Comparing Efficacity of Analgesia Between Ultrasound-guided Nerve Block and Local Infiltration After Wrist Fracture Surgery
Condition: Postoperative Pain; Wrist Fracture
MeSH terms: Pain, Postoperative; Fractures, Bone; Wrist Fractures
Study type: Interventional

Summary: 
      Distal radial fracture reparations by volar plating are often managed under regional
      anaesthesia, but are associated with severe pain when the block ends. Acute post-operative
      pain may delay rehabilitation, and even be a risk factor for the development of chronic pain.
      The use of opioids and the inevitable opioid-related side effects further decrease patient
      satisfaction. A multimodal approach to pain management should include local or regional
      analgesia technique when possible. In the case of wrist fractures, two methods are available:
      peripheral nerve block by the anaesthesiologist or surgical site local infiltration by the
      surgeon with a long-acting local aesthetic. Both techniques are commonly used for the
      management of postoperative pain after diverse orthopaedic surgeries.

      The purpose of this study was to determine the equivalence between ultrasound-guided
      peripheral nerve block and local infiltration by the surgeon for short-term postoperative
      analgesia after surgical reparation of isolated closed wrist fractures by volar plating under
      regional anaesthesia. The quality of postoperative pain, patient satisfaction and adverse
      events were recorded for the first 48 hours following surgery.
    

Detailed description: 
      Patients were allocated to treatment group according to a computer-generated randomisation
      sequence by blocs. Randomization was obtained and all data recorded through an electronic
      report form (URC Robert Debre).

      Demographic and medical information were obtained in a pre-operative anaesthesia consultation
      kept with the rest of the patient's written file.

      All interventions were carried out under regional anaesthesia consisting of an
      ultrasound-guided axillary block with 25-35 mL of lidocaine 1,5% with epinephrine, targeting
      the median, ulnar, radial, musculocutaneous and lateral cutaneous nerves. The analgesic
      intervention was realised according to group allocation, at the end of surgery: after skin
      closure and before making the cast. To ensure the blinding of the patient, the surgical
      sterile drapes were kept until the end of the analgesic intervention

        -  In the peripheral nerve block group (BN), the anaesthesiologist performed an
           ultrasound-guided block of the median and radial nerves at the lower third of the arm.
           Each nerve was encircled with 10 mL of ropivacaine 0,475%.

        -  In the local infiltration group (INF), the surgeon injected 10mL of ropivacaine 0,75%
           directly all peri-fracture tissues: fracture site, tendon synovial sheaths hypodermis
           and dermis regarding surgical incision.

      An operating room or aesthetic nurse timed the duration of realisation of the analgesic
      intervention.

      The intensity of proximal motor nerve block was recorded before patient discharge from the
      post anaesthesia care unit, using a modified Bromage Scale.

      In each group the pain management was standardised: in the post anaesthesia care unit (PACU)
      the patients received 1g of acetaminophen and 550mg of naproxen (NSAID) as well as 20 mg
      omeprazole given orally. This treatment was continued in the orthopaedic ward, every 6 hours
      for acetaminophen, 12 hours for naproxen and every day for omeprazole. If the pain score
      reached 3/10, rescue medication was given: 10 mg of oral morphine sulphate, available every 6
      hours. Upon discharge, the patient was given a prescription with these same medications for
      two days and clear instructions on the use of rescue opioids.

      The patient was asked to record pain scores at 3, 6, 12, 24, 36 and 48 hours, opioid
      consumption, opioid related adverse events, quality of sleep and satisfaction with pain
      management on a document intended for this purpose.

      The pain scores were recorded using a Numeric Rating scale for pain ranging from 0 (no pain)
      to 10 (worst possible pain). Total opioid consumption was assessed in milligrams. Quality of
      sleep as well as patient satisfaction with pain management were recorded using a numerical
      rating scale ranging from 0 to 10.

      Interns or medical practitioners unaware of patient allocation then collected the data. If
      the patient was discharged within 2 days, data was recovered by telephone. The anonymized
      data was then recorded in the electronic report form. All electronic data was declared to the
      CNIL (French National Committee for Data protection and Liberties).

      According to our preliminary data, the standard deviation of the mean duration of analgesia
      for the first 48 postoperative hours was 108 minutes. We chose to set the equivalence margin
      at 90 minutes, as it seemed clinically relevant to describe a difference in duration of
      analgesia for the patient. With a risk alpha = 5% and beta = 10% and 10% of patients expected
      not assessable, the estimated number of patients to include was 72 (36 in each group).

      As this study aims to show equivalence, a per-protocol analysis will be carried out in first
      intention. An intention-to-treat analysis will follow to assess the results' reliability and
      treatment's efficiency.

      Patient characteristics will be described for the two groups.

      The primary study endpoint was the delay between analgesic intervention and occurrence of a
      pain score greater than 3/10 during the first 48 postoperative hours. The equivalence margin
      of 90 minutes was considered clinically relevant, defining an equivalence interval between
      -90 and + 90 minutes. If the confidence interval of the difference in analgesia duration
      between the two techniques is included in this interval, the two techniques will be
      considered equivalent. On the contrary if the confidence interval of the difference is only
      partially included of not included in this interval, we will conclude to non-equivalence.

      The secondary end-points will be included in a superiority analysis.

        -  The mean difference for the duration of realisation of analgesic intervention will be
           compared using Student's t-test or a non-parametric test.

        -  The intensity of proximal motor block assessed by modified Bromage Scale will be
           compared using a chi-squared test or Fischer's exact test.

        -  The number of patients with a numerical pain rating ≤ 3, the number of patients
           requiring opioids, the frequency of opioid-related adverse events during the first 48
           postoperative hours and the quality of sleep on the first night on a numeric scale from
           0 to 10 will be compared using a chi-squared test or Fischer's exact test.

        -  Total opioid consumption (in milligrams) as well as patient satisfaction with pain
           management during the first 48 postoperative hours will be compared using Student's
           t-test or a non-parametric test.

        -  The pain scores recorded at 3, 6, 12, 24, 36 and 48 hours postoperatively will be
           described with a graphic analysis and compared using a mixed model reflecting the
           repeated measures.
    

Intervention name(s): Local infiltration anesthesia
Intervention type(s): Procedure
Intervention description(s): Local infiltration by the surgeon at the end of surgery of perifracture site. A solution of 10 mL of ropivacaïne 0,75% is injected in the fracture site, tendon's synovial sheaths, subcutaneous tissue and skin.
Intervention MeSH terms: Anesthetics
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Outcomes Assessor)
Primary purpose: Treatment
Keywords: Wrist fracture; postoperative pain; local anesthesia