pressure after sepsis alert, initial ${\mathbf{\text{F}}}_{{\mathbf{\text{IO}}}_{\mathbf{\text{2}}}}$ settings on NIV, fluid resuscitation, and signs of volume overload. However, only NIV failure independently predicted death in this cohort of subjects.