Evaluation of the Analgesic Effect of Dexmedetomidine Versus Fentanyl as Adjuvants to Epidural Bupivacaine in Patients Undergoing Lumbar Spine Surgeries

To determine if the epidural route provide an acceptable analgesia in spine surgeries and avoided the need for excessive IV analgesics. Also to determine whatever dexmedetomidine or fentanyl is more better neuroaxial adjuvant regarding providing early onset and prolonged analgesia and stable cardiorespiratory parameters

Relieving post-operative pain of spine surgeries has become an indispensable component in anesthesiology. Various methods have been tried for the management of post-operative pain in spine surgeries out of which regional techniques are becoming most promising. The quality of regional anesthesia has been reported to improve with the addition of opioids (such as morphine, fentanyl, and sufentanil) and other drugs (such as dexmedetomidine, clonidine, magnesium sulfate, neostigmine, ketamine, and midazolam), but no drug to inhibit nociception is without associated adverse effects . α2 adrenergic agonists have both analgesic and sedative properties when used as an adjuvant in regional anesthesia. Dexmedetomidine is an S-enantiomer of medetomidine with a higher specificity for α2-adrenoreceptor (α2 : α1, 1620 : 1) compared to clonidine (α2 : α1, 220 : 1). It was first introduced into practical use as intravenous sedative after the approval of U.S. Food and Drug Administration in 1999. Since then it has been investigated as the anxiolytic, sympatholytic, and analgesic properties related to α2-adrenoceptor binding, and it is now being used as a co-analgesic drug. As adjuvant, neuroaxial administration is the appropriate route to dexmedetomidine, because the analgesic effect of α2-agonists mostly occurs at spinal level, and dexmedetomidin's high lipophilicity facilitates rapid absorption into the cerebrospinal fluid and binding to the spinal cord α2-adrenoreceptor. regional-administeration of dexmedetomidine has been shown to exert potent antinociceptive effects in animals. To date, a few studies have reported on the effects of epidural dexmedetomidine combined with local anesthetics in humans. . Administration of an α2-agonist via an intrathecal or epidural route provides an analgesic effect in postoperative pain without severe sedation. This effect is due to the sparing of supraspinal CNS sites from excessive drug exposure, resulting in robust analgesia without heavy sedation . The adverse effects of dexmedetomidine include hypotension, hypertension, nausea, bradycardia, atrial fibrillation, and hypoxia. Fentanyl is one of the short-acting narcotic analgesics with potent morphine-like action . Neuroaxial administration of lipophilic opioids such as Fentanyl and sufentanyl tends to provide a rapid onset of analgesia. Their rapid clearance from cerebrospinal fluid may limit cephalic spread and the development of certain side effects such as delayed respiratory depression

Eligibility Criteria:
Inclusion Criteria:

1. All male patients between the age group of 18 and 65 years
2. Patients of American Society of Anaesthesiologists (ASA) class I and II.
3. Patients who will undergo lumbar spine surgeries (laminectomy ± discectomy for PIVD (Prolapse of intervertebral disc), will be enrolled for this study

Exclusion Criteria:

1. All Patients below the age of 18 years and above 65 years. Also All female patient are excluded from the study.
2. Other spine surgeries rather than laminectomy, also surgeries on more than two levels.
3. Patients with haematological disease, bleeding or coagulation test abnormalities, psychiatric diseases.

4 .Patiensts with history of drug abuse, allergy to any study medication. . 4 .Patients with cervical and thoracic spine surgeries, tubercular spine , any permanent neurological disorders and vertebral deformeties such as scoliosis and spondylolisthesis.

5. Pregnant and lactating patients .

Withdrawal criteria :

Accidental Dural puncture.