OLAVARRIA IANISZEWSKY, VERONICA VIVIANA
Thumbnail Image
Preferred name
OLAVARRIA IANISZEWSKY, VERONICA VIVIANA
Official Name
OLAVARRIA IANISZEWSKY, VERONICA VIVIANA
Main Affiliation
Email
v.olavarria@udd.cl
ORCID
Scopus Author ID
57204794060

Research Output

2021 2021 2020 2020 2019 2019 2018 2018 2017 2017 2016 2016 2015 2015 2014 2014 0.0 0.0 1.0 1.0 2.0 2.0 3.0 3.0 4.0 4.0 5.0 5.0

Filters

20
20
Reset filters

Settings
Now showing 1 - 10 of 20
No Thumbnail Available
Publication

Cluster-Randomized, Crossover Trial of Head Positioning in Acute Stroke

2017 , Craig S. Anderson , Hisatomi Arima , LAVADOS GERMAIN, PABLO MANUEL , Laurent Billot , Maree L. Hackett , OLAVARRIA IANISZEWSKY, VERONICA VIVIANA , MUÑOZ VENTURELLI, PAULA ANDREA , BRUNSER RABOVICH, ALEJANDRO MICHEL , Bin Peng , Liying Cui , Lily Song , Kris Rogers , Sandy Middleton , Joyce Y. Lim , Denise Forshaw , C. Elizabeth Lightbody , Mark Woodward , Octavio Pontes-Neto , H. Asita De Silva , Ruey-Tay Lin , Tsong-Hai Lee , Jeyaraj D. Pandian , Gillian E. Mead , Thompson Robinson , Caroline Watkins

View
No Thumbnail Available
Publication

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 , Hisatomi Arima , Craig S Anderson , OLAVARRIA IANISZEWSKY, VERONICA VIVIANA

Rationale 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. Aim To determine if the lying flat position increases mean CBFV in the affected territory as compared to the sitting up position in AIS patients. Methods and design 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. Study outcomes 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. Sample size estimates 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. Conclusion HeadPoST pilot is a cluster randomized multicenter clinical trial investigating the effect of head positioning on mean CBFV in anterior circulation AIS.

View
No Thumbnail Available
Publication

Influence of Including Patients with Premorbid Disability in Acute Stroke Trials: The HeadPoST Experience

2021 , Xia Wang , Tom J. Moullaali , Menglu Ouyang , Laurent Billot , Else Charlotte Sandset , Lili Song , Candice Delcourt , Maree L. Hackett , Caroline L. Watkins , Thompson G. Robinson , Jie Yang , LAVADOS GERMAIN, PABLO MANUEL , BRUNSER, ALEJANDRO , OLAVARRIA IANISZEWSKY, VERONICA VIVIANA , MUÑOZ VENTURELLI, PAULA ANDREA , Hisatomi Arima , Sandy Middleton , Octávio M. Pontes-Neto , Jeyaraj Durai Pandian , Kris Rogers , Craig S. Anderson

<b><i>Background:</i></b> Patients with premorbid functional impairment are generally excluded from acute stroke trials. We aimed to determine the impact of including such patients in the Head Positioning in acute Stroke Trial (HeadPoST) and early additional impairment on outcomes. <b><i>Methods:</i></b> Post hoc analyses of HeadPoST, an international, cluster-randomized crossover trial of lying-flat versus sitting-up head positioning in acute stroke. Associations of early additional impairment, defined as change in modified Rankin scale (mRS) scores from premorbid levels (estimated at baseline) to Day 7 (“early ΔmRS”), and poor outcome (mRS score 3–6) at Day 90 were determined with generalized linear mixed model. Heterogeneity of the trial treatment effect was tested according to premorbid mRS scores 0–1 versus 2–5. <b><i>Results:</i></b> Of 8,285 patients (38.9% female, mean age 68 ± 13 years) with complete data, there were 1,984 (23.9%) with premorbid functional impairment (mRS 2–5). A significant linear association was evident for early ∆mRS and poor outcome (per 1-point increase in ΔmRS, adjusted odds ratio 1.20, 95% confidence interval 1.14–1.27; <i>p</i> &#x3c; 0.0001). Patients with greater premorbid functional impairment were less likely to develop additional impairment, but their risk of poor 90-day outcome significantly increased with increasing (worse) premorbid mRS scores (linear trend <i>p</i> &#x3c; 0.0001). There was no heterogeneity of the trial treatment effect by level of premorbid function. <b><i>Conclusions:</i></b> Early poststroke functional impairment that exceeded premorbid levels was associated with worse 90-day outcome, and this association increased with greater premorbid functional impairment. Yet, including premorbid impaired patients in the HeadPoST did not materially affect the subsequent treatment effect. <b><i>Clinical Trial Registration:</i></b> HeadPoST is registered at http://www.ClinicalTrials.gov (NCT02162017).

View
No Thumbnail Available
Publication

Quantifying regional variations in components of acute stroke unit (ASU) care in the international HeadPoST study

2020 , Menglu Ouyang , Yao Zhang , Xia Wang , Lili Song , Laurent Billot , Thompson Robinson , LAVADOS GERMAIN, PABLO MANUEL , Hisatomi Arima , Maree L. Hackett , OLAVARRIA IANISZEWSKY, VERONICA VIVIANA , MUÑOZ VENTURELLI, PAULA ANDREA , Sandy Middleton , Caroline L. Watkins , Octavio M. Pontes-Neto , Tsong-Hai Lee , BRUNSER, ALEJANDRO , Craig S. Anderson

View
No Thumbnail Available
Publication

Prognostic significance of early urinary catheterization after acute stroke: Secondary analyses of the international HeadPoST trial

2020 , Menglu Ouyang , Laurent Billot , Lili Song , Xia Wang , Christine Roffe , Hisatomi Arima , LAVADOS GERMAIN, PABLO MANUEL , Maree L Hackett , OLAVARRIA IANISZEWSKY, VERONICA VIVIANA , MUÑOZ VENTURELLI, PAULA ANDREA , Sandy Middleton , Octavio M Pontes-Neto , Tsong-Hai Lee , Caroline L Watkins , Thompson G Robinson , Craig S Anderson

Background An indwelling urinary catheter (IUC) is often inserted to manage bladder dysfunction, but its impact on prognosis is uncertain. We aimed to determine the association of IUC use on clinical outcomes after acute stroke in the international, multi-center, cluster crossover, Head Positioning in Acute Stroke Trial (HeadPoST). Methods Data were analyzed on HeadPoST participants (n = 11,093) randomly allocated to the lying-flat or sitting-up head position. Binomial, logistic regression, hierarchical mixed models were used to determine associations of early insertion of IUC within seven days post-randomization and outcomes of death or disability (defined as “poor outcome,” scores 3–6 on the modified Rankin scale) and any urinary tract infection at 90 days with adjustment of baseline and post-randomization management covariates. Results Overall, 1167 (12%) patients had an IUC, but the frequency and duration of use varied widely across patients in different regions. IUC use was more frequent in older patients, and those with vascular comorbidity, greater initial neurological impairment (on the National Institutes of Health Stroke Scale), and intracerebral hemorrhage as the underlying stroke type. IUC use was independently associated with poor outcome (adjusted odds ratio (aOR): 1.40, 95% confidence interval (CI): 1.13–1.74), but not with urinary tract infection after adjustment for antibiotic treatment and stroke severity at hospital separation (aOR: 1.13, 95% CI: 0.59–2.18). The number exposed to IUC for poor outcome was 13. Conclusions IUC use is associated with a poor outcome after acute stroke. Further studies are required to inform appropriate use of IUC.

View
No Thumbnail Available
Publication

Regional variation in acute stroke care organisation

2016 , MUÑOZ VENTURELLI, PAULA ANDREA , Thompson Robinson , LAVADOS GERMAIN, PABLO MANUEL , OLAVARRIA IANISZEWSKY, VERONICA VIVIANA , Hisatomi Arima , Laurent Billot , Maree L. Hackett , Joyce Y. Lim , Sandy Middleton , Octavio Pontes-Neto , Bin Peng , Liying Cui , Lily Song , Gillian Mead , Caroline Watkins , Ruey-Tay Lin , Tsong-Hai Lee , Jeyaraj Pandian , H. Asita de Silva , Craig S. Anderson

View
No Thumbnail Available
Publication

Head Position in Stroke Trial (HeadPoST) - sitting-up vs lying-flat positioning of patients with acute stroke: study protocol for a cluster randomised controlled trial

2015 , MUÑOZ VENTURELLI, PAULA ANDREA , Hisatomi Arima , LAVADOS GERMAIN, PABLO MANUEL , BRUNSER, ALEJANDRO , Bin Peng , Liying Cui , Lily Song , Laurent Billot , Elizabeth Boaden , Maree L. Hackett , Stephane Heritier , Stephen Jan , Sandy Middleton , OLAVARRIA IANISZEWSKY, VERONICA VIVIANA , Joyce Y. Lim , Richard I. Lindley , Emma Heeley , Thompson Robinson , Octavio Pontes-Neto , Lkhamtsoo Natsagdorj , Ruey-Tay Lin , Caroline Watkins , Craig S. Anderson

View
No Thumbnail Available
Publication

Low blood pressure and adverse outcomes in acute stroke: HeadPoST study explanations

2020 , Menglu Ouyang , MUÑOZ VENTURELLI, PAULA ANDREA , Laurent Billot , Xia Wang , Lili Song , Hisatomi Arima , LAVADOS GERMAIN, PABLO MANUEL , Maree L. Hackett , OLAVARRIA IANISZEWSKY, VERONICA VIVIANA , BRUNSER, ALEJANDRO , Sandy Middleton , Octavio M. Pontes-Neto , Tsong-Hai Lee , Caroline L. Watkins , Thompson Robinson , Craig S. Anderson

View
No Thumbnail Available
Publication

Head Position in the Early Phase of Acute Ischemic Stroke: An International Survey of Current Practice

2015 , MUÑOZ VENTURELLI, PAULA ANDREA , OLAVARRIA IANISZEWSKY, VERONICA VIVIANA , RECULE GONZALEZ, FRANCISCA , Hisatomi Arima , BRUNSER, ALEJANDRO , Craig S. Anderson , LAVADOS GERMAIN, PABLO MANUEL

View
No Thumbnail Available
Publication

No benefit of flat head positioning in early moderate–severe acute ischaemic stroke: a HeadPoST study subgroup analysis

2020 , BRUNSER, ALEJANDRO , Menglu Ouyang , Hisatomi Arima , Pablo M Lavados , Thompson Robinson , MUÑOZ VENTURELLI, PAULA ANDREA , Verónica V Olavarría , Laurent Billot , Marre L Hackett , Lili Song , Sandy Middleton , Octavio Pontes-Neto , Tsong-Hai Lee , Caroline Watkins , Craig S Anderson

BackgroundAlthough the Head Positioning in acute Stroke Trial (HeadPoST) showed no effect of the flat head position (FP; vs sitting up head position (SUP)) on functional outcome, we hypothesised that it could still offer benefits if commenced early in those with acute ischaemic stroke (AIS) of at least moderate severity.MethodsSubgroup analysis of HeadPoST in participants with National Institutes of Health Stroke Scale (NIHSS) scores ≥7, ≥10 and ≥14, randomised to FP or SUP <4.5 hours of AIS onset on functional outcomes defined by a shift in scores on the modified Rankin scale (mRS) and death/disability (mRS scores 3–6), and any cardiovascular serious adverse event. Logistic regression analyses were undertaken adjusted for study design and baseline risk factors.ResultsThere was no significant differential treatment effect in patient subgroups defined by increasing baseline NIHSS scores: adjusted OR and 95% CI for ordinal shift and binary (3–6) mRS scores: for NIHSS ≥7 (n=867) 0.92 (0.67 to 1.25) and 0.74 (0.52 to 1.04); NIHSS ≥ 10 (n=606) 0.80 (0.58 to 1.10) and 0.77 (0.49 to 1.19); NIHSS ≥14 (n=378) 0.82 (0.54 to 1.24) and 1.22 (0.69 to 2.14).ConclusionsEarly FP had no significant effect in patients with moderate–severe AIS.Trial registration numberNCT02162017.

View