Ultrasound Prescan vs Conventional Landmark-guided Technique in Spinal Anesthesia in Orthopedic Obese Patients
Condition: Ultrasonography; Anesthesia, Spinal; Body Mass Index; Obesity
Study type: Interventional

Summary: 
      The study is aimed at evaluating whether ultrasound pre-procedural scan with Accuro may
      reduce needle redirections when performing spinal injection in patients with BMI = or > 30 in
      orthopedic surgery
    

Detailed description: 
      This is a open-label randomised controlled study.

      90 patients will be recruited and divided into two groups of 45 patients per group.

      Patient recruitment will be performed by patient visit and checking inclusions and exclusion
      criteria. After written informed consent, every single patient will be allocated in one of
      the two groups following a computer generated randomization list.

      Patients in both groups will undergo:

        -  standard monitoring with Non Invasive Blood Pressure (NIBP) cuff, three-lead
           electrocardiography (ECG) and Pulse-oximetry (SpO2).

        -  Peripheral intravenous access

        -  Sedation (as prescribed by the OR anesthesiologist)

        -  Spinal anesthesia performed by anesthesiologists skilled in both techniques
           (conventional landmark technique or Accuro guided) at the L3-L4, L4-L5 or L5-S1 level,
           with a 25 or 27 Gauge needle, with the surgical side declive or proclive according to
           the baricity of the local anesthetic used (sitting position, when needed, will be
           reported in the CRF)

      In both groups an observer will monitor and register spinal procedure duration (starting
      point: anesthesiologist wearing sterile gloves, ending point: end of local anesthetic
      injection).

      Control group (landmark technique):

      The anesthesiologist will identify lumbar spinous processes with traditional landmark
      palpation. Once the correct interspinous level and the mid-line will be identified, the
      anesthesiologist will proceed with needle insertion and spinal injection.

      Treatment group (ultrasound pre-procedural scan with Accuro):

      By using Accuro US probe the anesthesiologist will perform a pre-procedural lumbar spine scan
      to detect the needle entry site. After image optimization, the Accuro probe will be aligned
      with the spine mid-line, as indicated by a dashed red-line on the screen. After that the
      interlaminar space at the desired intervertebral level will be detected, as indicated by
      orange overlay in the screen. The depth and the device angle used to detect the interlaminar
      space will be annotated. The anesthesiologist will then disengage the Accuro Locator needle
      guide and press gently against the skin. Then the probe will be removed and the spinal
      injection will be performed.
    

Intervention name(s): Accuro; cutaneous landmarks
Intervention type(s): Device; Procedure
Intervention description(s): spinal anesthesia injection based on identification of entry site with pre-procedural ultrasound scan with Accuro device; spinal anesthesia injection based on identification of entry site with palpation of cutaneous landmarks
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Other