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

Not Applicable

Recruiting

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

• Registration Number: NCT07108764
• Lead Sponsor: Tanta University

Brief Summary

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).

Detailed 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.

Study Timeline

• Study Start: 2025-04-17
• Status Verified: 2025-07
• Study First Submitted: 2025-07-31
• Study First Submitted QC: 2025-07-31
• Last Update Submitted: 2025-07-31
• Study First Posted: 2025-08-07
• Last Update Posted: 2025-08-07
• Primary Completion: 2027-04-01
• Study Completion: 2027-04-01

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 100

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].

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Lidocaine group	Lidocaine	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.
Dexmedetomidine group	Dexmedetomidine	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.

Primary Outcome Measures

Name	Time	Method
Incidence of postoperative delirium	Three days after surgery	Incidence of postoperative delirium (POD) will be recorded.

Secondary Outcome Measures

Name	Time	Method
Degree of pain	24 hours postoperatively	Postoperative numerical rate scale (NRS) score will be recorded on admission to the post-anesthesia care unit (PACU), at six h, 12h, and 24h postoperatively.
Mean arterial blood pressure	Till end of surgery (Up to 2 hours)	Mean arterial blood pressure will be recorded at baseline, after induction, after 15 min, then every 15 min till the end of surgery.
Regional cerebral oxygen saturation	Till end of surgery (Up to 2 hours)	Regional cerebral oxygen saturation (rScO2) will be recorded using cerebral oximetry at the baseline, 5 min after induction of general anesthesia, then every 20 min till the end of surgery.
Postoperative opioid consumption	24 hours postoperatively	Rescue analgesia in the from 3 mg IV morphine (mg) will be given if the numerical rate scale (NRS) is ≥ 4 repeated with 10 10-minute lock-out interval till the NRS becomes less than 3.
Incidence of adverse effects	24 hours postoperatively	Incidence of adverse effects such as nausea, vomiting, and respiratory depression will be recorded.
Heart rate	Till end of surgery (Up to 2 hours)	Heart rate will be recorded at baseline, after induction, after 15 min, then every 15 min till the end of surgery.

Trial Locations

Locations (1)

Tanta University; 🇪🇬 Tanta, El-Gharbia, Egypt