持续气道正压通气,T管及压力支持通气等条件下患者呼吸功…

目的：探讨从呼吸功角度评价呼吸机脱机方式优劣的可能性及其意义。方法：通过Ｂｉｃｏｒｅ ＣＰ－１００呼吸监测测定２２例患者在压力支持通气（ＰＳＶ）、持续气道内正压（ＣＰＡＰ）通气、Ｔ管及拔管后２小时等条件下的呼吸功的变化。结果：ＣＰＡＰ０．４９ｋＰａ（１ｋＰａ＝１０．２０ｃｍＨ２Ｏ）Ｔ管、ＰＳＶ０．４９ｋＰａ时，患者呼吸功依次逐渐降低。ＣＰＡＰ０．４９ｋＰａ时呼吸功（９．９８Ｊ／ｍｉｎ）比ＰＳＶ０．     

测定患者呼吸功对调整压力支持通气水平的意义

目的：评价患者呼吸功（ＷＯＢｐ）对调整压力支持通气（ＰＳＶ）水平的意义。方法：观测不同水平ＰＳＶ时，ＷＯＢｐ、呼吸机做功（ＷＯＢｖ）及呼吸频率（ＲＲ）、潮气量（ＶＴ）等指标的变化。结果：随ＰＳＶ水平增高，ＷＯＢｐ逐渐降低，ＷＯＢｖ逐渐增高；ＰＳＶ０时，ＷＯＢｐ为１．２２±０．４７Ｊ／Ｌ，ＰＳＶ在１．４７ｋＰａ时，ＷＯＢｐ和ＷＯＢｖ分别为０．３８±０．３１Ｊ／Ｌ和１．２９±０．１４Ｊ／Ｌ；ＷＯＢｐ与ＰＳＶ水平呈负相关（ｒ＝０．９９３；Ｐ＜０．０５），ＷＯＢｖ与ＰＳＶ水平呈正相关（ｒ＝０．９９９，Ｐ＜０．０５）；ＲＲ随ＰＳＶ增高而仅从２２．０次／分降至１７．２次／分，ＶＴ仅从０．３６Ｌ增至０．４９Ｌ。结论：随ＰＳＶ支持水平的提高，ＷＯＢｐ逐渐降低，以ＷＯＢｐ水平指导ＰＳＶ水平的调整，比ＲＲ、ＶＴ等常规监测指标更有意义。     

适应性支持通气在部分支持通气中对呼吸力学和呼吸功的影响

目的探讨适应性支持通气(ASV)在部分支持通气过程中对呼吸力学和呼吸功的影响。方法30例有自主呼吸的危重症机械通气患者,在同样的分钟通气量和呼气末正压(PEEP)的设置下,先给予AC1模式通气45min后改为ASV模式通气,时间为45min,结束后改为AC2模式(参数设置与AC1一致),通气时间为45min。记录上述三个45min后的呼吸力学和呼吸做功的参数。结果ASV模式下的气道峰值压和平均气道压下降明显,P分别小于0.01和0.05。ASV下的内源性PEEP(PEEPi)发生率为23.3%,明显低于AC1的PEEPi发生率46.7%(P<0.05)。ASV的器械附加功(WOBimp)和吸气压力时间乘积(PTP)明显降低(P<0.01)。而两种呼吸模式的血气分析和血液动力学,以及前后两次AC模式的各种参数变化无统计学意义(P>0.05)。结论在危重症的部分支持机械通气过程中,ASV较常规通气模式有利于实施保护性通气策略,同时降低呼吸负荷和呼吸做功,因而能降低呼吸氧耗。     

机械通气患者呼吸附加功影响因素的临床研究

目的　评价呼吸机、气管导管等器械阻力导致的附加功 (WOBimp)对患者呼吸功 (WOBp)的影响。方法　通过Ventrak 15 5 0呼吸监测仪 ,测定 18例患者不同机械通气条件下WOBp和WOBimp的变化。结果　持续气道正压 (CPAP) 5cmH2 O时 ,WOBp为 (10 14± 3 46 )J/min ,分别比压力支持通气 (PSV) 5cmH2 O和T管高 48 5 % (P <0 0 5 )和 2 3 7% (P >0 0 5 ) ,但比CPAP 0cmH2 O低 7 2 % (P >0 0 5 )。CPAP 5、 0cmH2 O和T管时 ,WOBimp占WOBp的比例分别为 5 8%、 5 1%和 42 %。CPAP 5cmH2 O时 ,WOBimp为 (0 78± 0 2 4)J/L ,分别比PSV 5cmH2 O〔(0 34± 0 13)J/L〕和T管〔(0 5 3± 0 14)J/L〕高 48 5 % (P <0 0 5 )和 2 3 7%(P <0 0 5 )。结论　呼吸机及气管导管导致的WOBimp使WOBp明显增加 ,气管导管是WOBimp明显增加的主要因素     

呼吸功对机械通气患者撤机的指导意义

目的：研究呼吸功（ＷＯＢ）对机械通气患者撤机的指导意义。方法：选择机械通气并准备撤机的患者２３例，应用ＢＩＣＯＲＥＣＰ１００呼吸监测仪床边监测患者ＷＯＢ及常规撤机指标〔呼吸频率（ＲＲ）、潮气量（ＶＴ）、每分通气量（ＶＥ）和最大用力吸气时口腔闭合压（ＭＩＰ）〕，观察其对撤机的指导意义。结果：１８例撤机成功，其中１０例ＷＯＢ正常（≤０．７５Ｊ／Ｌ），８例ＷＯＢ升高（１．００Ｊ／Ｌ～１．３１Ｊ／Ｌ）；撤机失败患者５例的ＷＯＢ〔（１．９６±０．７６）Ｊ／Ｌ（１．４５Ｊ／Ｌ～２．８６Ｊ／Ｌ）〕明显高于撤机成功的患者〔（０．７７±０．３６）Ｊ／Ｌ，Ｐ＜０．０５〕。常规撤机指标ＲＲ、ＭＩＰ、ＶＥ均显著高于撤机成功组，ＶＴ显著低于撤机成功组。结论：ＷＯＢ值对撤机有一定的指导意义，但并非敏感指标，需考虑肺部基础疾病，结合临床指标等综合因素判断是否撤机。     

呼吸功的评价及临床意义

呼吸功的评价及临床意义邱海波（综述）陈德昌（审校）作者单位：１００７３０中国医学科学院中国协和医院大学北京协和医院ＩＣＵ近年来，机械通气作为重要的器官功能支持手段，已广泛应用于临床。但呼吸支持的程度及何时脱机等仍是临床上常见的棘手问题。危重患者呼吸支...     

持续气道正压通气治疗阻塞性睡眠呼吸暂停低通气综合征研究进展

阻塞性睡眠呼吸暂停低通气综合征(obstructive sleep apnea hypopnea syndrome,OSAHS)是临床常见的睡眠呼吸疾病,其特点是睡眠期间上气道塌陷,导致低氧血症、高碳酸血症和睡眠结构破坏.CPAP是重度OSAHS和OSAHS伴心血管疾病患者的首选治疗方法,能有效改善症状及预后.予CPAP治疗前应作压力调定,固定气道压输出的CPAP对多数患者有效.开始治疗后应随访并评价疗效.CPAP的常见不良反应有面罩接触部位皮肤干涩、疼痛和皮疹.不同输出模式的CPAP的依从性、不良反应及远期疗效有待研究.     

持续气道正压-比例压力支持通气对机械通气参数的影响

比例压力支持 (proportional pres-sure support,PPS)模式是按患者瞬间吸气努力的大小 ,成比例地提供压力支持的同步支持通气模式。我们观察了该模式对机械通气参数的影响 ,报告如下。1　病例与方法1.1　病例 :纳入标准 :1因原发疾病需气管插管机械通气治疗 ;2循环稳定 ,无血流动力学异常及严重心律失常 ;3意识清醒 ;4自主呼吸规律。我院综合 ICU2 0 0 0年 1月— 2 0 0 1年 3月收治符合上述标准患者 42例 ,根据病情分为 2组 :慢性阻塞性肺疾病 (COPD)合并慢性呼吸衰竭急性加重组 (慢性呼衰组 ) 2 3例 ;急性呼衰组 19例 ,其中冠心病心力…     

双相气道正压通气在急性呼吸衰竭脱机过程的应用

目的：探讨双相气道正压通气（BIPAP）治疗急性呼吸衰竭的效果，评价BIPAP与压力支持通气（PSV）在脱机过程中的适用对象。方法：前瞻、随机将36例急性呼吸衰竭患者经APACHE-Ⅱ评分管理并充分齐同平衡．分为BIPAP治疗组和PSV治疗组：每种模式稳定30min后测定呼吸力学、血气指标、患者舒适度评分、治疗结束后记录脱机时间及并发症。结果：两种模式在患者呼吸功、舒适度评分、血气分析方面无统计学差异。结论：BIPAP与PSV均可应用于急性呼吸衰竭脱机过程．PSV更适用于自主通气努力较大患者：相较而言，BIPAP更能减少医务人员管理强度     

机械通气患者撤离呼吸机的护理

目的探讨机械通气患者撤离呼吸机过程中的护理措施。方法以临床护理学为基础,结合临床工作实践经验,总结机械通气患者撤离呼吸机过程的护理措施。结果通过正确及安全的护理措施,机械通气患者撤离呼吸机的成功率提高至95%。结论加强机械通气患者撤离呼吸机过程的护理,可帮助患者恢复正常自主呼吸功能,从而提高患者生活质量。     

A comparison of the imposed work of breathing in continuous positive pressure ventilation mode between three different ventilators

Abstract Objective: To compare the work of breathing imposed and patient tolerance to the delivery of face mask continuous positive pressure ventilation by three different ventilators. Methods: Eleven healthy volunteers were subject to continuous positive pressure ventilation at levels of 0, 5, 10 and 15 cmH₂O on each of the three machines tested (Oxylog 2000, Drägerwerk AG, Lubeck, Germany; Puritan-Bennett 7200, Puritan Bennett Corp., Carlsbad, CA, USA; Auspap, Ulco Engineering Pty Ltd, Marrickville, NSW, Australia). The work of breathing imposed by the machines was measured using the Bicore-CP100 pulmonary function monitor (Allied Healthcare Products, CA, USA). After breathing on the three machines, volunteers rated the comfort of breathing on a visual analogue scale. Results: The work of breathing imposed by the Oxylog 2000 was higher in all volunteers receiving face mask continuous positive pressure ventilation when compared with both the Puritan-Bennett 7200 and the Auspap. The Oxylog 2000 was considered to be the least comfortable. Conclusions: The provision of continuous positive pressure ventilation in the emergency department is becoming increasingly common, but the use of a transport ventilator, such as the Oxylog 2000, to provide this ventilatory support cannot currently be recommended.     

Bedside measurement of work of breathing

This paper describes the technique of measuring work of breathing, presented at the 13th International Symposium on Computers in Clinical Medicine and Anaesthesiology, Rotterdam, June 1992. Measuring work of breathing.has clinical uses in the Intensive Care Unit. Oxygen consumption does not truly reflect work of breathing. Mechanical work of breathing can be measured by recording continuous pressure and flow and integrating the resultant power. This method is facilitated at the bedside with the use of a PC computer and a spreadsheet program. It is further simplified by software to measure the area under the inspiratory pressure: volume loop.     

自主呼吸试验在撤机中的应用

目的 对应用自主呼吸试验(SBT)撤机方式与逐渐降低机械通气支持水平撤机方式成功拔管的患者进行比较,以寻找最佳撤机方式.方法 选择57例机械通气患者,病情稳定后通过撤机试验前评估,然后准备撤机.采用前后对照的方法将患者分为两组,2004年6月-2005年12月的21例患者作为对照组,采用逐渐降低机械通气支持水平的撤机方式拔管;2006年1月-2007年3月的36例患者作用为试验组,采用SBT的撤机方式拔管.分别观察两组患者的机械通气时间、住重症监护病房(ICU)时间、呼吸机相关性肺炎(VAP)发生率、48 h内再插管率、ICU病死率.结果 试验组与对照组的机械通气时间分别为(59.45±37.1)h和(111.4±59.8)h(P=0.001),住ICU时间分别为(8.0±5.5)d和(15.3±14.3)d(P=0.034),VAP发生率分别为16.7%和38.0%(P=0.070),48 h内再插管率分别为19.4%和5.0%(P=0.253),ICU病死率分别为25.0%和24.0%(P=0.920).结论 SBT的撤机方式比逐渐降低机械通气支持水平的撤机方式具有机械通气时间和住ICU时间短的优点,而两组VAP发生率、48 h内再插管率、ICU病死率基本相同.     

Weaning from mechanical ventilation with pressure support in patients failing a T-tube trial of spontaneous breathing

Objective Evidence that PS may facilitate weaning from mechanical ventilation (MV), although not confirmed by randomized trials, prompted us to investigate whether patients could be weaned with PS after failing a T-tube trial.Design and setting This was a prospective, non-randomized study in two French intensive care units.Patients and participants One hundred eighteen patients were enrolled and underwent a T-tube trial, after which 87 were extubated. Thirty-one underwent a further trial with PS, after which 21 were extubated.Interventions All patients under MV >24 h meeting the criteria for a weaning test underwent a 30-min T-tube trial. If this was successful, they were immediately extubated. Otherwise, a 30-min trial with +7 cm H₂O PS was initiated with an individualized pressurization slope and trigger adjustment. If all weaning criteria were met, the patients were extubated; otherwise, MV was reinstated.Measurements and Results The extubation failure rate at 48 h did not differ significantly between the groups: 11/87 (13%) versus 4/21 (19%), P=0.39. The groups were comparable with regard to endotracheal tube diameter, MV duration, the use of non-invasive ventilation (NIV) after extubation, initial severity score, age and underlying pathology, except for COPD. A significantly higher percentage of patients with COPD was extubated after the trial with PS (8/21–38%) than after a single T-tube trial (11/87–13%) (P=0.003).Conclusions Of the patients, 21/118 (18%) could be extubated after a trial with PS, despite having failed a T-tube trial. The reintubation rate was not increased. This protocol may particularly benefit patients who are most difficult to wean, notably those with COPD.     

Effect of pressure support ventilation on breathing patterns and respiratory work

We assessed the effect of pressure support ventilation (PSV) on breathing patterns and the work of breathing in 10 postoperative patients. Minute ventilation ( _E) increased by 8% with 5 cm H₂O PSV and 10% with 10 cm H₂O PSV compared to 0 cm H₂O PSV. The increase in _E was achieved by increased mean inspiratory flow (24% with 5 cm H₂O PSV and 67% with 10 cm H₂O PSV) and a decrease in duty cycle (13% with 5 cm H₂O PSV and 39% with 10 cm H₂O PSV). The decrease in duty cycle along with a decrease in respiratory frequency allowed a greater expiratory time including a rest period for the respiratory muscles, which might minimize the risk of muscle fatigue. Furthermore, the inspiratory work added by the ventilator was near zero with 5 cm H₂O PSV and 10 cm H₂O PSV. Oxygen consumption also decreased significantly with 5 cm H₂O PSV. We conclude that PSV improves the breathing patterns and minimizes the work of breathing spontaneously via a ventilator.     

Superimposed inspiratory work of the Siemens Servo 300 ventilator during continuous positive airway pressure

Objective To compare the superimposed inspired work of breathing (SIW) of the Siemens Servo 300 ventilator with the Siemens Servo 900 C ventilator.Design Comparisons made at continuous positive airway pressure (CPAP) levels of 0, 4, and 8 cmH₂O, and at trigger sensitivities of –1 and –2 cmH₂O, and flow triggering.Setting General intensive care unit in a University teaching hospital.Patients 7 patients receiving CPAP.Results At all levels of CPAP, the SIW was significantly less with the Siemens Servo 300 ventilator as compared to the Siemens Servo 900 C ventilator despite similar trigger sensitivities. No significant difference was found in the SIW of the Servo 300 ventilator when comparing trigger sensitivities of –1 cmH₂O, –2 cmH₂O, and flow triggering. Different levels of CPAP had no effect on SIW.Conclusions The Siemens Servo 300 ventilator entails less superimposed inspiratory work of breathing than the Siemens Servo 900 C ventilator.     

持续气道正压-比例压力支持-自动管道补偿与双水平气道正压-压力支持通气两种模式撤机方法的比较

目的 :比较持续气道正压比例压力支持自动管道补偿 (CPAP PPS ATC)与双水平气道正压压力支持通气 (BIPAP PSV)两种模式撤机方法的结果。方法 :CPAP PPS ATC组 42例 ,BIPAP PSV组 40例 ,采用对照研究方法 ,比较两种通气模式、起始参数的调节、解决通气机依赖特点及撤机成功率。结果 :两种模式的撤机成功率无明显差异 (P>0 .0 5 ) ,两种模式均无人机对抗 ,CPAP PPS ATC模式较 BIPAP PSV模式对通气机依赖患者有更大的自主性 ,更容易实现撤机。结论 :BIPAP PSV为压力控制与自主呼吸相结合模式 ,CPAP PPS ATC为自主模式 ,CPAP PPS ATC是一种更好的机械通气撤机模式     

自主呼吸试验在机械通气撤机过程中的应用

目的；探讨在终止机械通气后，自主呼吸试验（SBT）时间对成功拔管的作用。方法：采用回顾组与前瞻组对比的方法，回顾组将成功拔管患者按SBT时间不同及病种不同分别对SBT结果进行记录及统计不处理；前瞻组除慢慢阻塞性肺疾病（COPD）采用1－2小时SBT外，其余病种患者均采用30分钟SBT。记录并比较2组的成功率、再插管率，并进行统计学处理。结果：回顾组患者按时间分组显示，拔管成功率无显著性差异（P＞0.05）；若按病种分别计算，COPD1－2小时组成功率要高于30分钟组（P＜0.05），心力衰竭（心衰）患者30分钟组成功率高于3－4小时组（P＜0.05），与1－2小时组比较无显著性差异（P＞0.05）。前瞻组COPD及心衰组拔管成功率均较回顾组明显提高（P均＜0.05）。结论：应根据不同病种有用不同SBT。COPD患者SBT过短只能了解呼吸肌力，不能了解耐力；而心衰患者SBT过长会增加呼吸功而诱发心衰。     

浅快呼吸指数在两种自主呼吸试验方法中的临床研究

目的 观察应用压力支持通气(PSV)和T管(T-piece)方法进行自主呼吸试验(SBT)时浅快呼吸指数(RSBI)及其变化水平(ΔRSBI)对脱机成功的预测作用.方法 将2007年1-12月本科经口气管插管机械通气(MV)可脱机的208例患者随机分为PSV组(93例)和T-piece组(115例),分别进行30 min的SBT,记录两组患者在SBT 3 min和30 min时的气道闭合压(P0.1)、呼吸频率(f)、潮气量(VT),计算RSBI值及ΔRSBI,寻找预测脱机成功的阈值.结果 208例患者脱机成功168例,成功率80.77%;PSV组和T-piece组成功率分别为83.87%和78.26%(P>0.05).SBT 30 min时PSV组和T-piece组RSBI分别为(67.18±11.55)次·min-1·L-1和(99.11±15.53)次·min-1·L-1(P<0.01);ΔRSBI分别为(69±33)%和(119±35)%(P<0.01).PSV组RSBI与脱机成功的受试者工作特征曲线(ROC曲线)下面积为0.747±0.045(P=0.000),当RSBI为75次·min-1·L-1时,诊断准确率为87%;ΔRSBI与脱机成功的ROC曲线下面积为0.709±0.065(P=0.001),当ΔRSBI为90%时,诊断准确率为82%,即在SBT结束时RSBI增加水平≤90%预测脱机成功较好.T-piece组RSBI与脱机成功的ROC曲线下面积为0.821±0.049(P=0.000),当RSBI为100次·min-1·L-1时,诊断准确率为82%;ΔRSBI与脱机成功的ROC曲线下面积为0.738±0.046(P=0.000);ΔRSBI为130%时,诊断准确率为77%,即在SBT结束时RSBI增加水平≤130%预测脱机成功较好.结论 PSV组SBT 30 min时RSBI明显小于T-piece组,其数值分别为75次·min-1·L-1和100次·min-1·L-1时预测脱机成功较好;动态观察RSBI的变化对预测脱机成功很有价值.