Photonic Needle and Paravertebral Space Detection
Condition: Anesthesia
Study type: Observational

Summary: 
      For effective anesthesia and interventional pain treatments, correct needle placement is
      crucial. Currently used methods to guide needle placement and confirm the actual treatment
      location before injection of the medication include: image-guidance, loss-of-resistance, and
      electrical stimulation. However, accuracy of needle placement could be improved if
      information would be available that would complement the current methods. We have developed
      the so-called "photonic needle" technology based on optical spectroscopy that has the
      potential to provide such complementary information.

      This study is an observational study in a limited number of patients. A common
      ultrasound-guided regional anesthesia procedure has been selected, during which data will be
      acquired with the photonic needles at a number of points along the needle trajectory that
      allow for confirmation by imaging.

      Rationale for this study is to investigate the potential of the technology to discriminate
      tissues that are relevant to distinguish during the procedure.
    

Detailed description: 
      The primary objective of the trial is to investigate if the photonic needle technology can
      reliably identify the thoracic paravertebral space. Diffuse reflectance spectra will be
      acquired during needle advancement, with custom-made needle stylets that contain optical
      fibers.

      Main study parameters are:

        1. Successfully acquired diffuse reflectance spectra obtained in the thoracic paravertebral
           space, and spectra obtained during needle advancement.

        2. Confirmation of sonographic thoracic paravertebral localization, defined as tissue
           imaging in all locations of the needle where the diffuse reflectance spectra have been
           collected .

        3. Recordings of reaction to a small test dose of lidocaine 2% with epinephrine 1:200.000
           at target position for regional anesthesia (to exclude vascular localization of the
           needle)

        4. "certainty score" on a 3-point scale (1 = uncertain, 2 = certain, 3 = very certain)
           provided by the physician for assignment of the type of tissue present at the needle
           tip, based on the information available from imaging and/or aspiration and/or reaction
           to a small injection of epinephrineOther study parameters

      The endpoint of the study is a statistical analysis of the difference between diffuse
      reflectance spectra obtained at non-paravertebral and paravertebral measurement locations.
    

Intervention name(s): thoracic surgery
Intervention type(s): Procedure
Intervention description(s): unilateral thoracic surgery under paravertebral block and general anesthesia
Observational model: Cohort
Time perspective: Cross-Sectional
Sampling method: Non-Probability Sample
Study population: 
        Patients scheduled for elective unilateral thoracic surgery under paravertebral block and
        general anesthesia
      
Keywords: paravertebral space; needle placement; tissue identification; regional