Daily Ards Research Analysis
Across three ICU-focused cohort analyses, ventilator and infection-management insights emerged. Higher PEEP at extubation in acute brain injury predicted extubation failure and ICU mortality but likely reflected underlying ARDS severity. Infections with multiple bloodstream pathogens did not worsen adjusted outcomes versus monomicrobial infections, and in burn-related ARDS, HFNC showed feasibility as initial support compared with mechanical ventilation, though confounding by burn severity persis
Summary
Across three ICU-focused cohort analyses, ventilator and infection-management insights emerged. Higher PEEP at extubation in acute brain injury predicted extubation failure and ICU mortality but likely reflected underlying ARDS severity. Infections with multiple bloodstream pathogens did not worsen adjusted outcomes versus monomicrobial infections, and in burn-related ARDS, HFNC showed feasibility as initial support compared with mechanical ventilation, though confounding by burn severity persists.
Research Themes
- Extubation readiness and PEEP as a prognostic marker in neurocritical care
- Impact of polymicrobial versus monomicrobial bloodstream infections on ICU outcomes
- Feasibility of HFNC as initial support in burn-related ARDS
Selected Articles
1. Associations of positive end-expiratory pressure (PEEP) with extubation failure and clinical outcomes in invasively ventilated patients with acute brain injury: A secondary analysis of the ENIO study.
In a secondary analysis of 1154 invasively ventilated ABI patients, higher PEEP measured early and at extubation was associated with extubation failure and ICU mortality. After adjusting for ARDS, PEEP was no longer independently associated, suggesting it functions as a surrogate of underlying lung pathology and extubation readiness.
Impact: Clarifies that PEEP at extubation signals risk but likely reflects disease severity rather than a modifiable target, informing extubation decisions in neurocritical care.
Clinical Implications: Use PEEP as part of a holistic extubation-readiness assessment in ABI (e.g., gas exchange, ARDS status, respiratory mechanics), rather than attempting to lower PEEP alone to enable extubation.
Key Findings
- Extubation failure occurred in 21.2% and ICU mortality was 3.7% among 1154 ABI patients.
- Higher PEEP at days 1, 3, and 7 was associated with extubation failure (OR=1.13; 95%CI 1.01–1.26).
- At extubation, higher PEEP correlated with extubation failure (OR=1.13) and ICU mortality (HR=1.38); these associations lost significance after adjusting for ARDS, which independently predicted failure.
Methodological Strengths
- Large, multicenter cohort with predefined timepoints for PEEP assessment (days 1, 3, 7, and extubation).
- Robust multivariable modeling (logistic and Cox regression) with sensitivity analyses adjusting for ARDS.
Limitations
- Post-hoc observational design susceptible to residual confounding and indication bias.
- Lack of standardized extubation protocols and potential variability in PEEP titration across centers.
Future Directions: Prospective studies integrating PEEP with ARDS status, respiratory mechanics, and gas exchange into validated extubation-readiness scores for ABI patients.
BACKGROUND: Invasive mechanical ventilation (IMV) is crucial for managing acute brain injury (ABI) patients, yet the effects of positive end-expiratory pressure (PEEP) on outcomes are not well understood. This study aimed to evaluate the relationship between PEEP levels and risk of extubation failure as well as intensive care unit (ICU) mortality in ABI patients. METHODS: This post-hoc analysis of the ENIO study included 1512 ABI patients from the ENIO cohort, excluding those without available data on PEEP at day 1 and who never received an extubation trial. PEEP levels were recorded at days 1, 3, 7, and on the day of extubation. Logistic regression assessed the association between PEEP and extubation failure, while Cox proportional hazards regression analyzed ICU mortality. RESULTS: Among 1154 included patients, extubation failure occurred in 21.2 % and ICU mortality was 3.7 %. Higher median PEEP at days 1, 3, and 7 was independently associated with increased odds ratio (OR) of extubation failure (OR = 1.13; 95 %CI = 1.01-1.26; p = 0.0294). At the time of extubation, higher PEEP was also significantly associated with extubation failure (OR = 1.13; 95 %CI = 1.02-1.25; p = 0.0218) and ICU mortality (Hazard Ratio, HR = 1.38; 95 %CI = 1.12-1.69; p = 0.0026). However, at sensitivity analyses adjusted for acute respiratory distress syndrome (ARDS), PEEP was no longer significantly associated with outcomes, while ARDS itself was an independent predictor of extubation failure. CONCLUSIONS: Extubating ABI patients at higher PEEP levels was associated with an increased risk of extubation failure and ICU mortality. However, this association likely reflects underlying respiratory pathology or disease severity. Our findings suggest that PEEP level may serve as a surrogate marker for extubation readiness, rather than a modifiable risk factor, and highlight the need for individualized assessment prior to extubation.
2. Clinical and Microbiological Outcomes of Critically Ill Patients With Monomicrobial Versus Polymicrobial Bacterial Bloodstream Infections: A Retrospective Cohort Study.
In 3197 ICU patients with bloodstream infections, polymicrobial episodes did not worsen adjusted 90-day mortality or secondary outcomes, including ARDS at 7 days, compared with monomicrobial infections. Findings were robust after excluding common skin commensals.
Impact: Provides large-scale, methodologically robust evidence that polymicrobial bacteremia does not inherently confer worse ICU outcomes, informing antimicrobial and source-control strategies.
Clinical Implications: Polymicrobial growth alone should not drive escalation of care or pessimistic prognostication; management should remain guided by pathogen profiles, source control, and patient physiology.
Key Findings
- Adjusted 90-day mortality was similar: monomicrobial 28.3% vs polymicrobial 31.1% (risk difference 2.84%; 95%CI −1.19 to 6.88).
- Secondary outcomes showed no significant differences: 30-day mortality, microbiological failure (4.67% vs 6.56%), ECMO initiation (3.65% vs 2.99%), ARDS at 7 days (17.4% vs 15.7%), fever, ICU and hospital length of stay.
- Results remained consistent when excluding common skin commensals, supporting robustness against contamination bias.
Methodological Strengths
- Very large cohort with decade-long inclusion and advanced adjustment (inverse-probability weighting, covariate-adjusted GLMs).
- Sensitivity analysis excluding common skin commensals to mitigate contamination bias.
Limitations
- Retrospective observational design with potential residual confounding and misclassification.
- Heterogeneity in infection sources, source control, and antimicrobial regimens not fully accounted for.
Future Directions: Prospective studies to delineate when polymicrobial findings should alter management, incorporating pathogen interactions, source control quality, and host response.
BACKGROUND: The impact of polymicrobial bloodstream infections in critically ill patients is uncertain. METHODS: This observational cohort study included patients admitted to the ICU for ≥3d. We compared patients with monomicrobial versus polymicrobial (ie, ≥1 positive blood culture with ≥2 isolates) bloodstream infections. Inverse-probability weighting and covariate-adjusted generalized linear regression models were used to calculate adjusted differences in risks and means. The primary outcome was 90-day all-cause mortality from index culture. Secondary outcomes included 30-day all-cause mortality, microbiological failure, ECMO at 30 days, ARDS at 7 days, fever at 7 days, length of ICU and hospital stay. A separate analysis was performed excluding common skin commensals. RESULTS: Between 03/2014 and 03/2024, 3197 patients were included in the overall and 1669 in the common commensal-free cohort. In the overall cohort, 90-day mortality occurred in 749 (28.3%, adjusted 28.3%) of 2648 patients in the monomicrobial group and 164 (29.9%, adjusted 31.1%) of 549 patients in the polymicrobial group (adjusted risk difference, 2.84% [95%CI, -1.19-6.88]). All-cause 30-day mortality, microbiological failure (adjusted, 4.67% vs 6.56%), initiation of ECMO (adjusted, 3.65% vs 2.99%), ARDS (adjusted, 17.4% vs 15.7%), fever (adjusted, 19.1% vs 20.4%), length of ICU stay (adjusted means, 19.6 vs 19.8 days), and length of hospital stay (adjusted means, 42.6 vs 45.2 days) did not differ significantly between the groups. Outcomes did not differ in the common commensal-free cohort. CONCLUSIONS: Clinical and microbiological outcomes were comparable between critically ill patients with monomicrobial and polymicrobial bloodstream infections, regardless of whether suspected contaminants were excluded.
3. High-Flow Nasal Cannula Oxygen Therapy Versus Mechanical Ventilation For Burn Patients With Acute Respiratory Distress Syndrome.
In 124 adults with burn-related ARDS, initial HFNC support showed similar mortality, length of stay, and costs compared with mechanical ventilation despite higher baseline burn severity in the MV group. Findings suggest HFNC is a feasible initial option, though confounding by indication limits causal inference.
Impact: Addresses a critical evidence gap for noninvasive support in burn-related ARDS, informing triage and early respiratory support strategies.
Clinical Implications: HFNC can be considered as an initial support modality in selected burn ARDS patients with close monitoring and clear criteria for escalation to invasive ventilation.
Key Findings
- MV group had greater burn severity: TBSA 69% vs 45% (p=0.043), full-thickness burns 33.5% vs 25% (p=0.012), ABSI/PBI higher (all p<0.001).
- Worst pre-treatment P/F ratio was similar (MV 170 vs HFNC 183; p=0.235).
- Mortality numerically higher with MV (13.58% vs 6.98%; p=0.269), with no significant differences in hospital length of stay or total costs.
Methodological Strengths
- Direct comparison of HFNC versus MV in a defined burn-related ARDS cohort.
- Inclusion of physiologic (P/F ratio) and economic outcomes alongside mortality.
Limitations
- Retrospective design with substantial confounding by indication and baseline severity imbalance.
- Modest sample size, especially in the HFNC group, limits statistical power and generalizability.
Future Directions: Prospective trials to define patient selection, escalation thresholds, and failure criteria for HFNC in burn-related ARDS.
Acute respiratory distress syndrome (ARDS) is a major cause of mortality in patients with severe burns. High-flow nasal cannula (HFNC) and mechanical ventilation (MV) are the primary respiratory support modalities used in these cases. Nevertheless, comparative evidence on their effectiveness in adults with burn-related ARDS remains scarce. This retrospective cohort study included 124 burn patients diagnosed with ARDS between January 2016 and December 2023. Participants were classified into either an MV (n = 81) or an HFNC (n = 43) group according to the initial respiratory support they received. We analyzed demographic information, burn characteristics, physiological parameters, and clinical outcomes. The MV group exhibited significantly more severe burns, as indicated by a larger total burn surface area (69% vs. 45%, p=.043), a greater full-thickness burn area (33.5% vs. 25%, p=.012), and higher ABSI and PBI scores (all p<.001). However, the worst pre-treatment P/F ratio did not differ significantly between groups (MV 170.00 vs. HFNC 183, p=.235). A numerical difference in mortality was observed, with higher rates in the MV group (13.58%) than in the HFNC group (6.98%), though this difference was not statistically significant (p=.269). No significant differences were found in length of hospital stay or total medical costs. These results indicate that HFNC may represent a feasible alternative to MV for providing initial respiratory support in burn patients with ARDS.