Interscalene Block Versus Infraclavicular Block Plus Suprascapular Nerve Block
Condition: Shoulder Injury
MeSH terms: Shoulder Injuries
Study type: Interventional

Summary: 
      Despite their reliability and efficacy for shoulder surgery analgesia, above clavicle
      brachial plexus blocks are related with phrenic nerve palsy and diaphragm paralysis that may
      not be tolerated in patients with chronic pulmonary disease.

      This RCT will compare the classic Interscalene block with combined infraclavicular block plus
      suprascapular nerve block in patients going for arthroscopic shoulder surgery.

      Main outcome is static pain in the recovery room measured with NRS. Secondary outcomes are
      pain at 12 and 24 hrs and incidence of diaphragmatic paralysis.
    

Detailed description: 
      PATIENT RECRUITMENT

      With the approval of the Ethics Committee of Hospital Clinico Universidad de Chile, 40
      patients undergoing arthroscopic shoulder surgery will be recruited. Enrollment will be
      carried out by an investigator not involved in patient care. Patients' confidentiality will
      be protected.

      STUDY PROTOCOL: GENERAL

      All blocks will be performed by one of the coauthors and conducted preoperatively in an
      induction room. Sedation (2 mg midazolam and 50 μg fentanyl) will be provided for patient
      comfort.

      STUDY PROTOCOL: PERFORMANCE OF THE BLOCK

      Both study groups will receive an ultrasound-guided superficial cervical plexus block.

      In the ICB-SSB group, suprascapular nerve blocks will be carried out using a previously
      described technique. For infraclavicular brachial plexus blocks, 20 mL of levobupivacaine
      0.25% with epinephrine 5 µg/mL will be injected dorsal to the axillary artery, medial to the
      coracoid process.

      In the ISB group, block will carried out using a previously described technique: 20 mL of
      levobupivacaine 0.25% with epinephrine 5 µg/mL will be deposited under the prevertebral
      fascial between the C5 and C6 roots.

      STUDY PROTOCOL: GENERAL ANESTHESIA

      All patients will undergo standardized general anesthesia

      STUDY PROTOCOL: POSTOPERATIVE ANALGESIA

      In the Recovery Room, all patients will receive acetaminophen (usual dose…) and ketoprofen
      (usual dose…) as well as patient controlled analgesia (morphine bolus = 1 mg; lockout
      interval = 8 minutes). On the surgical ward, all subjects will continue to receive
      acetaminophen (usual dise…), celecoxib (usual dose…) as well and patient controlled analgesia
      (morphine bolus = 1 mg IV; lockout interval = 8 minutes).

      STUDY PROTOCOL: OUTCOME MEASUREMENTS

      The primary outcome will be the pain score in the PACU at 30 30 minutes using a sensorimotor
      composite scale:

      Performance time, sensorimotorSensory function, Onset time

      The blinded investigator will also assess the presence of hemidiaphragmatic block at 30
      minutes. A 2-6 MHz curvilinear US probe (Sonosite M-Turbo, SonoSite Inc, Bothell, WA, USA)
      and the M-mode will be employed in all subjects; the liver and spleen will serve as acoustic
      windows on the right and left side, respectively. Patients will be scanned along the anterior
      axillary line and the US probe, angled cranially

      POTENTIAL BENEFITS OF THE STUDY This study will allow us to determine if ICB-SSB constitutes
      a viable alternative to ISB.

      POTENTIAL SIDE EFFECTS OF THE STUDY Participation in this protocol will not put patients at
      higher risk for complications since ISB and ICB-SSB are commonly used to provide analgesia
      for shoulder surgery
    

Intervention name(s): Interscalene block; Infraclavicular-suprascapular block
Intervention type(s): Procedure; Procedure
Intervention description(s): Ultrasound guided single shot block above the clavicle; Combined block of nerves far away from phrenic nerve
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Outcomes Assessor)
Primary purpose: Supportive Care