Paraspinal Anesthesia Technique and Procedure Guide
Critical Clarification: Terminology and Scope
The term "paraspinal anesthesia" is not a standard regional anesthesia technique in mainstream anesthesia practice. The evidence provided primarily addresses paravertebral blocks (a well-established regional technique) and spinal/neuraxial anesthesia (a completely different procedure). These are distinct techniques with different indications, anatomical targets, and clinical applications.
Based on the available evidence, I will address paravertebral block technique as this appears most relevant to the query, while noting that one study examined paraspinal infiltration for chronic pain 1.
Paravertebral Block: Technique and Clinical Application
Anatomical Approach and Needle Placement
The paralaminar approach provides superior analgesia compared to the intercostal approach for paravertebral blocks. 2
- The paralaminar technique resulted in fewer postoperative fentanyl rescue doses at 3,6,12, and 24 hours postoperatively compared to the intercostal approach 2
- The block targets the paravertebral space adjacent to the vertebral column, where spinal nerves exit the intervertebral foramina
Single-Injection vs. Multiple-Level Technique
Multiple injections (five injections from T4 to T8) versus a single injection at T6 provide similar analgesic efficacy and opioid consumption, but multiple injections are more painful and time-consuming to perform. 2
- Consider single-injection technique at the mid-level of the surgical dermatomes for efficiency without compromising analgesia 2
- Multiple-level blocks may be reserved for extensive surgical fields where single-injection spread is inadequate 2
Timing of Block Performance
The timing of paravertebral block (after incision versus at procedure end) does not significantly affect pain scores or opioid consumption. 2
- Blocks can be performed either before surgical incision or at the conclusion of surgery with equivalent efficacy 2
- Pre-incision placement may be preferred for preemptive analgesia, though evidence does not demonstrate superiority 2
Local Anesthetic Selection and Dosing
Primary Local Anesthetic Agents
Ropivacaine 2 mg/mL infused at 10-14 mL/h through a continuous catheter provides effective analgesia with lower pain scores compared to single-shot intercostal blocks. 2
- Bupivacaine 5 mg/mL is an alternative agent for single-shot paravertebral blocks 2
- For spinal anesthesia (if that is the intended technique), lidocaine provides short duration (<1 hour), while tetracaine and bupivacaine provide 2-5 hours of anesthesia 3
- Ropivacaine produces less intense motor block of shorter duration compared to levobupivacaine, advantageous for earlier mobilization 4
Adjuvant Medications
Adding dexmedetomidine to paravertebral blocks with ropivacaine reduces pain scores and may reduce opioid consumption. 2
- Dexmedetomidine combined with ropivacaine demonstrated lower pain scores in multiple studies 2
- One study showed reduction in chronic pain at 3 months (but not 6 months) when dexmedetomidine was added to bupivacaine 2
- The combination of local anesthetic with opioids (sufentanil) showed no significant difference in pain scores or opioid consumption compared to local anesthetic alone 2
Catheter Techniques and Infusion Strategies
Continuous vs. Programmed Intermittent Bolus
Programmed intermittent bolus administration through paravertebral catheters provides lower pain scores and reduced local anesthetic consumption compared to continuous infusion. 2
- One study demonstrated lower pain scores at rest and with coughing using programmed intermittent bolus 2
- Programmed intermittent bolus resulted in a larger number of anesthetized dermatomes 2
- Another study failed to demonstrate significant differences in analgesia or opioid consumption between the two methods 2
Catheter Placement Considerations
Paravertebral catheters placed by anesthesiologists provide superior analgesia compared to surgeon-placed intercostal nerve blocks. 2
- Continuous paravertebral block with ropivacaine 2 mg/mL at 10-14 mL/h showed lower pain scores than single-shot intercostal blocks 2
- No significant difference exists between continuous paravertebral versus intercostal nerve blocks when both catheters are placed by surgeons 2
Skin Preparation and Local Infiltration (If Applicable)
Pre-Procedure Local Anesthesia
For needle insertion, use 1% or 2% lidocaine buffered with sodium bicarbonate in a 1:9 or 1:10 ratio and warmed to body temperature to minimize injection pain. 5
- Use a thin needle (25-30G) for skin infiltration 5
- Inject the local anesthetic slowly to minimize pain 5
- Begin with an intradermal wheal, then infiltrate deeper toward the target site 5
- Apply manual pressure during injection to reduce pain 5
Needle Selection for Neuraxial Procedures
Use pencil-point (atraumatic) spinal needles instead of cutting-bevel needles to minimize the risk of post-dural puncture headache. 2
- This recommendation applies if performing spinal anesthesia rather than paravertebral block 2
- Pencil-point needles do not negatively impact success rates 5
Equipment and Safety Requirements
Essential Equipment and Monitoring
Equipment, facilities, and support personnel should be comparable to those available in the main operating suite, with resources immediately available to treat potential complications. 2
- Have equipment ready to manage: failed block, inadequate analgesia, hypotension, respiratory depression, local anesthetic systemic toxicity, pruritus, and vomiting 2
- Resuscitation equipment must be immediately accessible 2
Clinical Context: Paravertebral Block Indications
Primary Indication: Thoracic Surgery
Paravertebral blocks are most extensively studied and recommended for video-assisted thoracoscopic surgery (VATS) and thoracic procedures. 2
- Multiple studies demonstrate efficacy for postoperative analgesia following thoracic surgery 2
- Paravertebral blocks reduce opioid consumption compared to systemic analgesia alone 2
Limited Evidence for Chronic Pelvic Pain
Paraspinal anesthetic block with 1% lidocaine showed only small, transient pain reduction immediately after injection with no sustained benefit at one week for chronic pelvic pain. 1
- Mean pain scores decreased from 5.50 at baseline to 2.72 within 15 minutes (p=0.03), but returned to 4.36 at one week 1
- This technique involved injection along the spinal process in the supra- and interspinal ligaments using a 25G × 2" needle 1
- Further studies with different dosing regimens are needed to determine efficacy for visceral pain 1
Common Pitfalls and How to Avoid Them
Technical Errors
- Avoid using cutting-bevel needles for neuraxial procedures - always use pencil-point needles to reduce post-dural puncture headache risk 2
- Do not rush local anesthetic injection - slow injection significantly reduces pain 5
- Avoid unbuffered lidocaine - buffering with sodium bicarbonate (1:9 or 1:10 ratio) substantially reduces injection pain 5
Clinical Decision Errors
- Do not assume multiple-level injections are superior - single-injection technique provides equivalent analgesia with less patient discomfort and procedure time 2
- Do not rely on paraspinal blocks for sustained chronic pain relief - evidence shows only transient benefit for chronic pelvic pain 1
- Do not use continuous infusion without considering programmed intermittent bolus - the latter may provide superior analgesia with less local anesthetic 2