Superficial Cervical Plexus Block for Postoperative Analgesia

Study Overview
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Brief Summary
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The incidence of postoperative pain after craniotomy is high. Severe postoperative pain can lead to a series of complications that are detrimental to the recovery of craniotomy patients. Compound local scalp nerve block is a good choice for analgesia after craniotomy. However, the scalp nerve block commonly cannot cover the area of suboccipital retrosigmoid approach craniotomy, leading to incomplete block. Superficial cervical plexus block (SCPB) is theoretically promising to solve the analgesia requirements of such surgical approach. At the same time, ultrasound guidance can not only accurately locate, ensure the effect of block and avoid accidental injury during puncture. The purpose of this study is to explore whether ultrasound-guided superficial cervical plexus block can safely and effectively reduce the requirement of analgesic drugs and pain after craniotomy via suboccipital retrosigmoid approach.

Official Title
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Ultrasound Guided Superficial Cervical Plexus Block for Analgesia After Craniotomy Via Suboccipital Retrosigmoid Approach: A Randomized Controlled Trial

Conditions
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Plexus Block;Analgesia;Neurosurgery

Intervention / Treatment
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* Procedure: Superficial cervical plexus block
* Other: Control group


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Elective suboccipital retrosigmoid approach approach craniotomy; Age between 18 and 65 years; American Society of Anesthesiologists (ASA) physical status I-III. Exclusion Criteria: The patients or legal clients refuse to provide informed consent; Local infection; Preoperative impairment of consciousness and cognitive function; Uncontrolled hypertension; Inability to communicate; Allergies to experimental drugs; History of drug abuse; History of chronic headache; Aphasia and hearing impairment; Patients undergoing second craniotomy; Body mass index < 18.5 kg/m2 or > 35.0 kg/m2;

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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Superficial cervical plexus block group<br> | Procedure: Superficial cervical plexus block<br>* superficial cervical plexus nerve block will be performed under the guidance of ultrasound<br>|
| Sham Comparator: Control group<br> | Other: Control group<br>* ultrasound guidance will be used to determine the location of superficial cervical plexus nerve. The puncture will also be performed by ultrasound guidance, covered with opaque infusion dressing but performed with infusion of 10 ml normal saline.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the cumulative consumption of sufentanil by the PCA | the cumulative consumption of sufentanil by the PCA 24 hours after surgery | 24 hours after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Use of analgesics by the PCA after operation | the cumulative consumption of sufentanil by PCA | at 1, 2, 4, 48 hours after surgery. | 
| Pain severity score | It will be accessed using NRS | at 1, 2, 4, 24, 48 hours after surgery | 
| Anesthesia recovery quality score： | It will be accessed at postoperative 1 and 2 hours using the Anesthesia Steward Emergence Scale. The Anesthesia Steward Emergence Scale(0-6) is divided into three parts: the degree of wakefulness - 2 points for complete recovery, 1 point for response to stimulation, 0 point for no response to stimulation; the degree of airway patency - 2 points for cough according to the doctor's order, 1 point for maintenance of airway patency without support, 0 point for support required for respiratory tract; 2 points for conscious activities of limbs with limb mobility, 1 point for unconscious activities of limbs, point for no activities of limbs. | at 1 hour after surgery | 
| Patient analgesic satisfaction | Patient satisfaction with overall pain management will be evaluated at 24 hours after surgery using NRS | at 24 hours after surgery |