Heads down

Wojner-Alexander, Anne W.; Garami, Zsolt; Chernyshev, Oleg; Alexandrov, Andrei V.

doi:10.1212/01.wnl.0000158284.41705.a5

Cited by 162 publications

(141 citation statements)

References 21 publications

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“…4 Small, nonrandomized studies have indicated that the lying-flat position (i.e., fully supine with the back horizontal and the face upwards) increases blood flow in major arteries 5,6 and improves oxygenation of the brain, 7,8 whereas a sitting-up body position with the head elevated (hereafter referred to as the "sitting-up position") may reduce intracranial pressure in patients with large hemispheric ischemic stroke. 9 Uncertainty over the role of head positioning after acute stroke and the potential risks of cardiopulmonary dysfunction and aspiration pneumonia 10 have led to ambiguous guidelines 11 and variation in clinical practice.…”

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confidence: 99%

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

et al. 2017

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BACKGROUNDThe role of supine positioning after acute stroke in improving cerebral blood flow and the countervailing risk of aspiration pneumonia have led to variation in head positioning in clinical practice. We wanted to determine whether outcomes in patients with acute ischemic stroke could be improved by positioning the patient to be lying flat (i.e., fully supine with the back horizontal and the face upwards) during treatment to increase cerebral perfusion. METHODSIn a pragmatic, cluster-randomized, crossover trial conducted in nine countries, we assigned 11,093 patients with acute stroke (85% of the strokes were ischemic) to receive care in either a lying-flat position or a sitting-up position with the head elevated to at least 30 degrees, according to the randomization assignment of the hospital to which they were admitted; the designated position was initiated soon after hospital admission and was maintained for 24 hours. The primary outcome was degree of disability at 90 days, as assessed with the use of the modified Rankin scale (scores range from 0 to 6, with higher scores indicating greater disability and a score of 6 indicating death). RESULTSThe median interval between the onset of stroke symptoms and the initiation of the assigned position was 14 hours (interquartile range, 5 to 35). Patients in the lying-flat group were less likely than patients in the sitting-up group to maintain the position for 24 hours (87% vs. 95%, P<0.001). In a proportional-odds model, there was no significant shift in the distribution of 90-day disability outcomes on the global modified Rankin scale between patients in the lying-flat group and patients in the sitting-up group (unadjusted odds ratio for a difference in the distribution of scores on the modified Rankin scale in the lying-flat group, 1.01; 95% confidence interval, 0.92 to 1.10; P = 0.84). Mortality within 90 days was 7.3% among the patients in the lying-flat group and 7.4% among the patients in the sitting-up group (P = 0.83). There were no significant betweengroup differences in the rates of serious adverse events, including pneumonia. CONCLUSIONSDisability outcomes after acute stroke did not differ significantly between patients assigned to a lying-flat position for 24 hours and patients assigned to a sitting-up position with the head elevated to at least 30 degrees for 24 hours. (Funded by the

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

et al. 2017

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“…Importantly, this treatment can be applied as soon as an ischemic stroke patient is diagnosed. When head position is reduced from 30° to 0° elevation during the first 24 hours after ischemic onset, the mean flow velocity of MCA (measured using Transcranial Doppler) is increased by 20%, resulting in functional improvement in 15% of patients (NIHSS) (Wojner-Alexander, 2005). Conversely, a decrease in cerebral blood flow was observed by increasing the head position from 0° to 30° or 45° Moraine et al, 2000), with cerebral blood flow determined according to the arteriovenous pressure gradient (Moraine et al, 2000).…”

Section: Augmenting Cerebral Blood Flow Using Head Positioningmentioning

confidence: 99%

Understanding and Augmenting Collateral Blood Flow During Ischemic Stroke

Ramakrishnan¹,

Armitage²,

Winship³

2012

Acute Ischemic Stroke

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“…Typically, a conservative approach is used to achieve "permissive hypertension," allowing the blood pressure to remain relatively high to maximize cerebral blood flow during a period of presumed impaired autoregulation. This approach includes the use of intravenous fluids for volume repletion, cessation of antihypertensive therapy, and keeping the head of the patient's bed flat for a period of time [23]. If a patient had fluctuating neurological symptoms (especially if correlated with relatively hypotensive episodes), then induced hypertension may be considered.…”

Section: Large Artery Atherothromboembolismmentioning

confidence: 99%