Annales françaises d'anesthèsie et de rèanimation
-
Ann Fr Anesth Reanim · Jan 1990
[Intrathecal and epidural administration of alpha adrenergic receptor agonists].
Alpha-agonists are frequently added to local anaesthetic agents to prolong the duration of spinal or extradural anaesthesia. Adrenaline and phenylephrine have been employed most commonly for this purpose. Recent controlled studies indicated that the alpha-adrenoceptor agonist clonidine, when administered spinally, has a dose-dependent antinociceptive effect. ⋯ However, spinally administered alpha-agonists have side effects, which include vasoconstriction in the spinal cord, hypotension, bradycardia or tachycardia, somnolence and respiratory depression. To minimize such complications, great care may be needed, which is described in this review, assessing the minimal required amount of alpha-agonists and effective clinical monitoring. The development of this technique in the management of subarachnoid and extradural anaesthesia and of chronic pain is discussed.