CONTINUOUS INTRACISTERNAL AND HIGH CERVICAL INTRATHECAL BUPIVACAINE ANALGESIA IN REFRACTORY HEAD AND NECK PAIN

Background: The upper cervical component of the spino-mesencephalic tr act and cranial nerves V, VII (nervus intermedius), IX, and X are invo lved in mechanisms of acute and chronic pain from head and neck struct ures, To date there is no reliable method for relief of refractory pai n (i.e,, pain that cannot be relieved by conventional pharmacologic th erapies) from these structures. Therefore, we explored continuous intr acisternal infusion of bupivacaine for the treatment of refractory pai n of the head and neck, Methods: Intracisternal catheters were inserte d in 13 adults with refractory nonmalignant (n = 4) and malignant (n = 9) pain from the head, face, mouth, neck, and upper extremities; 0.5% plain bupivacaine was infused continuously at rates of 1-7 (median 1. 5) mg/h with optional bolus doses of 0.5-2.0 mg 4-2 times/h, The effic acy was assessed from pain relief (daily VAS(max), VAS(min), and VAS(m ean) scores 0-10), daily doses of intracisternal bupivacaine and total opioid (expressed as mg parenteral morphine-eq), amount of nocturnal sleep, and rates of adverse effects, Results: The 13 patients were tre ated for 3-182 days (median 37, total 712 days), 3 patients being trea ted at home for 10-112 days (median 88, total 210 days). In one patien t, the efficacy of the treatment could not be estimated because of adv anced senility, Eleven of the remaining 12 patients obtained acceptabl e pain relief with daily doses of intracisternal bu. pivacaine ranging from 20 to 118 mg (median 37 mg): VAS(mean) scores decreased from 7 t o 2, mean pain relief increased from 30% to 80%, total opioid daily do se decreased from 53 to 36 mg parenteral morphine-eq, and nocturnal sl eep increased from 2 to > 6 h (all figures are median values), Speech, eating, walking, and natural functions were generally not affected. S ide effects such as tiredness and malaise, somnolence and sleep, feeli ng of coldness in the neck and skull base, transient post-spinal punct ure headache, paresthesias, hoarseness, dysphagia, transient paresis o f the upper/lower extremities, episodic miosis and conjunctival hypere mia, and transient orthostatic arterial hypotension were each observed in one or two patients, No patient presented clinical evidence of phr enic nerve paralysis, There was no nausea or vomiting, No persistent n eurologic deficit or death could be attributed to the intracisternal p ain treatment, Conclusions: Continuous intracisternal infusion of bupi vacaine may be a useful method in exceptional, well selected patients with refractory pain from the head and neck structures, Further studie s are necessary to establish the indications and the safety of the met hod.