Novamin infusion: a new method to cure postoperative shivering with hypothermia

Background

Postoperative shivering is a frequent complication of surgery in developing countries and there is no satisfying method to treat it, let alone to cure it. We studied whether intravenous amino acid (AA) infusion can cure postoperative shivering in the postanesthesia care unit.

Methods

Sixty postanesthesia care unit patients with shivering grade 2 or higher and tympanic temperature <36°C received randomly either infusion of Novamin 18 AAs (2 mL/kg/h), pethidine (0.5 mg/kg), or tramadol (1 mg/kg). Tympanic temperature, shivering grade, and thermal comfort were assessed every 5 min for 60 min. Blood glucose and lactic acid concentrations were measured before and after treatment. Postoperative nausea and vomiting were also recorded.

Results

Shivering stopped within 5 min in the pethidine and tramadol groups versus 90% stopped within 15 min in AA group. There were five cases of reshivering in the tramadol group versus none in the AA or pethidine groups. Tympanic temperature increased slowly in all patients but increased significantly faster in the AA group. Thermal comfort improved significantly faster in the AA group versus the other two groups, thermal comfort was significantly higher in the tramadol versus the pethidine group ≥35 min. Blood glucose concentration in AA group increased to 135.18 ± 9.18 mg/dL. There were some cases of nausea and vomiting in pethidine and tramadol groups but none in the AA group.

Conclusion

Novamin infusion can stop postoperative shivering and alleviates hypothermia and improves thermal comfort more effectively than tramadol and pethidine with less nausea and vomiting and causes a clinically acceptable blood glucose increase with no reshivering episodes.     

右美托咪定用于防治剖宫产术中寒战反应的适宜剂量

目的探讨右美托咪定用于防治剖宫产术中寒战反应的适宜剂量。方法选择单胎足月妊娠,拟在连续硬膜外麻醉下行择期剖宫产术的孕妇120例,随机分为四组,每组30例。胎儿娩出后,D1、D2、D3组分别输注负荷量右美托咪定0.2、0.5、0.8μg/kg,输注时间10 min,继以0.4μg·kg-1·h-1持续输注,关腹完毕后停药。N组则以0.1ml·kg-1·h-1的速率输注生理盐水。记录输注右美托咪定15min时产妇的寒战分级。结果 D2组和D3组寒战的发生率和程度分别低于D1组和N组(P0.05),而D2组和D3组差异无统计学意义。结论右美托咪定可有效防治剖宫术中寒战的发生,负荷量0.5μg/kg是一适宜剂量。     

Measurement and prediction of peak shivering intensity in humans

Prediction equations of shivering metabolism are critical to the development of models of thermoregulation during cold exposure. Although the intensity of maximal shivering has not yet been predicted, a peak shivering metabolic rate (Shiv_peak) of five times the resting metabolic rate has been reported. A group of 15 subjects (including 4 women) [mean age 24.7 (SD 6) years, mean body mass 72.1 (SD 12) kg, mean height 1.76 (SD 0.1) m, mean body fat 22.3 (SD 7)% and mean maximal oxygen uptake (V˙O_2max) 53.2 (SD 9) ml O₂ · kg⁻¹ · min⁻¹] participated in the present study to measure and predict Shiv_peak. The subjects were initially immersed in water at 8°C for up to 70 min. Water temperature was then gradually increased at 0.8 °C · min⁻¹ to a value of 20 °C, which it was expected would increase shivering heat production based on the knowledge that peripheral cold receptors fire maximally at approximately this temperature. This, in combination with the relatively low core temperature at the time this water temperature was reached, was hypothesized would stimulate Shiv_peak. Prior to warming the water from 8 to 20 °C, the oxygen consumption was 15.1 (SD 5.5) ml · kg⁻¹ · min⁻¹ at core temperatures of approximately 35 °C. After the water temperature had risen to 20 °C, the observed Shiv_peak was 22.1 (SD 4.2) ml O₂ · kg⁻¹ · min⁻¹ at core and mean skin temperatures of 35.2 (SD 0.9) and 22.1 (SD 2.2) °C, respectively. The Shiv_peak corresponded to 4.9 (SD 0.8) times the resting metabolism and 41.7 (SD 5.1)% of V˙O_2max. The best fit equation predicting Shiv_peak was Shiv_peak (ml O₂ · kg⁻¹ · min⁻¹)=30.5 + 0.348 ×V˙O_2max (ml O₂ · kg⁻¹ · min⁻¹) − 0.909 × body mass index (kg · m⁻²) − 0.233 × age (years); (P=0.0001; r ²=0.872). Accepted: 7 September 2000     

不同干预措施对减少全麻苏醒期寒战的对比研究

目的:探讨不同干预措施对全麻苏醒期寒战的影响。方法:选择100例妇科腹腔镜手术且在苏醒期发生寒战的患者,随机分为四组,每组25例。寒战发生后,A组给予充气式保温毯保暖;B组给予缓慢静脉注射曲马多1mg/kg;C组给予充气式保温毯保暖,缓慢静脉注射曲马多1mg/kg;D组为对照组,给予等量生理盐水静脉注射。观察并记录干预前(T1)、干预后5min(T2)和15min(T3)患者的寒战级别,患者的不良反应(恶心呕吐、头晕等)和返回病房后2h内寒战复发率,以及核心温度(鼓膜温度)的变化。结果:T1时点四组患者寒战程度无显著性差异(P>0.05);T2时点A、B、C组寒战等级低于D组(P<0.05),与A组比较,B、C组寒战疗效更好(P<0.05);T3时点A、B、C组疗效优于D组(P<0.05);A、B、C三组间比较C组疗效最佳(P<0.05)。四组患者各个时间点鼓膜温度无显著性差异(P>0.05)。返回病房后2h内寒战复发率C组明显低于A、B、D组(P<0.05);B、C组不良反应率比较无显著性差异(P>0.05)。结论:充气式保温毯加曲马多,对治疗全麻苏醒期寒战效果显著,不良反应少,且寒战复发率低。     

Prophylactic vs. therapeutic magnesium sulfate for shivering during spinal anesthesia

IntroductionShivering is one of the most common complications of neuraxial blockade. Some patients find shivering sensation worse than surgical pain. Therefore, both prevention and treatment of established shivering should be regarded as clinically relevant intervention in the perioperative period. The aim of our study is to compare the efficacy of magnesium sulfate when used for prevention or treatment of shivering following spinal anesthesia.MethodsIn this prospective, double blind, placebo controlled study, 120 ASA I, II patients undergoing surgery under spinal anesthesia were randomized into 3 groups. Following intrathecal injection, Group P (prophylactic) was given MgSO₄, 50 mg/kg I.V. bolus + 2 mg/kg/h infusion. Group T (therapeutic) was given MgSO₄ 50 mg/kg I.V. bolus as a therapy when shivering occurred. If shivering persisted, they received 25 mg/kg I.V. bolus. Group C (control) received saline at identical times. Meperidine was given as rescue if shivering persisted. Shivering grade 3/4 was regarded as significant. Core temperatures, incidence of shivering, and side effects were recorded.Main resultsTotal incidence of shivering, grade 3/4, was 15% in Group P, 45% in Group T, and 50% in Group C (p < 0.01). Magnesium sulfate significantly reduced the incidence and gain of shivering. The use of rescue meperidine was more in Group P (20%) and Group C (50%) compared to none in Group T (p < 0.05, p < 0.01, respectively). Significant reduction in core temperature occurred in the Mg groups compared to the control group p < 0.05. No correlation was found between patients who shivered and core temperature or ΔT. Hypotension was more frequent in Group P; nausea and vomiting were more in Mg groups than control group p < 0.05.ConclusionFollowing spinal anesthesia, prophylactic MgSO₄ infusion lowered incidence of shivering. When shivering did occur, MgSO₄ proved to be an effective treatment with minimal side effects.     

长托宁用于预防经尿道内镜下钬激光碎石术围术期寒颤

目的研究长托宁预防经尿道内镜下钬激光碎石术围术期寒颤的作用。方法 120例择期尿路结石的患者,随机分为两组,每组60例。实验组术前静脉注射长托宁0.5mg,对照组静脉阿托品0.5mg。观察记录患者心律变化、寒颤发生情况。结果实验组心律变化不明显,寒颤发生率低,和对照组比较有显著性差异。结论长托宁预防经尿道内镜下钬激光碎石术围术期寒颤较阿托品效果显著,且副作用少。     

椎管内麻醉后寒战发生的危险因素及预防的回顾性研究

目的 探讨椎管内麻醉后寒战发生的危险因素及预防方法.方法 对1008例接受椎管内麻醉患者进行术后随访,记录患者性别、年龄、ASA分级、手术类型、麻醉方式、预防性用药、局部麻醉药及麻醉后寒战的发生情况.结果 年龄与寒战发生呈负相关(B=-0.019,P＜0.05)；手术类型、麻醉方式与寒战发生具有相关性(P＜0.05)；蛛网膜下隙与硬膜外联合阻滞后寒战发生的可能性是蛛网膜下隙阻滞的1.851倍；预防性用药与寒战发生具有相关性(P＜0.05),预防性使用昂丹司琼+地塞米松患者麻醉后寒战发生的可能性只是无预防性用药患者的0.196倍；使用不同局部麻醉药与寒战发生具有相关性(B=0.443,P＜0.05),使用布比卡因行椎管内麻醉的寒战发生可能性是使用罗哌卡因的1.558倍.结论 椎管内麻醉后寒战发生的危险因素为年龄、手术类型、麻醉方式、不同局部麻醉药的使用,预防性联合使用昂丹司琼及地塞米松能有效预防椎管内麻醉后寒战的发生.     

低剂量舒芬太尼在剖宫产术麻醉中对寒战和牵拉痛的预防价值分析

目的探讨舒芬太尼对于剖宫产手术麻醉中的寒战(SV)、牵拉痛(DP)的临床预防作用。方法60例接受剖宫产的患者,根据选号法将其分为实验组和对照组,每组30例。实验组患者采用1 ml 0.75%布比卡因(Bupivacaine)、5μg舒芬太尼(Sufentanil)以及0.5 ml的10%葡萄糖麻醉;对照组患者采用1 ml的0.75%布比卡因以及0.5 ml的10%葡萄糖麻醉。比较两组患者的SV、DP发生情况以及踝关节恢复时间。结果实验组患者的SV、DP发生情况均明显优于对照组,差异均具有统计学意义(P<0.05)。两组患者踝关节恢复时间比较,差异无统计学意义(P>0.05)。结论剖宫产麻醉中加用低剂量的舒芬太尼可以很好地减少寒战、牵拉痛的发生,且对术后恢复无明显影响。     

布托啡诺对椎管内麻醉后寒战的疗效

目的:观察布托非诺对椎管内麻醉后寒战的治疗效果。方法:选择椎管内麻醉后出现寒战的患者70例,随机分成试验组(布托非诺1mg)和对照组(生理盐水5ml),给药前以及给药后在3min和5min时分别记录MAP和SpO2,同时观察寒战改善情况。结果:布托非诺对寒战的控制有效率3min时达94.29%,显著高于生理盐水对照组(P<0.01),且5min时的MAP优于对照组。结论:布托啡诺对椎管内麻醉后寒战能有效控制且未发现明显MAP和SpO2的负面影响。     

Thermosensitivity is reduced during fever induced by Staphylococcus aureus cells walls in rabbits

Thermosensitivity (TS) and threshold core temperature for metabolic cold defence were determined in six conscious rabbits before, and at seven different times after i.v. injection of killed Staphylococcus aureus (8⋅10⁷ or 2⋅10⁷ cell walls⋅kg⁻¹) by exposure to short periods (5–10 min) of body cooling. Heat was extracted with a chronically implanted intravascular heat exchanger. TS was calculated by regression of metabolic heat production (M) and core temperature, as indicated by hypothalamic temperature. Threshold for cold defence (shivering threshold) was calculated as the core temperature at which the thermosensitivity line crossed preinjection resting M. The shivering thresholds followed the shape of the fever response. TS was significantly reduced (up to 49%) during the time course of fever induced by the highest dose of pyrogen only. At both high and low doses of pyrogen TS correlated negatively with shivering threshold (r = 0.66 and 0.79 respectively) with similar slopes. The reduction in TS during fever was thus associated with the increase in shivering threshold resulting from the pyrogen injection and not by the dose of pyrogen. Model considerations indicate, however, that changes in sensitivity of the thermosensory input to the hypothalamic controller may affect threshold changes but cause negligible TS changes. It is more likely that the reduction in TS is effected in the specific hypothalamic effector pathways. Received: 25 August 1995/Received after revision: 27 November 1995/Accepted: 30 November 1995