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代写coursework,Weaning Patient Ventilation
发表日期:2013-09-29 08:46:09 | 来源:assignment.cc | 当前的位置:首页 > 代写coursework > 正文
Weaning Patient Ventilation

Introduction

The indications of mechanical ventilation are many. The main idea is patients are put to artificial ventilation to satisfy their bodies demand for oxygen and removal of carbon dioxide, since they cannot do this by themselves. Mechanical ventilation may be noninvasive through nasal or face masks or invasive through a tracheotomy tube. The time spent on mechanical ventilation varies.

It may be few hours as in cases of heart failure or obstructive airway disease. It may be for longer time as in cases of head injury or premature babies. Other patients may stay on artificial ventilation for unknown time as those in comas or with neurological condition where there is paralysis of the respiratory muscles. Being an aided respiration, so weaning and returning to the normal way of respiration has to be tried. However, the question remains when to wean and how to wean (Pruitt, 2006).

When to wean a patient from a ventilator

Frutos-Vivar and Esteban (2003) suggested an evidence-based weaning protocol on three steps. In step 1, on treatment follow up and daily assessment, when the patient’s condition improves, there are certain criteria to look for to start the process of weaning. These criteria are A) PO2/FIO2 (fraction of inspired oxygen) is 150-300. B) When positive end expiratory pressure is equal to or less than 5 cm/H2O and C) patient is awake with stable cardiovascular condition. D) Body temperature is less than 38 degrees C and hemoglobin is at 10 g/dl or more.

The second step is to give the patient a trial of short period for 30 minutes of spontaneous respiration using either a T-tube or a pressure support ventilation of 7cm/H2O. The criteria for trial success are both objective and subjective. Objective criteria are A) gas exchange criteria of SaO2 greater than 90 percent or PaO2 greater than 60 percent with Fio2 less than 0.4-0.5 and increase in PCO2 less than 10 mm Hg or decrease in pH less than 0.1. B) Heart rate should be less than 140 a minute or increased by less than 20 percent from baseline with systolic blood pressure higher than 80-160 mm Hg or change less than 20 percent from baseline.

Subjective signs include no extra work of respiratory or accessory respiratory muscles and absent signs of distress as agitation and increased sweating. If the trial succeeds, in other words the patient shows good tolerance to spontaneous respiration, the attending staff can wean the patient. If, on the other hand, the patient shows poor tolerance, the trial is to be repeated every 24 hours until good tolerance occurs, this is known as gradual weaning (Frutos-Vivar and Esteban, 2003).

How to wean a patient from mechanical ventilation

Weaning can be either gradual as discussed earlier or rapid. Rapid weaning is indicated in cases with no pulmonary or neurological disorders that mandate mechanical weaning. This is best illustrated in cases of postoperative indication as advised by the anesthetic consultant (Pruitt, 2006).

Pruitt, 2006 suggested a 12-point protocol for rapid weaning. First, the ventilator settings are those ordered by the anesthetic consultant,

  • 2) get arterial blood gases every 20 minutes, and always compare the results with readings of pulse oximetry and end tidal CO2 values.
  • 3) The patient observation sheet should include A- level of consciousness, B- temperature, and hemoglobin level. C- Gas exchange criteria and respiratory rate. All values discussed before apply for the timing of rapid weaning with slight variations among medical centers.
  • 4) Decrease intermittent mandatory ventilation (IMV) rate by two breaths/minute when the patient is awake and alert, responding appropriately, and assisting the ventilator. The patient SpO2 is greater than 92%, ETCO2 (end tidal CO2) is less than 40 mm Hg, and hemodynamic values are acceptable. Acceptable hemodynamic values are heart rate less than 120 a minute with no serious arrhythmias.
  • 5) Blood pressure is greater than 100 mm Hg systolic. In open-heart surgery, cardiac index, greater than two liters/minute/m2 without intraaortic balloon pump therapy, and chest tube drainage less than 100 ml/hour. If the patient is stable 15 to 30 minutes after the IMV rate is changed, continue decreasing the IMV rate by two breaths a minute every 15 to 30 minutes. Continue as long as the patient’s SpO2 stays above 92%, his ETCO2 is less than 40 mm Hg, and hemodynamic values are acceptable. Stop when the IMV rate equals two breaths a minute.
  • 6) adjust the FIO2 to 0.4 in increments of 0.05 to 0.1 as long as the patient’s SpO2 is above 92%.
  • 7) If the patient is receiving positive end-expiratory pressure (PEEP) of more than five cm H2O, decrease PEEP by five cm H2O every 30 minutes until PEEP is equal to five cm H2O, as long as the patient SpO2 is above 92%.
  • 8) Get an arterial blood gas analysis as needed and report the anesthesia consultant if the patient SpO2 falls below 92% or ETCO2 rises above 40 mm Hg or if he shows any signs of agitation or distress.
  • 9) Discontinue weaning if the patient cannot maintain acceptable hemodynamic, neurological, or respiratory parameters. Return to previous ventilator settings and notify the anesthetist.
  • 10) When the IMV rate equals two breaths a minute, get an arterial blood gas analysis, and correlate the results with the patient’s SpO2 and ETCO2 values. Get pulmonary function tests; the patient’s tidal volume should be greater than 5 cc/kg, spontaneous respiratory rate between 8 and 30 breaths/minute, vital capacity greater than 15 cc/kg, minute ventilation less than 10 liters/minute, and maximal inspiratory pressure less than -20 cm H2O. If readiness to wean criteria, haemodynamic, and lung mechanics criteria are met, place the patient on a T-tube at the current FIO2 and perform a spontaneous breathing trial.
  • 11) Get an arterial blood gas (ABG) analysis if the patient tolerates the spontaneous breathing trial for 30 minutes (as evidenced by the patient ability to stay on the T-piece with acceptable neurological, hemodynamic, and respiratory parameters).
  • 12) If the ABG results are in the acceptable criteria range, the patient will be extubated. Place the patient on supplemental oxygen at 5 to 6 liters/minute via nasal cannula (passive ventilation) to keep his Spo2 over 92%.

References

Pruitt, B. (2006). Weaning patients from mechanical ventilation. Nursing, 36 (9), 36-41.

Frutos-Vivar, F. and Esteban, A (2003). When to wean from a ventilator: An evidence-based strategy. Cleveland Clinic Journal of Medicine, 70 (5), 389-400.

 

介绍
机械通气的适应症有很多。其主要思想是把患者人工通气,以满足自己的身体需求的氧气和二氧化碳的去除,因为他们不能做到这一点,自己。通过气管切开套管可能通过鼻或面罩无创或有创机械通气。机械通气上花费的时间各不相同。
例心脏衰竭或气道阻塞性疾病,它可能是几个小时。这可能是头部受伤的情况下或早产儿更长的时间。未知的时间,因为那里是呼吸肌麻痹,昏迷或神经系统疾病,其他患者可能会留在人工通气。作为辅助呼吸,所以断奶,并返回到正常的呼吸方法,要尝试。然而,问题仍然存在,当断奶和如何断奶(普鲁特,2006年)的。
从呼吸机的病人戒掉
弗鲁托斯Vivar和Esteban (2003)建议以证据为基础的三个步骤断奶协议。在第1步,后续治疗和日常考核,当病人的病情好转,也有一定的标准来看待开始断奶的过程。这些标准是A ) PO2/FIO2 (吸入氧浓度)是150-300 。 B)当呼气末正压是等于或小于5 cm/H2O和C )与稳定的心血管疾病是清醒的病人。 D)体温低于38摄氏度,血红蛋白在10克/升或更多。
第二个步骤是,给病人短周期的试验进行30分钟的自发呼吸,使用一个T型管或压力支持通气7cm/H2O 。试验成功的标准都是客观的和主观的。目的的范围是A)的气体交换血氧饱和度大于90 %或氧分压与吸入氧浓度小于0.4-0.5和二氧化碳分压的增加小于10毫米汞柱或降低pH值小于0.1大于60%的标准。 B)心率应不超过140分钟或不到20% ,从基线收缩压高于80-160毫米汞柱或改变不到20% ,从基线增加。
主观的症状包括没有额外的工作的呼吸道或附件呼吸肌和缺席搅拌困扰的迹象,出汗增多。如果试验成功,换句话说病人显示出良好的耐受性的自主呼吸,与会人员可以断奶的病人。另一方面,如果病人出现耐受性差,审判要重复,每24小时,直到出现良好的耐受性,这被称为逐步断奶(弗鲁托斯Vivar和Esteban ,2003年) 。
如何戒掉机械通气病人
断奶可以是逐步的,如前面所讨论或快速。快速断奶的情况下表示没有肺部或神经系统疾病这一任务的机械断奶。在麻醉顾问(普鲁特2006 )告知术后指示的情况下,这是最好的说明。
普鲁特, 2006年提出了12点协议,快速断奶。首先,呼吸机的设置是那些下令麻醉顾问,
2)动脉血气每次20分钟,总是比较结果,脉搏血氧饱和度,呼气末CO2值读数。
3 )病人观察表应包括意识的A级,B温度,血红蛋白水平。 C-气体交换标准和呼吸频率。之前讨论的所有值为快速与医疗中心的轻微差异,断奶的时机。
4 )减少间歇指令通气( IMV)率, 2次/分钟时,病人是清醒和警觉,作出适当的回应,并协助呼吸。的患者血氧饱和度大于92% , ETCO2 (呼气末二氧化碳)是小于40毫米汞柱,血流动力学的值是可以接受的。可接受的心脏血流动力学值率小于120分钟,无严重心律失常。
5 )血压大于100毫米汞柱收缩压。心脏直视手术,心脏指数,大于二liters/minute/m2无主动脉内球囊反搏治疗,胸腔闭式引流少于100毫升/小时。如果病人是稳定的15至30分钟后, IMV率改变,继续IMV的汇率降低了呼吸一分钟,每15至30分钟。继续下去,只要病人的血氧饱和度保持在92%以上,他的ETCO2小于40毫米汞柱,血液动力学的值是可以接受的。 IMV率等于两个呼吸一分钟时停止。
6)调整FIO2到0.4 ,增量为0.05~ 0.1 ,只要患者的SpO2在92%以上的。
7)如果患者接受超过5 cm H2O的呼气末正压(PEEP ) ,减少PEEP PEEP 5 cm H2O的每30分钟,直到等于5厘米水柱,只要病人的血氧饱和度在92%以上。
8 )动脉血气分析的需要,如果病人的血氧饱和度低于92 %或高于40毫米汞柱或ETCO2上升搅拌或痛苦的任何迹象,他表示,麻醉顾问报告。
9)停止断奶如果病人不能维持可接受的血流动力学,神经,或呼吸参数。返回到先前的呼吸机参数设置和通知麻醉师。
10 )当IMV率等于一分钟,两口气,动脉血气分析,并与病人的血氧饱和度和ETCO2值相关的结果。获取肺功能检查;病人的潮汐体积应该是大于5毫升/公斤, 8和30次呼吸/分钟,至关重要的能力大于15毫升/千克,分钟通气低于10升/分钟之间的自发呼吸率,和最大吸气压力小于-20厘米H2O 。如果准备的断奶的标准,血流动力学,肺力学标准得到满足,这里的T形管上的病人在当前FIO2进行自主呼吸试验。
11 )如果病人动脉血气分析( ABG)容忍30分钟的自主呼吸试验(如病人的能力证明了留在可接受的神经系统,血液动力学和呼吸参数, T型管件) 。
12)如果ABG结果是在可接受的标准范围内,病人拔管。将病人供氧5~6升/分钟通过鼻导管被动通风,以保持他的血氧饱和度在92%以上。
参考文献
普鲁特, B. (2006) 。断奶机械通气的患者。护理, 36 (9 ) , 36-41 。
弗鲁托斯Vivar ,F和埃斯特万( 2003年) 。什么时候戒掉从呼吸机:基于证据的战略。克利夫兰诊所的期刊杂志, 70(5 ) , 389-400 。