Paravertebral Block for Thoracic Surgery.

UNLABELLED

Local anesthetic injected into a wedge-shaped space lateral to the spinal nerves as they emerge from the intervertebral foramina produces somatosensory and sympathetic nerve blockade effective for anesthesia and for managing pain of unilateral origin from the chest and abdomen. Paravertebral blockade (PVB) is versatile and may be applied unilaterally or bilaterally. Unlike thoracic epidural, the PVB technique may be used to avoid contralateral sympathectomy, thereby minimizing hypotension and leading to better preservation of blood pressure. There are no reports on systemic toxicity associated with bilateral PVB despite the need for relatively large doses of local anesthetics. This review includes an important historic background and captures the resurgence of PVB-an almost lost technique. Thoracic PVB provides post-thoracotomy pain relief comparable with thoracic epidural analgesia (TEA) with lower side effects supported by moderate-quality evidence. The feasibility and potential of bilateral thoracic PVB for bilateral thoracic surgery appear practical. However, there is existing controversy in the assumption that thoracic PVB is a satisfactory, safer alternative when anticoagulation status is a contraindication to thoracic epidural placement. During the last 2 decades of systematic reviews and meta-analyses, both TEA and PVB have been deemed appropriate in the management of thoracic surgery. A multimodal approach to analgesia includes regional techniques for thoracic surgery that may reduce the likelihood of the development of postoperative complications and chronic pain.

PURPOSE OF THIS REVIEW

The authors evaluated current opinion, clinical practice, new multimodal adjuvants, regional anesthesia, and innovation and technology related PVB in the thoracic surgery patient population. The review focuses on history, techniques, application, ease of placement, and relative safety of this regional technique. For this review, studies and reference lists were retrieved from the Cochrane library, Embase, and Medline from January 1995 through January 2017.

SUMMARY

Existing evidence demonstrates noninferiority of thoracic PVB compared with TEA for postoperative analgesia, with fewer side effects for unilateral and bilateral thoracic surgery, including video-assisted thoracoscopy. The determining factors in selecting the regional technique of choice include the following: (1) tolerance of side effects associated with TEA, (2) consensus on best practice or technique, and (3) operator experience. There is no consensus on the optimal approach for thoracic PVB technique or any standardization when comparing the landmark, ultrasound-guided, or stimulation-based PVB approaches. Moreover, the efficacy of TEA compared with PVB in preventing post-thoracotomy chronic pain syndrome has not been investigated thoroughly and requires future clinical trials.