Comparative Study Between Dexmedetomidine and Fentanyl as Adjuvants to Bupivacaine

Combined femoral and sciatic nerve block provides surgical anesthesia with better cardiorespiratory stability as compared to the spinal anesthesia blockade which has side effects of hypotension, bradycardia, meningitis, post dural puncture headache, hematoma, and neurological deficit, Adjuvants are those drugs which, when co-administered with local anesthetic agents, may improve the speed of onset and duration of analgesia and counteract disadvantageous effects of local anesthetics. By adding these adjuvants, the dose of local anesthetics like bupivacaine can be reduced, thereby reducing its side effects like myocardial depression, hypotension, bradycardia, heart block, and ventricular arrhythmias. Based on "Combination Wisdom", the use of adjuvants to local anesthetics has been promoted a lot .A wide variety of drugs have been used for both neuraxial and peripheral nerve blocks, and the most commonly used drug as adjuvant is the fentanyl .

The addition of dexmedetomidine during US-guided combined femoral and sciatic block for below knee surgery was associated with a prolonged duration of analgesia.

Inclusion criteria

• Patients aged 18-65 years.
• American Society of Anesthesiologists (ASA) physical status I-II,
• Scheduled for elective surgery below the knee.

Exclusion criteria

• Allergies to used medications.
• Coagulopathy.
• Septic patients.
• Neurological disease.
• Respiratory or cardiac disease.
• Diabetes mellitus.
• Patients' refusal to participate.