Neuraxial Dexmedetomidine-Help or Hype?
- 1. Neuraxial Dexmedetomidine-Help or Hype?
Abstract
Neuraxial dexmedetomidine, high selective alpha-2 adrenergic agonist has gained attention as adjuvant in neuraxial anesthesia. Dexmedetomidine enhances sensory and motor block quality, prolongs postoperative analgesia, and offers stable hemodynamic profiles with fewer side effects like respiratory depression or pruritus compared to opioids. It is associated with dose-dependent risks: bradycardia and hypotension. Although promising, dexmedetomidine’s widespread adoption in neuraxial anesthesia is tempered by the need for robust data for long-term safety and optimal dosing
INTRODUCTION
Neuraxial anesthesia encompasses epidural and spinal techniques, is a critical modality for providing analgesia in surgical and obstetric settings [1]. Traditionally, local anesthetics and opioids have been utilized to achieve effective blocks [2]. Optimizing block duration and reducing side effects like hypotension, motor blockade, and respiratory depression remain clinical challenges [3]. Dexmedetomidine, a maximum selective alpha-2 adrenergic agonist, gained attention for its utility in neuraxial anesthesia. Unlike traditional agents, dexmedetomidine induces sedation, analgesia, and anxiolysis without significant respiratory depression, making it suitable for neuraxial administration [4] Dexmedetomidine enhances sensory and motor blockade quality and prolongs its duration when used in neuraxial blocks. This effect is mediated through its action on alpha-2 receptors in the spinal cord’s dorsal horn inhibiting nociceptive transmission and reducing substance P release [5]. Research demonstrated if used as an adjuvant, neuraxial dexmedetomidine reduces required dose of local anesthetics while providing superior hemodynamic stability and extended postoperative analgesia [6,7]. Determining optimal dosing remains a debated subject but average recommended dose ranges from 3μg to 10μg, balancing efficacy against potential adverse effects such as bradycardia and hypotension [8,9]. Unlike opioids, dexmedetomidine has a lower incidence of pruritus and urinary retention. Despite this, widespread adoption of dexmedetomidine in neuraxial anesthesia still being explored. We need more data on long-term outcomes, neurotoxicity, and patient-specific responses. We aim to evaluate current evidence regarding the efficacy, safety, and mechanisms underlying neuraxial dexmedetomidine [10]