Stellate Ganglion Block and Cerebral Vasospasm

Study Overview
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Brief Summary
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At present, cerebral vasospasm (cVS) is the main cause of delayed cerebral infarction (DCI), which leads to high disability and mortality rate after aneurysmal subarachnoid hemorrhage. As a consequence, the key of reducing DCI is to prevent cVS. But unfortunately, despite years of efforts, the prevention and treatment of cVS is still a major clinical dilemma and various ways of treatment are still being explored. Recent studies have shown that stellate ganglion block (SGB) can dilate cerebral vessels and alleviate the impact of existing cVS. However, there is no study to evaluate the effect of early application of SGB on the improvement and prevention of cVS after aSAH.

Detailed Description
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Cerebral vasospasm refers to the extensive segmental or diffuse contraction of cerebral vasculature after aSAH, and cerebral blood flow is significantly reduced, which can lead to delayed cerebral ischemia (DCI) or delayed ischemic neurological dysfunction (DIND). Past studies have shown that if cerebral vasospasm occurs in patients with aSAH, the proportion of ischemic brain injury can be as high as 20%-30%.Obviously, prevention and treatment of CVS are the key to reducing the disability and mortality of aSAH.

Official Title
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Effect of Early Stellate Ganglion Block for Cerebral Vasospasm After Aneurysmal Subarachnoid Hemorrhage: a Randomized Controlled Trial (BLOCK-CVS)

Conditions
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Aneurysmal Subarachnoid Hemorrhage, Stellate Ganglion Block, Cerebral Vasospasm

Intervention / Treatment
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* Procedure: Stellate ganglion block


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age range: 18-65 years old; Within 48 hours after onset of aSAH,and planning surgical treatment(aneurysm clipping); Preoperative Hunt-Hess grade 2-3 Sign informed consent. Exclusion Criteria: ASA > grade III; Patients with posterior circulation aneurysm, ophthalmic aneurysms or internal carotid aneurysms; patients with multiple aneurysms; Patients with severe coagulation dysfunction; Patients with trauma and local infection in the nerve block area; Local anatomic structure changes (neck structure changes caused by radiotherapy, chemotherapy and surgery); MCA stenosis or infarction was found by preoperative imaging; Patients with poor temporal window signal revealed by preoperative TCD (clear waveform image could not be obtained); Allergy to known local anesthetics; Pregnant and lactating women.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Intervention group<br>In addition to routine anesthesia management and surgical operations, a stellate ganglion block was performed before induction of anesthesia, and then receive standard care after operation. Related statistical indicators were collected prospectively. | Procedure: Stellate ganglion block<br>* After the patient entered the operating room, early SGB will be performed by a designated experienced anesthesiologist using the B-ultrasound visualization technique. The intervention site is the ipsilateral side of the planned craniotomy site. After routine disinfection, 0.5% ropivacaine 8-10 mL will be injected into the surface of the longus colli muscle on the medial side of the prevertebral fascia at the level of the C6 anterior tubercle, and then the puncture point will be covered with sterile dressings. The success criteria of e-SGB are Horner's syndrome, which is characterized by a miosis, ptosis, enophthalmos, conjunctival hyperemia and facial reddishness without sweating. For the camouflaging arm, the anesthesiologist only covered the corresponding part of the patient with sterile dressings to confuse the follow-up, without any puncture. All patients will be admitted to the ICU after the operation and then receive the standard of care.<br>|
| No Intervention: Blank control group<br>In this study, a blank control was used. Routine anesthesia management and surgical operation were used without any special interventions(only an camouflaging action), and then receive standard care after operation. Only relevant statistical indicators were collected prospectively. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The incidence of symptomatic vasospasm within 14 days after aSAH | Symptomatic vasospasm is defined as new focal or global neurological dysfunction or a decrease in the Glasgow coma score by more than 2 points, and with angiographic vasospasm on TCD or CTA. | within 14 days after aSAH | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The incidence of TCD vasospasm withing 14 days after aSAH. | The mean blood flow velocity (MFV) of the middle cerebral artery ≥ 120 cm/s or Lindegaard index (ratio of MFV of the middle cerebral artery to the internal carotid artery) ≥ 3. | within 14 days after aSAH | 
| The incidence of CTA vasospasm on the days 3-5 after operation | Compared with the preoperative baseline, the corresponding vessel diameter narrowed by more than 30% or new segmental stenosis occurred, not related to atherosclerosis or mechanical artery stenosis caused by arterial clamps or coils. | on the days 3-5 after operation | 
| The incidence of hypoperfusion in CTP diagnosis on the days 3-5 after operation | The incidence of hypoperfusion in CTP diagnosis | on the days 3-5 after operation | 
| The incidence of new cerebral infarction observed on the days 90 after operation and discharge . | New cerebral infarction is defined only as the appearance of new low-density infarct shadow on CT image compared with preoperation. | on the days 90 after operation and discharge | 
| The changes of he mean blood flow velocity (mBFV) after operation | the changes in the mean blood flow velocity (mBFV) of all large intracranial anterior circulation vessels | on the day before surgery (T0) and on the immediate (T1),1st (T2), 2nd (T3), 3rd (T4), 5th (T5) ,7th(T6) days after operation. | 
| Total length of stay in the intensive care unit and hospital. | Days | on the 90 days | 
| The modified Rankin scale at discharge, 30days, and 90 days | The modified Rankin scale ≤2 is defined as good prognosis | on the 30 and 90 days | 
| All-cause mortality rate up to 90 days. | The rate | on the 90 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Cerebral vasospasm, Stellate ganglion block