++++
Catheter infusions often use 0.125% bupivacaine or 0.2% ropivacaine (less motor block), although some practitioners use higher or lower concentrations.
++
Infusion rates should be adjusted for optimal analgesia and to limit motor block that can interfere with physical therapy.
++
- Inadequate analgesia:
- Intravenous or oral analgesics may be needed for pain in areas not covered by the block. Typically, brachial plexus blocks should cover the full area of the surgery, while lower extremity blocks might not (e.g., lumbar plexus block for THA or femoral block for TKA will not cover areas innervated by the sciatic nerve)
- Assess for catheter dislodgement or disconnection
- Give a 5–15 mL bolus of local anesthetic (fractionated). Reassess after 15–20 minutes
- Consider replacing the catheter or using alternative forms of analgesia
- Dislodgement:
- Methods to secure catheters include the following:
- Benzoin or other topical adhesive is placed around the catheter entry site. Skin adhesive strips and a clear occlusive dressing are placed on the adhesive
- A stabilization device may be used
- Tunneling or suturing may be considered
- Leakage at insertion site:
- There may be some minimal leakage at the insertion site as local anesthetic can track along the catheter. The dressing can be reinforced
- Leakage may also occur if there is dislodgement of the catheter
- Blood in/around catheter:
- Assess for intravascular catheter migration. Monitor the patient for signs and symptoms of local anesthetic systemic toxicity
- Excessive numbness/motor block:
- Reduce the infusion rate and reassess the patient within an hour
- If pain control is inadequate with lower infusions, discuss with patient alternative forms of analgesia versus increasing infusion rate again
- If numbness or motor block is persistent, consider nerve injury and/or hematoma (see the section “Complications”)
++
- There are no clear recommendations
- Current ASRA guidelines recommend for deep plexus or peripheral block using the same guidelines for neuraxial anesthesia (Grade 1C recommendation): see chapter 119
- Retrospective studies suggest these guidelines may be too strict, but further studies are needed
++
- Bleeding:
- Pain, neurological deficit, drop in hematocrit
- Imaging such as CT
- Supportive therapy, surgical consultation
- Neurological injury (see chapter 129):
- Symptoms normally noted after block recedes: numbness, weakness, pain, paresthesias
- Rule out bleeding or vascular injury. If bleeding, surgical consultation and supportive therapy
- For minor deficits, schedule follow-up. If deficit does not resolve, consult neurology
- For major deficits, consult neurology (possible EMG/NCS). Supportive therapy such as PT/OT
- Infection:
- Risk factors:
- ICU stay
- Catheter in place >48 hours (but with impeccable care, catheters have been kept in place for weeks, e.g., in combat ...