Spinal anesthesia has many advantages such as reducing the metabolic stress response to
surgery, reduction in blood loss, decrease in the incidence of venous thromboembolism,
reduction in pulmonary compromise (particularly in patients with advanced pulmonary
disease),return of bowel function rapidly, allow hospital discharge early and the ability to
monitor the patient's mental status, but the limited duration of action is one of its
disadvantages. Intrathecal α2-agonists prolong the duration of action of local anesthetics
and reduce the total required dose.(1, 2) Dexmedetomidine is a centrally acting highly
specific α2 -agonist and its α2/α1 selectivity are 8 times higher than that of clonidine.(3)
It is commonly used as a sedative, preemptive analgesic,(4) to decrease the incidence of
postoperative nausea, vomiting (PONV)(5) and to maintain stable hemodynamics(6). It also has
been used as an additive to local anesthetics in peripheral nerve blocks, brachial plexus
block7, subarachnoid anesthesia and caudal anesthesia (8).
Local anesthetics have been widely used in medical practice to produce anesthesia, analgesia
and for pain management. Nowadays, minor surgical operations have been done under local
anesthesia outside the operating theaters, in this area monitoring and resuscitation
facilities of the case are suboptimal compared to operating rooms. The complications of local
anesthesia are different from localized reactions such as urticaria, edema, and dermatitis to
systemic absorption leading to severe cardiovascular collapse and neurological toxicity. The
incidence of local anesthetics to produce systemic toxicity decreased in the past 30 years,
from 0.2 to 0.01 %.( 9) Recently, patient safety changes a clinician's perspective on
understanding the pharmacology of drug interactions and complications of local anesthetics.
The safety of local anesthetic usage has improved owing to the introduction of newer agents
(eg; Ropivacaine and Levobupivacaine). (10) Levobupivacaine is a long-acting local anesthetic
similar to that of Bupivacaine in a pharmacological structure. Bupivacaine, a widely used
local anesthetic in regional anesthesia presents in a commercial preparation as a racemic
mixture (50:50) of its two enantiomers, Levobupivacaine, S (−) isomer and destroy-
bupivacaine, R (+) isomer.
Levobupivacaine has been shown to have a safer pharmacological profile (11) with less cardiac
and neurotoxic adverse effects. (12) Small doses of dexmedetomidine 5µg used in combination
with Levobupivacaine, in humans for spinal anesthesia has been shown to produce a more rapid
onset of motor block, and a longer duration of motor and sensory block with preserved
hemodynamic stability and lack of sedation2.