Erector Spinae Block Versus Paravertebral Block on Chronic Pain After Mastectomy

The Effect of Erector Spinae Block Versus Paravertebral Block on the Incidence of Chronic Pain After Mastectomy: A Randomized Controlled Trial

The goal of this clinical trial is to learn if the erector spinae block can reduce the incidence of chronic pain compared to the paravertebral block in adult patients undergoing total mastectomy. The study includes patients aged 18 to 80 years scheduled for mastectomy, with or without axillary dissection. The main questions it aims to answer are:

• Does erector spinae block reduce the incidence of chronic pain at 3 months after mastectomy compared to paravertebral block?
• Does erector spinae block affect postoperative outcomes such as opioid consumption at 48 hours, pain scores (in PACU, 24 and 48 hours), block performance time, and the incidence of complications, anxiety or depression, and pain intensity at 3 months?

Researchers will compare patients receiving erector spinae block to those receiving paravertebral block to determine if erector spinae block provides equivalent or improved outcomes in terms of chronic pain and perioperative measures.

Participants will:

• Be randomly assigned to receive either erector spinae block or paravertebral block prior to surgery
• Undergo total mastectomy (with or without axillary dissection)
• Have their pain assessed in the PACU and at 24 and 48 hours postoperatively
• Have opioid consumption measured during the first 48 hours after surgery
• Be followed up at 3 months to assess chronic pain, pain intensity, and psychological outcomes (anxiety or depression)

Background: Acute post mastectomy pain is a strong predictor of the development of chronic pain. Paravertebral block (PVB) has been shown to reduce the incidence and severity of acute and chronic pain post mastectomy. Despite the use of ultrasound, the performance of this advanced block requires special skills and training due to the proximity of the injection site to the pleura and the spinal cord. Erector spinae block (ESB), a novel regional anesthesia technique, has been shown to be equivalent to PVB in reducing the incidence and severity of acute post-surgical pain.

Specific aims: The primary objective of this study is to compare the effect of ESB and PVB on the incidence of chronic pain measured 3 months after mastectomy. Secondary objectives include assessment of cumulative opioid consumption at 48 hours post operatively, pain scores in the PACU as well as at 24 and 48 hours, time needed for performing the block, as well as complications, anxiety or depression at 3 months, pain intensity at 3 months. Methods: This prospective randomized clinical trial will be conducted in the operating rooms at AUBMC. 132 (66 in each group) adult patients scheduled to total mastectomy, with or without axillary dissection, and aging between 18 and 80 will be randomly allocated to 2 groups: The erector spinae group or the paravertebral group. Significance: It has not been demonstrated yet that the ESB is equivalent to the more conventional PVB in reducing the incidence of chronic post mastectomy pain. This study will compare the effect of ESB to PVB in reducing the incidence of chronic pain, which will improve the quality of life of patients undergoing modified radical mastectomy

Inclusion Criteria:

• Adult patients between 18 and 80 years old.
• Scheduled to total mastectomy with or without axillary dissection
• Willing to receive regional anesthesia in addition to GA
• ASA classification 1-3

Exclusion Criteria:

• Previous thoracic surgery with an incision of >2 cm
• Patient's refusal
• Allergy to local anesthetics
• Pregnant women
• Any contraindications to thoracic PVB, including intrathoracic infection, infection at the puncture site, cancer invasion of the puncture site, severe spinal deformity, history of spinal surgery, and severe coagulopathy; anticoagulants intake.
• American Society of Anesthesiologists (ASA) classification of 4 or higher,
• History of chronic pain or untreated clinical severe depression