Analgesic Efficacy of Single-shot Erector Spinae Block for Thoracic Surgery
Condition: Regional Anesthesia; Pain, Postoperative
MeSH terms: Pain, Postoperative
Study type: Interventional

Summary: 
      The erector spinae plane (ESP) block is a novel regional anesthetic technique for the
      treatment of thoracic, cervical, and abdominal pain. This pilot study aims to investigate the
      post-operative analgesic effectiveness of ultrasound guided single-shot ESP blocks for
      patients undergoing minimally invasive thoracoscopic wedge resections of the lung in
      comparison to those receiving conventional parental opioid analgesia alone. This will be
      achieved through the use of objective measures including quality the 40 point Quality of
      Recovery assessment (QoR-40) on postoperative day (POD) 1, visual-analogue pain scale (VAS)
      in the post-anesthetic care unit (PACU) and at POD 1, and oral morphine-equivalent (OME)
      opioid consumption in the PACU and at 24 hours post-operatively.
    

Detailed description: 
      Purpose To investigate the postoperative analgesic effectiveness of the ultrasound-guided ESP
      block compared to a placebo injection for patients undergoing thoracoscopic wedge resection
      of the lung.

      Hypothesis Thoracoscopic surgery patients who receive an ESP block in addition to current
      standard of care, consisting of parenteral and enteral opioids and surgical wound
      infiltration, will have a clinically significant improvement in their QoR-40 at POD 1 and
      lower pain levels, as measured by VAS in the PACU on arrival and one hour after, and on POD
      1, and OME opioid consumption in the PACU and at 24 hours post-operatively, in comparison to
      those patients who receive the current standard of care along with a placebo injection.

      Justification The ESP block is a novel regional anesthetic technique that has shown efficacy
      in the management of thoracic pain as published in numerous case reports and observational
      case series. To date, no randomized control trials exist of its efficacy in comparison to
      conventional parental opioid analgesic management. Thoracoscopic wedge resections of the lung
      are procedures not usually treated with regional analgesia techniques, but given the moderate
      pain experienced by many patients, this surgical population will serve as a proof-of-concept
      for the potential of improved post-operative analgesic and recovery profiles. Proof of
      analgesic efficacy in this setting may allow a future head-to-head comparison with more
      invasive analgesic techniques currently used for thoracic surgery such as epidural and
      paravertebral catheterizations.

      In undertaking this aim, we will measure a number of different metrics. The 40-item Quality
      of Recovery Score (QoR-40) will be our primary objective as it provides a patient-centered
      global measure of overall health in the postoperative period. It has been tested for validity
      and reliability, and has undergone quantification for the minimal clinically important
      difference. Other traditional metrics of analgesic performance including the VAS and 24-hour
      post-op OME opioid consumption will also be monitored as secondary objectives.

      Objectives

      Primary Objective:

      • Quality-of-Recovery 40 scale at POD 1.

      Secondary Objectives:

        -  Cumulative OME opioid consumption intra-operatively and through PACU, and at 24 hours
           post operatively.

        -  Visual analog pain scale assessments post-operatively in PACU on arrival, after 1 hour,
           and at POD 1.

      Research Design The study will be a prospective, single center, randomized,
      placebo-controlled pilot study requiring 2 patient visits for assessment in the PACU and on
      POD 1. One interim analysis for safety monitoring will be undertaken.

      Sample Size Calculation and Statistical Methods No prior studies have been conducted to
      calculate an exact sample size calculation. Based on similar work, we will power this study
      on an expected difference of at least 10 points on the QoR-40 and a SD of 15 when comparing
      the block to placebo. This is a clinically meaningful difference. Assuming an alpha level of
      0.05 and a power of 0.80, our sample size is 74. With a 10% dropout rate we will require
      recruitment of 82 patients. All outcomes will be analysed with the independent student
      t-test.
    

Intervention name(s): ESP block; Placebo
Intervention type(s): Procedure; Procedure
Intervention description(s): An ESP block will be performed prior to surgery for postoperative pain control; A sham ESP block will be performed before surgery in the placebo group
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Care Provider)
Primary purpose: Treatment