Airway occlusion pressure at 0.1 s (P0.1) after extubation: an early indicator of postextubation hypercapnic respiratory insufficiency

Objective: To examine variables associated with postextubation respiratory distress in chronic obstructive pulmonary disease (COPD) patients. Design: Prospective, clinical investigation. Setting: Intensive care unit of a university hospital. Patients: Forty COPD patients, considered ready for extubation. Measurements and main results: We recorded, from the digital display of a standard ventilator, breathing frequency (f), tidal volume (VT) and f/VT for the respiratory pattern, airway occlusion pressure at 0.1 s (P0.1) for the respiratory drive and measured blood gases : i) before extubation, following 30 min of a 6 cm H₂O pressure support (PS) ventilation trial, ii) 1 h after extubation, at the 30th min of a face mask 4 cm H₂O PS ventilation trial. According to the weaning outcome, the patients were divided into two groups : respiratory distress, and non-respiratory distress within 72 h of the discontinuation of mechanical ventilation. The respiratory distress was defined as the combination of f more than 25 breaths/min, an increase in PaCO₂ of at least 20 % compared with the value measured after extubation, and pH lower than 7.35. We determined whether those patients who developed respiratory distress after extubation differed from those who did not. Respiratory pattern data and arterial blood gases recorded, either before or after extubation, and P0.1 recorded before extubation, were inadequate to differentiate the two groups. Only P0.1 recorded 1 h after the discontinuation of mechanical ventilation differentiated the patients who developed respiratory distress from those who did not (4.2 ± 0.9 vs 1.8 ± 0.8, p < 0.01). Conclusions: P0.1 recorded after extubation may be a good indicator of postextubation respiratory distress. Measuring P0.1 and/or the analysis of the evolution of this parameter could facilitate decisions during the period following extubation. Received: 23 March 1998 Accepted: 5 October 1998     

气管内插管非计划拔管的护理因素和预后分析

目的探讨非计划拔管成功与失败的相关护理因素及其与预后的相关性 ,寻求改善预后的措施。方法回顾分析近 5年我们医院ICU中机械通气病人发生非计划拔管的护理临床资料。结果 1 6 5 6例机械通气病人中发生非计划拔管 1 1 6例 (7% ) ,病人自行拔管 90例 (77.5 % ) ,意外脱管 2 6例 (2 2 .4 % ) ,其中 6 2例发生在撤机过程中 ,5 4例发生在完全机械通气状况下。非计划拔管组与对照组在年龄、性别、插管途经、原发病情况、APACHEⅡ评分 ,急性呼衰原因和并发脏器衰竭等无显著差异 (P >0 .0 5 )。非计划拔管失败组与成功组和对照组比较 ,机械通气时间、住ICU时间和住院时间明显延长 ,死亡率无显著差异。结论机械通气病人发生非计划拔管可延长机械通气时间、住ICU时间和住院的时间 ,但不增加死亡率。拔管成功与否取决于拔管当时病人的通气状况。而护理人员对机械通气的病人更需要持续严密监护 ,并帮助病人提高对撤机拔管的认识     

Delay of extubation in neonates and children after cardiac surgery: impact of ventilator-associated pneumonia

Objective: This study was undertaken to determine the delay of extubation attributable to ventilator-associated pneumonia (VAP) in comparison to other complications and complexity of surgery after repair of congenital heart lesions in neonates and children.¶Methods: Cohort study in a pediatric intensive care unit of a tertiary referral center. All patients who had cardiac operations during a 22-month period and who survived surgery were eligible (n = 272, median age 1.3 years). Primary outcome was time to successful extubation. Primary variable of interest was VAP. Surgical procedures were classified according to complexity. Cox proportional hazards models were calculated to adjust for confounding. Potential confounders comprised other known risk factors for delayed extubation.¶Results: Median time to extubation was 3 days. VAP occurred in 26 patients (9.6 %). The rate of VAP was not associated with complexity of surgery (P = 0.22), or cardiopulmonary bypass (P = 0.23). The adjusted analysis revealed as further factors associated with delayed extubation: other respiratory complications (n = 28, chylothorax, airway stenosis, diaphragm paresis), prolonged inotropic support (n = 48, 17.6 %), and the need for secondary surgery (n = 51, 18.8 %; e. g., re-operation, secondary closure of thorax). Older age promoted early extubation. The median delay of extubation attributable to VAP was 3.7 days (hazards ratio HR = 0.29, 95 % CI 0.18–0.49), exceeding the effect size of secondary surgery (HR = 0.48) and other respiratory complications (HR = 0.50).¶Conclusion: VAP accounts for a major delay of extubation in pediatric cardiac surgery.     

预防早产儿拔管失败：加温湿化高流量鼻导管通气与经鼻持续气道正压通气效果比较的Meta分析

目的系统评价加温湿化高流量鼻导管通气(HHHFNC)和经鼻持续气道正压通气(NCPAP)措施预防早产儿拔管失败的有效性和安全性。 方法计算机检索PubMed、Embase、Cochrane Library等英文数据库,以及万方数据知识服务平台、维普中文科技期刊数据库及中国知网(CNKI)等中文数据库中,关于比较HHHFNC与NCPAP预防早产儿拔管失败疗效的随机对照试验(RCT)研究文献,对HHHFNC组与NCPAP组早产儿分别采用HHHFNC、NCPAP模式治疗。文献检索时间设定为2000年1月1日至2018年7月31日。由2位研究者按照本研究设定的文献纳入和排除标准独立筛选文献,评价纳入文献的质量并提取资料,采用Stata 12.0软件对HHHFNC与NCPAP预防早产儿拔管失败的有效性和安全性进行Meta分析。HHHFNC与NCPAP预防早产儿拔管失败的有效性和安全性的主要结局评价指标包括：有效性指标(治疗失败率、再插管率)与安全性指标(鼻损伤、气漏发生率);次要结局评价指标包括：院内死亡率,支气管肺发育不良(BPD)、坏死性小肠结肠炎(NEC)、动脉导管未闭(PDA)、脑室内出血(IVH)、早产儿视网膜病(ROP)等并发症发生率,以及达到全肠道喂养时间。 结果通过文献筛选,并追踪检索已获取全文的相关参考文献,共计8篇RCT研究文献符合本研究纳入、排除标准,纳入的早产儿为1 037例,其中HHHFNC组为518例,NCPAP组为519例。①针对HHHFNC与NCPAP预防早产儿拔管失败的主要结局评价指标的Meta分析结果显示,有效性指标方面,2组早产儿治疗失败率和再插管率比较,差异均无统计学意义(OR＝1.18、0.93,95%CI：0.87～1.59、0.67～1.30,P＝0.286、0.687);而安全性指标方面,HHHFNC组鼻损伤与气漏发生率,则均低于NCPAP组,差异均有统计学意义(OR＝0.17、0.24,95%CI：0.11～0.26、0.09～0.63,P<0.001、＝0.003)。②针对HHHFNC与NCPAP预防早产儿拔管失败的次要结局评价指标的Meta分析结果显示,2组早产儿院内死亡率(OR＝0.93,95%CI：0.40～2.13,P＝0.857),BPD发生率(OR＝0.82,95%CI：0.66～1.11,P＝0.202),IVH发生率(OR＝0.76,95%CI：0.46～1.27,P＝0.299),ROP发生率(OR＝1.09,95%CI：0.69～1.73,P＝0.713),PDA发生率(OR＝0.89,95%CI：0.62～1.28,P＝0.524)及达到全肠道喂养时间(SMD＝0.47,95%CI：－0.35～1.29,P＝0.264)比较,差异均无统计学意义(P>0.05),而HHHFNC组早产儿NEC发生率显著低于NCPAP组,并且差异有统计学意义(OR＝0.56,95%CI：0.33～0.95,P＝0.032)。 结论HHHFNC与NCPAP相比,在预防早产儿拔管失败方面,有效性相似,而前者导致的鼻损伤、气漏和NEC发生率更低,安全性更高。但是,推荐HHHFNC模式作为预防早产儿拔管失败的首选无创通气模式仍然需谨慎。     

Semi-continuous versus injectate cardiac output measurement in intensive care patients after cardiac surgery

Objective Commercially available semi-continuous cardiac output (SCCO) monitoring systems are based on the pulsed warm thermodilution technique. There is evidence that SCCO fails to correlate with standard intermittent bolus cardiac output (ICO) in clinical situations with thermal instability in the pulmonary artery. Furthermore, ventilation may potentially influence thermodilution measurements by enhanced respiratory variations in pulmonary artery blood temperature and by cyclic changes in venous return. Therefore, we evaluated the correlation, accuracy and precision of SCCO versus ICO measurements before and after extubation.Design Prospective cohort study.Setting Intensive care unit (ICU) of a university hospital.Patients and participants 22 cardiac surgical ICU patients.Interventions None.Measurements and results SCCO and ICO data were obtained at nine postoperative time points while the patients were on controlled mechanical ventilation. Further sets of measurements were taken during the weaning phase 20 min before extubation, and 5 min, 20 min and 1 h after extubation. SCCO and ICO measurements yielded 286 data pairs with a range of 1.8–9.9 l/min for SCCO and 1.9–9.8 l/min for ICO. The correlation between SCCO and ICO was highly significant (r=0.92;p<0.01), accompanied by a bias of –0.052 l/min and a precision of 0.56 l/min. Correlation, accuracy and precision were not influenced by the mode of respiration.Conclusions Our results demonstrate excellent correlation, accuracy and precision between SCCO and ICO measurements in postoperative cardiac surgical ICU patients. We conclude that SCCO monitoring offers a reliable clinical method of cardiac ouput monitoring in ICU patients following cardiac surgery.     

ICU患者意外拔管的原因分析与防范措施

目的分析我科(ICU)置管患者意外拔管的原因并提出有效的防范措施。方法我科2010年1月至2011年12月对260例ICU置管患者的临床资料进行回顾性分析。结果发生意外拔管有12例次,因护理安全风险评估及护理措施不到位,而拔管的有10例次,占83.3%;因医护人员操作中缺乏对管路的保护和重视,而拔管的2例次,占16.6%。结论发现意外拔管与患者不适、未进行有效的肢体约束和健康宣教及护理不到位等有关,加强与患者的沟通,做好心理护理,提高其舒适护理,同时对其采取有效的肢体约束,规范操作程序,正确可靠的固定、适度镇静这些都是预防意外拔管的预防措施。     

The Role of Non-invasive Ventilation and Factors Predicting Extubation Outcome in Myasthenic Crisis

Introduction  Myasthenic crisis is a great threat to patients with myasthenia gravis. Usage of non-invasive ventilation (NIV) to prevent intubation and timing of extubating of patients in myasthenic crisis are important issues though not well documented. Methods  To explore the factors predicting NIV success and extubation outcome in myasthenic crisis, we reviewed the records of 41 episodes of myasthenia crisis. Results  NIV was applied to 14 episodes of myasthenic crisis and eight (57.1%) of them were successfully prevented from intubation. An Acute Physiology and Chronic Health Evaluation (APACHE) II score of <6 and a serum bicarbonate level of <30 mmol/l were independent predictors of NIV success. For patients undergoing invasive mechanical ventilation, extubation failure was observed in 13 (39.4%) of 33 episodes, and the most common cause was sputum impaction due to a poor cough strength (61.5%). A maximal expiratory pressure (Pemax) of ≥40 cmH₂O was a good predictor of extubation success. Extubation failure led to poorer outcomes. Conclusions  NIV may be applied to those patients with a low APACHE II score and a lesser degree of metabolic compensation for respiratory acidosis. For patients undergoing invasive mechanical ventilation, extubation failure is associated with significant in-hospital morbidity in myasthenic crisis. Adequate levels of Pemax and cough strength correlate significantly with extubation success.     

先天性心脏病伴重度肺动脉高压体外循环术后拔管时机探讨

目的探讨先天性心脏病（CHD）伴重度肺动脉高压（PH）体外循环（CPB）术后的拔管时机。方法对行CPB手术的40例CHD伴重度PH患者的临床资料进行回顾性分析,按术后机械通气时间是否〉24h,分为早期拔管组（19例）和延迟拔管组（21例）,比较两组影响拔管的围手术期因素。行多因素Logistic回归分析确定延迟拔管（机械通气时间≥72h）的影响因素。结果两组术前NYHA心功能分级、撤机后肺循环与体循环收缩压比值（Pp／Ps）、CPB时间、CPB温度比较差异有统计学意义（P〈0．05或〈0．01）。术后早期缺氧发作（OR=0．022,95％CI0．001～0．580）和严重低氧血症（OR=0．031,95％CI0．002～0．568）是延迟拔管的独立危险因素。结论CHD伴重度PH患者若术前NYHA心功能分级≥Ⅲ级、撤机后Pp／Ps〉0．5、CPB时间〉90min或CPB温度〈32℃,可考虑延迟拔管。对术后早期有缺氧发作或严重低氧血症者,宜延迟拔管并加强心功能和肺动脉压监测;对无上述情况且术后心肺功能稳定者可考虑早期拔管。     

A 2-minute pre-extubation protocol for ventilated intensive care unit patients

Background

Clinicians often are challenged with safely predicting the optimal time of extubation for ventilated patients. Commonly used weaning parameters have poor positive predictive value for successful extubation.

Methods

A total of 213 intubated patients in our 20-bed surgical intensive care unit were enrolled in a trial to test a prospective, observational, 2-minute extubation protocol (TMEP). Daily measurements were obtained on all intubated patients who met criteria, which included adequate oxygenation, systolic blood pressure, heart rate, hemoglobin, Glasgow Coma Score greater than 10t, absence of significant metabolic/respiratory acidosis, and absence of therapeutic or neurologic paralysis. During TMEP, endotracheally intubated patients were physically disconnected from the ventilator for a 2-minute period of observation while spontaneously breathing room air. Patients were extubated if they tolerated the trial without clinically significant desaturation or alteration of vital signs or mental status.

Results

The TMEP reliably predicted successful extubations in 203 of 213 patients (95.3%). Patients who required reintubation had a longer intensive care unit stay and a longer hospital stay.

Conclusions

TMEP is a simple and reliable method of predicting successful extubation.     

脱机拔管后呼吸衰竭患者序贯经鼻高流量湿化氧疗失败的危险因素分析

目的分析拔管后仍存在呼吸衰竭的患者序贯经鼻高流量湿化氧疗（HFNC）失败率及其危险因素。 方法回顾性分析2017年1月1日至2019年3月31日入住福建省立医院ICU气管插管拔管后行序贯HFNC的145例患者。根据HFNC成功与否将其分为HFNC成功组（113例）和HFNC失败组（32例）。比较两组患者的临床资料及实验室指标,并采用Logistic回归分析探究HFNC治疗失败的独立危险因素。 结果HFNC成功组和HFNC失败组患者插管原因（χ² = 11.224,P = 0.024）、慢性心力衰竭（χ² = 4.863,P = 0.027）、心脏瓣膜病（χ² = 6.435,P = 0.011）、呼吸道病原学阳性（χ² = 8.909,P = 0.003）,拔管当天序贯器官衰竭估计评分（Z = 2.138,P = 0.032）、急性病生理学和长期健康评价Ⅱ评分（t = 2.307,P = 0.023）,插管期间使用血管活性药物（χ² = 4.153,P = 0.042）和雾化N-乙酰半胱氨酸（χ² = 4.531,P = 0.033）,拔管前2 d内中性粒细胞计数（t = 2.170,P = 0.032）、淋巴细胞总数<0.8 × 10⁹/L（χ² = 5.941,P = 0.024）、降钙素原（Z = 2.656,P = 0.008）比较,差异均有统计学意义。多因素Logistic回归分析结果显示,拔管前2 d内外周血淋巴细胞总数<0.8 × 10⁹/L[比值比（OR）= 2.898,95%置信区间（CI）（1.059,7.935）,P = 0.038]和呼吸道病原学阳性[OR = 4.617,95%CI（1.463,14.568）,P = 0.009]为HFNC失败的独立危险因素。 结论拔管前2 d内外周血淋巴细胞计数<0.8 × 10⁹/L和呼吸道病原体阳性为气管插管拔管后仍存在呼吸衰竭的患者序贯HFNC失败的独立危险因素。