Respiration rate, heart rate, and body temperature values in cynomolgus monkeys (Macaca fascicularis) during barbiturate anesthesia

Respiration rate, heart rate, and body temperature values were obtained from 14 cynomolgus monkeys (Macaca fascicularis) during neurosurgery under barbiturate anesthesia. Vital sign values markedly declined below baseline during the early stages of surgery, steadily increased as surgery progressed and neared completion, and finally returned to baseline by the end of the postsurgical recovery period. There was considerable variability among the 14 monkeys, but the ranking of each monkey relative to the others remained constant across the period of observation. The findings suggested that the cynomolgus monkey may be more sensitive to barbiturates than the rhesus monkey, and cynomolgus monkeys may exhibit considerable individual differences in their sensitivity to barbiturates.     

Multimodal analgesia protocol for pain management after total knee arthroplasty: comparison of three different regional analgesic techniques

Objectives:To evaluate three different analgesic techniques, continuous epidural analgesia (EA), continuous intra-articular (IA) infusion analgesia and continuous femoral nerve block (FNB) in postoperative pain management, length of hospital stay (LOS), and time of patient mobilization after total knee arthroplasty (TKA).Methods:Seventy-two patients undergoing TKA were randomly allocated into three groups according to the analgesic technique used for postoperative pain management. Group EA patients received epidural analgesia (control group), group IA received intra-articular infusion and group FNB received femoral nerve block.Results:Upon analyzing the Numerical Rating Scale (NRS) scores at rest, at passive and active movement, up to 3 days postoperatively, we observed no statistically significant differences at any time point among the three groups. Similarly, no association among these analgesic techniques (EA, IA, FNB) was revealed regarding LOS. However, significant differences emerged concerning the time of mobilization. Patients who received IA achieved earlier mobilization compared to FNB and EA.Conclusions:Both IA and FNB generate similar analgesic effect with EA for postoperative pain management after TKA. However, IA appears to be significantly more effective in early mobilization compared to EA and FNB. Finally, no clinically important differences could be detected regarding LOS among the techniques studied.     

A COMPARISON OF SOME CYCLOHEXAMINE BASED DRUG COMBINATIONS FOR CHEMICAL RESTRAINT OF SOUTHERN ELEPHANT SEALS (MIROUNGA LEONINA)

This study compared the effects of drug combinations commonly used for chemical restraint of southern elephant seals. The combinations were: ketamine and diazepam, ketamine and midazolam, ketamine and xylazine, and tiletamine and zolazepam. The main aims were to gather basic information regarding the response of the animals to the different combinations, and to determine which were most useful for routine chemical restraint. All drug combinations could be used safely although apnea and whole-body shaking occurred with each. There were significant differences in several of the responses measured. Poor muscle relaxation and prolonged apnea were associated with ketamine and diazepam use. Animals given ketamine and xylatine were more depressed, took longer to recover, had a higher incidence of thermoregulatory problems, and lower heart rate than after other combinations. Ketamine and midazolam and tiletamine and zolazepam produced fewer complications than the other drug combinations, and tiletamine and zolazepam showed greater predictability of response and ease of use, making it preferable for use by people with little experience in anesthesia of elephant seals.     

CO2 anesthesia on Drosophila survival in aging research

Carbon dioxide (CO₂) exposure is a common method of anesthesia in studies of Drosophila melanogaster. A number of negative side effects of CO₂ anesthesia have been reported. It is not clear whether the length of CO₂ anesthesia time affects Drosophila survival in aging research. Here, we examined the potential effect of the CO₂ anesthesia time length of 10–150 min. We found that long CO₂ exposure could lead to Drosophila death, more significant in males. The longer the anesthesia time is, the longer it takes for flies to wake up. Long-time CO₂ anesthesia can reduce the lifespan. Our stress tests showed that long-time CO₂ anesthesia can increase the average survival time in both males and females under starvation conditions, but can only increase female lifespan under H₂O₂ oxidative stress. Long-time CO₂ anesthesia also significantly affects physiological traits, with spontaneous activity increased in females but decreased in males, and reduced female fecundity. Our study suggests that limiting the CO₂ anesthesia time and giving enough recovery time before performing physiological tests are important in Drosophila aging research.     

七氟烷全身麻醉对失血性休克复苏小鼠血流动力学及记忆功能的影响机制

摘要 目的：探讨七氟烷全身麻醉对失血性休克复苏小鼠血流动力学及记忆功能的影响机制。方法：将建立成功的42只失血性休克复苏小鼠按照随机数字表法平分为3组-模型组、氧气组、七氟烷组，对照组吸入空气4 h，氧气组吸入100.0 %氧气4 h，七氟烷组吸入100.0 %氧气和2.5 %七氟烷4 h，监测与记录小鼠血流动力学及记忆功能变化情况。结果：氧气组、七氟烷组麻醉后第3 d与第7 d的Morris水迷宫逃避潜伏期少于模型组，穿越原平台次数多于模型组(P<0.05)，氧气组与七氟烷组对比差异有统计学意义(P<0.05)。氧气组、七氟烷组麻醉后第3 d与第7 d的去甲肾上腺素(Norepinephrine，NE)pD₂与Emax值高于模型组(P<0.05)，七氟烷组高于氧气组(P<0.05)。氧气组、七氟烷组麻醉后第3 d与第7 d的脑组织凋亡指数低于模型组(P<0.05)，七氟烷组低于氧气组(P<0.05)。氧气组、七氟烷组麻醉后第3 d与第7 d的海马组织Akt、Caspase-3蛋白相对表达水平低于模型组(P<0.05)，七氟烷组低于氧气组(P<0.05)。结论：七氟烷全身麻醉在失血性休克复苏小鼠的应用能抑制Akt、Caspase-3蛋白的表达，可抑制脑组织神经细胞凋亡，可改善血流动力学状况，促进小鼠记忆能力的恢复。     

Amnesia,Anesthesia, and Warranted Fear

Is a painful experience less bad for you if you will not remember it? Do you have less reason to fear it? These questions bear on how we think about medical procedures and surgeries that use an anesthesia regimen that leaves patients conscious – and potentially in pain – but results in complete ‘drug‐induced amnesia’ after the fact. I argue that drug‐induced amnesia does not render a painful medical procedure a less fitting object of fear, and thus the prospect of amnesia does not give patients a reason not to fear it. I expose three mistakes in reasoning that might explain our tendency to view pain or discomfort as less fearful in virtue of expected amnesia: a mistaken view of personal identity; a mistaken view of the target of anticipation; and a mistaken method of incorporating past evidence into calculations about future experiences. Ultimately my argument has implications for whether particular procedures are justified and how medical professionals should speak with anxious patients about the prospect of drug‐induced amnesia.     

Anesthetic and pathological changes following high doses of ketamine and xylazine in Sprague Dawley rats

The main objective of this study was to compare the effects of ketamine and xylazine in aging rats when coadministered intraperitoneally at high anesthetic doses. Three groups (n=6 rats/group) consisting of rats at 3, 6 and 12 months of age were used. During anesthesia, animals were monitored for heart rate, respiratory frequency, blood oxygen saturation, and rectal temperature. The corneal and paw withdrawal reflex were also examined during anesthesia. During anesthesia, withdrawal and corneal reflexes were absent for progressively longer durations with increasing age. Significant decreases in cardiac and respiratory frequency and, blood oxygen saturation occurred for the 6- and 12-month-old animals. Respiratory frequency and blood oxygen saturation returned to normal at the end of the anesthesia; however, the significant decrease in cardiac frequency persisted in the 6- and 12-month-old animals. Rectal temperature was decreased significantly only in the 3-month-old animals. Pulmonary edema and effusion occurred in 50% of the 12-month-old animals. In conclusion, if ketamine-xylazine are used for anesthesia, the doses should be optimized for the age of the subjects prior to initiation of the research project.