Blood pressure management after mechanical thrombectomy in stroke patients

Transauricular nerve stimulation in acute ischaemic stroke requiring mechanical thrombectomy: Protocol for a phase 2A, proof-of-concept, sham-controlled randomised trial

BACKGROUND

Labile blood pressure after acute ischaemic stroke requiring mechanical thrombectomy is independently associated with poor patient outcomes.

OBJECTIVES

This study protocol describes is designed to determine whether transauricular nerve stimulation, improves baroreflex sensitivity, reduces blood pressure variability in the first 24 hours after acute ischaemic stroke requiring mechanical thrombectomy.

DESIGN: PHASE 2A, PROOF-OF-CONCEPT, SHAM-CONTROLLED RANDOMISED TRIAL

Methods and Analysis: 36 individuals undergoing mechanical thrombectomy for acute ischaemic stroke with established hypertension aged >18 years will be randomly allocated to receive bilateral active or sham transauricular nerve stimulation for the duration of the mechanical thrombectomy procedure (AffeX-CT/001 investigational device). The intervention will be repeated for 1h the morning following the mechanical thrombectomy. Non-invasive blood pressure will be measured ≥2h for 24h after mechanical thrombectomy. Holter electrocardiographic monitoring will be recorded during transauricular nerve stimulation. Participants, clinicians and investigators will be masked to treatment allocations. The primary outcome will be the coefficient of variation of systolic blood pressure. Secondary outcomes include additional estimates of blood pressure variability and time/frequency-domain measures of autonomic cardiac modulation An adjusted sample size of 36 patients is required to have a 90% chance of detecting, as significant at the 5% level, a difference in the coefficient of variation in systolic blood pressure of 5±4mmHg between sham and active stimulation [assuming 5% non-compliance rate in each group]. Ethics: confirmed on 16 March 2023 by HRA and Health and Care Research Wales ethics committee (reference 23/WA/0013).

DISCUSSION

This study will provide proof-of-concept data that examines whether non-invasive autonomic neuromodulation can be used to favourably modify blood pressure and autonomic control after acute ischaemic stroke requiring mechanical thrombectomy.

TRIAL REGISTRATION

Trial registration number: NCT05417009.

Efficacy of Early Intensive Blood Pressure Management After Thrombectomy: Protocol for a Randomized Controlled Clinical Trial (IDENTIFY)

BACKGROUND

The optimal strategy for blood pressure management after thrombectomy remains unknown. The primary objective of The Early Intensive Blood Pressure Management after Endovascular Thrombectomy (IDENTIFY) study is to explore the efficacy and safety of early intensive blood pressure management strategies after thrombectomy compared with that of standard management.

METHODS

The IDENTIFY study is a prospective, randomized, open-label, assessor-blinded multicenter clinical trial. Patients with acute anterior circulation ischaemic stroke who underwent endovascular thrombectomy within 6 h of stroke onset, achieved successful recanalization, and had two consecutive blood pressure readings > 130 mm Hg during the first 6 h after thrombectomy will be enrolled and centrally randomized into intensive or standard management groups in a 1:1 ratio. Continuous blood pressure monitoring will be initiated at the end of thrombectomy, and patients with high blood pressure during the transfer to the wards will also be enrolled. For patients in the intensive management group, the target blood pressure will be < 130 mm Hg, and the use of antihypertensive drugs will be discontinued if systolic blood pressure goes below 110 mm Hg. The target blood pressure for the standard management group will be < 180 mm Hg, and if systolic blood pressure decreases below 140 mm Hg, the use of antihypertensive drugs will be stepwise decreased until the systolic blood pressure reaches 140 mm Hg again or the infusion is discontinued. Patients will have their blood pressure reduced to the target range within 1 h from randomization and maintained until 24 h after thrombectomy with intravenous hypertensive drugs. A sample size of 600 was predicted. The primary outcome will be the rate of dependency (modified Rankin Scale scores 3-6) at 90 days. Secondary outcomes will include intracerebral hemorrhage (either symptomatic or asymptomatic) within 24 h and 7 days, malignant brain oedema, all-cause death, death and severe disability at 90 days, and quality of life at 90 days, which will be measured using the EuroQol-5 Dimensions-5 Level (EQ-5D-5L) and the 36-Item Short Form Health Survey (SF-36). Safety outcomes will include stroke recurrence within 24 h, early neurological deterioration, hypotension within 24 h, death within 7 days after endovascular thrombectomy, and all-cause acute kidney injury. Trial registration chictr.org.cn (identifier: ChiCTR2200057770). Registered March 17, 2022, http://www.chictr.org.cn/edit.aspx?pid=162575&htm=4.

Periprocedure Management of Blood Pressure After Acute Ischemic Stroke

The management of acute ischemic stroke primarily revolves around the timely restoration of blood flow (recanalization/reperfusion) in the occluded vessel and maintenance of cerebral perfusion through collaterals before reperfusion. Mechanical thrombectomy is the most effective treatment for acute ischemic stroke due to large vessel occlusions in appropriately selected patients. Judicious management of blood pressure before, during, and after mechanical thrombectomy is critical to ensure good outcomes by preventing progression of cerebral ischemia as well hemorrhagic conversion, in addition to optimizing systemic perfusion. While direct evidence to support specific hemodynamic targets around mechanical thrombectomy is limited, there is increasing interest in this area. Newer approaches to blood pressure management utilizing individualized cerebral autoregulation-based targets are being explored. Early efforts at utilizing machine learning to predict blood pressure treatment thresholds and therapies also seem promising; this focused review aims to provide an update on recent evidence around periprocedural blood pressure management after acute ischemic stroke, highlighting its implications for clinical practice while identifying gaps in current literature.

Nursing Care of the Acute Ischemic Stroke Endovascular Thrombectomy Patient

Nurses are an integral part of the multidisciplinary team caring for a patient eligible for endovascular thrombectomy. Their care includes obtaining health history, performing clinical assessments, using critical thinking to anticipate the care path, and communicating findings to other team members. The prehospital and emergency department nurses utilize stroke severity scales to identify a possible thrombectomy candidate and help expedite intervention. In the interventional laboratory, nursing collaborates with radiology technologists and interventionalists to ensure patient safety and monitor for intraprocedural complications. Post-procedure, the intensive care nurse delivers complex care to ensure optimal neurological outcome and assess for postprocedural complications. Nursing is essential in every phase of care along with collaboration with other disciplines.

Stroke thrombectomy perioperative anesthetic and hemodynamic management

There is an ongoing debate about the optimal anesthetic and hemodynamic management of acute stoke patients with large vessel occlusion undergoing endovascular mechanical thrombectomy. Several prospective and retrospective analyses, and randomized controlled trials, attempted to address the challenges of using different anesthetic modalities in acute stroke patients requiring mechanical thrombectomy. We review the advantages and disadvantages of monitored anesthesia care, local anesthesia, conscious sedation, and general anesthesia, along with the relevance of hemodynamic management and perioperative oxygenation status in these complex patients.

Transcranial Doppler 6 h after Successful Reperfusion as a Predictor of Infarct Volume

OBJECTIVES

The aim of the study is to analyze the hemodynamic changes in the middle cerebral artery (MCA) after endovascular revascularization in acute ischemic stroke (AIS) due to large vessel occlusion and its association with the infarct volume size in the control head CT.

MATERIALS AND METHODS

Prospective study of patients with AIS due to internal carotid artery terminus or M1 segment of the MCA occlusion, who underwent endovascular treatment with a final TICI 2b-3 score, without concomitant stenosis ≥50% in both cervical carotid arteries. Transcranial Doppler ultrasound (TCD) of both MCAs was carried out at 6 h after the endovascular procedure. Mean flow velocities (MFV) after arterial reperfusion and its association with the infarct volume size in 24-36 h control head CT were determined.

RESULTS

91 patients (51 women) were included with a median age of 78 years and National institute of Health Stroke Scale of 18. The MCA was occluded in 76.92%, and intravenous thrombolysis was administered in 40.7%. The incidence of symptomatic intracranial hemorrhage was 5.5%. At three months, mortality was 19.8% and a 52.7% of patients achieved functional independence (modified Rankin Scale 0-2). After a multivariable logistic regression analysis, an increase in the MFV greater than 50% at 6 h in the treated MCA compared to contralateral MCA, was an independent predictor of large infarct volume in the control head CT with an OR 9.615 (95%CI: 1.908-47.620), p=0.006 CONCLUSIONS: Increased MFV assessed by TCD examination following endovascular recanalization is independently associated with larger infarct volume.