Cardio-pulmonary and Analgesic Effects of Pre-peritoneal VS Epidural Infusion of L-bupivacaine on Abd. Cancer Patients

Inclusion Criteria: * Patients subjected to major upper abdominal cancer surgery. * The enrolled age will be from 18 years to 70 years * ASA, I-III and NYHA, I-III. Exclusion Criteria: * ASA physical status and NYHA \>III, * pregnant women, * body mass index \>40 kg/m2, * preoperative opioid consumption, * Contraindications or patient's refusal of epidural analgesia, and inability to use a PCA device. * Contraindications of use of spirometry device : A) Cerebral aneurysm, Recent brain surgery, recent concussion, recent eye surgery\& Significant glaucoma. B) Recent sinus surgery or middle ear surgery or infection. C) Pneumothorax, Significant aortic aneurysm, Recent thoracic surgery or Recent abdominal surgery . D) Systemic hypotension or severe hypertension (eg, \>200/120 mmHg), Significant atrial/ ventricular arrhythmia , Noncompensated heart failure , Recent myocardial infarction or pulmonary embolus. E) History of syncope related to forced exhalation/cough. F) Active tuberculosis , Hemoptysis or oral bleeding . 7-Uncooperative patients regarding use of spirometry \[Inability to follow directions (eg, confusion, dementia, young age, language barrier)\].