The already well-established therapy, Therapeutic hypothermia, has now shown signs of being a possible treatment option for ischaemic stroke.
Therapeutic hypothermia has already demonstrated clear neuroprotective effect.
It has been widely used in the aid of neonatal hypoxic encephalopathy and cardiac arrest.
Researchers have been trying to apply therapeutic hypothermia to the treatment of acute ischaemic stroke for decades. However, many hypothermia induction methods that proved effective in rodent transient cerebral ischaemia models have encountered challenges in clinical translation.
The reason may lie in the differences between rodents and humans in brain volume and metabolism, this is as well as the mismatch between hypothermia induction methods performed in clinical and preclinical trials. Therefore, how to induce hypothermia safely and efficiently in an appropriate model is the key to the clinical translation of therapeutic hypothermia.
In this study, an animal model of transient ischaemia-reperfusion was established to simulate the pathogenesis and treatment of ischaemic stroke by placing/withdrawing endovascular coils.
Arterial blood was extracted from the left femoral artery of the animal models, passed through a heat-exchange unit developed by the team, and then transfused directly into the recanalised cerebral artery via a microcatheter placed previously in the right femoral artery.
This method showed that it could reduce brain temperature rapidly (down to 34°C within 5 min) while maintaining relatively higher core body temperature during a two hour procedure. The study authors believe this treatment could be a viable option as no adverse effects of systemic hypothermia such as shivering and infection were observed, indicating the safety of this method.
To evaluate the neuroprotective effect of cold autologous blood, researchers used MRI scans to evaluate the infarct volume of the animals. Targeted cold autologous blood transfusion effectively reduced infarct volume and infarct core expansion in the acute phase of ischaemic stroke as shown on T2 sequence and diffusion weighted imaging (DWI).
z`Additionally, white matter integrity was preserved by hypothermia as evaluated with diffusion tensor imaging (DTI). Consist with reduced infarct volume, cold autologous blood also improved neurological function.
