Efficacy of Ultrasound Guided ESP Vs Video-assisted PVB Catheter Placement in Minimally Invasive Thoracic Surgery
Condition: Regional Anesthesia Morbidity; Pain, Postoperative; Pain, Chronic
MeSH terms: Pain, Postoperative; Chronic Pain
Study type: Interventional

Summary: 
      Minimally Invasive Thoracic Surgery (MITS) is a surgical method used to perform lung surgery
      through small incisions between the ribs and includes both Video-Assisted Thoracic Surgery
      (VATS) and Robotic assisted Thoracic Surgery (RATS). MITS can cause a significant amount of
      postoperative pain and if this is not adequately controlled, it can delay the patient's
      recovery and it may be a precipitating factor for the development of Chronic Persistent
      Surgical Pain (CPSP).

      Regional anaesthesia is the use of nerve numbing medications known as local anaesthetics to
      block sensations of pain from a specific area of the body. For MITS, blocking pain arising
      from the chest wall/rib cage would improve the patient's recovery after the operation and
      overall patient satisfaction.

      There have been significant advancements made in thoracic (chest wall) regional anaesthesia
      techniques. Ultimately, this involves injecting local anaesthetics around the nerves that
      supply the chest wall. A single injection of these medications will only have a maximum
      effect for up to 12 hours and often this is considerably less. To prolong the pain free
      benefit, a thin tube known as a catheter will be placed so that the local anaesthesia
      medication can be continuously given by a specific mechanical pump designed for this purpose.
      This mechanical pump will be located at the patient's bedside and can precisely deliver the
      medication in question at a rate between 10-15 ml/hr. This infusion of local anaesthesia
      medication will continue for 48 hours after the operation and will be monitored by the
      hospital's pain team.

      The primary aim of this study is to compare the efficacy of two techniques for thoracic
      regional anaesthesia after this type of surgery. Participants will be randomly assigned (like
      tossing a coin) to receive either an Anaesthesiologist ultrasound guided Erector Spinae Plane
      Block (ESP) with catheter insertion or surgeon video-assisted Paravertebral block (PVB) with
      catheter insertion. Both these regional anaesthesia techniques are well established in
      clinical practice, but there is little evidence published comparing them for this type of
      surgery, in terms of quality of patient's short term (1-2 days) and longer-term (3 months)
      recovery.
    

Detailed description: 
      Erector Spinae Plane (ESP) block has emerged as a new regional anaesthesia technique which
      has had promising early results in attenuating severe acute pain associated with Minimal
      Invasive Thoracic Surgery (MITS). In a recent randomised control trial among MITS patients,
      single-shot ESP block improved Quality of Recovery score (QoR-15) and reduced overall
      complications at 24 hr compared with single-shot serratus anterior plane block (SAP).

      Paravertebral block (PVB) has been widely used for analgesia after thoracic surgery for over
      two decades because it reduces postoperative pain and opioid requirements. When compared with
      systemic analgesia and alongside with epidural analgesia, it is considered the "gold
      standard" for thoracic regional analgesia techniques. Both ESP and PVB have usually been
      described as a single-shot technique. However, catheter techniques offer the prospect of
      flexibility and prolonged analgesia.

      Placement of a thoracic PVB catheter can be achieved by an anatomical landmark or ultrasound
      technique. Ultrasound technique has a higher success rate and safer profile when compared to
      the landmark technique but is technically challenging. However, in MITS an opportunity arises
      for directly visualised placement of a PVB catheter by the surgeon under thoracoscopic
      guidance. Insertion of the PVB catheter and verification by the surgeon under direct vision
      could be a more reliable and safer method, but there are limited randomised controlled trials
      examining the efficacy of this technique. Also, there are limited clinical effectiveness
      trials on the catheter-based ESP analgesia technique using patient-centred outcomes.
      Furthermore, no study has evaluated the effect of acute analgesia over 24-48 hr with
      continuous regional nerve block on CPSP at 3 months after MITS.

      Therefore, the investigators aim to complete a multicentre, prospective, double-blinded,
      randomised controlled clinical trial to test the hypothesis that
      Anaesthesiologist-administered, ultrasound guided ESP catheter analgesia is equivalent to
      surgeon-administered, video-assisted PVB catheter analgesia, in terms of early recovery
      (QoR-15), respiratory spirometric function at 24-48 hr, and CPSP at 3 months after MITS
      surgery.

      Study setting: This study will take place between three level four academic hospitals in the
      Republic of Ireland (Mater Misericordiae Univeristy Hospital-MMUH, St Vincent's University
      Hospital-SVUH and St Jame's University Hospital-SJH).

      Standard of care: Standard of care will be identical in both groups. The only difference will
      be that one group will receive an anaesthesiologist ultrasound guided placement of an erector
      spinae (ESP) catheter and the other will receive a surgeon video-assisted placement of a
      paravertebral block (PVB) catheter. Patients in both groups will be given a general
      anaesthetic as part of their care. All patients will be intubated with a double-lumen
      endotracheal tube and a radial arterial line will be sited for continuous haemodynamic
      monitoring. Venous access will be at the discretion of the consultant anaesthesiologist. The
      haemodynamic goal will be to maintain a systolic blood pressure within 20% of baseline and to
      avoid a heart rate greater than 100 beats per minute. Persistent hypertension and or
      tachycardia above this point will trigger an opioid (oxycodone, morphine or fentanyl) to be
      given intravenously. The frequency and dosage of this will be at the discretion of the
      anaesthesiology team.

      Study intervention: Participants will be randomised into either the ESP or PVB group. No
      other forms of regional analgesia techniques (e.g. Intrathecal opioids, epidural analgesia,
      and subcutaneous infiltration of local anaesthetic) will be used during this trial.

      Safety reporting: Any unexpected complications that may arise from this trial will be
      documented and reported to the principal investigator, surgical consultant and the relevant
      hospital patient safety board.

      Sample size and justification: The primary outcome will be the QoR-15 score at 24 hours post
      operatively. The established minimum clinically important difference in QoR-15 is 8.0 and the
      SD of QoR-15 scores is typically between 10-16. [range of QoR score is 1-150]. We have chosen
      a SD of 12 to reflect our study population. Therefore, assuming Type I error = 0.05 and Type
      II error = 0.2 (80% power to detect this difference), then n=36 patients will be required in
      each group. We aim to enroll n=40 each group to allow for loss to follow up, missing data or
      withdrawal of consent.

      Recruitment: Potential participants for this trial will be identified by a member of the
      surgical, anaesthetic or research team. A list of patients scheduled to have MITS will be
      made available the day before the procedure. These patients' electronic medical records will
      undergo a preliminary review to determine if they are potential candidates for this trial,
      i.e. if participants meet the inclusion criteria and have no exclusions.

      The suitable patient will be approached the evening before surgery if available.
      Alternatively, patients will be approached on the ward on the morning of surgery and their
      suitability to participate in the trial will be confirmed. The purpose of the trial,
      peripheral nerve blocks (including benefits and risks) and method of follow up will be
      explained to the patient. A comprehensive and informative leaflet will be given to each
      patient and they will be afforded an adequate amount of time (minimum 10 mins) to study it.
      Participants will be informed that their participation in the study is entirely voluntary and
      they will have the opportunity to withdraw from the study at any time and this will not
      affect the quality of care they receive. Following this, participants will be offered an
      opportunity to ask any relevant questions and voice any potential concerns. If he/she
      professes an interest in participating in the trial written consent will be obtained. This
      process will be completed before transferring the patient to the theatre environment.

      Study participants will be followed on Day 1 and Day 2 postoperatively for QoR-15 and
      spirometric score. A member of the research team will phone the patient at 3 months after the
      date of surgery and they will be asked to complete two questionnaires to assess for CPSP (BPI
      and SF-12)

      Record Keeping: All patient data collected will be handled in accordance with European Union
      General Data Protection Regulations (EU 2016/679). Data will be initially collected manually
      and then transcribed onto Microsoft excel. Data collected from each hospital site will be
      stored securely in the Department of Anaesthesiology at the respective hospital, on a
      password-protected desktop computer stored in a locked office, such that only investigators
      assigned to data processing and analysis will have access to.

      Statistical analysis: The collected raw data will be initially inspected for any errors, this
      includes but is not limited to double-entry errors, missing data and data that was
      incorrectly entered. Patients with missing or incorrect data will be excluded from the trial
      and this data will not be included in the final analysis. The data will be tested for normal
      distribution according to the Shapiro-Wilk test. Normally distributed data will be compared
      between the two groups using the unpaired student t-test and non-normal distributed data will
      be compared by using Mann-Whitney U test. All data will be summarised as mean + standard
      deviation and p value <0.05 will be considered statistically significant.

      Financing and Insurance/Indemnity: Investigators in each hospital will be covered by the
      clinical indemnity scheme (CIS). No funding has been sought to conduct this clinical trial.
      Existing resources available to the investigators are sufficient to meet the aims of the
      study.
    

Intervention name(s): Anaesthesiologist-administered ultrasound guided Erector Spinae block with catheter insertion; Surgeon-administered video-assisted Paravertebral block with catheter insertion
Intervention type(s): Procedure; Procedure
Intervention description(s): Erector Spinae block: A bolus of 20 ml 0.375% Levobupivacaine will be administered into the erector spinae plane prior to surgical incision. A further bolus of 10 ml 0.25% Levobupivacaine will be given at skin closure if it has been greater than 1 hour after the first bolus of local anaesthetic medication. A continuous infusion of 0.125% Levobupivacaine will be commenced via the sited nerve catheter for postoperative analgesia. This will be started at 10 ml/hr and titrated to effect to a maximum rate of 15 ml/hr.; Paravertebral block: A bolus of 20 ml 0.375% Levobupivacaine will be administered into the paravertebral space after the thoracoscopic ports have been sited. A further bolus of 10 ml 0.25% Levobupivacaine will be given at skin closure if it has been greater than 1 hour after the first bolus of local anaesthetic medication. A continuous infusion of 0.125% Levobupivacaine will be commenced via the sited nerve catheter for postoperative analgesia. This will be started at 10 ml/hr and titrated to effect to a maximum rate of 15 ml/hr.
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: This will be a multicentre, prospective, double-blinded, randomised controlled clinical trial. This study will take place between three level four academic hospitals in Co.Dublin, Ireland. One group will receive an Anaesthesiologist-administered, ultrasound guided erector spinae plane catheter and the other group will receive a surgeon-administered, video-assisted paravertebral catheter.
Masking: Double (Participant, Outcomes Assessor)
Primary purpose: Treatment
Keywords: Regional Anesthesia; Erector Spinae Block; Thoracic Paravertebral Block; Quality of Recovery; Chronic Persistent Surgical Pain