Determinants of Mortality for Ventilated Hospital-Acquired Pneumonia and Ventilator-Associated Pneumonia.

Hospital-acquired pneumonia (HAP) is the most common hospital-acquired infection, accounting for 22% of all nosocomial infections. The available studies to date have not attempted to assess whether confounding factors may account for the observed difference in mortality for the two forms of nosocomial pneumonia associated with mechanical ventilation, namely ventilated HAP (vHAP) and ventilator-associated pneumonia (VAP). OBJECTIVES: To determine if vHAP is an independent predictor of mortality among patients with nosocomial pneumonia. DESIGN SETTING AND PARTICIPANTS: Single-center retrospective cohort study conducted at Barnes-Jewish Hospital, St. Louis, MO, between 2016 and 2019. Adult patients with a pneumonia discharge diagnosis were screened and patients diagnosed with vHAP and VAP were included. All patient data was extracted from the electronic health record. MAIN OUTCOMES AND MEASURES: The primary outcome was 30-day all-cause mortality (ACM). RESULTS: One thousand one-hundred twenty unique patient admissions were included (410 vHAP, 710 VAP). Thirty-day ACM was greater for patients with vHAP compared with VAP (37.1% vs 28.5%; p = 0.003). Logistic regression analysis identified vHAP (adjusted odds ratio [AOR], 1.77; 95% CI, 1.51-2.07), vasopressor use (AOR, 2.34; 95% CI, 1.94-2.82), Charlson Comorbidity Index (1-point increments) (AOR, 1.21; 95% CI, 1.18-1.24), total antibiotic treatment days (1-d increments) (AOR, 1.13; 95% CI, 1.11-1.14), and Acute Physiology and Chronic Health Evaluation II score (1-point increments) (AOR, 1.04; 95% CI, 1.03-1.06) as independent predictors of 30-day ACM. The most common bacterial pathogens identified as causes of vHAP and VAP were Staphylococcus aureus, Enterobacterales species, and Pseudomonas aeruginosa. CONCLUSIONS AND RELEVANCE: In this single-center cohort study with low rates of initial inappropriate antibiotic therapy, vHAP had greater 30-day ACM compared with VAP after adjusting for potential confounding variables including disease severity and comorbidities. This finding suggests that clinical trials enrolling patients with vHAP need to account for this outcome difference in their trial design and data interpretation.

Spectrum scores: Toward a better definition of de-escalation.

Spectrum scores measure antimicrobial utilization while also quantifying the spectrum of activity. Accordingly, changes in spectrum score can be used to identify antimicrobial de-escalation. We show that spectrum-score-based de-escalation has a 95.7% positive percentage agreement and 81.6% negative percentage agreement versus de-escalation defined as stopping either antistaphylococcal or antipseudomonal agents.

The importance of viruses in ventilator-associated pneumonia.

OBJECTIVE: Ventilator-associated pneumonia (VAP) remains a challenge. The importance of viruses in VAP is not established. We sought to determine the prevalence of viruses in VAP and the outcomes of viral VAP. DESIGN: Retrospective study of VAP over 3 years. The frequency of a viral process represented the primary endpoint. Clinical outcomes served as secondary endpoints. We identified variables independently associated with a virus and conducted sensitivity analyses to assess the interaction between type of infection and patient characteristics. SETTING: Tertiary-care referral center. PATIENTS: The final cohort consisted of 710 patients and a virus was isolated in 5.1%. INTERVENTIONS: None. RESULTS: The most common viruses included: rhinovirus, influenza A, and cytomegalovirus. Baseline characteristics were similar between those with and without viral infections. In logistic regression, immunosuppression (adjusted odds ratio [aOR], 2.97; 95% confidence interval [CI], 1.44-6.14) and stem-cell transplantation (SCT, aOR, 3.58; 95% CI, 1.17-10.99) were independently associated with a virus. The presence of either variable performed poorly as a screening test for a virus. In-hospital (22.4% vs 21.6%; P = .869) and 30-day (32.8% vs 27.9%; P = .448) mortality rates were similar between the cohorts, respectively. Sensitivity analyses restricted to patients without a mixed viral and bacterial infection or those who were immunocompetent yielded similar results. CONCLUSION: Although infrequent, a range of viruses may cause VAP. Viruses more often complicate SCT and immunosuppression, but one can isolate viruses in immunocompetent subjects. Viral VAP produces severe infection and results in high mortality rates. Clinical features do not differentiate viral from nonviral VAP.

Impact of Angiotensin-Converting Enzyme Inhibitors and Angiotensin Receptor Blockers on Renal Function in Type 1 Cardiorenal Syndrome.

INTRODUCTION: Angiotensin-converting enzyme inhibitor (ACE-I) and angiotensin receptor blocker (ARB) discontinuation during acute heart failure (AHF) is associated with increased mortality following hospitalization. Although the etiology of acute kidney injury (AKI) in type 1 cardiorenal syndrome (CRS) has been linked to renal venous congestion, ACE-I/ARB withdrawal (AW) theoretically promotes renal function recovery. ACE-I/ARBs are dose-reduced or withheld in approximately half of patients with CRS, but the subsequent impact on renal function remains largely uninvestigated. This study compared AW to ACE-I/ARB continuation (AC) during CRS. METHODS: This was a retrospective, single-center chart review. Patients aged 18-89 years admitted from April 2018 to August 2019 with AHF and AKI were identified using discharge ICD-10 codes. All patients were treated with an ACE-I/ARB before admission. Key exclusion criteria included shock, pregnancy, and end-stage renal disease. The primary endpoint was change in serum creatinine (SCr) from admission through 72 hours. Data were analyzed utilizing chi-square and Mann-Whitney U tests with SPSS software. RESULTS: A total of 111 admissions were included. AW occurred in 68 patients upon admission. AW patients presented with a higher blood urea nitrogen (P = 0.034), higher SCr (P = 0.021), and lower ejection fraction (P = 0.04). Median SCr change from admission to 72 hours did not differ between groups (AW -0.1 mg/dL vs AC 0.0 mg/dL, P = 0.05). There was no difference in SCr reduction ≥0.3 mg/dL at 72 hours, 30-day readmissions, or ACE-I/ARB prescription at discharge. CONCLUSIONS: In patients with type 1 CRS, AW was not associated with improved renal function at 72 hours. A larger sample size is necessary to confirm these results.