HOBOE (Head-of-Bed Optimization of Elevation) Study: association of higher angle with reduced cerebral blood flow velocity in acute ischemic stroke. May, 2012
Head position for acute stroke
For the pragmatic, cluster-randomized, crossover HeadPoST trial, researchers analyzed data from 11,093 patients (mean age, 68 years; 40% women) with acute stroke. Patients were assigned a lying-flat (n = 5,295) or sitting-up position (n = 5,798) in the ED and maintained the position for 24 hours. The patient’s head was elevated at least 30° for the sitting-up position. Patients were followed up at 90 days through phone interview.
The primary outcome was the degree of disability at 90 days as assessed by the modified Rankin scale. Secondary outcomes included major disability or death at 90 days and death at 90 days. Researchers also recorded serious adverse events such as pneumonia.
Patients were placed in the assigned head position at an average of 14 hours after onset of stroke (interquartile range [IQR] = 5-35).
Rate of adherence to the assigned head position for 24 hours was lower in patients assigned the lying-flat position (87%; median time, 23.3 hours; IQR = 20-24) vs. those assigned the sitting-up position (95%; median time, 24 hours; IQR = 23-24; P < .001).
At 90 days, the degree of disability did not differ between the two groups (unadjusted OR for difference in distribution of scores on modified Rankin scale in those assigned the lying-flat position = 1.01; 95% CI, 0.92-1.1). Prevalence of major disability or death was also similar in patients assigned the sitting-up position (39.7%) and lying-flat position (38.9%; OR = 0.94; 95% CI, 0.85-1.05). Death occurred in 7.4% of patients in the sitting-up group vs. 7.3% of patients in the lying-flat group (OR = 0.98; 95% CI, 0.85-1.14). The rate of pneumonia did not differ between the two groups.
“Most of the patients in our trial had the assigned head position implemented after the time window for reperfusion with thrombolytic or endovascular treatment had passed, and the patients had mostly mild neurologic deficits from a range of causes of stroke,” Anderson and colleagues wrote. “It is possible that earlier initiation of head position after the onset of symptoms when the ischemic penumbra is potentially modifiable may have produced different results.” – by Darlene Dobkowski