Our adult regional and acute pain service is staffed by seven rotating faculty out of over fifty total anesthesiology faculty, with two senior residents rotating each month. Ultrasound is used on all peripheral nerve blocks. Strong resident interest, along with a desire to improve our service with additional techniques, prompted the development of a paravertebral block service.
Development and Implementation
A single surgeon was recruited for the project. Beverly Talbert, MD was willing to allow paravertebral catheters in patients undergoing mastectomy and breast tissue expansion procedures. The surgeon was using a field block of liposomal bupivacaine for pain control at this time, but was concerned about its off-label use.
Initially, anesthesiology personnel were limited to two faculty and two fourth-year residents. As there was limited faculty experience with paravertebral techniques, a literature review was conducted, anatomy reviewed, and expert opinion sought out through connections established by our device representative.
We elected for a longitudinal needle and ultrasound approach, as this technique appeared to have a superior safety and success profile.(Image 1A) Needle visualization was difficult as noted in the literature with unreliable loss of resistance after puncture of costotransverse ligament. Hydrodissection was utilized as a more dependable indicator of needle tip location and was critical to our success.
1% lidocaine was used for hydrodisscetion as normal saline was uncomfortable, even with sedation. Important paravertebral anatomy included the costotransverse ligament, transverse process, and pleura.(Image 2A) It was found that larger dissecting boluses obscured visualization, but small, quick bursts allowed for identification of needle position with less anatomical distortion. Once through the costotransverse ligament, injection of long acting local anesthetic depressed the pleura without upward or superficial displacement of tissue above the ligament, verifying appropriate needle placement in the paravertebral space.(Image 2B)
After the space was expanded with Tuohy in the space a catheter was advanced into the space and secured.(Image1B) A continuous infusion pump filled with 0.25% lidocaine was utilized post-operatively. Follow-up was performed in-person for inpatients and by phone for outpatients at least once daily while the catheter an infusion remained active.
As technical skill improved, practical and clinical parameters were established, and more regional team members were recruited. Careful attention was paid to proper technique as it evolved with the experience of the team.
Standardizing our technique to minimize variability, and continuously evaluating our experiences and outcomes has been crucial to the ongoing success of this block technique. The evolution has been based on literature review, team feedback, and overall consensus. Once the initial group refined the necessary skills and understanding of reliably performing the block the remaining faculty were trained and implementation of the service was a very smooth process. Having a relatively small group of regional faculty likely helped to maintain consistency while quickly implementing this service.
We feel that the success of our project was multifactorial. Having an enthusiastic surgeon allowed us to refine our skills with a steady flow of appropriately selected patients. Early patient satisfaction reaffirmed the surgeon’s belief in our project and provided the confidence to offer the technique to other surgical providers.
After a 100% success rate with over thirty blocks during a one month period, the service was offered to additional surgeons. Newly incorporated surgical teams included trauma, cardiothoracics, plastics, and urology. These services have begun to request and benefit from this block technique and find their patients more comfortable and satisfied. We will continue developing this technique, incorporating alternative approaches, and providing it to the services and patients that may benefit.