Chrubasik S, Chrubasik J, Pfisterer M, Hage R, Schulte-Mönting J
Department of Internal Medicine I, University of Heidelberg Hospital, Germany.
Reg Anesth. 1996 May-Jun;21(3):175-81.
The study compared bolus injection of fentanyl versus morphine to supplement epidural infusion of morphine for pain relief after major abdominal surgery.
Postoperative epidural analgesia was activated by patient request for pain relief. Thirty patients were given a loading dose (random assignment, double-blind administration) of 2 mg of morphine (group M, n = 15) or 60 micrograms of fentanyl (group F/M, n = 15), along with an epidural infusion of 0.2 mg/h of morphine. Additional boluses of 0.5 mg of morphine (group M) or 25 micrograms of fentanyl (group F/M) were given according to individual need. If patients were painfree for 3 hours, the infusion rate for morphine was reduced by 50%.
Both treatments provided similar degrees of analgesia, although onset time was shorter for the F/M group (P < .05). To obtain 24 hours of analgesia, group M needed 18.0 mg of morphine, while group F/M needed 4.7 mg of morphine and 1.48 mg of fentanyl. For group M, mean serum concentrations of morphine decreased from 18 ng/mL at 1 hour from the start of treatment to 5 ng/mL at 24 hours. For group F/M, serum morphine stayed at approximately 4 ng/mL, but serum fentanyl increased from 0.28 ng/mL at 5 minutes to about 0.8 ng/mL at 16 hours.
When fentanyl is added continuously to epidural morphine, the resulting higher total serum levels of opioids during prolonged treatment may increase the risk of respiratory depression. Combining the two opioids for the loading dose, however, may be valuable to shorten the onset time of analgesia.
本研究比较了大剂量注射芬太尼与吗啡，以补充硬膜外输注吗啡用于腹部大手术后的镇痛。
术后硬膜外镇痛通过患者要求缓解疼痛来启动。30例患者接受负荷剂量（随机分组，双盲给药），其中15例给予2mg吗啡（M组），15例给予60μg芬太尼（F/M组），同时硬膜外输注0.2mg/h的吗啡。根据个体需要额外给予0.5mg吗啡（M组）或25μg芬太尼（F/M组）。如果患者3小时无痛，则将吗啡输注速率降低50%。
两种治疗方法提供的镇痛程度相似，尽管F/M组的起效时间较短（P<.05）。为获得24小时镇痛，M组需要18.0mg吗啡，而F/M组需要4.7mg吗啡和1.48mg芬太尼。对于M组，吗啡的平均血清浓度从治疗开始后1小时的18ng/mL降至24小时的5ng/mL。对于F/M组，血清吗啡维持在约4ng/mL，但血清芬太尼从5分钟时的0.28ng/mL增加到第16小时时的约0.8ng/mL。
当芬太尼持续加入硬膜外吗啡时，在长期治疗期间产生的较高的总血清阿片类药物水平可能会增加呼吸抑制的风险。然而，将两种阿片类药物联合用于负荷剂量可能有助于缩短镇痛起效时间。
