Abstract Body: Background:
It remains uncertain whether remote ischemic conditioning (RIC) with transient cycles of limb ischemia and reperfusion is an effective supplement to standard-of-care management of intracerebral hemorrhage (ICH)
Objective:
To evaluate whether RIC can reduce hematoma expansion and peri-hematoma edema in patients with ICH.
Design, Setting and participants:
This is a predefined substudy to a randomized clinical trial conducted at four stroke centers in Denmark. Among the subset of participants with ICH, brain imaging was performed at admission, after 24 hours and at 7 days. Hematoma expansion over time was assessed on non-contrast CT or MRI using susceptibility weighted sequences.
Intervention:
RIC was induced by using an inflatable cuff on the upper extremity with a cuff pressure of at least 200 mm Hg and sham cuff pressure of 20 mm Hg. Each treatment application consisted of 5 cycles with 5 minutes of inflation followed by 5 minutes of deflation.

Main Outcomes and Measures:
The primary end point was the risk of hematoma expansion defined as absolute growth exceeding 6 mL or a relative growth of more than 33% from the initial scan. Difference in 7 days hematoma reabsorption rate was a secondary outcome and was defined as the difference in hematoma volume between the baseline and day 7.
Findings: Among 1500 patients who were prehospitally randomized, 165 patients had an ICH. Of them, 87 patients were randomly assigned to RIC and 78 to sham treatment. The median age was 71 (60, 77), 73 (44%) were females, and the median onset to randomization was 40 minutes (30, 69). The median National Institute of Health Stroke Scale score was 12, and 19 patients (12%) had either hematoma evacuation or placed an external ventricular drain. There was no difference on the risk of 24-hour hematoma expansion in RIC treated, -0.052 (-0.20-0.10), p=0.504 (ref: Sham, unadjusted) nor the 7-day hematoma reabsorption rate (day 7 - baseline) in the RIC treated patients 5.47mL (-4.570mL-15.52mL), p=0.280. Supplementary analysis will be presented at the conference.

Conclusions and Relevance:
RIC initiated in the prehospital setting and continued in the hospital did not reduce hematoma expansion or peri-hematoma edema in patients with ICH.

Trial registration: ClinicalTrials.gov:NCT03481777.