Use of NIRS during mechanical thrombectomy for ischaemic stroke

Intra-arterial thrombectomy (IAT) is a well-proven method of restoring cerebral perfusion in patients suffering from an ischemic stroke. Anesthetic patient management during the IAT, on the other hand, is not evidence based. The existing guidelines are based on expert opinion and advise only broadly on periprocedural blood pressure management without accounting for any specific patient and procedural factors.

In brain tissue areas, where perfusion is critically low, functioning of the brain autoregulation mechanism is extremely challenged. Any further drops perfusion may lead to hypo-perfusion and irreversible ischemia while sudden increase in perfusion pressure, like after recanalization, can lead to hyper-perfusion and potentially to haemorrhagic conversion. Thus, there is a need for a measure of cerebral perfusion to guide and individualize the blood pressure management. Near infrared spectroscopy (NIRS) might provide the answer.

The NIRS monitor is capable of detecting changes in cerebral oxygenation

NIRS: continous collection of data througout the surgery



NIHHS: pre-procedure, after 24 hrs, at discharge
Modified Rankin scale: after 3 months

Before the IAT, a NIRS sensor will be applied to the skull, bilaterally, directly above the flow region of the middle cerebral artery (MCA).

ADDENDUM (06-07-2019):
On arrival in the angiography suite, the NIRS sensors will be applied to the scalp bilaterally. When eligible patients or their legal representatives are able to provide informed consent, NIRS sensors will be applied over the temporal lobes. If informed consent cannot be acquired before the start of the procedure, for example due to patient aphasia and/or absence of legal representatives, the NIRS sensors will be applied over the frontal lobes. Deferred consent will be sought and attained at a later date before the use of the data from these patients.