Heparins and Compression Devices are Effective in Preventing VTE in a Mixed Neurosurgical Population
Clinical question: What is the efficacy and safety of LMWH, unfractionated heparin, and mechanical devices in preventing VTE in neurosurgical patients?
Background: Neurosurgical patients are at high risk for VTE, but concerns remain regarding the risk of bleeding complications with the use of LMWH or unfractionated heparin (UFH).
Study design: Meta-analysis of 18 randomized trials and 12 cohort studies.
Setting: Patients undergoing spinal surgery or craniotomy.
Synopsis: Among all patients, the pooled DVT rate was 15.5/100. Use of sequential compression devices (SCD) significantly reduced the risk of DVT compared with placebo (relative risk [RR] 0.41, 95% confidence interval [CI] 0.21-0.78). Subcutaneous LMWH was associated with a significantly reduced risk of DVT compared with CS (RR 0.60, 95% CI 0.44-0.81). No other head-to-head comparisons were associated with significant reductions in VTE risk. After adjusting for potential risk factors for DVT and study design, use of heparins or SCDs was associated with a lower risk of DVT. Intracranial hemorrhage (ICH), minor bleeding, major bleeding, or death was not statistically different between any of the groups, although, after adjustment, LMWH was associated with a slightly increased risk of ICH.
The quality of included studies varied considerably and inter-rater agreement on study quality was low, raising the possibility of study selection bias. Potential publication bias was not addressed. Bleeding complications were rare, so the estimates of risk may be imprecise.
Bottom line: Individualized therapy is required for DVT prophylaxis in the neurosurgical patient; SCDs reduce VTE risk and both pharmacologic and mechanical prophylaxis may be indicated in patients with increased VTE risk.
Citation: Collen JF, Jackson JL, Shorr AF, Moores LK. Prevention of venous thromboembolism in neurosurgery: A metaanalysis. Chest. 2008;13(4):237-249.
SMART-COP Predicts Need for ICU Care in CAP
Clinical question: Can a clinical tool predict the need for critical care in community acquired pneumonia (CAP)?
Background: Clinical tools predicting 30-day mortality in community acquired pneumonia (CAP) exist, but do not accurately identify who will require intensive care unit-level care, such as intensive respiratory or vasosuppressor support (IRVS).
Study design: Prospective multi-center observational study.
Setting: Six hospitals in Australia participating in the Australian Community Acquired Pneumonia Study (ACAPS).
Synopsis: Multivariate analysis of a dataset of 882 episodes of CAP identified eight factors that were associated with the need for IRVS, summarized by the mnemonic “SMART-COP” (Systolic blood pressure, Multilobar chest radiography involvement, low Albumin level, high Respiratory rate, Tachycardia, Confusion, poor Oxygenation, and low arterial pH). Assigning one point for five factors and two points for three factors (systolic blood pressure, poor oxygenation, and low arterial pH) a SMART-COP score >3 identified 92.3% (95% CI 84.8-96.9%) of patients who required IRVS, including 84% who did not initially require ICU care. Specificity was 62.3% (CI 58.8-65.7%). Test characteristics for predicting IRVS were superior to existing prediction rules (PSI and CURB-65).
Most patients were drawn from large, urban teaching hospitals in Australia, so the results may not be generalizable. The authors also presented a modification of SMART-COP, using pulse oximetry rather than blood gas results; this may be even more useful in the pre-hospital setting.
Bottom line: SMART-COP is a reasonable screening tool for predicting need for ICU-level care in patients admitted with CAP.
Citation: Charles PGP, Wolfe, R, Whitby, M, et. al. SMART-COP: a tool for predicting the need for intensive respiratory or vasopressor support in community-acquired pneumonia. Clin Infect Dis. 2008;47(3):375-384.