Dexmedetomidine as an adjuvant to analgesic strategy during vaso-occlusive episodes in adolescents with sickle cell disease

Sickle cell disease (SCD)-patients experience recurrent vaso-occlusive episodes (VOE), which are associated with severe pain. While opioids are the mainstay of analgesic therapy, in some SCD patients, increasing opioid use is associated with continued and increasing pain. Recently, dexmedetomidine, a specific α2-adrenoreceptor agonist with sedative and analgesic properties, has been used clinically and shown to reduce opioid requirement and to facilitate opioid withdrawal. We report three patients admitted for severe pain associated with VOEs, who after failing to respond to high-dose opioid and sub-anesthetic dosing of ketamine, were treated with dexmedetomidine. For comparison, we reviewed four additional SCD patients who were admitted for VOEs and treated with opioids and sub-anesthetic doses of ketamine at the same time but had not received dexmedetomidine. In the patients receiving dexmedetomidine, the reasons to initiate infusions included ineffective pain management and the clinical concern for opioid-induced hyperalgesia. Dexmedetomidine infusions doses ranged from 0.2-1μg/kg/h and lasted three to six days. All three patients received transdermal clonidine post-infusion. Dexmedetomidine was associated with marked reduction in daily morphine equivalent intake and decreases in Visual Analog Scale (VAS, 1-10) scores. In the patients receiving dexmedetomidine, the pre-infusion range of morphine equivalent was 2mg-5.75mg/k/d and post infusion ranged from 0-0.87mg/k/d. The VAS ranges pre-infusion were 8-10 and post-infusion 2-6. No adverse effects were identified related to dexmedetomidine including hemodynamic changes requiring vasoactive or anticholinergic agents. We acknowledge the limitations in this report and recognize that in the absence of a control arm and from very few patients we are unable to draw conclusions about safety and efficacy of dexmedetomidine in SCD pain. Thus, given the anecdotal reports of the use of dexmedetomidine in SCD patients with VOEs, including those reported here, dexmedetomidine should be further investigated in SCD patients. Abstract source