Citation: Melloni C, Alexander KP, Chen AY et al. Unfractionated heparin dosing and risk of major bleeding in non-ST-segment elevation acute coronary syndromes. Am Heart J. 2008;156(2):209-215.
Elevated BNP Level Is a Marker for Higher Risk of Adverse Outcomes in Patients with Pulmonary Embolism
Clinical Question: Can elevated BNP levels predict adverse outcomes in patients with acute pulmonary embolism (PE)?
Background: Plasma brain natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP) often are elevated in patients with PE and right ventricular (RV) dysfunction. The finding of RV dysfunction on echocardiography is an indicator of poor outcome in these patients. The role of BNP levels to differentiate patients with PE who are at higher risk of adverse events and poor clinical outcomes has not been determined.
Study Design: Meta analysis of prospective studies.
Settings: 13 studies involving 1,132 patients.
Synopsis: Elevated levels of BNP or NT-pro-BNP were noted in 51% of patients with acute PE. These patients had a higher rate of complicated inpatient course, as well as a higher risk of 30-day mortality (odds ratio 6.8; 95% CI 4.4-10; odds-ratio 7.6; 95% CI 3.4-17). Additionally, increased BNP levels were significantly associated with RV dysfunction (p<0.0001).
While elevated BNP levels may serve as a marker for increased risk of adverse outcomes, the investigators stress these levels alone should not be used to pursue more aggressive treatment strategies. Elevation of these markers is nonspecific and can be secondary to pre-existing heart, lung, or kidney disease, or older age. Further studies are needed to determine the role of BNP in risk stratifying patients with acute PE to different forms of therapy.
Bottom Line: High BNP or NT-pro-BNP levels can differentiate patients with PE who are at a higher risk of complicated hospital course and short-term mortality.
Citation: Klok FA, Mos IC, Huisman MV. Brain-type natriuretic peptide levels in the prediction of adverse outcome in patients with pulmonary embolism: a systematic review and meta-analysis. Am J Respir Crit Care Med 2008;178:425-430.
Silver-Coated Endotracheal Tubes Reduce Incidence of Ventilator-Associated Pneumonia (VAP)
Clinical Question: Can silver-coated endotracheal tubes reduce the incidence of VAP?
Background: Given the high morbidity linked to VAP, prevention strategies have been sought. Silver has broad-spectrum antimicrobial activity in vitro. Thus, a silver-coated endotracheal tube (ET) was designed to help prevent biofilm formation and bacterial colonization.
Study Design: A prospective, randomized, single-blind, controlled study.
Settings: 54 centers in North America.
Synopsis: Out of 9,417 potentially eligible patients, 2,003 patients expected to require mechanical ventilation for 24 hours or longer were randomized to undergo intubation with endotracheal tubes with and without silver coating. The primary outcome was incidence of VAP based on quantitative culture of bronchoalveolar lavage fluid.
The rate of microbiologically confirmed VAP in patients intubated for 24 hours or longer with the silver-coated ET tube was 4.8%, as compared to 7.5% in the control group. Using silver-coated ET tubes resulted in a 35.9% relative risk reduction of VAP incidence. Furthermore, the silver-coated ET tube was associated with a delayed time to VAP occurrence. Other outcomes, including length of intubation, duration of hospital stay, mortality, and frequency of adverse events, however, did not show statistically significant differences between the two groups.
Bottom Line: Using a silver-coated ET tube reduces the incidence of VAP, as well as delays time to VAP occurrence.
Citation: Kollef MH, Afessa B, Anzueta A, et al. Silver-coated endotracheal tubes and incidence of ventilator-associated pneumonia: the NASCENT randomized trial. JAMA. 2008;300:805-813.