Delayed combination therapy of local brain hypothermia and decompressive craniectomy on acute stroke outcome in rat

Hypothermia and decompressive craniectomy (DC) have been shown to be neuroprotective. This study was designed to evaluate neuroprotective effects of delayed singular or combination of DC and local hypothermia on stroke.

Cerebral ischemia was induced in 48 Wistar rats assigned to 4 groups: control, decompressive craniectomy (DC), local hypothermia (LH), combination of hypothermia and craniectomy (HC). Infarct size and BBB disruption were measured 48 hr after ischemia insult. Neurological deficits were assessed at 24 and 48 hr after stroke by using sticky tape test, hanging-wire test and Bederson's scoring system. BBB disruption was measured by Evans blue dye leakage.

Although infarct size was significantly reduced in LH, DC and HC groups (P<0.001), combination therapy was more neuroprotective compared to craniectomy alone (P<0.01). BBB disruption was significantly reduced in DC (P< 0.05) and LH and HC (P< 0.01).While sticky tape test (P<0.05 at 24 hr; P<0.001 at 48 hr) and hanging-wire test (P<0.05) showed better behavioral performance only in HC, Bederson test showed improved behavioral functions of both LH (P<0.05 at 24 hr and P<0.01 at 48 hr) and HC animals (P<0.01). Neurological deficits were also decreased in LH (P<0.05) or HC (P<0.05 at 24 hr; P<0.01 at 48 hr) groups compared to the DC group at the same time.

Based on our data, although both delayed local hypothermia and craniectomy are protective after stoke, combination therapy of them is more neuroprotective than given alone.