This study evaluates the effect of preoperative carbohydrate loading on early postoperative recovery in patients with type 2 diabetes mellitus undergoing elective abdominal surgery. Traditionally, patients fast before surgery, which can increase insulin resistance, delay recovery, and worsen postoperative outcomes. Preoperative carbohydrate drinks may reduce surgical stress and improve recovery, but concerns exist regarding blood glucose control and gastric emptying in diabetic patients.

In this randomized, double-blind clinical trial, 120 eligible patients will be assigned to three groups: nondiabetic control, nondiabetic with carbohydrate load, and diabetic with carbohydrate load. Patients will receive either a carbohydrate-rich drink or control solution before surgery. Preoperative gastric residual volume will be measured using ultrasound to assess aspiration risk. Blood glucose levels will be measured before and after carbohydrate intake. Postoperative outcomes including metabolic and inflammatory response, nausea and vomiting, length of hospital stay, and time to independent ambulation will be recorded.

The study aims to determine whether preoperative carbohydrate loading is safe and beneficial for diabetic patients undergoing elective abdominal surgery.

This prospective randomized controlled double-blinded study will be conducted at Tanta University Hospitals from June 2024 to June 2025. A total of 120 adult patients (aged 21-65 years, ASA I-II) undergoing elective abdominal surgery will be enrolled. Patients will be randomly assigned to one of three groups: nondiabetic control, nondiabetic carbohydrate load, or diabetic carbohydrate load.

The primary outcome is preoperative gastric residual volume measured by ultrasound. Secondary outcomes include postoperative metabolic and inflammatory response, perioperative blood glucose levels, incidence of nausea and vomiting, length of hospital stay, and time to independent ambulation.

Patients will receive a standardized preoperative meal of yogurt and honey at midnight, with either a clear carbohydrate drink or water administered two hours before anesthesia induction. Gastric ultrasound will be performed pre-induction to assess aspiration risk. Standard general anesthesia protocols will be used, and all patients will be monitored perioperatively.

Ethical approval has been obtained, and informed consent will be collected from all participants. Data confidentiality and patient privacy will be strictly maintained.

Inclusion Criteria:

Adults aged 21-65 years

Both males and females

American Society of Anesthesiologists (ASA) physical status I-II

Scheduled for elective abdominal surgery under general anesthesia

Able and willing to provide informed consent

Exclusion Criteria:

Patient refusal

Known liver or renal pathology affecting gastric function

Mental dysfunction or cognitive disorders impairing consent or cooperation

Increased risk of gastric content aspiration

Body mass index (BMI) < 20 or > 35 kg/m²

Prior upper gastrointestinal surgery

Use of medications affecting gastric motility

Type 1 diabetes mellitus

Type 2 diabetes mellitus treated with insulin

Patients with clinical evidence of diabetic gastropathy or autonomic dysfunction

De-identified individual participant data, including demographic, laboratory, and outcome measures, will be made available to qualified researchers upon reasonable request. Data will be shared through secure institutional channels after publication of the primary results. A data use agreement will be required to ensure participant confidentiality.

De-identified individual participant data and supporting documents will be available beginning 6 months after publication of the primary results, and will remain available for 3 years thereafter.

Data will be accessible to qualified researchers for academic and scientific purposes. Requests must include a research proposal and a signed data use agreement to ensure confidentiality. Access will be provided through secure institutional channels upon approval of the request. Shared data will include de-identified participant-level data, the study protocol, statistical analysis plan, informed consent form, and analytic code.