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

Abstract

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

Trendelenburg Positioning in Large Vessel Ischaemic Stroke: A Pre-Post Observational Study Using Propensity Score Matching

“…In the absence of superiority of supine (lying flat) position [9], our findings reopen the debate upon the interest of head positioning strategies in the management of acute IS patients. Thus, our findings should encourage large, randomized clinical trials in well-selected populations [10] before TP, an easy-to-use non-pharmacological intervention can be proposed at pre-hospital setting or in non-eligible patients for endovascular thrombectomy.…”

“…A non-pharmacological intervention aimed at modulating cerebral perfusion in the acute phase of IS is head positioning [7,8]. Among the different possible head positions, supine positioning (aka lying flat) has not shown superiority over sitting-up position in terms of reducing disability or mortality in the HeadPoST study, a large pragmatic cluster-randomized crossover trial [9]. However, a major issue could explain this negative finding: most of the patients might not have intracranial occlusion and were not supposed to be improved by head positioning [10].…”

Inter- and intraobserver reliability for angiographic leptomeningeal collateral flow assessment by the American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology (ASITN/SIR) scale

“…These scores may be more advantageous because they truly evaluate the enhancement and extent of collateral vessels in the ischemic territory with direct correlation with CT or MRI signs of ischemic core and penumbra. Such advantages are crucial for research into collateral enhancing strategies, which include induced hypertension, volume expansion, flat head positioning,34 external counterpulsation, partial aortic obstruction diverting splanchnic blood flow to the upper body and brain,35 and sphenopalatine ganglion stimulation 36 37. Large, randomized trials in patients with acute stroke evaluating collateral enhancing strategies have seldom been performed.…”

Acute Ischemic Stroke Management Review for the Hospitalist

“…Elevated blood pressures following an ischemic stroke serve to preserve perfusion to the penumbra and this is the rationale behind pressure augmentation (91). Blood pressure is increased in a step wise manner using IV vasopressors and regular neurological examinations guide escalation end-points as well as weaning of augmentation (39,77,91 it has been thought that keeping the head of the bed as flat as possible might improve cerebral perfusion; however, this theory has been recently challenged (98).…”