Rib Blocks for Trauma

Flail chest and the pulmonary contusions that almost always accompany these chest wall injuries leads to dysfunctional pulmonary mechanics and physiology- including loss of tidal volumes and V/Q mismatch.

Management of flail chest is highly dependent on early, adequate pain control. The patient's subjective report of significant pain is the only necessary indication for further intervention. But in patients with flail chest, there is evidence to show a strong relationship between pain control and patient outcomes and in large part can be attributed to the ability for patients to adequately clear secretions. This can mean faster, more successful liberation from mechanical ventilation or even preventing it altogether.

Along with parenteral opioids, local, spinal or epidural anesthesia can be used. For one of our patients, we recently employed a regional intercostal nerve block as an initial step for better pain control. Below is a review of regional intercostal nerve blocks and how we did it:

Indications:

• 
  
  Relief pain from injuries (including iatrogenic) that can be attributed to nociceptive pathways of the intercostal nerves

Contraindications:

• 
  
  Pain to severe to be controlled with local anesthesia (relative)
• 
  
  Allergy to anesthetic

Equipment:

• 
  
  Hypodermic needle
• 
  
  Syringe
• 
  
  Long-acting local anesthetic (we used 0.5% bupivicaine)

Positioning

• 
  
  lateral decubitus positioning, positioned contralateral to affected side (our patient's fractures were all on his left side, so we positioned him in right lateral decubitus)

OR

• 
  
  Sitting with torso flexed

Technique:

• 
  
  Clean skin with chlorhexidine
• 
  
  With non-dominant hand, palpate the spinous processes at level of affected ribs
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  Palpate laterally, past the paraspinous muscles until you can feel bony rib and its superior and inferior borders
• 
  
  Insert needle into the skin just superficial to the rib and continue until you feel the needle tip hit the ribs body
• 
  
  Angle the needle inferiorly and march the needle down and march the needle tip down until you are just inferior to the rib's inferior edge (much the way you would find the subclavian vein when doing a central venous line)
• 
  
  ASPIRATE so that you know that you are not in either the vein or the artery
• 
  
  Inject
• 
  
  Repeat the above steps for the affected ribs

A few notes:

1. 
   
   Since the needle is at the inferior rib border, it's much easier to inject anesthetic where you don't want it
2. 
   
   This is really only a temporary solution and should only be used to temporize until a more definitive method can be done (e.g. epidural)
3. 
   
   According to some texts, the anesthetic disperses radially and can even enter the epidural space, so don't worry if it doesn't work initially
4. 
   
   Make sure you know the safety profile and max dosing for the anesthetic you use. We all know the maximum doses for lidocaine ad nauseum, but it's not appropriate in this setting.

Thanks to Dr. Allan Peetz for this post.