Analgesic Efficacy of Erector Spinae Plane Block vs External Oblique Intercostal Plane Block in Subcostal Cancer Surgeries

Inclusion Criteria:

* Age (18-65) Years.
* Both sexes.
* Body mass index (BMI): (20-40) kg/m2.
* American Society of Anesthesiology (ASA) physical status II, III.
* Type of surgery; unilateral subcostal incision in hepatectomy and nephrectomy.

Exclusion Criteria:

* Patient refusal.
* Subcostal incisions that are crossing the midline or midline incision.
* Age \<18 years or \>65 years
* BMI \<20 kg/m2 and \>40 kg/m2
* Known sensitivity or contraindication to drugs used in the study
* Contraindication to regional anesthesia e.g. local infection at the site of introduction, pre-existing peripheral neuropathies, and coagulopathy.
* Pregnancy.
* Physical status ASA IV
* patients on chronic analgesic therapy (daily morphine ≥30 mg or equivalent dose of other opioids or tramadol or any medication for neuropathic pain)
* patients with a history of drug abuse
* patients with neuropsychiatric diseases; patients with a history of chronic pain syndromes that may enhance sensitivity to pain, for example, fibromyalgia
* All patients who are going to have severe intra- or post-operative bleeding or will require postoperative mechanical ventilation are also excluded from the study.