右美托咪啶在静脉吸入复合全身麻醉方案中对患者苏醒期应激反应及寒战发生率的影响

目的 研究右美托咪啶在静脉吸入复合全身麻醉方案中对患者苏醒期应激反应及寒战发生率的影响.方法 选取2019年3月至2020年6月于我院进行外科手术并使用静吸复合全身麻醉方案的152例符合标准的患者纳入研究,采用随机数字法将患者分为试验组(76例)与对照组(76例),试验组给予静脉持续泵入右美托咪啶辅助静吸复合全身麻醉方...     

麻醉前加温输液对蛛网膜下腔麻醉患者中心体温及寒战的影响

目的评估麻醉前加温输液对蛛网膜下腔麻醉患者中心体温及寒战的影响。方法ASAⅠ级、择期在蛛网膜下腔麻醉下行下肢骨科手术患者120例,随机分为麻醉前加温输液组(A组)及麻醉前未加温输液组(B组),每组60例。A组患者以输液加温器加温液体,保证整个输液过程液体温度在37.5±0.5℃范围内;B组患者未在蛛网膜下腔麻醉前加温输液,待麻醉完成后开始以37.5±0.5℃温度加温输液。比较两组患者入手术室、麻醉开始前、蛛网膜下腔麻醉后5、10、20、30、45、60、90、120min、术毕的中心体温(肛温),寒战程度、发生率及发生时间。结果(1)A组患者各时间点中心体温相似(F=1.157,P=0.108),B组患者各时间点中心体温差异有统计学意义(F=2.355,P=0.032),其中以蛛网膜下腔麻醉前、蛛网膜下腔麻醉后5、10、20、30min较低;麻醉前、蛛网膜下腔麻醉后5、10、20、30min,A组患者中心体温明显高于B组(t=2.578、2.822、2.173、2.137、2.157;P=0.021、0.009、0.032、0.039、0.036);蛛网膜下腔麻醉后45、60、90、120min及术毕两组患者的中心体温相似;(2)A组有9例(15%)患者出现寒战, B组有29例(48%)患者出现寒战,寒战总发生率A组低于B组(χ²=15.404,P=0.001),其中0~5min期间及5~10min期间A组低于B组(χ²=6.400,P=0.011;χ²=5.217,P=0.022),而10~20min期间两组相似(χ²=3.077,P=0.079)。寒战发生程度1、2、3、4级者A组分别为5、3、1及0例,B组分别为10、8、9及2例。结论与麻醉后加温输液相比,蛛网膜下腔麻醉前加温输液能有效保持患者中心体温,并明显降低蛛网膜下腔麻醉后寒战的发生率。     

术中保温对老年开胸患者生命体征的影响

目的 观察术中保温对老年开胸患者生命体征的影响.方法 将60例行开胸手术老年患者随机分为保温组和对照组,每组30例.保温组患者术中控制室温22～24℃,输入的液体加温至37 ℃,并选用加温至37℃的灌洗液进行胸腔冲洗;对照组患者术中仅控制室温,不采用任何保温措施.测定术前及术后核心体温,比较两组患者围手术期的收缩压、心率、体温变化和寒战发生情况.结果 保温组患者术中体温维持稳定,手术前后体温、收缩压、心率、无明显变化,在人室时、消毒时和手术中1 h及手术结束前差异无统计学意义(P>0.05);对照组患者与术前及保温组比较,术中体温显著下降,收缩压、心率波动明显(P<0.01);而保温组低温(<36℃和<35℃)、寒战发生率显著低于对照组(P<0.01).结论 老年开胸患者术中保温可维持患者体温的稳定,有效预防术中低温和寒战的发生.     

Thermoresponsiveness of posterior hypothalamic (PH) neurons of rats to scrotal and abdominal thermal stimulation

The thermoresponsiveness of posterior hypothalamic (PH) neurons to localized, incremental thermal heating and cooling between 10–40°C of the abdomen or scrotum was determined in urethane anesthetized, male Sprague–Dawley rats whose core temperature was maintained at 37°C during testing. PH extracellular neuronal activity was recorded along with changes in gastrocnemius muscle EMG activity and temperature (T_ms, indicative of shivering thermogenesis) and intrascapular brown adipose tissue temperature (T_IBATs, indicative of non-shivering thermogenesis). Seventy-five PH neurons were recorded following both scrotal and abdominal trials of thermal stimulation. Nine percent of PH neurons were classified as warm responsive neurons (WRNs), 20% as cold responsive (CRNs), and 71% as temperature nonresponsive neurons (TNRNs), based on their thermal coefficients (TCs). Mean TC for warm PH neurons was significantly increased with scrotal warming between 30–40°C from the mean TC of the same PH WRNs following abdominal warming. Similarly, the thermal coefficient was increased (i.e., was more negative) for cold responsive PH neurons to scrotal cooling (20–10°C) as opposed to the TC of the same PH CRNs for abdominal cooling. No shivering thermogenesis (no change in temperature or EMG activity from gastrocnemius muscle) or non-shivering thermogenesis (no significant increase in IBAT temperatures) occurred with scrotal or abdominal cooling in these 21°C acclimatized rats. The results indicate that a small population of PH neurons are thermoresponsive to localized physiological changes in temperature of the scrotum and abdomen with greater thermoresponsiveness shown of both warm and cold PH neurons to scrotal vs. abdominal thermal stimulation.     

剖宫产产妇术中寒战的危险因素

目的 探讨剖宫产产妇术中寒战的危险因素。方法 回顾性分析2018年1月至2021年12月行子宫下段剖宫产术产妇2 808例的临床资料,年龄22～48岁,ASAⅠ或Ⅱ级。收集产妇信息和术中寒战发生情况,并且通过手麻系统中不良事件登记的寒战程度分级(Wrench分级)评估术中寒战的程度。根据Wrench分级评分将产妇分为两组：寒战组(Wrench分级评分≥1分)和非寒战组(Wrench分级评分=0分)。采用单因素和多因素Logistic回归分析筛选剖宫产产妇发生术中寒战的危险因素。结果 发生术中寒战的产妇有673例(23.96%)。单因素分析显示,BMI、手术时间、胎儿剖出时间、手术室温度、补液量、液体丢失量、消毒碘伏温度、术中有无使用加温毯、右美托咪定与剖宫产产妇发生术中寒战有关(P<0.05)。多因素Logistic回归分析显示,BMI(<23.5 kg/m²,OR=1.231,95%CI 1.101～1.376,P=0.026)、手术室温度(<21℃,OR=1.826,95%CI 1.303～2.561,P<0.001)、术中未使用加温毯...     

剖宫产术中产妇寒战与羊水入血关系的探索

目的探讨剖宫产术中寒战与羊水入血的关系,为预防和治疗剖宫产术中寒战提供新的思路。方法采用前瞻性双盲病例对照研究。ASA分级Ⅰ、Ⅱ级产妇57例,全部采用蛛网膜下腔阻滞麻醉,麻醉医师观察产妇术中寒战程度并分级。记录产妇的一般情况(姓名、年龄、身高、体重)、出血量、液体入量、孕龄、新生儿体重、手术时长、新生儿1 min Apgar评分和寒战分级等,测量并记录产妇麻醉前、麻醉后30 min、术终3个时点的肛温。按照Dewitte寒战分级法将产妇分为4组:0级为非寒战组(0组),寒战1~3级分别为1组、2组、3组,其中1、2、3组合称寒战组。所有产妇均于手术结束前抽取静脉血2 ml检测唾液酸Tn(sialyl Tn,sTn)抗原浓度。分别对寒战程度与sTn抗原浓度、孕龄、出血量、液体入量、手术时长、新生儿体重、3个时间点肛温关系进行相关性分析。结果各组产妇年龄、身高、体重、出血量、液体入量、孕龄、新生儿体重、手术时长、3个时间点肛温比较,差异无统计学意义(P>0.05)。2组和3组sTn抗原浓度明显高于0组和1组(P<0.05),1组sTn抗原浓度明显高于0组(P<0.05)。寒战组sTn抗原浓度明显高于非寒战组(P<0.05)。寒战程度和sTn抗原浓度的相关系数为0.895(P<0.01),而孕龄、出血量、液体入量、手术时长、新生儿体重、3个时点肛温与寒战程度并无相关性。结论剖宫产术中产妇寒战与羊水入血相关。     

曲马多、酒石酸布托啡诺与盐酸右美托咪定治疗腰硬联合麻醉剖宫产患者寒战的效果比较

目的观察比较静注曲马多、布托啡诺、右美托咪定对剖宫产腰硬联合麻醉后寒战的治疗效果。方法选择ASAⅡ~Ⅲ级剖宫产腰硬联合麻醉后寒战的子痫前期患者180例,随机分为曲马多、布托啡诺、右美托咪定3组,每组60例。对于发生寒战的患者,待胎儿取出后,分别静注曲马多1.0 mg/kg、布托啡诺0.01 mg/kg或右美托咪定0.5μg/kg,观察寒战改善情况、用药后镇静程度及不良反应发生情况。结果三组治疗寒战的有效率差异无统计学意义(P>0.05)。给药后,曲马多组有9例发生恶心,4例发生呕吐;布托啡诺组有5例发生恶心,无呕吐发生。右美托咪定组有1例发生恶心,无呕吐发生。三组均无呼吸抑制。与曲马多组相比,布托啡诺组、右美托咪定组不良反应发生率均较低(P<0.05)。结论三种药物均可以有效治疗寒战,右美托咪定镇静效果更佳,且不良反应更少。     

曲马多联合昂丹司琼预防剖宫产麻醉后寒颤的效果观察

目的：观察曲马多联合昂丹司琼预防蛛网膜下腔麻醉后寒颤的临床效果。方法将120例行剖宫产的产妇随机分为观察组A、观察组B和对照组。麻醉开始前,观察组A缓慢静脉注射曲马多1mg／kg,观察组B缓慢静脉注射曲马多1mg／kg＋昂丹司琼4mg,对照组给予生理盐水4ml。观察麻醉开始至手术结束4h内产妇寒颤、恶心呕吐、眩晕、低血压、呼吸抑制等不良反应情况和新生儿Apgar评分情况。结果观察组A和观察组B产妇寒颤发生率均低于对照组,差异均有统计学意义（P＜0．05）,观察组A恶心呕吐发生率高于观察组B和对照组,差异均有统计学意义（P＜0．05）,观察组B与对照组恶心呕吐发生率差异无统计学意义（P＞0．05）。3组均未发生眩晕、呼吸抑制等,且术中低血压发生率3组间差异无统计学意义（P＞0．05）,3组新生儿Apgar评分组间差异无统计学意义（P＞0．05）。结论曲马多联合昂丹司琼能有效预防蛛网膜下腔麻醉后的寒颤反应,且恶心呕吐的发生率较低。     

Motion sickness increases the risk of accidental hypothermia

Motion sickness (MS) has been found to increase body-core cooling during immersion in 28°C water, an effect ascribed to attenuation of the cold-induced peripheral vasoconstriction (Mekjavic et al. in J Physiol 535(2):619–623, 2001). The present study tested the hypothesis that a more profound cold stimulus would override the MS effect on peripheral vasoconstriction and hence on the core cooling rate. Eleven healthy subjects underwent two separate head-out immersions in 15°C water. In the control trial (CN), subjects were immersed after baseline measurements. In the MS-trial, subjects were rendered motion sick prior to immersion, by using a rotating chair in combination with a regimen of standardized head movements. During immersion in the MS-trial, subjects were exposed to an optokinetic stimulus (rotating drum). At 5-min intervals subjects rated their temperature perception, thermal comfort and MS discomfort. During immersion mean skin temperature, rectal temperature, the difference in temperature between the non-immersed right forearm and 3rd finger of the right hand (ΔT _ff), oxygen uptake and heart rate were recorded. In the MS-trial, rectal temperature decreased substantially faster (33%, P < 0.01). Also, the ΔT _ff response, an index of peripheral vasomotor tone, as well as the oxygen uptake, indicative of the shivering response, were significantly attenuated (P < 0.01 and P < 0.001, respectively) by MS. Thus, MS may predispose individuals to hypothermia by enhancing heat loss and attenuating heat production. This might have significant implications for survival in maritime accidents.     

Muscle glycogen depletion during exercise at 9‡ C and 21‡ C

Summary This study compared glycogen depletion in active skeletal muscle after light and moderate exercise in both cold and comfortable ambient conditions. Twelve male subjects (Ss) were divided into two groups equally matched for the submaximal exercise intensity corresponding to a blood lactate concentration of 4 mM (W4) during cycle exercise. On two separate days Ss rested for 30 min at ambient temperatures of either 9 C or 21 C, with the order of temperature exposure being counter-balanced among Ss. Following rest a tissue specimen was obtained from the m. vastus lateralis with the needle biopsy technique. Six Ss then exercised on a cycle ergometer for 30 min at 30% W4 (range=50–65 W) while the remaining group exercised at 60% W4 (range=85–120 W). Another biopsy was taken immediately after exercise and both samples were assayed for glycogen content. Identical procedures were repeated for the second environmental exposure. No significant glycogen depletion was observed in the Ss exercising at 30% W4 in 21 C, but a 23% decrease (p=0.04) was observed when the same exercise was performed at 9 C. A 22% decrease (p=0.002) in glycogen occurred in the 60% W4 group at 21 C, which was not significantly different from that observed during the same exercise at 9 C. The results suggest that muscle substrate utilization is increased during light exercise in a cold environment as compared to similar exercise at a comfortable temperature, probably due to shivering thermogenesis. Heat produced with higher exercise intensities seems to be sufficient to prevent shivering and the accompanying glycogenolysis.