Sub-Paraspinal Block in Nuss Patients. A Pilot Project
Condition: Pectus Excavatum; Pain, Postoperative
MeSH terms: Funnel Chest; Pain, Postoperative
Study type: Interventional
Phase: Phase 4

Summary: 
      The purpose of this pilot study was to evaluate effectiveness of a novel regional anesthesia
      technique developed at the investigators institution, as part of a quality improvement
      initiative, to assist with multilevel thoracic pain control in post-Nuss procedure patients.
      The investigators hypothesized that the local anesthetic infusion via bilateral
      multiperforated soaker catheters placed at extrathoracic sub-paraspinal muscle location under
      ultrasound guidance would significantly improve pain control, as reflected by the decrease in
      pain intensity score, reduction in opiate requirement and improvement infunctional
      rehabilitation measure scores in patients who underwent the Nuss procedure for pectus
      excavatum repair. However, the goal of this pilot study was not to detect a statistically
      significant difference in the primary outcomes between control and treatment groups (as the
      number of study subjects was chosen out of necessity of what could be completed within a
      specified time period), but to estimate the parameters which allows appropriate power and
      sample size calculations for a future multi-institutional study.
    

Detailed description: 
      This study underwent initial peer review by the Biomedical Research Committee at Nemours and
      was awarded internal funding by the Nemours Funding committee. Scientific progress review was
      conducted annually and was the basis for subsequent year funding.

      Ten eligible patients were recruited and allocated into one of two groups according to a
      computer generated random allocation table: five patients allocated to the treatment group
      received bilateral ultrasound-guided placement of multi-perforated soaker catheter at
      sub-paraspinal location and an intravenous PCA post-operatively; five patients allocated to
      the control group had two sham multi-perforated soaker catheters taped to their back and
      received intravenous PCA post-operatively. In the treatment group, catheter position was
      considered adequate when live ultrasound imaging confirmed placement directly over the rib
      surface and lateral to the transverse process at the T2-T10 level. A 7.5 inch On-Qr
      multi-perforated catheter was placed via each introducer for patients under 5'7'' (170.18 cm)
      and a 10" (25.4 cm) catheters was placed for those over 5'7" (170.18 cm). An infusion of
      ropivacaine 0.2% was started immediately after catheter placement via the On-Q infusion
      system at a rate of 0.25 mg/kg/hour per catheter (maximum of 8 ml/hr catheter [maximum pump
      infusion rate]). Maximum total ropivacaine infusion rate was limited to 0.5 mg/kg/hr to avoid
      toxicity. The local anesthetic infusion was stopped on post-operative day number 3 and the
      catheters removed.

      Catheters were dressed in a way that concealed insertion sites and therefore precluded pain
      observers from determining group assignment while the pumps appeared to be infusing to
      blinded viewers. The peri-operative anesthetic and surgical approach were standardized for
      this study. A single anesthesiologist and surgeon were responsible for the recruitment,
      anesthesia provision, surgical technique, and multi-perforated soaker catheters insertion.
      Post-operative pain management was carried out by a group of blinded anesthesiologists
      according to the post-operative protocol. Three recovery room nurses, six floor nurses and
      three physical therapists were selected to limit inter observer variability and educated to
      the post-operative expectations and consistent use of the pain and functional independent
      measure (FIM) scoring in this patient population. With the exception of the primary
      investigators, all other personnel were blinded to the patient's group assignment.

      The outcomes were evaluated based on the total amount of narcotic per kilogram required, pain
      scores and functional performance measures derived by physical therapists.
    

Intervention name(s): Ultrasound-guided Sub-Paraspinal Block; PCA only
Intervention type(s): Procedure; Procedure
Intervention description(s): Treatment group received bilateral ultrasound-guided placement of multi-perforated soaker catheter at sub-paraspinal location. Catheter position was considered adequate when live ultrasound imaging confirmed placement directly over the rib surface and lateral to the transverse process at the T2-T10 level. An infusion of ropivacaine 0.2% was started via the On-Q infusion system at a rate of 0.25 mg/kg/hour per catheter (maximum of 8 ml/hr catheter [maximum pump infusion rate]). The local anesthetic infusion was stopped on post-operative day number 3 and the catheters removed.; Patients received intravenous PCA post-operatively
Other intervention name(s): Patient-Controlled Analgesia
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Care Provider, Outcomes Assessor)
Primary purpose: Supportive Care
Keywords: Pain Management; Anesthesia: Nerve Block