Risk factors for ventilator-associated events: a case-control multivariable analysis.

OBJECTIVES: The Centers for Disease Control and Prevention recently released new surveillance definitions for ventilator-associated events, including the new entities of ventilator-associated conditions and infection-related ventilator-associated complications. Both ventilator-associated conditions and infection-related ventilator-associated complications are associated with prolonged mechanical ventilation and hospital death, but little is known about their risk factors and how best to prevent them. We sought to identify risk factors for ventilator-associated conditions and infection-related ventilator-associated complications. DESIGN: Retrospective case-control study. SETTING: Medical, surgical, cardiac, and neuroscience units of a tertiary care teaching hospital. PATIENTS: Hundred ten patients with ventilator-associated conditions matched to 110 controls without ventilator-associated conditions on the basis of age, sex, ICU type, comorbidities, and duration of mechanical ventilation prior to ventilator-associated conditions. INTERVENTIONS: None. MEASUREMENTS: We compared cases with controls with regard to demographics, comorbidities, ventilator bundle adherence rates, sedative exposures, routes of nutrition, blood products, fluid balance, and modes of ventilatory support. We repeated the analysis for the subset of patients with infection-related ventilator-associated complications and their controls. MAIN RESULTS: Case and control patients were well matched on baseline characteristics. On multivariable logistic regression, significant risk factors for ventilator-associated conditions were mandatory modes of ventilation (odds ratio, 3.4; 95% CI, 1.6-8.0) and positive fluid balances (odds ratio, 1.2 per L positive; 95% CI, 1.0-1.4). Possible risk factors for infection-related ventilator-associated complications were starting benzodiazepines prior to intubation (odds ratio, 5.0; 95% CI, 1.3-29), total opioid exposures (odds ratio, 3.3 per 100 µg fentanyl equivalent/kg; 95% CI, 0.90-16), and paralytic medications (odds ratio, 2.3; 95% CI, 0.79-80). Traditional ventilator bundle elements, including semirecumbent positioning, oral care with chlorhexidine, venous thromboembolism prophylaxis, stress ulcer prophylaxis, daily spontaneous breathing trials, and sedative interruptions, were not associated with ventilator-associated conditions or infection-related ventilator-associated complications. CONCLUSIONS: Mandatory modes of ventilation and positive fluid balance are risk factors for ventilator-associated conditions. Benzodiazepines, opioids, and paralytic medications are possible risk factors for infection-related ventilator-associated complications. Prospective studies are needed to determine if targeting these risk factors can lower ventilator-associated condition and infection-related ventilator-associated complication rates.

The new and old definitions of acute myocardial infarction: a data-based comparison.

PURPOSE: To measure the agreement between the newer European Society of Cardiology-American College of Cardiology (ESC-ACC) definition of acute myocardial infarction (AMI) and the traditional definition established by the World Health Organization (WHO). BASIC PROCEDURES: All adult ED patients admitted to our institution with at least one abnormally elevated cardiac biomarker were determined to have had an AMI by either or both definitions. The degree of agreement and the frequency of the reasons for disagreement between these 2 definitions were measured. MAIN FINDINGS: A final study population consisted of 339 patients; 196 (58%) had an AMI by one or both definitions. Among them, 126 (64%; 95% confidence interval [CI], 57-71) were discordant for these 2 definitions: 104 (53%; 95% CI, 46-60) met only the ESC-ACC, whereas 22 (11%; 95% CI, 6-16) met only the WHO definition. Among those who met only the ESC-ACC definition, 37 (36%; 95% CI, 27-45) met none of the 3 traditional WHO criteria. PRINCIPAL CONCLUSIONS: More patients are discordant than concordant for the 2 standard definitions of AMI. Among them, a large majority meet only the new ESC-ACC definition.