The use of transillumination for peripheral venous access in paediatric anaesthesia.
The use of transillumination for peripheral venous access in paediatric anaesthesia.
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透照法在小儿麻醉中外周静脉通路的应用。
DOI：
10.1017/s026502150524053x
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发表时间：
2005
影响因子：
3.6
通讯作者：
O. Oner
中科院分区：
文献类型：
--
作者：
H. Atalay;H. Erbay;E. Tomatir;S. Seri̇n;O. Oner
编者：一个自主呼吸的插管病人必须克服气管插管、呼吸机及其回路所施加的阻力。这通常被称为“呼吸的额外工作”。压力支持通气已被广泛用于补偿额外的呼吸功。然而，压力支持通气并不理想，因为它在整个吸气过程中施加恒定的正压[1]。最近，出现了两种替代通气模式：自动管道补偿和放大自发模式。自动管路补偿[2]仅用于补偿呼吸的额外功。它施加吸气气道压力，该压力根据患者通过气管导管产生的压降几乎瞬时变化。放大自主通气[3]是Vector XXI呼吸机中实施的另一种自主呼吸支持。它包括一个直接连接到气管导管的呼吸接口。在该装置中，结合了流量发生器、吸气和呼气阀、呼吸速度计、用于压力测量的连接和触发器的激活。容量和压力均未预设，但存在患者自发流量的放大系数（1到10之间）。连续计算患者的流量和作为气管导管提供的阻力的函数的所施加的吸气流量的比例变化。我们比较了这三种模式的能力，以补偿额外的工作呼吸和呼吸模式。与医院伦理委员会的批准，我们研究了30例术后患者（年龄65 - 8岁）在呼吸机脱机手术后重症监护室（ICU）。入选标准为计划的大手术（心脏、骨科、普外科或神经外科），需要机械通气，既往无肺部疾病。使用允许测量气管压力的埃德加气管插管（Rusch，USA）。在入住ICU时，开始控制性机械通气，患者随机分为三组：压力支持通气（Evita 4; Dräger，德国; n 10）、自动管路补偿（Evita 4; Dräger，德国; n 10）或放大自发模式（Vector XXI; Temel，西班牙; n 10）。维持受控通气，直至达到标准撤机标准。在撤机期间，所有三组最初均使用压力支持通气。当存在以下特征时，选择每组的模式：压力支持通气15 cmH 2 O，每分钟通气量10 L min-1，呼吸频率20 min-1，PaO 2：FiO 2比值27，PaCO 2在4.7和6 kPa之间，并且没有代谢紊乱。在每组中研究了四个支持水平，逐渐降低：压力支持通气15，10，5和0 cmH 2 O;自动管补偿100%，60%，20%和0%;放大自发模式8，6，4和1。拔管前的最后一步是T形管通气，这在所有组中被用作对照水平。在最低支持水平下（压力支持通气，0;自动管补偿，0;和放大自发模式，1），患者必须克服呼吸系统的整个阻力负荷，我们认为这构成了呼吸的总附加功。在每个支撑水平，包括T型呼吸，允许患者在测量前平衡15分钟。三组患者的呼气末压（0 cmH 2 O）和吸入氧分数（40%）相似。触发灵敏度被设定在...
EDITOR: A spontaneously breathing, intubated patient has to overcome the resistances imposed by the tracheal tube, the ventilator and its circuit. This is usually called ‘additional work of breathing’. Pressure support ventilation has been widely used to compensate for additional work of breathing. Pressure support ventilation is not ideal, however, because it applies a constant positive pressure throughout inspiration [1]. Recently, two alternative ventilatory modes have appeared: automatic tube compensation and amplified spontaneous pattern. Automatic tube compensation [2] was designed solely for the purpose of compensating for additional work of breathing. It applies an inspiratory airway pressure that varies almost instantaneously according to the pressure drop generated by the patient across the tracheal tube. Amplified spontaneous ventilation [3] is another spontaneous breathing support implemented in the Vector XXI ventilator. It includes a respiratory interface which is connected directly to the tracheal tube. In this device a flow generator, inspiratory and expiratory valves, a pneumotachograph, connections for pressure measurement and activation of the trigger are incorporated. Neither volume nor pressure is preset but there is an amplification factor (between 1 and 10) of the patient’s spontaneous flow. The patient’s flow and the proportional change of the applied inspiratory flow as a function of the resistance provided by the tracheal tube are continuously calculated. We have compared these three modes with respect to ability to compensate for additional work of breathing and breathing pattern. With Hospital Ethics Committee approval, we studied 30 postoperative patients (age 65 8 yr) during ventilator weaning in the post-surgical intensive care unit (ICU). Inclusion criteria were scheduled major surgery (cardiac, orthopaedic, general or neurosurgery), requiring mechanical ventilation and absence of prior pulmonary disease. An Edgar tracheal tube (Rusch, USA) that allows measurement of tracheal pressure was used. On admission to the ICU, controlled mechanical ventilation was initiated and the patients were randomized to one of three groups: pressure support ventilation (Evita 4; Dräger, Germany; n 10), automatic tube compensation (Evita 4; Dräger, Germany; n 10) or amplified spontaneous pattern (Vector XXI; Temel, Spain; n 10). Controlled ventilation was maintained until standard weaning criteria were achieved. During weaning, pressure support ventilation was used initially in all three groups. The mode of each group was selected when the following characteristics were present: pressure support ventilation 15 cmH2O, minute volume 10 L min 1, respiratory rate 20 min 1, PaO2: FiO2 ratio 27, PaCO2 between 4.7 and 6 kPa and absence of metabolic disorders. Four support levels were studied in each group decreasing progressively: pressure support ventilation 15, 10, 5 and 0 cmH2O; automatic tube compensation 100%, 60%, 20% and 0%; and amplified spontaneous pattern 8, 6, 4 and 1. The final step before extubation was T-piece ventilation, which was used as control level in all groups. At minimum support levels (pressure support ventilation, 0; automatic tube compensation, 0; and amplified spontaneous pattern, 1) the patients have to overcome the entire resistance load of the ventilatory system and we considered this to constitute the total additional work of breathing. At each support level, including T-piece breathing, the patients were allowed to equilibrate for 15min before measurements. End-expiratory pressure (0cmH2O) and inspired oxygen fraction (40%) were similar in all three groups. Trigger sensitivity was set at …