Intraoperative Infusion of Either Lidocaine or Dexmedetomidine on Regional Cerebral Oxygen Saturation and Postoperative Delirium in Elderly Patients Undergoing Abdominal Surgeries

Tanta University

Status: Enrolling

Conditions: Abdominal Surgeries; Dexmedetomidine; Lidocaine; Cerebral Oxygen Saturation; Intraoperative Infusion; Elderly Patients; Postoperative Delirium

Treatments: Drug: Lidocaine; Drug: Dexmedetomidine

Study type: Interventional

Funder types: Other

Identifiers

NCT07108764

36265MD399/4/25

Details and patient eligibility

About

This study aims to compare the effect of intraoperative infusion of either lidocaine or dexmedetomidine on the incidence of postoperative delirium (POD) in elderly patients undergoing major surgeries. It also aims to evaluate the impact of both medications on intraoperative regional cerebral oxygen saturation (rSO₂).

Full description

Postoperative delirium (POD) is a significant complication in elderly patients undergoing major surgery, with an incidence ranging from 10% to 50%, depending on patient and surgical factors.

Regional cerebral oxygen saturation (rSO₂), measured using near-infrared spectroscopy (NIRS), provides a real-time, non-invasive marker of cerebral perfusion. Previous studies have demonstrated that intraoperative declines in rSO₂ are associated with an increased risk of POD.

Lidocaine, an amide local anesthetic, has been shown to reduce neuroinflammation, improve microcirculation, and exert neuroprotective effects. It has been associated with low postoperative pain, reduced opioid consumption, and improved cognitive outcomes.

Dexmedetomidine, an α2-adrenergic agonist, is known for its sedative, analgesic, and sympatholytic effects. It has been shown to enhance cerebral perfusion, improve rSO₂, and reduce POD incidence.

Enrollment: 100 estimated patients

Sex: All

Ages: 65+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Age ≥ 65years old.
• Both sexes.
• Physical status classification of II - III according to the American Society of Anesthesiologists (ASA).
• Undergo elective non-cardiac surgeries.

Exclusion criteria

• History of mental illness, neurological illness, or scoring less than 8 using the abbreviated mental test (AMT) before operation.
• Severe hearing or visual impairment that may interfere with communication.
• Severe renal or hepatic dysfunction.
• Patients on central nervous system (CNS) medications (antipsychotics, anticonvulsants, antiparkinsonian, antidepressants).
• Contraindications to lidocaine or dexmedetomidine [e.g., allergy, severe bradycardia, atrioventricular (AV) block].

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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100 participants in 2 patient groups

Lidocaine group

Experimental group

Description:

Patients will receive an IV bolus (50 ml) of lidocaine (1mg/kg) diluted with saline over 10 min before induction of anesthesia. This will be followed by intraoperative lidocaine infusion in a dose of 1.5mg /kg/hr till the end of surgery.

Treatment:

Drug: Lidocaine

Dexmedetomidine group

Experimental group

Description:

Patients will receive an IV bolus (50 ml) of dexmedetomidine in dose 0.5 μg/kg over 10 min before induction of anesthesia. This will be followed by intraoperative dexmedetomidine infusion in a dose of 0.3 μg/kg/hr till the end of surgery.

Treatment:

Drug: Dexmedetomidine