全凭静脉麻醉下不同麻醉深度对下腹部剖腹手术患者术后痛觉过敏的影响

Effects of different depth of total intravenous anesthesia on postoperative hyperalgesia in patients undergoing lower abdominal operation

目的通过观察全凭静脉麻醉下行下腹部剖腹手术患者术后痛觉过敏发生情况,研究不同麻醉深度对下腹部剖腹手术后痛觉过敏的影响。方法选择40例妇科择期行下腹部剖腹手术患者按照麻醉深度不同分为B1组(维持BIS 40~49)和B2组(BIS 50~59),每组20例。两组均采用全凭静脉气管插管全麻。测量患者触痛阈及机械痛觉过敏范围的基础值;记录两组患者术中静脉麻醉药用量、清醒时间及拔管时间;记录患者入室后(T_0)、探查腹腔时(T_1)、手术结束时(T_2)、拔管后1h(T_3)、4h(T_4)、12h(T_5)、24h(T_6)、48h(T_7)的MAP、HR;记录T_3~T_7的VAS评分;记录术后第1天及第2天镇痛泵具体用药量、追加PCA次数等情况;采用纤毛机械刺激针(Von Frey Hairs)测定术后T_6和T_7的触痛阈及机械痛觉过敏范围。结果 B1组T6、T7时MAP明显低于,T_2、T_4时HR明显慢于B2组(P<0.05)。T_6和T_7时B1组切口下部触痛阈明显低于,切口上、下部机械痛觉过敏范围明显长于T_0时(P<0.05);T_6和T7时B2组切口上、中、下部触痛阈明显低于,机械痛觉过敏范围明显长于T_0时,但T_7时切口上、中、下部触痛阈明显高于T_6时(P<0.05)。T_7时B1组切口上、中、下点机械痛觉过敏范围明显短于B2组(P<0.05)。结论全凭静脉麻醉中维持患者的BIS值在40~49的状态可以减轻术后机体的应激反应,减轻术后痛觉过敏的发生,且术后48h机械痛觉过敏范围的恢复较快。

Objective By observing the incidence of postoperative hyperalgesia in patients with total intravenous anesthesia,to study the effects of different anesthesia depth on postoperative hyperalgesia.Methods Forty gynecologic patients undergoing open lower abdominal operation were randomized into two groups （n=20）： group B1 with BIS 40-49 and the group B2 with BIS 50-59.Anaesthesia was induced and maintained with intravenous anesthetics.The threshold of haphalgesia and the range of mechanical hyperalgesia were measured before operation.The consumption of the intravenous anesthetics,the emergence time and the extubation time were recorded.The vital signs were recorded at eight time points： pre-aneasthesia （T0）,abdominal exploration （T1）,the end of operation （T2）and 1 h （T3）,4 h （T4）,12 h （T5）,24 h （T6）,48 h （T7） after extubation.The VAS scores at T3-T7 were recorded.The PCA dosage of analgesic and superaddition in postoperative 24 h and 48 h were recored.The Von Frey Hairs were used to assessed the threshold of haphalgesia and the range of mechanical hyperalgesia at T6 and T7.Results The MAP at T6 and T7 and the VAS scores at T6 of the group B1 were lower than those of the group B2 （P〈0.05）.The range of mechanical hyperalgesia at T7 of the group B1 was narrower than that of the group B2 （P〈0.05）.Conclusion Maintaining the anesthesia depth within BIS 40-49 can reduce the body′s stress reaction,decrease the incidence of postoperative hyperalgesia and accelerate the recovery time of mechanical hyperalgesia in postoperative 48 h.