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    Scopus© Citations 2  1
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    Changes in cerebral blood flow velocity in supine and sitting position in patients with aneurysmal subarachnoid hemorrhage
    (2014)
    CATALINA MARIA MERINO OSORIO
    ;
    Pía Heap
    ;
    Valentina Vergara
    ;
    Alonso Yáñez
    ;
    Rodrigo Rivera
      2Scopus© Citations 2
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    Head position and cerebral blood flow in acute ischemic stroke patients: Protocol for the pilot phase, cluster randomized, Head Position in Acute Ischemic Stroke Trial (HeadPoST pilot)
    (2016)
    BRUNSER, ALEJANDRO  
    ;
    MUÑOZ VENTURELLI, PAULA ANDREA  
    ;
    LAVADOS GERMAIN, PABLO MANUEL  
    ;
    Javier Gaete
    ;
    Sheila Martins
    <jats:sec><jats:title>Rationale</jats:title><jats:p> Few proven interventions exist for acute ischemic stroke (AIS), and most are expensive and restricted in applicability. Lying flat ‘head down’ positioning of AIS patients has been shown to increase by as much as 20%, mean cerebral blood flow velocities (CBFV) measured by transcranial Doppler (TCD) but whether this translates into clinical improvement is uncertain. </jats:p></jats:sec><jats:sec><jats:title>Aim</jats:title><jats:p> To determine if the lying flat position increases mean CBFV in the affected territory as compared to the sitting up position in AIS patients. </jats:p></jats:sec><jats:sec><jats:title>Methods and design</jats:title><jats:p> Head Position in Acute Ischemic Stroke Trial (HeadPoST pilot) is a cluster randomized (clusters being months), assessor-blinded end-point, phase IIb trial, where consecutive adults with anterior circulation AIS within 12 h of symptom onset are positioned to a randomized position for 48 h with TCD performed serially. </jats:p></jats:sec><jats:sec><jats:title>Study outcomes</jats:title><jats:p> Primary outcome is mean CBFV on TCD at 1 and 24 h after positioning. Secondary outcomes include: serious adverse events, neurological impairment at seven days, and death and disability at 90 days. </jats:p></jats:sec><jats:sec><jats:title>Sample size estimates</jats:title><jats:p> Assuming an increase of 8.3 (SD 11.4) cm/s in average of mean CBFV when tilted from 30° to 0°, 46 clusters are required (92 patients in total) to detect a 20% increase of mean CBFV with 90% power and 5% level of significance. </jats:p></jats:sec><jats:sec><jats:title>Conclusion</jats:title><jats:p> HeadPoST pilot is a cluster randomized multicenter clinical trial investigating the effect of head positioning on mean CBFV in anterior circulation AIS. </jats:p></jats:sec>
    Scopus© Citations 11  3
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    Head Position and Cerebral Blood Flow Velocity in Acute Ischemic Stroke: A Systematic Review and Meta-Analysis
    (2014)
    OLAVARRIA IANISZEWSKY, VERONICA VIVIANA  
    ;
    Hisatomi Arima
    ;
    Craig S. Anderson
    ;
    BRUNSER, ALEJANDRO  
    ;
    MUÑOZ VENTURELLI, PAULA ANDREA  
    <jats:p>&lt;b&gt;&lt;i&gt;Background:&lt;/i&gt;&lt;/b&gt; Patients with acute ischemic stroke (AIS) have impaired vasomotor reactivity, especially in the affected cerebral hemisphere, such that they may depend directly on systemic blood pressure to maintain perfusion to vulnerable ‘at risk' penumbral tissue. As the sitting up position may affect cerebral perfusion by decreasing cerebral blood flow (CBF) in salvageable tissue, positioning AIS patients with their head in a lying flat position could increase CBF through collateral circulation or gravitational force. We wished to quantify the effect of different head positions on mean flow velocity (MFV) by transcranial Doppler ultrasonography (TCD) in AIS patients to assess the potential for benefit (or harm) of head positioning in a clinical trial. &lt;b&gt;&lt;i&gt;Methods:&lt;/i&gt;&lt;/b&gt; We performed a systematic review and meta-analysis of observational studies with TCD to evaluate differences in cerebral MFV between the lying flat and sitting up head positions in AIS. For each study and each comparison, we obtained the mean value of changes in MFV and its variance. &lt;b&gt;&lt;i&gt;Results:&lt;/i&gt;&lt;/b&gt; A total of 303 studies were identified, but 298 were excluded for varying reasons; 4 papers met the inclusion criteria and 57 patients were included in the meta-analysis for calculation of the overall mean difference in MFV. We found a significant increase in MFV from a bed angle of 30 to 15° (4.6 cm/s, 95% confidence interval, CI, 2.9-6.2, p &lt; 0.001) and from 30 to 0° (8.3 cm/s, 95% CI 5.3-11.3, p &lt; 0.001) in the affected hemisphere but not on the normal side in AIS patients. &lt;b&gt;&lt;i&gt;Conclusions:&lt;/i&gt;&lt;/b&gt; In AIS patients, MFV increased significantly in the side affected by the stroke but not in the unaffected side when they were positioned in a lying flat head position at 0 or 15° compared to an upright head position at 30°. The clinical significance of these findings is now undergoing further randomized evaluation in the international multicenter Head Position in Acute Stroke Trial (HeadPoST).</jats:p>
    Scopus© Citations 97  1
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    Managing All the Genotypic Knowledge: Approach to a Septic Patient Colonized by Different Enterobacteriales with Unique Carbapenemases
    (2019)
    Stacy C. Park
    ;
    Alexander M. Wailan
    ;
    Katie E. Barry
    ;
    Kasi Vegesana
    ;
    Joanne Carroll
    <jats:p> The recent development of new antimicrobials active against carbapenemase-producing <jats:italic>Enterobacteriales</jats:italic> (CPE) has brought new hope for the treatment of infections due to these organisms. However, the evolving epidemiology of bacteria with carbapenemases may complicate management, as providers are faced with treating patients colonized by bacteria producing multiple carbapenemases. </jats:p>
    Scopus© Citations 7  1