[Infusion of morphine and ketamine, with or without lidocaine, in cats undergoing ovariohysterectomy]

ABSTRACT The aim of this study was to evaluate the trans-operative analgesics, continuous infusion of morphine and ketamine, with or without lidocaine in cats undergoing elective OSH. Sixteen adult cats were used, otherwise healthy, pre-medicated with acepromazine (0.1mg/kg) and morphine (0.5mg/kg), both intramuscularly, induced with ketamine (1mg/kg) and propofol (4mg/kg), intravenous, maintained under general inhalation anesthesia with isoflurane 1.4 V%. The animals were randomly allocated into two groups: morphine, lidocaine and ketamine (MLK, n= 8), which received intravenous bolus of lidocaine (1mg/kg) followed by infusion of morphine, lidocaine and ketamine (0.26mg / kg/h, 3mg / kg/h and 0.6mg / kg/h, respectively); Morphine and ketamine (MK, n= 8), who received bolus of saline followed by infusion of morphine and ketamine at the same doses of MLK. The evaluated moments were: M0, basal, 5 minutes after induction; M1 immediately after the application of lidocaine bolus injection or saline; M2, M3, M4 and M5, every 5 minutes to complete 20 minutes after the start of infusion; M6, after the incision of the musculature; M7, after clamping of the first ovarian pedicle; M8, after clamping of the second ovarian pedicle; M9, after clamping of the cervix; M10, after suturing of the musculature; M11, at the end of surgery; And M12, M13 and M14, 5 minute intervals until completing one hour of infusion. The time to extubating and full recovery of animals, and the need for rescue analgesic fentanyl intraoperatively were also evaluated. HR in M0 was higher in MLK when compared to MK. In both groups the SBP was higher in M7 and M8 compared to M0, but the MK, addition of SAP, HR was greater M7 to M13, as well as f. MK animals required a greater number of trans-operative rescues than the MLK. It was concluded that the addition of lidocaine to the protocol using morphine and ketamine increased its analgesia.

摘要 本研究旨在评估针对接受择期卵巢子宫摘除术（Ovariohysterectomy, OSH）的家猫，采用含利多卡因与不含利多卡因的吗啡联合氯胺酮持续输注方案的术中镇痛效果。本研究选用16只健康成年家猫，术前经肌肉注射给予乙酰丙嗪（acepromazine，0.1mg/kg）与吗啡（morphine，0.5mg/kg）进行术前给药；采用氯胺酮（ketamine，1mg/kg）与丙泊酚（propofol，4mg/kg）静脉注射实施麻醉诱导；以1.4%异氟烷（isoflurane）吸入维持全身麻醉。将受试动物随机分为两组：①利多卡因-吗啡-氯胺酮组（MLK，n=8）：先静脉推注利多卡因（1mg/kg），随后持续输注吗啡、利多卡因与氯胺酮，给药速率分别为0.26mg/kg/h、3mg/kg/h与0.6mg/kg/h；②吗啡-氯胺酮组（MK，n=8）：先静脉推注生理盐水，随后以与MLK组相同的剂量持续输注吗啡与氯胺酮。本研究的观测时点设置如下：M0为基础时点，即麻醉诱导后5分钟；M1为利多卡因推注或生理盐水注射结束即刻；M2、M3、M4、M5为输注开始后每5分钟的时点，覆盖输注后20分钟；M6为肌肉层切开即刻；M7为首次卵巢蒂钳夹完成即刻；M8为第二次卵巢蒂钳夹完成即刻；M9为子宫颈钳夹完成即刻；M10为肌肉层缝合完成即刻；M11为手术结束时点；M12、M13、M14为输注开始后每5分钟的时点，覆盖输注后1小时。同时记录受试动物的拔管时间、完全苏醒时间，以及术中需使用补救性镇痛药物芬太尼（fentanyl）的情况。数据分析结果显示：MLK组在M0时点的心率（Heart Rate, HR）高于MK组；两组在M7与M8时点的收缩压（Systolic Blood Pressure, SBP）均高于M0时点，但MK组在M7至M13时点的心率及呼吸频率均高于MLK组；且MK组术中需要补救性镇痛的次数多于MLK组。本研究结论为，在吗啡联合氯胺酮的镇痛方案中加入利多卡因，可提升其镇痛效果。