Glynn C J, Jamous M A, Teddy P J
Oxford Regional Pain Relief Unit, ICRF Building, Churchill Hospital, Oxford OX3 7LJ UK Department of Neurological Surgery, Radcliffe Infirmary, Oxford OX2 6HE UK Nuffield Department of Anaesthetics, Radcliffe Infirmary, Oxford OX2 6HE UK.
Pain. 1992 Jun;49(3):361-367. doi: 10.1016/0304-3959(92)90243-5.
Ten patients with deafferentation pain after spinal cord injury were given 150 micrograms clonidine epidurally. CSF and plasma samples were collected over the following 24 h, and drug concentrations were measured by radio-immunoassay. The results of only 6 patients are included in the pharmacokinetic analysis because the catheters were not in the epidural space in the remaining 4 patients. These analyses revealed a mean maximum CSF concentration of 228 ng/ml whereas the mean plasma concentration at all time points was less than 0.7 ng/ml. The elimination half-life of epidural clonidine was 66 +/- 2 min, while the absorption half-life was 31 +/- 7 min, Tmax was 60 +/- 7 min and Cmax was 228 +/- 56 ng/ml. The ratio of the area under the curve (AUC) for CSF and plasma was 52. One patient's catheter was intrathecal and 3 were not in the epidural space. The measured plasma concentrations were similar after all injections. As 4 of 6 patients with epidural catheters obtained pain relief and all 3 patients with spasms obtained relief from epidural clonidine, these data suggest that clonidine has a place in the treatment of patients with spinal cord injury.
对10例脊髓损伤后去传入性疼痛患者进行硬膜外注射150微克可乐定。在接下来的24小时内采集脑脊液和血浆样本，并通过放射免疫分析法测定药物浓度。药代动力学分析仅纳入了6例患者的结果，因为其余4例患者的导管未置于硬膜外间隙。这些分析显示，脑脊液平均最大浓度为228纳克/毫升，而所有时间点的血浆平均浓度均低于0.7纳克/毫升。硬膜外可乐定的消除半衰期为66±2分钟，吸收半衰期为31±7分钟，达峰时间为60±7分钟，峰浓度为228±56纳克/毫升。脑脊液与血浆的曲线下面积（AUC）之比为52。1例患者的导管位于鞘内，3例不在硬膜外间隙。所有注射后测得的血浆浓度相似。由于6例置有硬膜外导管的患者中有4例疼痛缓解，3例痉挛患者均从硬膜外可乐定治疗中获得缓解，这些数据表明可乐定在脊髓损伤患者的治疗中占有一席之地。
