Chapter 162. Epidural Analgesia

• Superior pain relief when compared with IV PCA, subcutaneous and oral analgesics
• Superior static and dynamic (mechanical) analgesia and hence improved mechanical DVT prophylaxis
• Improved mobilization and physical rehabilitation
• Improved pulmonary function
• Earlier return of postoperative bowel function
• Increased extremity perfusion due to vasodilatation and reduced platelet aggregation
• Reduced risk of complications related to immobility
• No evidence of decreased cognitive dysfunction in elderly patients

• Coagulopathy: functional platelet abnormalities; platelets <80,000; elevated PT, PTT, and INR. Antiplatelet medications. See chapter 119 for more information
• Sepsis, local, or systemic infection
• Surgeons often request no regional analgesia when there is a concern of possible compartment syndrome (e.g., tibial plateau fracture). However, there is no evidence in the literature to support the claim that diagnosis could be delayed by regional analgesia

• Check all connections, tubing, and pump function
• Check catheter insertion and measurement at the skin (a transparent dressing makes this easier). Determine if catheter has pulled out of the epidural space
• Aspirate the epidural catheter for blood or cerebrospinal fluid (CSF)
  • If blood return, the epidural catheter can be pulled back 0.5–1 cm and reaspirated
  • If CSF return, remove epidural and consider epidural catheter replacement
• Consider rebolusing the epidural after the catheter has been pulled back and aspirate is negative

Test dose with 3 mL 1.5% lidocaine with epinephrine 1:200,000

• If there is an increase in heart rate (≥10 bpm) or blood pressure (SBP increase by ≥15 mm Hg), or an increase in T-wave amplitude by more than 25%, the catheter is likely intravascular
• If there is profound sensory or motor block in the abdomen and extremities within 5 minutes, the catheter is in the subarachnoid space
• If there is an abdominal sensory level (for a lumbar placement), the catheter is in the epidural space. That is not always obtained with such a small dose
• Please note: subarachnoid and epidural placements are often associated with a drop in blood pressure following test dose administration

The more hydrophilic the opioid, the more cephalad spread will be seen, with the risk of respiratory depression.

Fentanyl/bupivacaine:

Fentanyl/ropivacaine:

• Spread depends on volume; typically the volume that will block 1 lumbar dermatome will block only 0.7 thoracic dermatome and 2 cervical dermatomes: 1L = 0.7T ...