Download Paravertebral Blocks

PARAVERTEBRAL BLOCKS
Indication
 Unilateral procedures involving the trunk or pelvis
Anatomy
Copyright 2004, Icon Learning Systems, LLC. A subsidiary of MediMedia, USA, Inc. All rights reserved.
Copyright 2004, Icon Learning Systems, LLC. A subsidiary of MediMedia, USA, Inc. All rights reserved.
 The thoracic paravertebral space is defined anterolaterally by the parietal pleura,
posteriorly by the superior costotransverse ligament, medially by the vertebra and
superiorly and inferiorly by the heads and necks of adjoining ribs.
 The lumbar paravertebral space is defined anterolaterally by the psoas muscle and
medially by the vertebra.
Needle
 22G 100mm Tuohy needle attached with sterile tubing to the syringe containing local
anesthetic
Position
 Patient sitting, leaning slightly forward with the chin on the chest to flex the cervical and
thoracic spine.
Procedure
 Find the C7 vertebra. This is the most prominent cervical vertebra in the neck. Mark the
superior aspect of C7
 Working caudally count and mark the vertebrae below.
 From the mid-point of the superior aspect of each spinous process, measure 2.5cm
laterally and mark these points. This will generally overly the caudad portion of the
transverse process of the vertebra below.
 Because of the extreme angulation of the spinous process a line lateral will overly the
transverse process of the vertebra below. (i.e. a line lateral to the T3 spinous process
overlies the transverse process of T4). This is true till T8 or T9.
 After prepping the skin, inject the needle insertion site with lidocaine containing
epinephrine using a 27G needle. Attempt to contact the transverse process with the 27G
needle. This will help judge the depth and position of the transverse process.
 Insert the Tuohy needle perpendicular to the skin a distance of 2-4cm (more in the obese)
to contact the transverse process. If the transverse process is not contacted at an
appropriate depth do not go deeper. The needle is likely between two transverse
processes. Withdraw the needle and redirect either cephalad or caudad until the
transverse process is contacted.
 Once contact with the transverse process at an appropriate depth is made is made,
measure and mark the distance. The depth of the subsequent transverse processes will be
approximately the same.
 If bone is contacted at a point which seems too deep the needle is likely on the rib
anterior to the transverse process.
 The transverse processes of T1 and T2 are slightly deeper due to overlying neck muscles
and ligaments.
 Once the transverse process is contacted the needle is then withdrawn to the skin, and reinserted to "walk off" the inferior aspect of the transverse process.
 Once the needle is successfully advanced past the transverse process it should be
advanced 1cm in the thoracic spine and 0.5cm in the lumbar spine.
 After negative aspiration, 5ml of local anesthetic is injected at each level.
Local Anesthetic
 Ropivacaine 0.5% or 0.75% with 1:400,000 epi, 5-8ml per level
Suggested level of blockade by procedure
 Needle localized breast biopsy
 Simple Mastectomy
 Radical Mastectomy
T2-T4
T2-T6
T1-T6
 Iliac Crest Graft
T11, T12, ↕L1
 Inguinal Hernia
T11, ↕T12, ↕L1, L2
↕ = Inject above and below the transverse process
Comments
 Resistance on injection is likely due the needle tip being in the superior costotransverse
ligament. The needle should be advanced 1-2mm.
 The syringe should never be disconnected from the tubing while performing the block.
The needle tip can inadvertently be in the pleural cavity, which can cause a
pneumothorax if the tubing is opened to air.
 With adequate subcutaneous injection of lidocaine, this block is not associated with
significant discomfort.