The goal of this clinical trial is to compare the clinical effects of using Ringer's Lactate and Sterofundin/ Plasmalyte as maintenance fluids in adult patients who have undergone abdominal surgery and are septic.

The primary outcome will be the change in serum lactate levels. Secondary outcomes will include renal function parameters, qSOFA scores, and the incidence of postoperative complications within the first 72 hours following surgery.

The goal of this clinical trial is to compare the clinical effects of using Ringer's Lactate and Sterofundin/PlasmaLyte as maintenance fluids in adult patients who have undergone abdominal surgery and are septic.

The primary outcome will be the change in serum lactate levels. Secondary outcomes will include renal function parameters, qSOFA scores, and the incidence of postoperative complications within the first 72 hours following surgery.

The main questions it aims to answer are:

1. Does the choice of fluid produce different outcomes in this patient population?
2. If yes, then which fluid produces better outcomes?

Enrolled patients will be randomly assigned Ringer's Lactate or Sterofundin for intravenous infusion. The volume, infusion rate and additive content will be determined by the treating clinicians. The intervention will last for 72 hours after patients' enrolment.

Inclusion Criteria:

• Underwent Abdominal Surgery and postoperative length of stay is more than 24 hours
• ASA 1 to 4
• Diagnosis of sepsis (qSOFA score 2 or more)

Exclusion Criteria:

• Patients with Renal failure/hepatic failure/severe metabolic acidosis
• Patients requiring renal replacement therapy prior to enrolment
• Patients with suspected poisoning
• Pregnant women
• Patients having solitary kidney