Erector spinae plane block (ESPB) is a new evolving fascial pain block in the era of regional anaesthesia. ESPB was applied in varieties of surgeries and provided an eminent role in trauma patient especially those with fracture ribs. ESPB exhibits simple, safe and easy technique with minimal or no sympathetic blockade effects, thus gaining popularity in wide range of surgeries. The optimum effective dose of local anaesthetic, the effective volume of drug used for desired dermatomes. Comparison with different regional blocks is preferable to know the optimum analgesic technique for those population of patients (4). Many studies have already compared solo ESPB with thoracic epidural analgesia (TEA), thoracic paravertebral block (TPVB), serratus anterior plane block (SAPB) and pectoral nerves block. Only few case reports described the combination effect of rhomboid intercostal, transversus thoracic muscle and parasternal plane blocks to ESPB in modified radical mastectomy.

patients scheduled for modified radical mastectomy and axillary dissection under general anesthesia (GA) will be included in the study. The patients will be randomly allocated by a computer-generated table into one of the two study groups.Thoracic paravertebral block group (TPV group) and combined erector spinae and pecto-intercostal fascial plane blocks group (ES-PI group).

0.25% bupivacaine and 1 mg dexamethasone will be injected with different volumes in each block.

The first time to ask for rescue analgesia post-operatively will be measured. Using MedCalc Software version 14 (MedCalc Software bvba, Ostend, Belgium), 24 patients (12 patients per group) were calculated for a relative difference of 10% (0.635 hours) in the time to first analgesic request between both groups, with a study power of 95% and an alpha error of 0.05. This number will be increased to 30 patients (15 patients per group) to compensate for possible dropouts.

Analysis of data will be performed using the Statistical Package for Social Science (SPSS) software, version 21 for Microsoft Windows (SPSS Inc., Chicago, iL, USA). Categorical data will be reported as numbers and percentages and will be analyzed using the chi-squared test. Continuous data will be checked for normality using the Kolmogorov-Smirnov test. Normally distributed data will be presented as means (standard deviations) and will be analyzed using the unpaired student t-test. Skewed data will be expressed as medians(quartiles) and will be analyzed using the Mann Whitney U test. For repeated measures, a two-way repeated measures ANOVA will be used to evaluate block (between-groups factor) and time (repeated measures)". Post-hoc pairwise comparison will be performed using the Bonferroni test. A P value of 0.05 or less will be considered significant.

Inclusion Criteria:

• • 18-60 years of age

  • ASA I-II
  • Elective unilateral modified radical mastectomy with axillary lymph node dissection
  • Body weight (50-90 kg)

Exclusion Criteria:

• • Patient refusal

  • Known allergy to any of the study drugs
  • Bleeding disorders (platelets < 50 000, PC <60%, INR>1.5)
  • Infection at the site of needle puncture or sepsis
  • Obesity (BMI > 30 kg/m2)
  • Chronic opioid user eg; morphine addict
  • Chronic pain disease eg certain cancer patients, rheumatological disease
  • Inability to comprehend or use the numeric rating pain scoring system
  • Psychiatric illness eg, psychiatric patients on hypnotic treatment

randomization table created by a researcher who is not involved in the study. The researcher will assign the random ID to each patient and a blinded anesthesiologist will use this ID while collecting the postoperative data in the surgical ward. The block interventions of this study will be done by the same anesthesiologist (well trained to use US-guided regional techniques) while pre-operative and postoperative data collection will be done by another anesthesiologist blinded to the study.