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Paravertebral Nerve Block Paravertebral Nerve Block Indica�ons: Rib fractures, breast surgery, thoracic surgery, unilateral abdominal surgery, hernia repair. Benefits: Less hypotension than epidurals, poten�al for outpa�ent use Complica�ons( <2.6%): Epidural spread, paraspinal muscle spasm, Brachial plexus block, pressure parathesia, pneumothorax. Breast surgery: General anesthesia vs associa�on with PONV.
PVB vs Epidural for Thoracotomy
Less hypotension with PVBs
Pintaric et al, RAPM 2011
Paravertebral Nerve Block: In-‐plane approach
Paravertebral: Rib vs. Pleura Paravertebral: Probe Posi�on Transverse Process Pleura
Move probe slightly caudal to obtain pleura only (no transverse process) Now probe is exactly intercostal Intercostal muscles Pleura
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Paravertebral: Probe Posi�on In-‐Plane Paravertebral Nerve Block
Pleura
MEDIAL
LATERAL
Endothoracic fascia
Paramedian Saggital Scanning: Probe Posi�on
Parasaggital In-‐Plane Paravertebral Block
CAUDAL
CRANIAL
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Parasaggital In-‐Plane Paravertebral Block
CAUDAL
CRANIAL
Parasaggital Out-‐Of-‐Plane Paravertebral CAUDAL
CRANIAL
Paravertebral Spread: Endothoracic fascia
If underneath the endothoracic fascia, the longitudinal spread pattern is observed. Njaa et al, Anaesthesia 2004
Out-‐of-‐Plane Paravertebral Block
Glue Secure with Dressings
Paravertebral Details o Primary Anesthe�c
– Mul�ple injec�on technique, every level works best – 5 – 10mL at each level – 0.5%-‐1% Ropivacaine with 1:400,000 epi – Be wary of rapid systemic absorp�on
o Catheters – Put catheter in middle of incision – Example: T4 catheter for mastectomy – Run at 6-‐10mL/hr
o Post op pain – Single Injec�on – Ok to skip levels (example: T2, T4, T6) – Injec�on of larger volumes (10-‐25mL) – Error above the target site (injectate spreads preferen�ally caudal) – 8-‐24 hours analgesia
Paravertebral Absorp�on
Use epinephrine to delay absorption. Karmakar 2005 et al, Anesthesiology 2005
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Paravertebral Spread
Larger volume / kg resulted in more spread. Njaa et al, Anaesthesia 2004
Paravertebral Spread
20mL injectate resulted in 3-4 level spread on MRI. Marhofer et al, Anesthesiology 2013
Paravertebral Spread
Spread is highly variable and multiple injections work best for full coverage. Cowie et al, Anesth Analg 2010