The aim of the planned study is to assess the prophylactic effect of intraoperative administration of a single dose of methylprednisolone 2 (mg/kg) in decreasing the incidence of postoperative acute kidney injury after cardiac surgeries with cardiopulmonary bypass.

Patients undergoing any type of elective cardiac surgical procedure requiring CPB will be randomly assigned into one of the following groups

1. Placebo group / Control group will receives normal saline as a placebo after the induction of anesthesia and before initiating CPB.
2. Methylprednisolone group / Interventional group receives a single intra-venous dose of methylprednisolone (2 mg/kg) after the induction of anesthesia, and before the initiation of CPB.

Measurements:

Primary outcome:

Incidence of occurrence of postoperative acute kidney injury for 7 days according to the RIFLE criteria.

Secondary outcome:

1. Incidence of postoperatively hyperglycemia (blood glucose level of ≥ 140 mg/dl) for 7 days,
2. Duration of ICU stay,
3. Length of hospital stay (LOS),
4. Incidence of wound infection,
5. Incidence of peptic ulcer,
6. Incidence of sepsis.

Inclusion Criteria:

1. Age 18-65 years.
2. Sex: Both sexes.
3. Patients with American Society of Anesthesiologists (ASA) score III-IV.
4. Patients scheduled for any kind of elective cardiac surgical procedure requiring cardiopulmonary bypass (e.g., coronary artery bypass grafting (CABG), valve repair/replacement, or combined procedures (

Exclusion Criteria:

1. Declining to give written informed consent.
2. History of allergy to the medications used in the study.
3. Diabetic patients with HbA1C >6.5
4. Moderate to severe hepatic diseases (Child B-C)
5. Hepatic dysfunction: INR > 1.5, serum albumin < 2.9 g%.
6. Renal dysfunction (serum Creatinine level >1.3 mg/dl, or GFR < 80 ml/min./1.73/m2
7. Patients with a recent history of AKI.
8. Patients undergoing urgent cardiac surgery.
9. Patients undergoing cardiac surgeries with deep hypothermic total circulatory arrest.
10. Planned off-pump procedure.
11. Any cardiac surgery exceeds 45 minutes on Aortic cross clamp.
12. Patients requiring high doses of inotropes and/or vasopressors intraoperative or postoperative (high-dose dopamine is defined as peak doses of >15 μg/kg/min, high-dose norepinephrine is defined as peak dose >0.1 μg/kg/min, high-dose epinephrine is defined as peak dose >0.1 μg/kg/min)
13. Delayed extubation for more than 6 hours postoperative.
14. Patients developed postoperative complications as (septic shock and bleeding)