Recently, the brachial plexus block has been actively performed for shoulder surgery. Brachial plexus anesthesia is used alone or in combination with general anesthesia. In particular, many cases have been practiced only by brachial plexus anesthesia for shoulder surgery using arthroscopy.
 Patients complain of pain during surgery under arthroscopy after brachial plexus anesthesia. Around the shoulder joint, the scapula nerve, the axillary nerve and the lateral pectoral nerve are dominant. The inner brachial region and the lower part of the scapula spine do not produce complete sensory blockage by only brachial plexus anesthesia. In previous Cadaver study, the path and distribution of scapula nerve, axillary nerve and the lateral pectoral nerve were checked and the area where each nerve dominates and the areas where several nerves were overlapping was turned out. The literature confirming the extent of sensory blockage around the joint with shoulder arthroscopy hasn’t been found yet. A conventional method of interscalene brachial plexus block for shoulder surgery is to inject drugs in contact with or near a nerve, or into a sheath that surrounds a nerve bundle. Among these two methods, when the drug is injected into the sheath(fascia), the drug spreads well around the nerve. Therefore, when comparing the near-nerve injection method with the intrafascial injection method, the study was planned to confirm whether the anesthesia was achieved by the intrafascial injection method can achieve a faster anesthesia time and a wider range of anesthesia was obtained.

Prevention

All subjects will be fasted for at least 8 hours in the same manner as patients receiving general anesthesia here, regardless of participation in this study. Oxymetry, electrocardiogram, and non-invasive blood pressure measurement should be performed in the lying position immediately after arriving operating room. Turn his or her head to the opposite side of the procedure, put a pore or pedestal under his or her back to make a posture, and prepare for disinfection and treatment.
With view of ultrasound, C5, C6, and C7 nerve roots, or the superior, middle, and inferior trunks, which form the brachial plexus between the ribs at about 2cm above the clavicle, are identified. A 25G 5cm nerve-stimulating needle is aimed at the C5 root or superior trunk (in-plane technique) to check muscle twitching at 1.5mA, if the muscle twitching is made, stop the needle entry , and check the tremor at 0.5mA and 0.2mA to prevent intraneural injection. Make sure there is no twitching and inject 0.5% ropivacaine 25cc. If there is twitching at 0.2 mA, the needle is retracted by 1 mm until the tremor disappears and the drug is injected (group C). In the case of group I, place a needle tip in the fascia of the scalene muscle between the upper and middle trunk of the brachial plexus, and inject 0.5% ropivacaine 25cc after confirming that there is no tremor at 0.2mA. In addition, supraclavicular nerve block was administered with 0.5% ropivacaine 3cc in both groups.
Anesthesiologists who perform anesthesia know the near-nerve injection group (Group C) and the intrafascial injection group (Group I) at the time of the procedure. The evaluation of sensory block is made by an orthopedic surgeon who performs shoulder surgery, and the surgeon does not know which group the patient belongs to.

Arm Label

Target Number of Participant

Arm Type

Arm Description

In the case of intrafascial injection group, the fascia of the scalene muscle surrounding the brachial plexus is confirmed by ultrasound, and the nerve-block needle penetrates the fascia and confirms that the needle is located in the fascia, and then 0.5% ropivacaine is administered.

Arm Label

Target Number of Participant

Arm Type

Arm Description

In the case of injection near the nerve, the brachial plexus between the scalene muscle is confirmed by ultrasound and nerve stimulation, and the needle is placed near the nerve and administered 0.5% ropivacaine without penetrating the fascia of the scalene muscle.

Gender

Age

Description

1) Patient with rotator cuff disorder undergoing arthroscopic surgery under brachial plexus anesthesia
2) American Society of Anesthesiologist Patient Status I~III

1)Pregnancy
2) Emergency operation 
3) obesity (Body mass index >35kg/m2)  
4) anticoagulant therapy 
5) Infection of the nerve block site
6) Unilateral diaphragmatic paralysis opposite the surgical site  
7) psychiatric disease or cognitive disorder

Time to get successful anesthesia for shoulder surgery

During 30 minutes after the ends of brachial plexus block procedure

Checking the range of sensory blockage in the shoulder joint area that can be identified through arthroscopy

For 1 hour after start of surgery