Comparison Between Serratus Anterior Plane Block, and Transversus Thoracic Plane Block Combined With Serratus Anterior Plane Block, for the Management of Post-mastecomy Pain.

Breast cancer is one of the most common cancers in women all over the world. In the united states, according to the CDC "Center of Disease Control", it's the second most common cancer occurring in women. Perioperative pain after breast surgeries remains to be taken lightly due to the minimal invasiveness of breast surgeries. However, it is estimated that 25-60% of patients undergoing breast cancer related surgeries develop chronic pain. Acute post-operative pain remains an important risk factor in developing chronic post-mastectomy pain; about 40% of women will have acute post-operative pain, on the other hand, 50% will have chronic pain. Different regional anaesthesia techniques have achieved better management of post-breast surgery acute pain and subsequently less frequent chronic pain. Add to that, effective regional anaesthesia will decrease both the surgical stress response and the requirements of general anaesthetics and opioids, which will keep the function of the immune system intact. A lot of regional anaesthesia techniques have been used to control anterior chest wall pain as the pectoral nerves (PECs) block, paravertebral block, intercostal nerve blocks, thoracic epidural analgesia, serratus anterior plane block. The breast receives its innervation through the anterior and lateral cutaneous branches of the 2nd to the 6th intercostal nerves. Targeting the serratus plane is a safer and a simpler procedure than multiple intercostal or paravertebral blocks. As a setback for the serratus anterior plane block, it only blocks the lateral cutaneous branches of the intercostal nerves with minimal if any effect on the anterior cutaneous branches. The serratus anterior plane block, being unable to block the anterior cutaneous branches of the intercostal nerves, have to be combined with another technique, transversus thoracic plane block, which can block them. The investigators here are trying to measure the efficacy of the combined serratus anterior plane block and tranversus thoracic plane block on the management of post-mastectomy pain.