Effectiveness of Serratus Anterior Muscle Plane Block With Thoracic Paravertebral Block For Unilateral Mastectomies

RESEARCH STRATEGY

1. Background

Breast cancer is a potentially deadly disease affecting one in eight women. [1] Majority of them undergo mastectomies along with different modalities of treatment like chemotherapy, radiotherapy and hormonal treatments.

Since mastectomy is the main and most commonly preferred treatment for breast cancer surgery, it raises the focus on the most frequently studied complication that is persistent pain following surgery [8, 9] The incidence of pain syndrome six months post-breast cancer surgical treatment was 52.9%.[7] A multivariate analysis of the presence of chronic pain in breast cancer survivors revealed risk factors including more invasive surgery, radiation therapy after surgery, and clinically meaningful acute postoperative pain. Each risk factor independently predicted more intense chronic pain at three months after surgery. [8] A 20% prevalence rate of the Post Mastectomy Pain syndrome was found. Women experiencing the syndrome reported chronic, stable pain of long duration that began shortly after surgery. [10] The syndrome is important to recognize because of how debilitating the pain can be. Studies have indicated that post mastectomy pain interferes with activities of daily living like driving, taking care of the children, leisure time, and sex, all of which result in poor quality of life. It was also noted that in women who survived treatment of breast cancer, chronic pain often caused mood changes, difficulty at work, and reduction of physical activities. This was especially noted in those women whose pain spreads to other areas of the body. [14]

There are various anesthetic techniques available for management of mastectomies. The effectiveness of each technique is widely studied regarding pain control, requirement of rescue analgesia, side effects, post-operative hospital stay and development of persistent pain following breast cancer surgical treatment. Belzarena SD et al compared the effectiveness of thoracic epidural block and general anesthesia for oncologic mastectomy. Patients were divided in two groups in which they either received GA or thoracic epidural anesthesia as primary anesthetic. [10] The results showed that the quality of postoperative analgesia was better in the epidural group, which also presented with lower consumption of analgesics. The length hospitalization in this group was also lower. They concluded that an epidural block had some advantages when compared with general anesthesia and can be considered an anesthesia option in oncologic mastectomies with axillary lymph node dissection.