Saito Takafumi, Kurashima Akihiko, Oda Tazunu, Aoki Satoshi, Endo Hiroshi, Nashimoto Takeo, Yamada Ryuichi
Department of Neurosurgery, Nagano Red Cross Hospital, 5-22-1 Wakasato, Nagano 380-8582, Japan.
No Shinkei Geka. 2002 Jun;30(6):593-9.
Organ transplantation from brain death patients started in Japan in 1997. However it is difficult to diagnose brain death in patients treated with barbiturate therapy. In this study, the influence of long continuous administration of barbiturate on diagnosis of brain death was investigated by measuring plasma concentration of barbiturate. In 15 patients treated with barbiturate therapy, plasma concentrations of thiamylal were measured by liquid chromatographic apparatus every day until it's level decreased below 0.1 microgram/ml after cessation of continuous administration. At the same time, plasma thiamylal levels were checked on the day when burst-suppression (b-s) pattern had disappeared in 9 cases, light reflex of pupil appeared in 7 cases and spontaneous respiration had been detected by trigger lamp in 11 cases. The plasma concentrations of thiamylal on the day when b-s pattern had disappeared differed clearly among the cases in the range of 8.8 to 37.9 micrograms/ml. Those cases in which light reflex of the pupil had been recognized were also different in the range of 17.8 to 57.8 micrograms/ml. The cases in which spontaneous respiration had been detected were in the range of 4.4 to 23.0 micrograms/ml. These concentrations varied about 4, 3 and 5 times among the cases examined. The intervals between cessation of continuous administration of thiamylal and the decrease of plasma concentration to below 0.1 microgram/ml also varied from 2 to 14 days from case to case. The minimum concentration of thiamylal on the day when b-s pattern had disappeared, light reflex of the pupil had been recognized and spontaneous respiration had been detected was 8.8, 17.8 and 4.4 micrograms/ml respectively. These results suggest that diagnosis of brain death in patients treated with barbiturate therapy is able to be made when the plasma thiamylal level is below 4.4 micrograms/ml.
脑死亡患者的器官移植于1997年在日本开始。然而，对于接受巴比妥酸盐治疗的患者而言，诊断脑死亡存在困难。在本研究中，通过测量巴比妥酸盐的血浆浓度，调查了长期持续给予巴比妥酸盐对脑死亡诊断的影响。在15例接受巴比妥酸盐治疗的患者中，使用液相色谱仪每天测量硫喷妥钠的血浆浓度，直至连续给药停止后其水平降至0.1微克/毫升以下。与此同时，在9例爆发抑制（b-s）模式消失的当天、7例瞳孔光反射出现的当天以及11例通过触发灯检测到自主呼吸的当天，检查血浆硫喷妥钠水平。b-s模式消失当天硫喷妥钠的血浆浓度在8.8至37.9微克/毫升范围内，各病例之间差异明显。瞳孔光反射被识别的病例其浓度范围也在17.8至57.8微克/毫升之间。检测到自主呼吸的病例其浓度范围在4.4至23.0微克/毫升之间。在所检查的病例中，这些浓度分别相差约4倍、3倍和5倍。硫喷妥钠连续给药停止至血浆浓度降至0.1微克/毫升以下的间隔时间也因病例而异，从2天到14天不等。b-s模式消失、瞳孔光反射被识别以及检测到自主呼吸当天硫喷妥钠的最低浓度分别为8.8微克/毫升（b-s模式消失）、17.8微克/毫升（瞳孔光反射被识别）和4.4微克/毫升（检测到自主呼吸）。这些结果表明，当血浆硫喷妥钠水平低于4.4微克/毫升时，能够对接受巴比妥酸盐治疗的患者进行脑死亡诊断。
