压力调节容量控制通气方式对急性呼吸衰竭患者气道压力的影响

目的　观察压力调节容量控制 (PRVC)通气模式对气道压力等的影响 ,探讨其在预防气压伤发生中的作用。方法　 2 0 0 1- 0 1～ 2 0 0 2 - 0 5 12例严重急性呼吸衰竭 (ARF)患者机械通气治疗中采用自身对照方法观察PRVC和容量控制(VC)两种通气模式对呼吸力学指标吸气峰压 (PIP)、气道平均压 (MeanAP)和循环、血气等指标的影响 ,除了PRVC和VC模式不同外 ,其余呼吸机参数设置均相同。结果　PRVC组PIP值显著低于VC组 [(19 9± 3 35 )cmH2 Ovs(2 4 8± 2 39)cmH2 O ,t=6 788,P <0 0 5 ],而MeanAP值两组间比较无显著差异 [(10 2± 2 4 9)cmH2 Ovs(10 9± 2 33)cmH2 O ,t=1 4 13,P >0 0 5 ];循环功能和血气各指标两组间比较亦无显著差异 (t=0 2 74～ 2 199,P均 >0 0 5 )。结论　PRVC应用于严重ARF患者正压机械通气治疗时较VC模式可明显降低PIP ,因而是一种肺保护性通气策略 ,可能在防止肺气压伤的发生中发挥有利作用。     

多发伤者急性呼吸衰竭的抢救（附34例分析）

目的通过对严重多发创伤患者的病例分析,指出重视临床早期判断急性呼吸功能障碍和急性呼吸衰竭的重要性,并提出延时使用呼吸机对呼吸衰竭的抢救。方法分析３４例多发伤引起的急性呼吸衰竭者。结果７９４％患者使用呼吸机。其中,Ⅰ型呼吸衰竭者以延时使用为主,占８０％（１２／１５）;Ⅱ型呼吸衰竭者以即刻使用为主,占５８３％（７／１２）。呼吸监测指标（Ｓｐｏ２、呼吸频率及ＥＴｃｏ２）：入院时即刻使用呼吸机者与延时使用呼吸机者相比、延时使用呼吸机者出现急性呼吸衰竭时与入院时相比,都有显著意义（Ｐ＜００１）。结论多发伤者在呼吸监测过程中,若未出现急性呼吸衰竭的状况,无需过早使用机械通气手段。合并有颅脑外伤的多发伤者,其Ⅱ型呼吸衰竭的发生率较高,且多数要依靠即时的机械通气;在胸外伤合并其它外伤和非颅脑、非胸外伤的多发伤患者中,延时使用呼吸机者占很大比率（７３３％）,应引起重视     

Rhabdomyolysis associated with acute renal failure in patients with severe acute respiratory syndrome

An outbreak of severe acute respiratory syndrome (SARS) occurred in Taiwan in 2003. SARS complicated with rhabdomyolysis has rarely been reported. This study reported three cases of rhabdomyolysis developing during the clinical course of SARS. Thirty probable SARS patients were admitted to the isolation wards at Linkou Chang Gung Memorial Hospital between 4 April and 4 June 2003. Thirty patients, including four men and 26 women aged from 12 to 87 years (mean age 40). Eleven (36.7%) patients had respiratory failure and required mechanical ventilation with paralytic therapy; three (10%) patients had rhabdomyolysis complicated with acute renal failure and one received haemodialysis; four (13.3%) patients died. Three cases with rhabdomyolysis all received sedative and paralytic therapy for mechanical ventilation. Haemodialysis was performed on one patient. Two patients died from multiple organ failure, and one patient fully recovered from rhabdomyolysis with acute renal failure. SARS is a serious respiratory illness, and its aetiology is a novel coronavirus. Rhabdomyolysis resulting from SARS virus infection was strongly suspected. Immobilisation under paralytic therapy and steroids may also be important in developing rhabdomyolysis.     

High-frequency percussive ventilation improves oxygenation and ventilation in pediatric patients with acute respiratory failure

Purpose

High-frequency percussive ventilation (HFPV) in pediatrics has been described predominantly in burned patients. We aimed to describe its effectiveness and safety in noninhalational pediatric acute respiratory failure (ARF).

Methods

We conducted an observational study in a tertiary care pediatric intensive care unit on 31 patients with ARF failing conventional ventilation transitioned to HFPV. Demographics, ventilator settings, oxygenation index, oxygen saturation index, oxygen saturation as measured by pulse oximetry/fraction of inspired oxygen (Fio₂), and Pao₂/Fio₂ were recorded before and during HFPV.

Results

Initiation of HFPV was associated with improvements in oxygenation index, oxygen saturation index, Pao₂/Fio₂, and oxygen saturation as measured by pulse oximetry/Fio₂ as early as 12 hours (P < .05), which continued through 48 hours after transition. Improved oxygenation occurred without an increase in mean airway pressures. Reductions in Paco₂ occurred 6 hours after initiation of HFPV and continued through 48 hours (P < .01). Improved gas exchange was accompanied by reduced peak-inflating pressures at all time intervals after initiation of HPFV (P < .01). Vasopressor scores were similar before and after initiation of HFPV in patients requiring vasoactive support. Twenty-six (83.9%) of 31 patients survived to hospital discharge.

Conclusions

In a heterogeneous population of pediatric ARF failing conventional ventilation, HFPV efficiently improves gas exchange in a lung-protective manner.     

Value of static pulmonary compliance in predicting mortality in patients with acute respiratory failure

The measurement of static pulmonary compliance by means of pressure-volume curves is an useful tool in the management of patients with acute respiratory failure. On admission to our Intensive Care Unit, we calculated the static pulmonary compliance values from the pressure-volume curve in 55 severe acute respiratory failure patients under mechanical ventilation. A predictive model, based on static pulmonary compliance measured on the deflation of the pressure-volume curve and patients' age, was developed using a function derived by stepwise discriminant analysis. Thirty-six of the 40 patients (90%) in the learning sample and 12 of the 15 patients (80%) in the test sample were correctly classified into survivors or non-survivors. The overall classification demonstrated an accuracy of 88% (48 of 55 patients). We conclude that the value of static pulmonary compliance can be an useful prognostic factor in patients with severe acute respiratory failure.     

经鼻高流量氧疗对急性呼吸衰竭患者的序贯治疗

目的探讨经鼻高流量氧疗（HFNC）用于急性呼吸衰竭患者序贯治疗的临床效果。 方法选取2016年1月至2017年12月因急性呼吸衰竭入住南通大学附属医院重症医学科行有创机械通气的患者,在撤离呼吸机拔除气管插管后仍存在低氧状态者入选本研究。随机分为对照组44例,高流量组45例。对照组给予常规氧疗方式（鼻导管、面罩）,高流量组则采用经鼻高流量氧疗。比较2组患者拔除气管插管后1、8、24 h的呼吸频率、氧合指数（PaO₂/FiO₂）、动脉血氧饱和度（SaO₂）、二氧化碳分压（PaCO₂）;比较2组患者拔除气管插管后氧疗舒适度、耐受性,无创机械通气使用率,48 h再插管率的差异。 结果高流量组患者的呼吸频率低于对照组,差异具有统计学意义［1 h：（20.6±3.2）次/分 vs （24.5±3.7）次/分;8 h：（21.5±3.6）次/分 vs （20.6±3.2）次/分;24 h：（20.9±3.4）次/分 vs （24.9±4.2）次/分,均P<0.05］,PaO₂/FiO₂及SaO₂高于对照组,差异具有统计学意义［PaO₂/FiO₂：1 h：（241.5±32.6） mmHg vs （213.5±30.7）mmHg;8 h：（252.5±28.6）mmHg vs （228.1±30.7）mmHg;24 h：（261.5±32.6）mmHg vs （230.5±30.7）mmHg;SaO₂：1 h：（96.7±3.6）% vs （92.6±4.3）%;8 h：（96.3±3.8）% vs （93.2±4.3）%;24 h：（96.4±3.6）% vs （93.3±3.9）%;均P<0.05］,舒适度和耐受性优于对照组,差异具有统计学意义［（4.1±0.4）分 vs （3.1±0.4）分;（3.0±0.3）分 vs （1.4±0.3）分,均P<0.05］,无创机械通气率低于对照组,差异具有统计学意义（24.4% vs 45.4%,P<0.05）,2组患者48 h再插管率比较,差异无统计学意义（11.1% vs 13.6%,P>0.05）。 结论经高流量氧疗可更好地改善急性呼吸衰竭患者气管插管拔除后的低氧状态,且有更好的舒适度和耐受性,并能降低患者无创机械通气使用率,可用于急性呼吸衰竭患者拔除气管插管后的序贯治疗。     

Noninvasive ventilation in the event of acute respiratory failure in patients with idiopathic pulmonary fibrosis

Background

Some patients with idiopathic pulmonary fibrosis (IPF) develop severe acute respiratory failure (ARF) requiring admission to an intensive care unit (ICU) and ventilatory support. A limited number of observational studies have reported that noninvasive ventilation (NIV) can be an effective treatment to support breathing and to prevent use of invasive mechanical ventilation in these patients. This study aimed to retrospectively investigate the clinical status and outcomes in IPF patients receiving NIV for ARF and to identify those clinical and laboratory characteristics, which could be considered risk factors for its failure.

Methods

This is a retrospective analysis of short-term outcomes in 18 IPF patients being administered NIV for ARF. This study was conducted in a 4-bed respiratory ICU (RICU) in a university hospital. Eighteen IPF patients who were administered NIV between January 1, 2005, and April 30, 2013, were included. The outcome measures are the need for endotracheal intubation despite NIV treatment and mortality rate during their RICU stay. The length of the patients' stay in the RICU and their survival rate following RICU admission were also evaluated.

Results

Noninvasive ventilation was successful in 8 patients and unsuccessful in 10 who required endotracheal intubation. All the patients in the NIV failure group died within 20.2 ± 15.3 days of intubation. The patients in the NIV success group spent fewer days in the RICU (11.6 ± 4.5 vs 24.6 ± 13.7; P = .0146). The median survival time was significantly shorter for the patients in the NIV failure with respect to the success group (18.0 [95% confidence interval {CI}, 9.0-25.0] vs 90.0 [95% CI, 65.0-305.0] days; P < .0001); the survival rate at 90 days was, likewise, lower in the NIV failure group (0% vs 34% ± 19.5%). At admission, the patients in the failure group had significantly higher respiratory rate values (36.9 ± 7.8 vs 30.5 ± 3.3 breaths/min; P = .036), plasma N-terminal fragment of the prohormone of B-type natriuretic peptide (NT-proBNP) levels (4528.8 ± 4012.8 vs 634.6 ± 808.0 pg/mL; P = .023) and serum C-reactive protein values (72.0 ± 50.0 vs 20.7 ± 24.0 μg/mL; P = .0289) with respect to those in the success group. Noninvasive ventilation failure was correlated to the plasma NT-proBNP levels at RICU admission (P = .0326) with an odds ratio of 12.2 (95% CI, 1.2 to infinity) in the patients with abnormally high values (>900 pg/mL).

Conclusions

The outcome of IPF patients who were administered NIV was quite poor. The use of NIV was, nevertheless, found to be associated with clinical benefits in selected IPF patients, preventing the need for intubation and reducing the rate of complications/death. Elevated plasma NT-proBNP levels at the time of ICU admission is a simple clinical marker for poor NIV outcome.     

Noninvasive continuous positive airway pressure delivered by helmet in hematological malignancy patients with hypoxemic acute respiratory failure

Objective To compare the efficacy of early administration of noninvasive continuous positive airway pressure (nCPAP) delivered by the helmet vs. face mask to treat hematological malignancy patients with fever, pulmonary infiltrates, and hypoxemic acute respiratory failure.Design and setting Prospective clinical study with historical matched controls in the hematology department of a university hospital.Patients and interventions Seventeen hematological malignancy patients with hypoxemic acute respiratory failure defined as: moderate to severe dyspnea, tachypnea (>30–35 breaths/min), use of accessory muscles and paradoxical abdominal motion, and PaO₂/FIO₂ ratio less than 200. Each patient was treated with nCPAP by helmet outside the ICU in the hematological ward. Arterial oxygen saturation, heart rate, respiratory rate, and blood pressure were monitored to identify early nCPAP failure. Seventeen historical-matched controls treated in the same department with face mask CPAP were selected as control population; matching criteria were age, sex, diagnosis, and PaO₂/FIO₂ ratio. Primary end-points were improvement in gas exchanges and the need for endotracheal intubation.Results Oxygenation improved in all patients after nCPAP. No patient failed helmet nCPAP because of intolerance while eigh patients in the mask group did so. nCPAP could be applied continuously for a longer period of time in the helmet group (28.44±0.20 vs. 7.5±0.45 h).Conclusions Early nCPAP with helmet improves oxygenation in selected immunosuppressed patients with hypoxemic acute respiratory failure. Tolerance of helmet nCPAP seems better than that of nCPAP delivered by mask.     

Histologic aspects of pulmonary barotrauma in critically ill patients with acute respiratory failure

Objective To describe histologically pulmonary barotrauma in mechanically ventilated patients with severe acute respiratory failure.Design Assessment of histologic pulmonary barotrauma.Setting A 14-bed surgical intensive care unit (SICU).Patients The lungs of 30 young critically ill patients (mean age 34±10 years) were histologically examined in the immediate post-mortem period. None of them were suspected of pre-existing emphysema.Measurements and results Clinical events and ventilatory settings used during mechanical ventilation were compared with lung histology. Airspace enlargement, defined as the presence of either alveolar overdistension in aerated lung areas or intraparenchymal pseudocysts in nonaerated lung areas, was found in 26 of the 30 lungs examined (86%). Patients with severe airspace enlargement (2.6–40 mm internal diameter) had a significantly greater incidence of pneumothorax (8 versus 2,p<0.05), were ventilated using higher peak airway pressures (56±18 cmH₂O versus 44±10 cmH₂O,p<0.05) and tidal volumes (12±3 ml/kg, versus 9±2ml/kg,p<0.05) were exposed significantly longer to toxic levels of oxygen (8.6±9.4 days versus 1.9±2 days at FIO₂>0.6,p<0.05) and lost more weight (6.3±9.2 kg versus 0.75±5.8 kg,p<0.05) than patients with mild airspace enlargement (1–2.5 mm internal diameter).Conclusion Underlying histologic lesions responsible for clinical lung barotrauma consist of pleural cysts, bronchiolar dilatation, alveolar overdistension and intraparenchymal pseudocysts. Mechanical ventilation appears to be an aggravating factor, particularly when high peak airway pressures and large tidal volumes are delivered by the ventilator.Presented in part at the 32ème Congrès de la Société Française d'Anesthésie-Réanimation, Septembre 1990, Paris, France     

Submersion and acute respiratory failure

ObjectiveTo know the relationship between hypothermia, etiology, respiratory failure and prognosis of submersion in environmental emergency medicine.MethodsFrom December 1, 2002 to September 30, 2007, there were 52 hospitalized near- drowning cases in a medical center at northern Taiwan. Retrospective study of 52 submersion patients who were hospitalized during the duration was analyzed.ResultsThe hypothermic groups are more commonly seen in acute respiratory failure after submersion, 36% vs . 21%, P<0.05. The hypothermic submersion patients who are older in age than normothermic submersion patients (44 vs. 27 years old, P<0.05). The suicidal submersion patients are older, hypothermic and longer length of stay than accidental submersion patients.ConclusionsSubmersion patients who are hypothermic on arrival of emergency department (ED) are risky to respiratory failure and older, more hypothermic, longer hospital stay in suicidal submersion patients.     

Noninvasive ventilation for the treatment of acute respiratory failure in patients with hematologic malignancies: a pilot study

Objective: To evaluate treatment with noninvasive ventilation (NIV) by nasal mask as an alternative to endotracheal intubation and conventional mechanical ventilation in patients with hematologic malignancies complicated by acute respiratory failure to decrease the risk of hemorrhagic complications and increase clinical tolerance. Design: Prospective clinical study. Setting: Hematologic and general intensive care unit (ICU), University of Rome “La Sapienza”. Patients: 16 consecutive patients with acute respiratory failure complicating hematologic malignancies. Interventions: NIV was delivered via nasal mask by means of a BiPAP ventilator (Respironics, USA); we evaluated the effects on blood gases, respiratory rate, and hemodynamics along with tolerance, complications, and outcome. Measurements and results: 15 of the 16 patients showed a significant improvement in blood gases and respiratory rate within the first 24 h of treatment. Arterial oxygen tension (PaO₂), PaO₂/FIO₂ (fractional inspired oxygen) ratio, and arterial oxygen saturation significantly improved after 1 h of treatment (43 ± 10 vs 88 ± 37 mmHg; 87 ± 22 vs 175 ± 64; 81 ± 9 vs 95 ± 4 %, respectively) and continued to improve in the following 24 h (p < 0.01). Five patients died in the ICU following complications independent of the respiratory failure, while 11 were discharged from the ICU in stable condition after a mean stay of 4.3 ± 2.4 days and were discharged in good condition from the hospital. Conclusions: NIV by nasal mask proved to be feasible and appropriate for the treatment of respiratory failure in hematologic patients who were at high risk of intubation – related complications. Received: 21 April 1998 Accepted: 18 September 1998     

影响慢性阻塞性肺疾病急性呼吸衰竭患者预后相关因素研究

目的 探讨影响ICU中慢性阻塞性肺疾病(COPD)急性呼吸衰竭患者预后的相关因素.方法回顾性分析2005年5月至2007年5月因COPD急性加重39例患者的临床资料,分析不同预后患者各指标的差异.结果死亡组患者肺动脉压、肌酐、APACHE Ⅱ评分、APACHE一Ⅲ评分等升高(均P<0.05),ICU住院时间延长(P<0.05);呼吸频率和格拉斯哥昏迷评分下降(P<0.05).结论肺动脉压、肌酐、APACHEⅡ评分、APACHEⅢ评分、呼吸频率和GCS可以预测慢性阻塞性肺疾病急性呼吸衰竭患者的预后.     

无创正压通气治疗急性呼吸衰竭失败原因的分析

目的 探讨应用无创正压通气(NPPV)治疗急性呼吸衰竭失败的相关因素,为临床合理应用提供依据.方法 经NPPV治疗92例患者分为成功组和失败组,监测生命体征和动脉血气分析,记录NPPV通气时间和ICU住院时间,观察NPPV对不同病因引致呼吸衰竭的效果,NPPV治疗2 h的生理指标反应.基础疾病采用急性生理与慢性健康状况评分Ⅱ(APACHEⅡ),意识改变采用Glasgow昏迷评分(GCS).结果 成功组和失败组NPPV时间和ICU住院时间分别为(2±1.6)d和(5±3.4)d、(19±8.7)d和 (8±2.6)d.COPD和急性心源性肺水肿NPPV治疗效果明显,而ARDS和重症肺炎效果差.2 h NPPV通气后,成功组的血气指标明显改善,失败组无明显变化.结论 NPPV治疗呼吸衰竭有重要价值,失败组APACHEⅡ评分明显高于成功组,提示失败组多合并多器官功能不全,严重影响患者的预后.应用NPPV治疗ARDS和重症肺炎需谨慎.使用NPPV早期治疗反应非常重要.     

Two cases of acute respiratory failure due to carcinomatous lymphangitis in HIV patients

In HIV-infected patients, acute respiratory failure is usually due to infectious pneumonia. In this report, we describe two cases of acute respiratory failure in HIV patients with clinical presentation suggesting infectious pneumonia. In both cases, the clinical condition deteriorated and death occurred after several days despite therapy. In both cases bronchial biopsies confirmedbronchogenic carcinoma responsible for carcinomatous lymphangitis.     

Postoperative respiratory failure due to acute eosinophilic pneumonia

A non-smoking 63-year-old man developed respiratory failure following surgical repair of a thoracoabdominal aortic aneurysm. He had severe hypoxemia and an elevated minute ventilation requiring prolonged mechanical support. Initial postoperative chest radiographs revealed new, transient, migratory infiltrates, and the patient received broad-spectrum antibiotic therapy. Chest radiographs subsequently demonstrated persistent, diffuse infiltrates, and bronchoalveolar lavage (BAL) analysis demonstrated significant eosinophilia (30%) with no evidence of infection. A diagnosis of acute eosinophilic pneumonia was made, and treatment with intravenous methylprednisolone resulted in rapid clinical improvement, and extubation. Acute eosinophilic pneumonia is not a previously recognized cause of postoperative respiratory failure and prolonged mechanical ventilation. It should be suspected in postoperative patients with unexplained diffuse lung infiltrates and acute respiratory failure.     

Enhanced renal function associated with intermittent mandatory ventilation in acute respiratory failure

In ten patients suffering from acute respiratory failure (ARF) renal function was evaluated during 2-h periods of intermittent mandatory ventilation (IMV) or controlled mechanical ventilation (CMV). Urine flow, osmolal and creatinine clearances were significantly lower during CMV in comparison to both IMV phases and the free water clearance was less negative. Potassium excretion declined with CMV but remained reduced during the second IMV phase. There was no change in sodium excretion. This study suggests that in order to maintain renal function and prevent water retention the use of IMV should be considered whenever a sufficient mechanical reserve for partial spontaneous ventilation is present.Nomenclature CMV controlled mechanical ventilation - IMV intermittent mechanical ventilation or intermittent mandatory ventilation - IPPB intermittent positive pressure breathing - PEEP positive endexpiratory pressure - F₁O₂ fraction of inspired oxygen - ADH antidiuretic hormone - ARF acute respiratory failure Measurements V urinary output (ml/min) - P osmolarity in the plasma (mosm) - U osmolarity in the urine (mosm) - C creatine Calculations C_osmol osmolal clearance (ml/min) - C_osmol - free water clearance (ml/min) - V–C_osmol (ml/min) - C_creat creatinine clearance (ml/min) - C_creat - U/P ratio U/P This paper is dedicated to Martin Zindler on the occasion of his 60th birthday     

Effect of inspired oxygen fraction on alveolar derecruitment in acute respiratory distress syndrome

Objective High fractions of inspired oxygen (FIO₂) used in acute lung injury (ALI) may promote resorption atelectasis. The impact of derecruitment related to high FIO₂ in ALI is debated. We evaluated derecruitment with 100% vs. 60% FIO₂ at two levels of positive end-expiratory pressure (PEEP).Patients Fourteen consecutive patients with ALI were studied.Interventions Recruited volume at two PEEP levels was computed from two pressure-volume curves, recorded from PEEP and from zero end-expiratory pressure, using the sinusoidal flow modulation method. PEEP-induced recruitment was measured during prolonged expiration as the difference between the two curves at a given pressure. PaO₂/FIO₂ was also measured. PEEP was 5 ± 1 or 14 ± 3 cmH₂O and FIO₂ was 60% or 100%, yielding four combinations. We looked for differences between the beginning and end of a 30-min period with each combination.Measurement and results With low PEEP and 100% FIO₂, recruited volume decreased significantly from 68 ± 53 to 39 ± 43 ml and PaO₂/FIO₂ from 196 ± 104 to 153 ± 83 mmHg. With the three other combinations (low PEEP and 60% FIO₂ or high PEEP and 60% or 100% FIO₂) none of the parameters decreased significantly.Conclusion In mechanically ventilated patients with ALI the breathing of pure oxygen leads to derecruitment, which is prevented by high PEEP.Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users.This article is discussed in the editorial available at:     

Hypophosphatemia and acute respiratory failure in a diabetic patient

A previously healthy 48-year-old male developed diabetic ketoacidosis and severe hypophosphatemia. Within a few hours, acute respiratory insufficiency developed with a marked discrepancy between the pulmonary pathology and the very poor oxygenation seen. We argue that this was due to the effect of hypophosphatemia on respiratory muscle- and heart function and P₅₀, leading to impaired oxygen delivery.