Sedation management during therapeutic hypothermia for neonatal encephalopathy: Atropine premedication for endotracheal intubation causes a prolonged increase in heart rate

Aim

Heart rate (HR) plays an important role in the assessment of stress during therapeutic hypothermia (TH) for neonatal encephalopathy; we aimed to quantify the effect on HR of endotracheal (ET) intubation and drugs given to facilitate it. If atropine premedication independently increased HR, the main indicator of effective sedation, we hypothesised that increased sedation would have been given.

Methods

Thirty-two, term, neonates recruited into a randomised pilot study comparing TH and TH combined with 50% Xenon inhalation were studied. Indications for ET intubation included: resuscitation at delivery, clinical need and elective re-intubation with a cuffed ET tube if randomised to Xenon. Standard intubation drugs comprised one or more of intravenous morphine, atropine, and suxamethonium. Local cooling guidelines were followed including morphine infusion for sedation.

Results

At postnatal hours five to eight atropine increased HR in a linear regression model (p < 0.01). All other independent variables were excluded. Where more than one dose of atropine was given total morphine sedation given up to 8 h into the treatment period was significantly higher (p < 0.01).

Conclusion

We have shown that atropine premedication for ET intubation significantly increased HR, the main indicator of effective sedation and total morphine dose for sedation during early TH was increased where more than one dose of atropine was given. Bradycardia was not reported in any neonate, even without atropine premedication. We suggest that the use of atropine as part of standard premedication for ET intubation of term neonates undergoing TH should be reconsidered.     

头部亚低温治疗新生儿缺氧缺血性脑病的临床效果观察

目的:探讨头部亚低温治疗新生儿缺氧缺血性脑病的临床疗效。方法:将2008年5月~2010年7月我院NICU收治的82例中、重度新生儿缺氧缺血性脑病患儿随机分为观察组(n=49例)和对照组(n=33例),两组均采用降颅压、抗惊厥、维持酸碱平衡及营养支持等治疗,观察组在常规治疗的基础上又加用头部亚低温疗法。观察两组患儿抽搐发生率及存活率。结果:观察组患儿抽搐发生率低于对照组,存活率高于对照组。结论:头部亚低温治疗新生儿缺氧缺血性脑病疗效显著,治疗期间的临床观察及护理非常重要。     

新生儿窒息后脑损伤的CT诊断与临床研究

目的：为提高窒息后脑损伤的诊断率和探讨窒息程度与脑损伤的关系。方法：对３１ 例窒息新生儿头颅ＣＴ的检查并进行轻、重度窒息的ＣＴ对比研究。结果：显示ＣＴ诊断脑损伤的阳性率为５４．８４％ ,窒息程度与脑损伤的关系为： 轻度窒息组ＣＴ示脑损伤的发生率为４４％ , 重度窒息组为６６％ , 二者差异无显著性（Ｐ＜ ０．０５）。结论：提示ＣＴ是诊断窒息后脑损伤的可靠检查手段,脑损伤的产生与窒息程度无明显正相关,不能单靠出生时窒息的严重程度而判断脑损伤的发生与预后。     

亚低温对犬心脏骤停后脑水肿及血脑屏障的影响

目的观察亚低温干预对犬心脏骤停后脑水肿及血脑屏障的影响。方法共选取16只成年健康杂种犬，将其随机分为亚低温组（n=8）和对照组（n=8），采用诱发室颤的方法导致上述2组动物心跳、呼吸骤停，随后施行脑复苏程序；亚低温组动物在心跳骤停期间给予亚低温干预。采用双抗夹心酶联免疫吸附技术测定各组动物血清S100B蛋白含量，同时观察其脑组织含水量及病理学改变。结果亚低温组动物经亚低温干预后，发现其血清S100B蛋白含量显著低于对照组（P〈0．05），脑组织含水量也显著低于对照组（P〈0．05）；2组实验动物脑标本经病理学检测后发现，亚低温组动物脑组织缺氧损伤程度明显轻于对照组。结论亚低温干预能减轻心跳骤停实验犬的脑水肿程度，改善其血脑屏障功能，从而发挥脑保护效应。     

Transpulmonary hypothermia: A novel method of rapid brain cooling through augmented heat extraction from the lungs

Aim

Delay in instituting neuroprotective measures after cardiac arrest increases death and decreases neuronal recovery. Current hypothermia methods are slow, ineffective, unreliable, or highly invasive. We report the feasibility of rapid hypothermia induction in swine through augmented heat extraction from the lungs.

Methods

Twenty-four domestic crossbred pigs (weight, 50–55 kg) were ventilated with room air. Intraparenchymal brain temperature and core temperatures from pulmonary artery, lower esophagus, bladder, rectum, nasopharynx, and tympanum were recorded. In eight animals, ventilation was switched to cooled helium–oxygen mixture (heliox) and perfluorocarbon (PFC) aerosol and continued for 90 min or until target brain temperature of 32 °C was reached. Eight animals received body-surface cooling with water-circulating blankets; eight control animals continued to be ventilated with room air.

Results

Brain and core temperatures declined rapidly with cooled heliox–PFC ventilation. The brain reached target temperature within the study period (mean [SD], 66 [7.6] min) in only the transpulmonary cooling group. Cardiopulmonary functions and poststudy histopathological examination of the lungs were normal.

Conclusion

Transpulmonary cooling is novel, rapid, minimally invasive, and an effective technique to induce therapeutic hypothermia. High thermal conductivity of helium and vaporization of PFC produces rapid cooling of alveolar gases. The thinness and large surface area of alveolar membrane facilitate rapid cooling of the pulmonary circulation. Because of differences in thermogenesis, blood flow, insulation, and exposure to the external environment, the brain cools at a different rate than other organs. Transpulmonary hypothermia was significantly faster than body surface cooling in reaching target brain temperature.     

Therapeutic hypothermia following cardiac arrest: a review of the evidence

Aims and objectives: This paper aims to undertake a review on the current evidence available on therapeutic hypothermia (TH) following cardiac arrest. Background: The use of TH has been associated as a potential treatment for a number of medical conditions including head injury and cerebral vascular accidents. Within the past decade, there have been numerous studies focusing upon the use of hypothermia following cardiac arrest. This paper evaluates the research on the use of TH following cardiac arrest and provides recommendations for clinical practice. Evidence from randomized controlled trials that are reviewed in this paper found that neurological outcome and mortality were significantly improved following inducing hypothermia following cardiac arrest. Search strategies: The following databases were accessed: Bandolier, Embase, Medline, Science Direct, CINAHL, Blackwell Synergy, Nursing Collection, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews and the National Electronic Library for Health. The following key words were used to search the databases: ‘Therapeutic hypothermia’, ‘Induced hypothermia’, ‘cooling post cardiac arrest’ and ‘post cardiac arrest care’. Inclusion and exclusion criteria: Only evidences published within the past 10 years and written in English were included. Studies on TH for the treatment of raised intracranial pressure were excluded. Conclusions: All adult patients who have return of spontaneous circulation and remain unconscious following cardiac arrest should be considered for TH between 32°C and 34°C for at least 12–24 h as this will improve patient mortality and morbidity. Acute hospitals need to devise policies and guidelines on the use of TH following cardiac arrest that include methods on how to achieve effective cooling by cold i.v. infusions, ice packs or purchasing specific cooling mattresses.     

Hemodynamics and oxygenation changes induced by the discontinuation of low-dose inhalational nitric oxide in newborn infants

Objective To assess changes associated with nitric oxide (NO) discontinuation in neonates receiving inhalational NO therapy as a treatment for pulmonary hypertension of the neonate (PPHN).Design Prospective study.Setting A pediatric PICU in a university hospital.Patients and methods Ten neonates were included. NO discontinaution was attempted when the oxygenation index fell below 10. The mean NO concentration was 4.9±0.8 ppm. Each infant was studied over three successive 5-min periods and was assigned to either group 1 (NO ₁ ⁺ , NO ₂ ⁺ , NO^–) or group 2 (NO ₁ ⁺ , NO^–, NO ₂ ⁺ ).Measurements and results Postductal transcutaneous PO₂ (tcPO₂), postductal oxygen saturation with pulse oxymetry (SpO₂), systolic and diastolic blood pressure (BP), heart rate (HR), left ventricular shortening fraction (LVSF), cardiac output (CO), and ratio of pulmonary artery time to peak velocity and right ventricular ejection time (TPV/RVET) were similar during the two successive NO⁺ periods (group 1), thus demonstrating that the measurements were reproducible. NO removal (groups 1 and 2) did not modify systolic or diastolic BP, HR, CO, or LVSF but did induce a significant decline in SpO₂, tcPO₂ (–25±5%) and TPV/RVET ratio (–25±3%). No reinstitution reversed the effects of NO withdrawal on tcPO₂, SpO₂ and TPV/RVET ratio (group 2) without any changes in systemic hemodynamics.Conlusion The shut-off of lowdose NO induced in each patient a decrease in oxygen delivery that may be due to increased pulmonary vascular resistances and/or redistribution of pulmonary blood flow with ventilation-perfusion mismatching. The optimum weaning-off procedure of inhalational NO remains to be determined.     

亚低温对创伤性脑水肿大鼠一氧化氮及脑含水量的影响

目的观察亚低温治疗对创伤性脑水肿大鼠颈内静脉血一氧化氮(NO)及脑含水量的影响,并探讨亚低温的脑保护效应。方法共选取54只Wistar大鼠,将其随机分为对照组(6只)、常温损伤组(24只)及亚低温损伤组(24只),后2组大鼠又根据观察时间点不同细分为伤后30min亚组、伤后2h亚组、伤后4h亚组及伤后8h亚组。参照袁绍纪等介绍的方法将常温损伤组及亚低温损伤组大鼠制成创伤性脑水肿动物模型。采用化学发光法检测大鼠伤侧颈内静脉血NO含量,并运用Elliot公式计算伤侧脑组织水含量。结果常温损伤组大鼠于脑损伤后30min内即出现脑水肿,其脑含水量[(78.12±0.18)%]明显大于对照组[(77.63±0.21)%],差异有统计学意义(P<0.05);伤侧颈内静脉血NO含量[(3.561±0.251)μmol/L]也较对照组[(2.438±0.134)μmol/L]明显增高,差异亦有统计学意义(P<0.05)。常温损伤组大鼠脑含水量及NO含量于伤后8h达到峰值[此时脑含水量为(79.83±0.41)%,NO含量为(7.831±0.272)μmol/L]。亚低温治疗能明显降低脑水肿大鼠伤侧颈内静脉血NO含量,而且还能显著减轻其脑水肿程度。结论NO在创伤性脑水肿的发生及发展中具有重要作用,并且还与脑含水量具有同步变化的特点;亚低温治疗能明显减轻脑水肿程度,降低颈内静脉血NO含量,从而缓解继发性脑损伤,促进神经组织功能的早日康复,降低残死率。     

保温措施下腹部手术婴幼儿术中低体温发生的影响因素分析

目的探讨保温措施下腹部手术婴幼儿术中低体温发生的影响因素。方法对98例行腹部手术的婴幼儿术中实施保温措施,观察并记录婴幼儿的体温变化情况。分析腹部手术婴幼儿术中低体温发生的影响因素。结果 98例婴幼儿发生术中低体温42例,发生率为42.86%。体表面积、手术时间和术中输血是影响手术低体温发生的影响因素。结论腹部手术婴幼儿术中低体温发生率较高。在保温措施的基础上做好术前保温工作有利于降低婴幼儿腹部手术中低体温的发生。     

新生儿缺氧缺血性脑病血浆内皮素和皮质醇的变化及临床意义

目的 测定新生儿缺氧缺血性脑病（ＨＩＥ）患儿血浆内皮素（ＥＴ）及血清皮质醇（Ｃｏｒ）水平,探讨其含量变化及临床意义。方法 采用放射免疫分析技术（ＲＩＡ）分别测定３７例ＨＩＥ患儿急性期恢复期血浆ＥＴ,Ｃｏｒ的含量,并用１８例健康足月儿作对照。结果 急性期血浆ＥＴ,血清Ｃｏｒ水平,与对照组比较,中重度组明显升高（Ｐ均〈０．０１）,恢复期重度组ＥＴ与中度组Ｃｏｒ与对照组比较,仍有显著性差异（Ｐ〈０．０１     

早产儿脑损伤的诊断评估

目的 了解脑电图(EEG)及头颅B超(BUS)对早产儿早期脑损伤的诊断评估价值,并探讨EEG与BUS的诊断相关性.方法 对256例早产儿应用EEG描记和BUS在生后48 h及7 d各分别检查一次.对1月后BUS确诊的75例早产儿的神经发育每1～4周复查1次EEG,至少到纠正胎龄40～42周.结果 两种方法 在诊断早产儿脑损伤方面48 h差异有统计学意义(P＜0.05);7 d则无显著性差异(P＞0.05).在对1月BUS确诊的75例早产儿进行随访的过程中,有8例最后确诊为脑瘫.结论 BUS及EEG在诊断早产儿脑损伤方面不仅可以早期诊断并早期干预,且二者有诊断相关性,二者同时进行对判断早产儿脑损伤的时间和程度有很好的评价,对脑功能损伤的诊断及预后的评价具有重要意义.     

治疗性浅低温对脑心脏及其他器官的保护作用及机制

心脏骤停患者被实施心肺脑复苏时会产生不可避免的再灌注损伤,治疗性浅低温（ MTH）被证实可以对再灌注后的颅脑产生保护作用,治疗性浅低温同样被证实在心肌缺血或是急性心肌梗死（ AMI）中有保护作用,但在其他器官中是否有保护作用还有待进一步研究。治疗性浅低温其保护性作用机制及相应的并发症也有待进一步了解与完善。本文就治疗性浅低温对脑、心脏及其他器官的保护作用及其机制做一简要综述。     

局部亚低温干预对实验大鼠脑出血后MMP-2/9表达及脑水肿的影响

目的探讨局部亚低温干预对大鼠自体血注入法脑出血模型基质金属蛋白酶-2／9（MMP-2／9）表达及脑水肿的影响。方法将165只Wistar大鼠随机分为常温假手术组（15只）、常温实验组（75只）及亚低温实验组（75只）。亚低温实验组于脑内注血后给予持续4h的局部亚低温治疗。各组大鼠分别于术后6h，24h，72h，5d及7d时进行脑组织水含量、血脑屏障（BBB）通透性测定，并同时应用免疫组化法测定脑组织MMP-2／9表达水平。结果常温实验组大鼠脑组织水含量、BBB通透性及MMP-9表达水平均于术后6h时开始增高，于72h时达到高峰，至术后7d时仍明显高于常温假手术组；MMP-2在术后24h才开始有少量表达，于术后5d时达到高峰，至7d时仍保持较高表达水平。亚低温实验组大鼠脑组织水含量、BBB通透性及MMP-2／9的表达情况均与常温实验组接近，但其各项指标数据均较常温实验组明显降低。常温实验组和亚低温实验组大鼠MMP-9的表达与脑组织水含量及BBB通透性的变化均呈正相关，而MMP-2的表达与二者变化均无明显相关性。结论亚低温干预可能具有抑制脑出血后MMP-2／9表达的作用，从而保护BBB，减轻脑水肿及炎症反应。     

术中保温对婴幼儿腹部手术期间凝血功能及出血量的影响

目的探讨婴幼儿腹部手术期间术中保温对凝血功能及出血量的影响。方法将36例行腹部手术婴幼儿随机分为对照组与观察组,每组各18例。观察组采用输液加温器和充气升温毯结合温热水冲洗腹腔;对照组在常规温度下进行手术,输入液体、血液不作加温处理。测量患儿术中凝血指标及术中出血量,并进行统计学分析。结果两组患儿术中体温和出血量、凝血功能情况比较,经统计学分析,均P<0.01,差异有统计学意义。结论术中采用输液加温器和充气升温毯结合温热水冲洗腹腔方法,可防止低体温的发生,有效减少术中出血量和术后并发症的发生,提高了手术的安全性和成功率。     

亚低温治疗新生儿缺氧缺血性脑损伤的安全性监测与护理

目的验证选择性头部降温治疗新生儿缺氧缺血性脑损伤的安全性.方法 选择60例重度窒息足月儿,随机分成两组,每组30例.治疗组用选择性头部降温方法,维持直肠温度在(35±0.5)℃,持续头部降温72h,对照组不进行降温治疗,分别对两组进行心率、心律、呼吸频率、呼吸节律、经皮血氧饱和度、血压、尿量监测.用SPSS 10.0统计软件对监测数据进行t检验.结果治疗组除12～72h心率与对照组相比存在明显下降外(P<0.01),其余指标均无显著性差异.结论只要在护理上严密监测体温,保持直肠温度在(35±0.5)℃,用选择性头部降温治疗新生儿缺血缺氧性脑损伤是安全、可行的.     

A systematic review of safety and adverse effects in the practice of therapeutic hypothermia

Objective

To carry out a systematic review to estimate the rate and magnitude of adverse effects following therapeutic hypothermia (TH) procedure in patients resuscitated from out-of-hospital cardiac arrest (OHCA) and highlight the specific complications seen after the procedure.

Behavioral and physiologic adverse effects in adolescent and young adult emergency department patients reporting use of energy drinks and caffeine

Abstract

Introduction. This pilot study assessed the prevalence of physiologic and behavioral adverse effects among adolescent (13–17 years) and adult (18–25 years) emergency department patients who reported energy drink and/or caffeinated-only beverage use within the 30 days prior to emergency department presentation. It was hypothesized that energy drink users would report more adverse effects than those who used only traditional caffeinated beverages such as coffee, tea, or soft drinks. Methods. This cross-sectional pilot study was conducted in two urban emergency departments, one adult and one pediatric. Eligible patients were enrolled during a 6-week period between June and August 2010. Participants completed a tablet computer-based, self-administered, anonymous questionnaire about their past 30-day energy drink and/or caffeinated-only beverage use, substance use, and experience of 10 physiologic and 10 behavioral symptoms. Multivariable logistic regression and negative binomial regression models, adjusted for age, gender, and substance use, were created to compare the occurrence of each adverse effect between energy drink and caffeinated-only beverage users. Odds ratios (ORs) and incidence rate ratios (IRRs) were estimated. Results. Of those enrolled, 53.3% reported consuming energy drinks, 39.1% caffeinated-only beverages, and 7.6% no energy drinks or caffeinated-only beverages within the past 30 days. In multivariable logistic regression models, energy drink users were more likely than caffeinated-only beverage users to report having “gotten into trouble at home, school, or work” in the past 30 days (OR: 3.12 [1.24–7.88]). In the negative binomial regression multivariable models, more behavioral effects were reported among drug users (IRR: 1.50 [1.18–1.93]), and more physiologic effects were reported among tobacco users (IRR: 1.42 [1.13–1.80]) and females (IRR: 1.48 [1.21–1.80]), but not among energy drink users. Conclusions. Energy drink users and substance users are more likely to report specific physiologic and behavioral adverse effects. Emergency department clinicians should consider asking patients about energy drink and traditional caffeine usage and substance use when assessing patient symptoms.     

亚低温治疗在脑复苏中的应用及影响预后因素分析

目的 探讨影响心肺复苏(CPR)术后亚低温治疗患者预后的因素及动态脑电波监测对预后的价值.方法 对42例循环稳定的CPR术后患者在全身治疗的基础上进行亚低温治疗,体温(颈静脉球温度)控制在31～34℃,维持3～6 d后复温.治疗期间行各项常规检查,同时监测脑电波并进行Hockday分级,对于存活3个月者通过格拉斯哥预后评分(GOS)评估神经系统功能.结果 良好转归组(包括恢复良好、中度残疾,19例)与不良转归组(包括严重残疾、植物状态、死亡,23例)间停跳后至开始CPR时间及复苏后格拉斯哥昏迷评分(GCS)、血中剩余碱、乳酸浓度均存在不同程度差异[停跳后至开始CPR时间(min):4.11±1.80比13.08±11.37,GCS(分):5.48±1.32比4.13±1.61,剩余碱(mmol/L):-10.27±6.23比-13.18±7.29,乳酸(mmol/L):6.82±3.12比8.47±4.14,P＜0.05或P＜0.01];37例患者行动态脑电波监测,Hockday分级Ⅱ级与Ⅲ级间的良好预后率比较差异有统计学意义[85.7%(12/14)比37.5%(3/8),P＜0.05].结论 停跳后至开始CPR时间及复苏后GCS、血中剩余碱、乳酸浓度有助于判定亚低温治疗后患者的预后;脑电波监测对判定亚低温治疗后患者神经功能转归有较大帮助.