Comparision of Different Doses of Dexmedetomidine With Low Dose Bupivacaine in Selective Spinal Anesthesia for Transurethral Resection of Prostate in Elderly Males.

SYNOPSIS:

Comparison of different doses of intra-thecal dexmedetomidine as an additive to low-dose bupivacaine(5mg) in selective spinal anesthesia for transurethral resection of prostate in elderly patients.

Introduction:

Most patients scheduled for Transurethral Resection of the Prostate Gland are elderly and usually present with cardiovascular, endocrine, renal, cerebral or respiratory diseases thereby increasing their risk for surgery and anaesthesia. Spinal anesthesia is the technique of choice in transurethral resection of prostate . The major problem of spinal technique is risk of hypotension. In spinal anesthesia due to sympathetic blockade, there is vasodilatation leading to diminished venous return which is the main contributory factor for hypotension. 1 Selective spinal anesthesia , commonly known as saddle block, is defined as "the practice of employing minimal doses of intrathecal agents so that only the nerve roots supplying a specific area and only the modality that require to be anesthetized are affected." Thus, Selective spinal anesthesia is more appropriate in elderly patients3 Saddle block paralyzed pelvic muscles and sacral nerve roots. As lower level of block is achieved, hemodynamic derangement is less and fluid requirement is also less. So there is minimum chance of circulatory overload1 but may provide insufficient surgical anaesthesia.5and also may not achieve an extended duration of postoperative analgesia.2 Dexmedetomidine is a highly selective alpha2 adrenoceptor (α2-AR) agonist recently introduced to anaesthesia practice. It produces dose-dependent sedation, anxiolysis and analgesia (involving spinal and supraspinal sites) without respiratory depression7 intrathecal Dex has been used as an adjuvant to different local anesthetics in humans with various doses ranging from 2.5 to 15 micrograms [2,3,9-15] resulting in improving the quality of sensory and motor blockade and increasing their duration and decreasing the dose of local anesthetic used intrathecal Dex has been used as an adjuvant to different local anesthetics in humans with various doses ranging from 2.5 to 15 micrograms [2,3,9-15] resulting in improving the quality of sensory and motor blockade and increasing their duration and decreasing the dose of local anesthetic used intrathecal Dex has been used as an adjuvant to different local anesthetics in humans with various doses ranging from 2.5 to 15 micrograms, resulting in improving the quality of sensory and motor blockade and increasing their duration and decreasing the dose of local anesthetic used.4

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