中心静脉血氧饱和度对困难脱机病人拔管失败预测价值的临床研究

目的探讨中心静脉血氧饱和度(ScvO2)对困难脱机病人拔管失败的预测价值。方法机械通气超过48 h的困难脱机病人,其中成功经历两步脱机策略后给予拔除气管插管的病人入选为进一步的研究对象。拔管失败定义为在48 h内需要重新插管。根据定义进一步分为拔管成功(ES)组和拔管失败(EF)组,测量病人自主呼吸试验(SBT)前1 min及后30 min的各项参数。结果再插管率为32%。ScvO2的ROC曲线分析显示SBT开始后30 min,ScvO2下降5.4%,敏感性93%,特异性88%。结论 ScvO2是困难脱机病人拔管失败的一个早期的预测因子,下降5.4%以上可作为预测阈值。     

自主呼吸试验在机械通气脱机过程中的应用

目的 自主呼吸试验(SBT)作为程序化拔管步骤在机械通气脱机过程中的应用.方法 程序化拔管患者行前瞻性研究,非程序化拔管患者行回顾性分析,比较两组机械通气时间、呼吸机相关性肺炎(VAP)发生率、48 h复插管率、住ICU天数及ICU病死率.对于程序化拔管组患者,比较SBT成功与SBT失败、拔管成功与拔管失败组SBT前后监测指标的变化.结果 程序化拔管组较非程序化拔管组机械通气小时数(经Ln数据转换后)缩短(4.01±0.71 vs 4.51±0.85,P<0.05).住ICU天数(经Ln数据转换后)缩短(1.86±0.82 vs 2±48±0.92±P<0.05),VAP发生率及48 h复插管率差异无统计学意义.程序化拔管组SBT成功与SBT失败患者SBT前后心率、呼吸频率、浅快呼吸指数(f/Vt)、PaC_2的变化差异有统计学意义;而拔管成功与拔管失败患者SBT前后监测指标的变化差异无统计学意义.5例拔管失败患者中3例由于痰液引流障碍导致48 h内复插管.结论 程序化拔管可缩短机械通气时间.减少住ICU天数,不增加48 h复插管率.SBT前后心率、呼吸频率、f/Vt、PaCO_2变化对于判断SBT是否成功较其他指标更为重要.对于拔管后可能存在痰液引流障碍的患者需谨慎拔除气管插管.     

自主呼吸试验前后下腔静脉变异度对呼吸衰竭合并心功能不全患者撤机失败的预测价值

目的评价自主呼吸试验(SBT)前后下腔静脉变异度(△DIVC)对呼吸衰竭合并心功能不全患者机械通气后撤机失败的预测价值。方法选取2016年11月至2018年2月在徐州市中心医院ICU进行机械通气的呼吸衰竭合并心功能不全患者120例。患者30 min SBT成功后拔管,48 h内不需要再次气管插管和无创呼吸机辅助为撤机成功组(n=62);30 min SBT失败或者SBT成功后拔管,但48 h内需要再次插管或无创呼吸机辅助为撤机失败组(n=58)。分别在SBT前和30 min后记录并比较2组患者的临床特征及△DIVC。采用SPSS 17.0软件统计分析。根据数据类型,组间比较采用独立样本t检验、Mann-Whitney U检验或χ~2检验。采用多因素logistic回归法分析影响撤机失败的独立危险因素。利用受试者工作特征(ROC)曲线评估△DIVC对撤机失败的预测价值。结果 2组患者在慢性呼吸疾病、急性生理学和慢性健康状况评价Ⅱ(APACHEⅡ)评分、第1次插管到拔管的持续时间和血红蛋白水平方面比较差异有统计学意义(P0.05)。与撤机成功组比较,撤机失败组患者在SBT前及30 min后二氧化碳分压和N端脑钠肽前体显著升高,左室射血分数(LVEF)显著降低,差异有统计学意义(P0.05);在SBT后30 min,撤机失败组患者△DIVC较撤机成功组显著升高,差异亦有统计学意义(P0.05)。多变量logistic回归分析显示,LVEF(OR=1.204,95%CI 1.133～1.381;P=0.015)和SBT后30 min的△DIVC(OR=1.450,95%CI 1.102～2.026;P=0.009)是患者撤机失败的独立危险因素。SBT后30 min的△DIVC预测患者撤机失败的ROC曲线下面积为0.905,最佳截断点0.27,灵敏度为82.4%,特异度为94.4%。LVEF预测患者撤机失败的曲线下面积为0.806,最佳截断点为42.0%,灵敏度为54.5%,特异度为86.8%。结论 SBT 30 min后的△DIVC对于呼吸衰竭合并心功能不全患者撤机失败具有较高的预测价值。     

SBT联合BNP监测对COPD患者拔管结局的预测价值

目的探讨自主呼吸试验(SBT)联合脑钠肽(BNP)预测慢性阻塞性肺疾病(COPD)患者拔管结局价值.方法选择2016年1月至2018年12月广东同江医院重症监护室收治的需要行有创机械通气的COPD呼吸衰竭患者80例,根据最终成功拔管与否分为拔管成功组和拔管失败组.分别记录SBT试验前及通过SBT试验2h后患者BNP、血气分析结果,比较SBT前后BNP差值△BNP和△BNP的受试者工作特征曲线及曲线下面积.结果(1)SBT前,2组BNP水平差异无统计学意义(t=0.040,P>0.05),SBT后,拔管失败组BNP水平高于拔管成功组(t=23.458,P<0.05).(2)SBT前,2组pH、动脉血二氧化碳分压、动脉血氧分压差异均无统计学意义(t=1.030、0.481、0.585,P值均>0.05),SBT后,拔管失败组pH、动脉血氧分压低于拔管成功组(t=5.678、2.012,P值均<0.05),动脉血二氧化碳分压高于拔管成功组(t=5.098,P<0.05).(3)△BNP AUC大于SBT前BNP和SBT后BNP,△BNP的cut-off值为45 ng/L,特异度为95.66%,敏感度为83.32%,预测脱机后拔管失败准确率为93.11%.结论对于COPD合并心功能不全患者,达到撤机标准后,在进行SBT基础上评价SBT前后△BNP水平可有效预测COPD合并心功能不全患者撤机拔管成功率,可在临床广泛推广使用.     

自主呼吸试验在COPD机械通气患者撤机中的作用

目的评估自主呼吸试验（SBT）在COPD机械通气患者撤机过程中的作用。方法选择52例COPD机械通气撤机成功的患者,分为两组：S组24例,采用SBT方式撤机拔管;NS组28例,采用逐渐降低机械通气支持水平的方式撤机拔管。对比两组患者的拔管时间、住重症监护病房（ICU）时间、呼吸机相关性肺炎（VAP）发生率、48 h内再插管率以及住院病死率。结果 S组与NS组的拔出气管插管时间120 min和（300.01±65.23）min）、住ICU时间（9.50±4.20）d和（18.60±10.30）d、VAP发生率12.50%和28.57%,均有统计学差异（P〈0.05）,而48 h内再插管率20.83%和21.43%、ICU病死率16.67%和17.85%,无统计学差异（P〉0.05）。结论应用SBT法撤机比渐减机械通气支持水平的方法具有更早拔出气管插管、住ICU时间短的优点,而且降低了VAP的发生率。     

脉搏灌注指数和脉搏灌注变异指数在机械通气患者撤机中的应用

目的 观察脉搏灌注指数（PI）和脉搏灌注变异指数（PVI）在机械通气患者撤机中的应用效果。方法 选取116例准备撤机的机械通气患者,通过撤机筛查后采用T-管模式进行自主呼吸试验（SBT）,以患者拔管后自主呼吸时间超过48 h为撤机成功,根据撤机结果将患者分为撤机成功组（90例）和撤机失败组（26例）,使用脉搏血氧仪Radical-7监测SBT前和SBT结束时患者PI、PVI,计算SBT前后PI和PVI的变化（ΔPI、ΔPVI）,利用ROC评估SBT前PI、PVI及ΔPI、ΔPVI对机械通气患者撤机结果的预测价值。结果 与撤机失败组比较,撤机成功组SBT前PVI、SBT后PI、SBT后PVI、ΔPI、ΔPVI增加（P均<0.05）。当SBT前PVI>14.0%时,其预测机械通气患者撤机成功的灵敏度为86.1%,特异度为79.2%,AUC为0.860,95%CI为0.766～0.953;当ΔPVI>10.5%时,其预测机械通气患者撤机成功的灵敏度为91.7%,特异度为83.3%,AUC为0.905,95%CI为0.831～0.978;当ΔPI>12.5%时,其预测机...     

膈肌功能对慢性阻塞肺疾病加重期插管患者撤机的指导价值分析

目的探讨膈肌功能对慢性阻塞性肺病加重期(AECOPD)插管患者撤机的指导价值。方法选取行机械通气并考虑撤机的AECOPD插管患者为研究对象,根据患者撤机成功与否分为撤机成功组与撤机失败组。具备撤机条件后行自主呼吸试验(SBT)30 min,监测SBT 0、5、30 min时膈肌电活动(Edi)、呼吸浅快指数(f/Vt)及口腔闭合压(P0.1)。结果 37例患者纳入本研究,其中撤机成功组25例,撤机失败组12例。撤机失败组患者血Pa CO2高于另一组患者(P0.05)。撤机成功与失败组患者的年龄、Pa O2、MAP等各方面均无显著差异(P0.05)。SBT 30 min时两组患者Edi均显著高于SBT 0 min;在SBT 30 min撤机成功组Edi低于撤机失败组,以Edi12V为临界值,撤机失败预测的灵敏度为100.0%和特异度为66.7%。在SBT 5、30min时撤机成功组患者f/Vt较撤机失败组低,两组患者P0.1无明显差别(P0.05)。结论 Edi对AECOPD患者撤机具有良好的预测价值。     

浅快呼吸指数指导缺血性脑卒中患者撤机的临床观察

目的探讨浅快呼吸指数(RSBI)指导缺血性脑卒中患者撤机的临床价值。方法前瞻性研究,入选在重症医学科进行有创机械通气24 h 40例缺血性脑卒中患者,根据撤机结果将患者分为成功组26例,失败组14例。应用低水平压力支持通气法进行自主呼吸实验(SBT),40例患者均通过了1 h的自主呼吸实验,记录SBT前和SBT1h、SBT1.5h及SBT2h的RSBI,同时记录年龄、性别、APACHEⅡ评分、撤机前30 min的血气分析。结果成功组和失败组年龄、性别、GCS评分、APACHEⅡ评分无明显差异(P0.05),失败组合并冠心病比例较成功组明显升高(P0.05)。以RSBI≤105 bpm/L为标准预测撤机成功的灵敏度和特异度分别为:SBT前93.8%、10.6%,SBT1 h 100%、40.24%、SBT1.5 h 98.2%、38.7%SBT2 h 96.3%、38.2%。结论SBT1 h的RSBI预测缺血性脑卒中患者撤机成功的准确率高。动态观察RSBI对缺血性脑卒中患者成功撤机有一定的预测价值。     

探讨浅快呼吸指数指导COPD患者撤机的临床价值

目的评价浅快呼吸指数（rapid-shallow-breathing index,RSBI）作为COPD患者撤机的临床价值。方法呼吸重症监护病房的20例机械通气的COPD患者,均通过了1h的自主呼吸实验（spontaneous breathing trial,SBT）。记录两个时期的RS-BI：SBT前、SBT1h。同时记录年龄、性别、APACHEⅡ（acute physiology and chronic health evaluationⅡ）评分、撤机前的动脉血气分析。结果 16例COPD患者成功撤机,4例患者撤机失败。在成功和失败两组间年龄、性别、APACHEⅡ评分无明显差异（P〉0.05）,PaCO2（partial pressure of carbon dioxide in arterial blood）有明显差异（P〈0.05）。以RSBI≤105bpm/L为标准预测撤机成功的灵敏度和特异度分别为：SBT前RSBI93.8%、10%;SBT1h的RSBI93.8%、45.5%。SBT1h的RSBI与PaCO2联合预测撤机成功的灵敏度为89.5%,特异度为78%。结论 SBT1h的RSBI预测COPD患者成功撤机的准确性高于SBT前,其与PaCO2联合评价将提高预测撤机成功的准确性。     

浅快呼吸指数、中心静脉血氧饱和度及其变化率对机械通气患者拔管成功率的预测价值

目的:探讨浅快呼吸指数(RSBI)、中心静脉血氧饱和度(SCVO_2)及其变化率(ΔSCVO_2)对机械通气患者拔管成功率的预测价值。方法:采用前瞻性研究方法,选取重症监护室的机械通气患者70例次,按拔管结果分成拔管成功(ES)组和拔管失败(EF)组,比较2组SCVO_2、ΔSCVO_2及RSBI。结果:2组患者性别、年龄差异无统计学意义(P0.05)。2组自主呼吸试验(SBT)30min SCVO_2、ΔSCVO_2及RSBI差异有统计学意义(P0.05)。SBT 30 min SCVO_2与拔管成功率正相关(r=0.283,P=0.025),ΔSCVO_2和RSBI与拔管成功率负相关(r=-0.425,-0.282,P=0.001,0.025)。SBT 30min SCVO_2、ΔSCVO_2和RSBI的ROC下面积分别为0.697、0.810、0.651。结论:SBT 30 min SCVO_2、ΔSCVO_2和RSBI对机械通气患者拔管成功率具有一定的预测价值,ΔSCVO_2、SBT 30 min SCVO_2优于RSBI。     

Comparison of two methods for weaning patients with chronic obstructive pulmonary disease requiring mechanical ventilation for more than 15 days.

We designed a prospective multicenter randomized controlled study in three long-term weaning units (LWU) to evaluate which protocol, inspiratory pressure support ventilation (PSV) or spontaneous breathing trials (SB), is more effective in weaning patients with chronic obstructive pulmonary disease (COPD) requiring mechanical ventilation for more than 15 d. Fifty-two of 75 patients, failing an initial T-piece trial at admission, were randomly assigned to PSV or SB (26 in both groups). No significant difference was found in weaning success rate (73% versus 77% in the PSV and SB group, respectively), mortality rate (11.5% versus 7.6%), duration of ventilatory assistance (181 +/- 161 versus 130 +/- 106 h), LWU (33 +/- 12 versus 35 +/- 19 d), or total hospital stay. The results of these defined protocols were retrospectively compared with an "uncontrolled clinical practice" in weaning historical control patients. The overall 30-d weaning success rate was significantly greater (87% versus 70%) and the time spent under mechanical ventilation by survived and weaned patients was shorter in the patients in the study than in historical control patients (103 +/- 144 versus 170 +/- 127 h). The LWU and hospital stays were also significantly shorter (27 +/- 12 versus 38 +/- 18 and 38 +/- 17 versus 47 +/- 18 d). Spontaneous breathing trials and decreasing levels of PSV are equally effective in difficult-to-wean patients with COPD. The application of a well-defined protocol, independent of the mode used, may result in better outcomes than uncontrolled clinical practice.     

不同撤机指标对慢性阻塞性肺疾病患者撤机的预测价值研究

目的比较不同撤机指标对COPD患者撤机的预测价值。方法选取机械通气48h以上且已达到撤机标准的17例COPD患者,采用T型管方法进行自主呼吸试验2h,在自主呼吸试验进行30min时检测气道闭合压（P0.1）、最大吸气压（Pimax）和呼吸浅快指数（RSBI）值,探讨它们在预测COPD患者撤机中的价值。结果lO例COPD患者撤机成功,7例失败。成功组患者的P0.1,和RSBI值明显小于失败组,而Pimax值则明显大于失败组,其差异均具有显著统计学意义（P〈0．05）。P。预测COPD患者撤机的价值明显优于Pimax和RSBI,其灵敏度、特异性和准确性均高于Pimax和RSBI,它们分别为89％、75％和82％。结论P0．1、Pimax和RSBI对COPD患者的撤机均具有指导意义,其中P0．1的价值最大。     

静动脉二氧化碳分压差在法洛四联症患者围术期心功能监测中的意义

目的:探讨经过术后上腔静脉血氧饱和度(ScvO2)>60%的法洛（Fallot）四联症患者是否能够应用静动脉二氧化碳分压差(Pcv aCO2)作为Fallot四联症围术期心排出量评估指标。方法:87例术后早期ScvO2>60%的Fallot四联症矫治患者,根据术后即刻Pcv-aCO2是否≥8 mmHg,分为高 Pcv-aCO2组（34例）和低Pcv aCO2组（53例）。观察2组患者在术后即刻,8、12、24和48 h时的血流动力学指标,灌注指标,心功能状态,恢复情况。结果:低Pcv-aCO2 组心指数（CI ）明显高于高Pcv aCO2组(P<0.05),乳酸（Lac）、再插管率,无创呼吸机应用率,呼吸机辅助时间,住ICU时间及并发症均明显低于高Pcv-aCO2组(P<0.05);CI与全心舒张末容积（GEDV）正相关。结论:Fallot四联症患者术后早期Pcv-aCO2≥8 mmHg提示心排量不足,术后并发症的发生与早期高Pcv-aCO2水平有明显关系。     

智能化撤机和经验性撤机的前瞻性随机对照研究

目的 比较智能化撤机和经验性撤机两种撤机方法对机械通气撤机困难患者的疗效.方法 采用前瞻性随机对照研究,按平衡指数最小的原则进行简易的临床试验随机化分组,将62例综合ICU内的撤机困难患者随机分入智能化Smart Care组(SC组,30例)和同步间歇指令通气联合压力支持通气组(SP组,32例)进行撤机试验,两组患者的疾病构成、年龄、性别、入ICU时急性生理慢性健康状况评分(APACHE)Ⅱ以及撤机前机械通气时间差异均无统计学意义.两组患者除撤机方法不同外,其他处理均相同,观察两组的撤机时间、再插管率和机械通气相关并发症的发生率以及ICU滞留率.结果 SC组神经肌肉病变患者、术后呼吸支持患者和呼吸系统疾病患者的撤机时间分别为(49±13)、(67±37)和(25±96)h,明显少于SP组[分别为(223±38)、(106±34)和(502±91)h,X~2值分别为8.33、4.77和4.43,均P<0.05].SC组神经肌肉病变患者、术后呼吸支持患者的ICU滞留时间分别为(9.0 ±1.7)和(7.3±1.9)d,明显低于SP组的(20.8±5.1)和(14.6±1.7)d(X~2值分别为6.74和7.68,均P<0.05).SC组平均调节呼吸机次数为(5±1)次/人明显低于SP组的(13±3)次/人(t=2.73,P<0.05).两组的再插管率、气管切开率、气胸发牛率、呼吸机相关性肺炎(VAP)发生率和皮下气肿发生率比较差异均无统计学意义.结论 CDW智能化撤机法应用于撤机困难患者能够有效地缩短撤机时间,减少ICU滞留时间,并可以减少医生调节呼吸机的负担而节约医疗资源.     

中心静脉血氧饱和度对心脏术后休克患者容量复苏液体反应性的预测

目的 评价中心静脉血氧饱和度（Scv02）在扩容前后的变异是否可以成为鉴别心脏术后休克患者容量治疗有无反应的一个指标.方法 入选18例心脏术后需要扩容的休克患者,共进行了30次液体负荷试验.所有患者都放置了桡动脉插管、双腔锁骨下静脉或颈内静脉置管和PiCCO导管.在每一次扩容前后测定心脏指数（CI）、ScyO2,并将液体负荷后CI增加值（△CI）≥15％定义为液体反应阳性.其变化值用线性回归进行分析.利用受试者工作特征曲线检测其鉴别容量反应性的能力.结果 扩容后ScvO2增加值（△ScvO2）与△CI显著相关.5％可作为△ScyO2的阈值去鉴别患者对容量治疗是否有反应,其敏感性是86％,特异性是94％.结论 扩容后ScvO2的变异可以确定容量治疗是否有效,在缺乏有创CI测定时,ScvO2可作为确定液体反应性的一个可选指标.     

Energy expenditure associated with CPAP and T-piece spontaneous ventilatory trials. Changes following prolonged mechanical ventilation

The use of portable metabolic carts to assess energy expenditure (EE) by measuring oxygen consumption (VO2) and carbon dioxide production (VCO2) has recently been applied to patients undergoing weaning from mechanical ventilation. The VO2 and EE can be used to estimate changes in the work of breathing (WOB) associated with different weaning strategies. The purpose of this study was to use VO2 and EE to assess changes in the WOB when assisted mechanical ventilation (AMV) was replaced with two spontaneous ventilatory trial (SVT) techniques: continuous positive airway pressure (CPAP) and T-piece. Nine difficult-to-wean patients were studied during the initial weaning period following 26 +/- 18 days (mean +/- SD) of mechanical ventilatory support. The VO2 and EE during all AMV were 296 +/- 75 ml/min and 2069 +/- 519 kcal/day, respectively. Compared to the baseline AMV levels, during CPAP overall VO2 and EE increased 14 percent and 13 percent, respectively, and during T-piece overall VO2 and EE increased 20 percent and 19 percent, respectively. Respiration rate (f) increased and tidal volume (VT) decreased during both SVTs compared to AMV although no significant change in minute ventilation was seen. The WOB, as judged from changes in VO2, was only 5 percent higher during T-piece compared to CPAP; however, patients tolerated an average of only 141 +/- 45 min on T-piece vs 165 +/- 29 minutes on CPAP. We conclude that during the initial weaning stages in patients who have received prolonged mechanical ventilatory support, the WOB associated with SVTs is increased compared to AMV but that the WOB associated with T-piece is not significantly greater than that for CPAP.     

Is weaning failure caused by low-frequency fatigue of the diaphragm?

Because patients who fail a trial of weaning from mechanical ventilation experience a marked increase in respiratory load, we hypothesized that these patients develop diaphragmatic fatigue. Accordingly, we measured twitch transdiaphragmatic pressure using phrenic nerve stimulation in 11 weaning failure and 8 weaning success patients. Measurements were made before and 30 minutes after spontaneous breathing trials that lasted up to 60 minutes. Twitch transdiaphragmatic pressure was 8.9 +/- 2.2 cm H2O before the trials and 9.4 +/- 2.4 cm H2O after their completion in the weaning failure patients (p = 0.17); the corresponding values in the weaning success patients were 10.3 +/- 1.5 and 11.2 +/- 1.8 cm H2O (p = 0.18). Despite greater load (p = 0.04) and diaphragmatic effort (p = 0.01), the weaning failure patients did not develop low-frequency fatigue probably because of greater recruitment of rib cage and expiratory muscles (p = 0.004) and because clinical signs of distress mandating the reinstitution of mechanical ventilation arose before the development of fatigue. Twitch pressure revealed considerable diaphragmatic weakness in many weaning failure patients. In conclusion, in contrast to our hypothesis, weaning failure was not accompanied by low-frequency fatigue of the diaphragm, although many weaning failure patients displayed diaphragmatic weakness.     

Central venous and mixed venous oxygen saturation in critically ill patients.

BACKGROUND: Although mixed venous O2 saturation (SvO2) accurately indicates the balance of O2 supply/demand and provides an index of tissue oxygenation, the use of a pulmonary artery (PA) catheter is associated with significant costs, risks and complications. Central venous O2 saturation (ScvO2), obtained in a less risky and costly manner, can be an attractive alternative to SvO2. OBJECTIVES: To investigate whether the values of ScvO2 and SvO2 are well correlated and interchangeable in the evaluation of critically ill ICU patients and to create an equation that could estimate SvO2 from ScvO2. METHODS: Sixty-one mechanically ventilated patients were catheterized upon admission and ScvO2 and SvO2 values were simultaneously measured in the lower part of the superior vena cava and PA respectively. RESULTS: SvO2 was 68.6 +/- 1.2% (mean +/- SEM) and ScvO2 was 69.4 +/- 1.1%. The difference is statistically significant (p < 0.03). The correlation coefficient r is 0.945 for the total population, 0.937 and 0.950 in surgical and medical patients, respectively. In 90.2% of patients the difference was <5%. When regression analysis was performed, among 11 models tested, power model [SvO2 = b0(ScvO2)b1] best described the relationship between the two parameters (R2 = 0.917). CONCLUSIONS: ScvO2 and SvO2 are closely related and are interchangeable for the initial evaluation of critically ill patients even if cardiac indices are different. SvO2 can be estimated with great accuracy by ScvO2 in 92% of the patients using a power model.     

Comparison of automated protocol-based versus non-protocol-based physician-directed weaning from mechanical ventilation

Rationale and objectives

In the weaning of patients from mechanical ventilation by gradually reducing pressure support ventilation (PSV), an automated computerized system recently proved to be superior to traditional physician-directed weaning. The aim of this study was to replicate these findings when weaning a broad surgical intensive care unit (ICU) patient population off the ventilator.

Methods and measurements

Sixty patients requiring mechanical ventilation over 24 h were randomized to either automated (n = 30) or physician-directed (n = 30) weaning. The primary endpoint was duration of weaning. Secondary endpoints were duration of mechanical ventilation, length of ICU stay, reintubation rates, and workload for staff.

Results

Weaning duration did not differ significantly between the computer-driven group and the physician-directed group (0.64 vs. 2.33 d, 95%CI: -0.10 to 2.15, p = 0.167). No significant differences were detected for any secondary endpoint except the workload for PSV settings, which was lower in the computer-driven weaning group (0.0 vs. 0.15 settings/h, p < 0.0001). The trial was stopped early because sample size recalculations based on a Pocock design showed it would be pointless to continue.

Conclusions

Computer-driven weaning was not different from traditional physician-directed weaning from mechanical ventilation. Therefore, it cannot be recommended for routine use in a broad surgical ICU patient population.