Endovascular Treatment of Acute Ischemic Stroke Using the Stent Retriever-Assisted Vacuum-Locked Extraction Technique

Samenvatting

Source: Schregel, K., et al. Optimized Management of Endovascular Treatment for Acute Ischemic Stroke. J. Vis. Exp. (2018).

This video demonstrates the endovascular treatment of acute ischemic stroke using the stent retriever-assisted vacuum-locked extraction technique. A guiding sheath is introduced through the femoral artery to reach the clot. A catheter with a stent retriever secures and extracts the clot. Vascular imaging is done to confirm successful reperfusion.

Protocol

All procedures involving human participants have been performed in compliance with the institutional, national, and international guidelines for human welfare and have been reviewed by the local institutional review board.

1. Patient Management in the Emergency Room (ER) - Target Time: 10 min

NOTE: The following steps have to be performed by the stroke neurologist.

1. Inform the neuroradiologist that a patient with signs suggestive of acute stroke is expected prior to the arrival of patient. State age and symptom onset, if known.
   1. Furthermore, inform the anesthesiologist about the potential upcoming endovascular treatment or EVT (first call).
   2. Have the neuroradiologist inform the interventional neuroradiologist about a suspected upcoming acute stroke patient.
2. Perform a rapid clinical assessment of the patient upon arrival, including the quantification of functional impairment according to the National Institutes of Health Stroke Scale or NIHSS. Thus, test the level of consciousness, vision, motor and sensory function, language and speech, as well as extinction and inattention.
3. Meanwhile, have the ER nurse place two large peripheral venous catheters and take a blood sample for immediate laboratory analysis.
4. Have the ER nurse attach an Electrocardiogram (ECG), blood pressure, and blood oxygen saturation mobile monitoring systems to the patient.
5. If stroke is suspected, escort the patient to the angiography suite (scenario A) or to the Computed Tomography or CT imaging site adjacent to the angiography suite (scenario B), depending on NIHSS score and time from symptom onset to admission.
   1. Take a backpack containing emergency equipment and a complete set for intravenous thrombolysis. Include 90 mg recombinant tissue plasminogen activator (rtPA), syringes, i.v. lines, and a syringe pump in this set.
6. If the clinical condition of the patient is not consistent with stroke, treat the patient according to respective neurological guidelines.

2. Diagnostic Imaging in Scenario A = NIHSS 7 or Above and Less than 6 h Elapsed since Symptom Onset - Target Time to Imaging: 15 min

NOTE: The following steps have to be performed by the neuroradiologist.

1. Have the neurologist escort the patient directly to the angiography suite.
2. Position the patient on the angiographic table together with the neurologist and the neuroradiological technician.
   1. Position the patient’s head within the headholder so that the orbitomeatal line is parallel to the rotation pane. Cover the eyes and fixate the head with two straps to prevent motion.
3. Perform a standard 20s non-enhanced rotational flat panel detector CT (FDCT) and a standard biphasic FDCT angiography (FDCTA).
   1. Perform FDCT on the angiography system using the following parameters: 20s rotation; 200° total angle with ~500 projections; 109 kV; 1.8 µGy/frame; effective dose ~2.5 mSv.
   2. For the FDCT angiography (FDCTA) on the angiography system, perform an intravenous injection of 60 mL contrast agent at an injection rate of 5 mL/s, followed by 60 mL saline chaser at the same injection rate of 5 mL/s.
   3. Use the antecubital vein of the right arm in order to optimize the bolus concentration. Use a power injector for injection.
   4. Use the following specifications of FDCTA: 2 x 10 s rotation; 200° total angle (0.8° per frame); 70 kV; 1.2 µGy/frame; effective dose ~2.5 mSv.
      NOTE: The first rotation is timed after a bolus-watching digital subtraction angiography to capture the peak arterial phase, while the second phase is acquired automatically after 5 s, correlating to the venous phase. Raw data are automatically transferred and automatically reconstructed on a commercially available workstation.
4. Review the acquired images together with the interventional neuroradiologist to rule out an intracranial hemorrhage using the FDCT and to detect large vessel occlusion (LVO) using the early phase of the FDCTA. Use the late venous phase of the FDCTA to evaluate the collateral status.
5. After exclusion of an intracranial hemorrhage and confirmation of the patient's eligibility, have the neurologist start intravenous administration of rtPA (dose: 0.9 mg/kg infused over 60 min with 10% of the total dose as an initial bolus).
   NOTE: Total target time from admission to initiation of rtPA treatment: 20 min.
6. Call the anesthesiologist (second call) and confirm an upcoming EVT.
7. Have mobile monitoring devices replaced by stationary devices present in the angiography suite and start preparations for EVT immediately (see step 4, "Preparation of EVT").
8. If FDCT and FDCTA are not consistent with acute ischemic stroke, symptoms are sustained, and the patient is eligible for an Magnetic Resonance Imaging (MRI) scan, have the neurologist escort the patient to the MRI suite. Perform an MRI to further investigate the neurological condition of the patient.

3. Diagnostic Imaging in Scenario B = NIHSS below 7 and/or More than 6 h Elapsed since Symptom Onset - Target Time: 25 min

NOTE: The following steps have to be performed by the neuroradiologist.

1. Have the neurologist escort the patient to the CT suite.
2. Have the neuroradiological technician perform a non-enhanced CT scan immediately after the arrival of the patient at the imaging site.
   NOTE: One can decide to perform an MRI instead of a CT only if a CT is not possible or if other factors favor an MRI scan.
3. Read the CT images quickly in order to rule out an intracranial hemorrhage and a large demarcated infarct.
4. After excluding both, confirm the patient's eligibility. If less than 4.5 h have elapsed since symptom onset, have the neurologist start intravenous administration of rtPA (dose: 0.9 mg/kg infused over 60 min with 10% of the total dose as an initial bolus).
   1. Give the initial bolus on-site while the patient is lying on the CT table.
      NOTE: Total target time from admission to initiation of rtPA treatment: 20 min.
5. Have the neuroradiological technician perform CT angiography (CTA) and perfusion (CTP) scans.
6. After completion of CTA and CTP, evaluate whether the patient is eligible for EVT.
   NOTE: Eligibility criteria are: presence of LVO on CTA detected by lacking opacification and absence of a large demarcated infarct determined using the Alberta Stroke Program Early CT score (ASPECTS) 12 on non-enhanced CT. ASPECTS values of 4 and below indicate large infarct demarcation.
   1. Use CTP to determine the amount of still salvageable tissue. For this determination, assess ASPECTS on maps of cerebral blood volume (CBV); patients are eligible for EVT with a CBV-ASPECTS of above 4.
7. If the patient is eligible for EVT, call the anesthesiologist and confirm the upcoming EVT.
   1. Have the neurologist transfer the patient immediately to the adjacent angiography suite, where the patient is positioned on the angiographic table and mobile monitoring devices are replaced by stationary devices present in the angiography suite.

4. Preparation of EVT - Target time: 10 min

NOTE: The following steps have to be performed by the neuroradiologist.

1. Prepare the patient for the EVT together with the neuroradiological technician.
   1. Have the neuroradiological technician set up the material required for EVT, i.e., catheters, flushing infusions, syringes, etc.
   2. Shave and disinfect the patient's groin with skin antiseptic (e.g., Kodan tincture forte) and place sterile drapes to ensure aseptic conditions for EVT.
2. Have the anesthesiologist commence conscious sedation: induce with ketamine (1 mg/kg) in combination with propofol (1 mg/kg) intravenously and maintain a continuous infusion of propofol (1-2 mg/kg/h) to ensure sufficient spontaneous breathing and patient cooperation.
   NOTE: Conscious sedation is the preferred method during EVT.
   1. If conscious sedation seems inappropriate due to sustained agitation or movement of the patient, have the anesthesiologist intubate the patient so that EVT is performed under general anesthesia.
      1. Induce with a sufentanil bolus (0.2 - 0.4 µg/kg) and a propofol bolus (1.5 -2 mg/kg) intravenously. Improve intubation conditions with muscle relaxation using a rocuronium bolus (0.6 mg/kg). Maintain general anesthesia with sevoflurane (0.5-1.5 MAC) and additional repetitive boli of sufentanil (0.2-0.5 µg/kg), if necessary. To facilitate intubation, sway the angiographic table towards the ventilation machine.

5. Performance of EVT

NOTE: The following steps have to be performed by the interventional neuroradiologist.

1. Puncture the right femoral artery in the groin using an 18-G puncture needle and introduce a peripheral 8F guiding sheath. Then start EVT; total target time from patient admission to groin puncture is 30 min in scenario A and 45 min in scenario B.
2. Perform EVT.
   1. Choose the Stent retriever Assisted Vacuum-locked Extraction (SAVE) technique as the primary treatment approach. If needed, adapt the procedure to individual requirements of the situation. In cases of tandem occlusions, use the ReWiSed CARe technique for simultaneous thrombectomy of the intracranial lesion and treatment of the cervical stenosis.
3. Have the anesthesiologist closely monitor the vital signs of the patient during the whole procedure. In particular, have the anesthesiologist take immediate action to prevent hypotension.
4. After a control angiogram confirms successful reperfusion, defined as a modified Thrombolysis in Cerebral Infarction (mTICI) score of 2b – 3, perform a flat-panel detector angiographic CT. Read the images to rule out complications of the treatment, e.g., intracranial hemorrhage.
5. Remove all materials and dress the wound in the groin. Use a vascular closure device to close and seal the puncture in the femoral artery.

Materialen

Lijst van materialen gebruikt in dit artikel

Naam	Bedrijf	Catalogusnummer	Opmerkingen
Actilyse (recombinant tissue plasminogen activator)	Boehringer Ingelheim, Ingelheim am Rhein, Germany	n/a	generic products from other pharmaceutical companies can be used
Imeron 400 (contrast agent)	Bracco Imaging GmbH, Konstanz, Germany	n/a	generic products from other companies can be used
Siemens ArtisQ angiography system	Siemens Healthcare, Forchheim, Germany	n/a	an angiography system of another manufacturer can be used; specifications of FDCT and FDCTA described in protocol are valid for ArtisQ
Siemens syngo X worklplace	Siemens Healthcare, Forchheim, Germany	n/a	a workstation from another manufacturer can be used
Ketamine (e.g. Ketanest)	Pfizer Pharma PFE GmbH, Berlin, Germany	n/a	generic products from other pharmaceutical companies can be used
Propofol (e.g. Propofol-Lipuro)	B. Braun Melsungen AG, Melsungen, Germany	n/a	generic products from other pharmaceutical companies can be used
Sufentanil (e.g. Sufenta)	Janssen-Cilag GmbH, Neuss, Germany	n/a	generic products from other pharmaceutical companies can be used
Rocuroniumbromid	B. Braun Melsungen AG, Melsungen, Germany	n/a	generic products from other pharmaceutical companies can be used
Sevoflurane (e.g. Sevofluran)	Baxter Deutschland GmbH Medication Delivery, Unterschleissheim, Germany	n/a	generic products from other pharmaceutical companies can be used
Vascular closure device (e.g. Angio-Seal)	Terumo Interventional Systems, Eschborn, Germany	n/a	generic products from other companies can be used
Peripheral 8F guiding sheath	Terumo Interventional Systems, Eschborn, Germany	n/a	generic products from other companies can be used
Skin antiseptic (e.g. kodan tincture forte, coloured)	Schuelke & Mayr GmbH, Norderstedt, Germany	n/a	generic products from other companies can be used
18 G intradyn puncture needle	B. Braun Melsungen AG, Melsungen, Germany	n/a	generic products from other companies can be used