Non-invasive convective head cooling during stroke thrombectomy: A prospective multi-center feasibility trial

Non-invasive convective head cooling is a promising putative neuroprotective therapy for ischemic stroke patients as it may portably, non-invasively, and selectively cool the ischemic penumbra. We aimed to investigate the feasibility of utilizing non-invasive convective head cooling in ischemic stroke patients before and during endovascular thrombectomy (EVT).

We conducted a multi-center, prospective, non-randomized, open-label trial at two comprehensive stroke centers in ischemic stroke patients where EVT was planned. Patients were assessed for eligibility in the emergency department (ED) and had a cooling cap fitted that circulated coolant between -5°C and 0°C until EVT completion. The primary feasibility endpoint was adherence, defined as tolerating cooling for ⩾50% of the time from cooling cap application until EVT completion.

Between July and November 2024, 40 EVT patients (19 (47.5%) female, mean ± SD age 71.6 ± 12.6 years) underwent a median (IQR) duration of convective head cooling of 86 (58-106) min. Thirty-nine (97.5%) participants met the primary feasibility endpoint. The enrollment rate was five participants per site per month. Median (IQR) time from comprehensive stroke center arrival to cooling start was 10 (5-51) min. Thirty-two (80%) patients received general anesthesia. eTICI 2b-3 reperfusion was achieved in 38 (95.0%) participants. Median (IQR) 24-h infarct volume was 14.3 (5.5-29.1) mL. Median (IQR) 3-month modified Rankin Scale score was 2 (1-5). Three-month mortality occurred in 8/38 (21.1%) participants. Nine serious adverse events occurred in 8 (20.0%) participants, none of which were attributed to head cooling.

Convective head cooling is feasible in patients undergoing EVT and warrants further investigation in larger randomized controlled trials.