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

## TL;DR

This study shows that non-invasive head cooling is feasible for stroke patients during a procedure called thrombectomy, with most participants tolerating the treatment well.

## Contribution

The study demonstrates the feasibility of non-invasive convective head cooling during stroke thrombectomy in a multi-center trial.

## Key findings

- 97.5% of participants met the primary feasibility endpoint of tolerating cooling for at least 50% of the time.
- The median time from stroke center arrival to cooling start was 10 minutes, indicating rapid implementation.
- No serious adverse events were attributed to the head cooling treatment.

## Abstract

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.

Graphical abstract