体温保护对剖腹胃癌根治术患者快速康复的影响

目的观察体温保护对剖腹胃癌根治术患者快速康复的影响。方法选择剖腹胃癌根治术患者60例,男39例,女21例,年龄45~76岁,ASAⅠ或Ⅱ级,随机分成升温组和对照组,每组30例。升温组患者入室后给予体温保护,开启升温毯至42℃直至患者离开PACU,暴露皮肤均予以干净敷料覆盖,输注液体(包括复方乳酸钠、羟乙基淀粉及红细胞悬液)和腹腔冲洗液体均加热至40℃,呼吸过滤器安置于气管导管处。对照组患者未给予特殊保温加热措施。手术室温度调节至21~23℃。采用红外线鼓膜耳温计观察并记录两组患者入室时(T_1)、麻醉诱导前(T_2)、术中(T_3)、关腹(T_4)、拔管(T_5)、离开PACU(T_6)时患者的核心温度。观察并记录患者麻醉时间、手术时间、手术室温度、术中出血量、术中输血量、麻醉药物用量、总输液量和腹腔液体冲洗量、拔管时间和住院时间等;记录术后寒战、切口感染的发生情况。结果与T_1时比较,T_2~T_6时两组核心温度均明显降低,且升温组核心温度明显高于对照组(P0.05)。升温组术中出血量、术中输血量明显少于,拔管时间和住院时间明显短于,术后寒战及切口感染的发生率明显低于对照组(P0.05);两组麻醉时间、手术时间、手术室温度、麻醉药物用量、总输液量、腹腔冲洗液量差异无统计学意义。结论多方法联合体温保护措施,能明显降低剖腹胃癌根治术患者围术期低体温的发生,有利于患者术后康复。     

术中保温对预防经尿道前列腺电切术患者低温性寒战效果的观察

目的 观察术中保温对预防经尿道前列腺电切术(TURP)患者低温性寒战的效果.方法 将80例TURP患者随机分为保温组和对照组,每组40例.对照组患者术中不采用任何升温装置,使用室温灌洗液进行膀胱冲洗;保温组患者术中输液使用加温器及充气升温毯加温,选用加温至37℃的灌洗液进行膀胱冲洗,测定术前及术后核心体温,比较2组术中...     

主动体温保护对下肢骨折手术凝血功能及出血的影响

目的分析观察围术期主动体温保护对下肢骨折患者已经激活的凝血功能的影响及出血量的变化。方法纳入80例ASAⅠ~Ⅱ级择期行下肢骨折切开复位术的患者,随机分为主动体温保护组和对照组。体温保护组患者进入手术室时,室温设置为26℃,至手术开始调为22℃。3M充气式保温毯覆盖胸腹部,设置其目标体温38℃,保温毯与患者皮肤间用手术单隔开;静脉输液温度37℃,冲洗液温度37℃。对照组予手术巾单覆盖,室温设置为22℃;不使用保暖毯,室温液体输注及冲洗。分别记录两组患者在进入手术室时(T1)、切皮时(T2)、手术开始后1h(T3)、手术结束后1h(T4)的耳温,并分别抽取2mL静脉血行血栓弹力图测定;记录术中失血量及术后36h引流量以及需输血病例数。结果 a)与体温保护组比较,对照组在手术T4时耳温明显低于主动体温保护组,差异具有统计学意义(P0.05);b)主动体温保护组的出血量和36h引流量均低于对照组(P0.05);c)与体温保护组相比,T3、T4时对照组纤维蛋白形成时间、血凝块生成时间明显延长,T4时对照组的最大振幅明显缩短,差异有统计学意义(P0.05)。结论术中低体温造成下肢骨折患者术中及术后凝血因子活性抑制,血小板功能受限,导致手术失血量和引流量增加,输血概率增加。术中主动体温保护措施对于下肢骨折患者可减少机体热量过度散失,对抗纤溶亢进,减少失血量。     

不同保温方法对脊柱手术患者围术期核心体温和恢复情况的影响

目的比较不同保温方法对脊柱手术患者围手术期核心体温及术后恢复的影响。方法选择行择期全麻脊柱手术患者80例,男45例,女35例,年龄18～80岁,BMI 18～25 kg/m~2,ASAⅠ或Ⅱ级,采用随机数字表法分为四组,静脉输液加温组(FW组);强力空气加温毯加温组(AW组);静脉输液加温+强力空气加温毯组(FA组);入手术室前强力空气加温毯预热30 min,术中静脉输液加温+强力空气加温毯组(PFA组),每组20例。入室前FW组、AW组和FA组不予处理,PFA组于术前等候室采用强力空气加温毯预热30 min。术中FW组输入经血液/液体升温仪加热至41℃的液体直到手术结束。AW组将强力空气加温毯覆盖于患者的下肢部位上方,设定温度为43℃。FA组和PFA组均采用输液加温和强力空气加温毯加温。记录患者在麻醉诱导后、切皮后30 min、切皮后60 min、入PACU 10 min和术后48 h时的核心体温;记录患者术后寒战、恶心呕吐发生情况,患者满意度评分和住院时间。结果切皮后30 min FW组核心体温明显低于PFA组(P0.01);切皮后60 min和入PACU 10 min时FW组核心体温明显低于AW组、FA组和PFA组(P0.001)。FW组术后寒战发生率明显高于AW组、FA组和PFA组(P0.05)。四组患者术后恶心呕吐发生率差异无统计学意义。FW组术后患者满意度评分明显低于AW组、FA组和PFA组(P0.05)。四组患者术后住院时间差异无统计学意义。结论脊柱手术全麻患者围手术期强力空气加温毯保温效果优于输液加温,提高了患者满意度,而强力空气加温毯联合输液加温及预热并没有明显优于单纯使用强力空气加温毯保温。静脉输液加温、强力空气加温毯加温及预热保温方法对患者术后恢复的影响无差异。     

充气式保温毯联合输液加温对全麻食管癌手术苏醒和免疫功能的影响

目的探讨充气式保温毯联合输液加温技术对食管癌手术苏醒和免疫功能的影响。方法择期行食管癌根治术患者50例,随机分为温毯+输液输血加温组(W组)和对照组(C组),每组25例。记录麻醉诱导前(T1)、手术开始2h(T2)、手术结束时(T3)、术后2h(T4)的鼻咽温,及麻醉苏醒时间、术后寒战、术后感染及住院时间;采用流式细胞仪检测T1、T3、术后2d(T5)及5d(T6)外周血T淋巴细胞亚群。结果 C组在T2~T4时的鼻咽温较T1时明显降低(P0.05);W组在T2~T4时的鼻咽温明显高于C组(P0.05);C组患者苏醒时间明显延长、术后寒战发生率明显高于W组(P0.05);与T1时比较,两组T3时CD4+淋巴细胞百分率及CD4+/CD8+均明显下降,CD8+淋巴细胞百分率明显升高(P0.05);在T3时,W组CD4+淋巴细胞百分率及CD4+/CD8+明显高于C组,CD8+淋巴细胞百分率明显低于C组(P0.05)。结论在食管癌根治手术中,采用充气式保温毯联合输液加温技术具有保护患者体温、缩短患者苏醒时间、减少术后寒战的发生,同时有利于保护患者的免疫功能。     

加温输液对乳癌根治术病人出凝血机制的影响

目的 减少病人术中出血。方法 将80例乳癌根治术病人随机分成观察组（加温输液）和对照组（室温输液）各40例。观察组在手术过程中输入加温液体（37－38℃），腹部以下盖保温毯，使肛温保持在36－37℃；对照组输入室温液体（20－21℃），不用保温毯。比较两组术后体温、出血量、输血量及部分凝血项目测定值。结果 观察组与对照组手术终止和手术后2h体温比较，均P＜0.05，差异有显著性意义；术中出血量、输血量比较，均P＜0.01，差异有极显著性意义。术后血小板（PLT）计数、凝血酶原活动度（PT％）及纤维蛋白原含量（FIB）比较，均P＜0.05，差异有显著性意义。结论 加温输液可使病人术中术后的体温维持正常，出血量减少。     

术中加温输液对机器人腹腔镜膀胱癌根治术患者体温和凝血功能的影响

目的探讨术中加温输液对机器人腹腔镜膀胱癌根治术患者体温和凝血功能的影响。方法选取择期行机器人腹腔镜膀胱癌根治术患者60例,年龄18～65岁,ASAⅠ～Ⅲ级,随机分为对照组和加温输液组,每组30例。对照组采用常规保温措施(室温24℃以上、患者身体覆盖棉被、预热腹腔冲洗液、术后采用充气式升温系统复温);加温输液组在常规保温措施的基础上术中持续加温输液,温度设置为41℃。观察患者围术期核心体温(鼻咽温)和PT、APTT、TT、Fib、PLT等凝血指标的变化。结果对照组术中体温进行性下降(最低35℃),除了基础值和术后1 h以外的各时间点体温均低于加温输液组,差异有统计学意义(P0.05);加温输液组术中体温与基础值比较也有下降(P0.05),但均在36℃以上。对照组APTT的延长时间大于加温输液组(P0.05)、TT的缩短时间大于加温输液组(P0.05);PT、Fib、PLT组间比较无统计学差异。结论机器人腹腔镜膀胱癌根治术中采用持续加温输液,可维持患者体温正常,避免低体温引起的凝血功能紊乱。     

两种人工腹水加温方法对肝癌消融术患者术中体温的影响

目的探讨输液加温器对人工腹水的保温效果及其对肝癌消融术患者术中体温、寒战、术后并发症的影响。方法将60例行人工腹水输注、肝癌消融术患者随机分为观察组与对照组各30例,观察组术中使用输液加温器将人工腹水加温至40℃,对照组术中人工腹水使用恒温水箱加温至40℃后输注。比较两组人工腹水温度及患者肛温、寒战发生率。结果对照组人工腹水温度、术中肛温显著低于观察组,寒战发生率显著高于观察组(均P0.05)。结论使用输液加温器加温人工腹水,可以提供恒温液体,维持患者术中正常体温,降低寒战。     

五种保温措施对开腹手术患者体温的影响

目的探讨不同保温措施对开腹手术患者体温的影响,以选择适宜的术中保温措施。方法将90例择期行开腹手术患者随机分为输液输血加温组、身体包裹组、湿敷料加温组、冲洗液加温组、保温毯组及对照组,每组15例。术中均常规加盖棉被,对照组不再采用其他保温措施。输液输血加温组将液体及血液采用适宜的方法加温至37℃再输入体内;身体包裹组将患者的双上肢,双大腿下1/3至足部及肩颈部用棉垫包裹;湿敷料加温组术中湿敷料用37℃温盐水浸湿后使用;冲洗液加温组把冲洗液加温至37℃再用于手术野冲洗;保温毯组术前将电热保温毯温度设定为38.5℃铺于手术床。结果身体包裹组鼻咽温、肛温均有下降但不显著(均P>0.05);保温毯组鼻咽温和肛温手术结束时较入室时升高(均P<0.05);输液输血加温组、冲洗液加温组肛温下降显著(均P<0.05),湿敷料加温组鼻咽温、肛温均显著下降(均P<0.01)。结论开腹手术中,为维持患者的正常体温,提高围术期患者的安全性,首选保温毯保温,次选身体包裹保温。     

保温对全麻唤醒手术患者寒战躁动及术中苏醒的影响

目的探讨保温对术中唤醒全麻手术患者寒颤和躁动发生率、失血量、术中和术后苏醒时间及术后住院时间的影响。方法将70例行术中唤醒全麻手术患者随机分成对照组与观察组各35例。对照组行常规体温处理,即棉被覆盖保暖,输入液体及冲洗液加温;观察组在此基础上加用保温毯。围手术期对患者进行直肠温度监测,对两组寒战、躁动、失血量、术中苏醒时间、术后苏醒时间、拔除喉罩时间及术后住院时间进行记录。结果观察组术中核心体温及低体温、寒战、躁动发生率,失血量、术中苏醒时间及术后住院时间显著低于或短于对照组(P0.05,P0.01)。结论围手术期保温能够降低患者寒战、躁动发生率,减少失血量,缩短术中苏醒和术后住院时间。     

Comparison of two different temperature maintenance strategies during open abdominal surgery: upper body forced-air warming versus whole body water garment

BACKGROUND: A new system has been developed that circulates warm water through a whole body garment worn by the patient during surgery. In this study the authors compared two different strategies for the maintenance of intraoperative normothermia. One strategy used a new water garment warming system that permitted active warming of both the upper and lower extremities and the back. The other strategy used a single (upper body) forced-air warming system. METHODS: In this prospective, randomized study, 53 adult patients were enrolled in one of two intraoperative temperature management groups during open abdominal surgery with general anesthesia. The water-garment group (n = 25) received warming with a body temperature (rectal) set point of 36.8 degrees C. The forced-air-warmer group (n = 28) received routine warming therapy using upper body forced-air warming system (set on high). The ambient temperature in the operating room was maintained constant at approximately 20 degrees C. Rectal, distal esophageal, tympanic, forearm, and fingertip temperatures were recorded perioperatively and during 2 h after surgery. Extubated patients in both groups were assessed postoperatively for shivering, use of additional warming devices, and subjective thermal comfort. RESULTS: The mean rectal and esophageal temperatures at incision, 1 h after incision, at skin closure, and immediately postoperatively were significantly higher (0.4-0.6 degrees C) in the group that received water-garment warming when compared with the group that received upper body forced-air warming. The calculated 95% confidence intervals for the above differences in core temperatures were 0.7-0.1, 0.8-0.2, 0.8-0.2, and 0.9-0.1, retrospectively. In addition, 14 and 7% of patients in the control upper body forced-air group remained hypothermic (< 35.5 degrees C) 1 and 2 h after surgery, respectively. No core temperature less than 35.5 degrees C was observed perioperatively in any of the patients from the water-garment group. A similar frequency of the thermal stress events (shivering, use of additional warming devices, subjective thermal discomfort) was observed after extubation in both groups during the 2 h after surgery. CONCLUSIONS: The investigated water warming system, by virtue of its ability to deliver heat to a greater percentage of the body, results in better maintenance of intraoperative normothermia that does forced-air warming applied only to the upper extremities, as is common practice.     

Comparison of Two Different Temperature Maintenance Strategies during Open Abdominal Surgery: Upper Body Forced-air Warming versus Whole Body Water Garment

Background: A new system has been developed that circulates warm water through a whole body garment worn by the patient during surgery. In this study the authors compared two different strategies for the maintenance of intraoperative normothermia. One strategy used a new water garment warming system that permitted active warming of both the upper and lower extremities and the back. The other strategy used a single (upper body) forced-air warming system.

Methods: In this prospective, randomized study, 53 adult patients were enrolled in one of two intraoperative temperature management groups during open abdominal surgery with general anesthesia. The water-garment group (n = 25) received warming with a body temperature (rectal) set point of 36.8[degrees]C. The forced-air-warmer group (n = 28) received routine warming therapy using upper body forced-air warming system (set on high). The ambient temperature in the operating room was maintained constant at approximately 20[degrees]C. Rectal, distal esophageal, tympanic, forearm, and fingertip temperatures were recorded perioperatively and during 2 h after surgery. Extubated patients in both groups were assessed postoperatively for shivering, use of additional warming devices, and subjective thermal comfort.

Results: The mean rectal and esophageal temperatures at incision, 1 h after incision, at skin closure, and immediately postoperatively were significantly higher (0.4-0.6[degrees]C) in the group that received water-garment warming when compared with the group that received upper body forced-air warming. The calculated 95% confidence intervals for the above differences in core temperatures were 0.7-0.1, 0.8-0.2, 0.8-0.2, and 0.9-0.1, retrospectively. In addition, 14 and 7% of patients in the control upper body forced-air group remained hypothermic (< 35.5[degrees]C) 1 and 2 h after surgery, respectively. No core temperature less than 35.5[degrees]C was observed perioperatively in any of the patients from the water-garment group. A similar frequency of the thermal stress events (shivering, use of additional warming devices, subjective thermal discomfort) was observed after extubation in both groups during the 2 h after surgery.     

Active warming during cesarean delivery.

We tested the hypothesis that 15 min of forced-air prewarming, combined with intraoperative warming, prevents hypothermia and shivering in patients undergoing elective cesarean delivery. We simultaneously tested the hypothesis that maintaining maternal normothermia increases newborn temperature, umbilical vein pH, and Apgar scores. Thirty patients undergoing elective cesarean delivery were randomly assigned to forced-air warming or to passive insulation. Warming started 15 min before the induction of epidural anesthesia. Core temperature was measured at the tympanic membrane, and shivering was graded by visual inspection. Patients evaluated their thermal sensation with visual analog scales. Rectal temperature and umbilical pH were measured in the infants after birth. Results were compared with unpaired, two-tailed Student's t-tests and chi(2) tests. Core temperatures after 2 h of anesthesia were greater in the actively warmed (37.1 degrees C +/- 0.4 degrees C) than in the unwarmed (36.0 degrees C +/- 0.5 degrees C; P < 0.01) patients. Shivering was observed in 2 of 15 warmed and 9 of 15 unwarmed mothers (P < 0.05). Babies of warmed mothers had significantly greater core temperatures (37.1 degrees C +/- 0.5 degrees C vs 36.2 degrees C +/- 0.6 degrees C) and umbilical vein pH (7.32 +/- 0.07 vs 7.24 +/- 0.07). IMPLICATIONS: Perioperative forced-air warming of women undergoing cesarean delivery with epidural anesthesia prevents maternal and fetal hypothermia, reduces maternal shivering, and improves umbilical vein pH.     

Ultra-fast-track anesthesia in off-pump coronary artery bypass grafting: a prospective audit comparing opioid-based anesthesia vs thoracic epiduralbased anesthesia

PURPOSE: To examine the feasibility of immediate extubation after off-pump coronary artery bypass grafting (OPCAB) using opioid based analgesia or high thoracic epidural analgesia (TEA) and compare postoperative analgesia with continuous TEA vs patient-controlled analgesia (PCA). METHODS: One hundred consecutive patients undergoing OPCAB were included in this prospective audit. After induction of anesthesia using fentanyl 2 to 5 microg.kg(-1), propofol 1 to 2 mg.kg(-1) and endotracheal intubation facilitated by rocuronium, anesthesia was maintained using sevoflurane titrated according to bispectral index monitoring. Perioperative analgesia was provided by TEA (n = 63) at the T3/T4 interspace or T4/T5 interspace using bupivacaine 0.125% 8 to 14 mL.hr(-1) and repetitive boluses of bupivacaine 0.25% during surgery. In patients who were fully anticoagulated or refused TEA, perioperative analgesia was achieved by i.v. fentanyl boluses (up to 15 microg.kg(-1)) and remifentanil 0.1 to 0.2 microg.kg(-1).min(-1), followed by morphine PCA after surgery (n = 37). Maintenance of body temperature was achieved by a heated operating room and forced-air warming blankets. RESULTS: Ninety-five patients were extubated within 25 min after surgery (PCA, n = 33; TEA, n = 62). Five patients were not extubated immediately because their core temperature was lower than 35 degrees C. One patient was re-intubated because of agitation (TEA group); one was re-intubated because of severe pain and morphine-induced respiratory depression (PCA group). Pain scores were low after surgery, with pain scores in the TEA group being significantly lower immediately, at six hours, 24 hr and 48 hr after surgery (P < 0.05). CONCLUSION: Immediate extubation is possible after OPCAB using either opioid-based analgesia or TEA. TEA provides significantly lower pain scores after surgery in comparison to morphine PCA.     

The efficacy of carbon-fiber resistive-heating in prevention of core hypothermia during major abdominal surgery

BACKGROUND: Perioperative hypothermia causes numerous severe complications, such as coagulopathy, surgical wound infections, and morbid myocardial outcomes. For prevention of intraoperative hypothermia, an inexpensive, non-disposable carbon fiber resistive warming system has been developed. METHODS: We evaluated the efficacy of resistive-heating, comparing to circulating-water mattress and forced-air warming system. Twenty four patients undergoing elective abdominal surgery were randomly assigned to warming with: 1) a circulating water mattress, 2) a lower-body forced-air system, or 3) a carbon-fiber, resistive-heating blanket. RESULTS: Tympanic membrane temperature in the first two hours of surgery decreased by 1.9 +/- 0.5 degrees C in the water mattress group, 1.0 +/- 0.6 degree C in the forced-air group, 0.8 +/- 0.2 degree C in the resistive-heating group. The decreases in core temperature by the end of surgery were 2.0 +/- 0.8 degrees C in the water mattress group, 0.6 +/- 1.1 degrees C in the forced-air group, and 0.5 +/- 0.4 degree C in the resistive blanket group, respectively. There was no significant difference in the changes of core temperature between the forced-air group and the resistive-heating group. No side effects related to resistive-heating blanket were observed. CONCLUSIONS: Even during major abdominal surgery, carbon-fiber resistive-heating maintains core temperature as effectively as forced air.     

Shortening the discharging time after total hip replacement under combined spinal/epidural anesthesia by actively warming the patient during surgery.

BACKGROUND: To compare passive thermal insulation by reflective blankets with forced-air active warming on the efficacy of normothermia maintenance and time for discharging from the recovery room after combined spinal/epidural anesthesia for total hip arthroplasty. METHODS: DESIGN: Prospective, randomized study. SETTING: Inpatient anesthesia at three University Departments of orthopedic surgery. PATIENTS: 50 ASA physical status I-III patients, who were scheduled for elective total hip arthroplasty. INTERVENTIONS: Patients received combined spinal/epidural anesthesia (CSE) with intrathecal injection of 15 mg of 0.5% hyperbaric bupivacaine. All procedures started 8-10 a.m., and operating room temperature was maintained between 21-23 degrees C, with relative humidity ranging between 40-45%. As warming therapy patients received either passive thermal insulation of the trunk, the two upper limbs and the unoperated lower limb with reflective blankets (group passive, n = 25), or forced-air active warming of the two upper limbs (group active, n = 25). Core temperature was measured before CSE placement (baseline), and then every 30 min until recovery of normothermia. RESULTS: Demographic data, duration of surgery, intraoperative blood losses, and crystalloid infusion were similar in the two groups. Arterial blood pressure decreased in both groups compared with baseline values, while no differences in heart rate were observed during the study. Core temperatures in passive group patients decreased more markedly than in actively warmed patients, with a 1 degree C difference between the two groups at the end of surgery (p < 0.0005). At recovery room entry seven patients in group active (24%) and 16 patients in group passive (64%) showed a core temperature < 36 degrees C (p < 0.01). Achievement of both discharging criteria and normothermia required 32 +/- 18 min in active group and 74 +/- 52 min in passive group (p < 0.0005). CONCLUSIONS: Forced-air cutaneous warming allows the anesthesiologist to maintain normothermia during combined spinal/epidural anesthesia for total hip replacement even if the convective blanket is placed on a relatively small skin surface with reflex vasoconstriction. Maintaining core normothermia decreased the duration of postanesthesia recovery and may, therefore, reduce costs of care.     

Resistive-heating and forced-air warming are comparably effective

Serious adverse outcomes from perioperative hypothermia are well documented. Consequently, intraoperative warming has become routine. We thus evaluated the efficacy of a novel, nondisposable carbon-fiber resistive-heating system. Twenty-four patients undergoing open abdominal surgery lasting approximately 4 h were randomly assigned to warming with 1) a full-length circulating water mattress set at 42 degrees C, 2) a lower-body forced-air cover with the blower set on high, or 3) a three-extremity carbon-fiber resistive-heating blanket set to 42 degrees C. Patients were anesthetized with a combination of continuous epidural and general anesthesia. All fluids were warmed to 37 degrees C, and ambient temperature was kept near 22 degrees C. Core (tympanic membrane) temperature changes among the groups were compared by using factorial analysis of variance and Scheffé F tests; results are presented as means +/- SD. Potential confounding factors did not differ significantly among the groups. In the first 2 h of surgery, core temperature decreased by 1.9 degrees C +/- 0.5 degrees C in the circulating-water group, 1.0 degrees C +/- 0.6 degrees C in the forced-air group, and 0.8 degrees C +/- 0.2 degrees C in the resistive-heating group. At the end of surgery, the decreases were 2.0 degrees C +/- 0.8 degrees C in the circulating-water group, 0.6 degrees C +/- 1.0 degrees C in the forced-air group, and 0.5 degrees C +/- 0.4 degrees C in the resistive-heating group. Core temperature decreases were significantly greater in the circulating-water group at all times after 150 elapsed minutes; however, temperature changes in the forced-air and resistive-heating groups never differed significantly. Even during major abdominal surgery, resistive heating maintains core temperature as effectively as forced air. IMPLICATIONS: Efficacy was similar for forced-air and resistive heating, and both maintained intraoperative core temperature far better than circulating-water mattresses. We thus conclude that even during major abdominal surgery, resistive heating maintains core temperature as effectively as forced air.     

Physostigmine Prevents Postanesthetic Shivering As Does Meperidine or Clonidine

Background: Postanesthetic shivering develops in as many as one half of patients recovering from isoflurane anesthesia. Cholinergic stimulation of the hypothalamic-pituitary-adrenal axis and adrenal medulla by physostigmine enhances secretion of arginine vasopressin, epinephrine, and norepinephrine. Because the hypothalamus is the dominant thermoregulatory controller in mammals, and these neurotransmitters may be involved in body temperature control, physostigmine administration may influence the incidence of shivering. Accordingly, the authors tested the hypothesis that physostigmine administration inhibits postanesthetic shivering. Its efficacy was compared with that of saline (negative control) and meperidine and clonidine (positive controls).

Methods: Sixty patients having surgery of the ear or nose were tested. General anesthesia was induced with 2 mg/kg propofol, 0.1 mg/kg vecuronium, and 1.5 micro gram/kg fentanyl and maintained with isoflurane (1.5 +/- 0.4%) in 70% nitrous oxide. At the end of surgery, the patients were randomly assigned to receive an intravenous bolus of 0.04 mg/kg physostigmine, isotonic saline, 0.5 mg/kg meperidine, or 1.5 micro gram/kg clonidine. Heart rate, mean arterial blood pressure, oxygen saturation, visual analog pain score, temperature, and postanesthetic shivering were measured during recovery.

Results: Postanesthetic shivering occurred in 6 of 15 (40%) patients given saline. In contrast, postanesthetic shivering was significantly reduced in physostigmine-treated patients (1 of 15, or 7%) and was absent in patients given clonidine or meperidine.     

Effects of sympathetic blockade on the efficiency of forced-air warming during combined spinal-epidural anesthesia for total hip arthroplasty.

STUDY OBJECTIVE: To evaluate if active cutaneous warming of the two upper limbs with reflex vasoconstriction is less effective in maintaining intraoperative normothermia than warming the vasodilated unoperated lower limb during combined spinal-epidural anesthesia (CSE). DESIGN: Prospective, randomized study. SETTING: Inpatient anesthesia at university departments of orthopedic surgery. PATIENTS: 48 ASA physical status I, II, and III patients, who were scheduled for elective total hip arthroplasty. INTERVENTIONS: Patients received CSE with intrathecal injection of 15 mg of 0.5% hyperbaric bupivacaine. All procedures started 8 to 10 AM, and operating room temperature was maintained between 21 degrees and 23 degrees C, with relative humidity ranging between 40% and 45%. For warming therapy, patients received active forced-air warming of either the two upper limbs (Group Upper body, n = 24), or the unoperated lower limb (Group Lower extremity, n = 24). Core temperature was measured before CSE placement (baseline), and then every 30 minutes until completion of surgery. Time for fulfillment of clinical discharging criteria from the recovery area was evaluated by a blinded observer. MEASUREMENTS AND MAIN RESULTS: Demographic data, duration of surgery, intraoperative blood losses, crystalloid infusion, and hemodynamic variables were similar in the two groups. Core temperature slightly decreased in both groups, but at the end of surgery the mean core temperature was 36.2 degrees +/- 0.5 degree C in Group Upper body and 36.3 +/- 0.5 in Group Lower extremity (NS). At recovery room arrival, seven patients in Group Upper body (29%) and three patients in Group Lower extremity (12.5%) had a core temperature less than 36 degrees C (NS). Shivering was observed in one patient in Group Upper body and in two patients in Group Lower extremity (NS). Clinical discharging criteria were fulfilled after 37 +/- 16 minutes in Group Upper body and 30 +/- 32 minutes in Group Lower extremity (NS). CONCLUSIONS: Forced-air cutaneous warming allows the anesthesiologist to maintain normothermia during CSE for total hip replacement even if the convective blanket is placed on a relatively small skin surface with reflex vasoconstriction. Placing the forced-air warming system on the vasodilated unoperated lower limb may be troublesome to the surgeons and does not offer clinically relevant advantages in warming efficiency.     

Combined administration of diltiazem and nicardipine attenuates hypertensive responses to emergence and extubation

Diltiazem and nicardipine, when injected as a mixture during anesthesia, reduce blood pressure in an additive manner without changing heart rate. The author evaluated the use of this mixture for controlling the blood pressure during emergence from general anesthesia and at extubation. The subjects included 15 preoperative hypertensive (HT) patients who underwent various types of surgery and 18 patients with subarachnoid hemorrhage (SAH) who underwent clipping of a cerebral aneurysm. General anesthesia was maintained with isoflurane or sevoflurane, supplemented with fentanyl. A mixed solution containing 2.5 mg diltiazem plus 0.5 mg nicardipine in 1 mL was injected intermittently every 2 to 4 minutes to bring the blood pressure to its resting level from cessation of inhaled anesthetics to extubation. Untreated patients who underwent similar types of surgery and anesthesia were selected for comparison. The average systolic blood pressure during emergence and at extubation increased to 156 +/- 19 mm Hg (mean +/- standard deviation) and 170 +/- 10 mm Hg in the untreated HT group, and increased to 157 +/- 16 mm Hg and 170 +/- 5mm Hg in the untreated SAH group. Systolic blood pressure was well controlled at 127 +/- 14 mm Hg and 145 +/- 14 mm Hg in the treated HT group with 3.7 +/- 1.9 mL of the mixture, and at 120 +/- 9 mm Hg and 137 +/- 20 mm Hg in the treated SAH group with 7.1 +/- 2.5 mL of the mixture. No significant difference (P < .05) in the heart rate was found between the untreated and the treated HT or SAH groups. Two patients in the treated SAH group exhibited tachycardia. The combined administration of diltiazem and nicardipine can help control blood pressure in patients with a possible HT response to emergence from general anesthesia and extubation.