local and regional anesthesia have been introduced with the goal of reducing the side effects associated with general anesthesia and IV opioid analgesia.our hypothesis is that ultrasound-guided interscalene brachial plexus block and erector spinae plane block will provide efficient surgical anesthesia and postoperative analgesia after modified radical mastectomy.

inadequate analgesia after modified radical mastectomy with axillary lymph node dissection may occur with most of regional anesthesia. pain in the axilla and upper limb is related to ineffective block of medial and lateral pectoral nerves as long thoracic and thoracodorsal nerves, leading to inadequate analgesia.The aim of this study is to evaluate the efficacy and safety of ultrasound-guided interscalene brachial plexus block and erector spinae plane block for providing surgical anesthesia and postoperative analgesia after modified radical mastectomy.

Inclusion Criteria:

• Female patients aged 40-85 years old
• American Society of Anesthesiologists' physical status III and IV
• Planned for modified radical mastectomy with axillary lymph node dissection

Exclusion Criteria:

• Patient refusal
• Neurological or psychiatric disorders
• Local infection at injection site
• Spine or chest wall deformity
• Allergy or any contraindication to any of the study drugs
• Opioid or alcoholic addiction
• Chronic pain of any cause
• Uncooperative patients.

statistics of the age ,BMI, duration of surgery,success rate, time of first analgesic request,patients' and surgeon's satisfaction, and complications

Individual patient data will be shared after finishing and publication of the study.and it will be available for 1 year.

the individual patient data will be available for scientific research only up on email request. request will be sent to email of principal investigator (drmonagh19802000@gmail.com)