Comparison of the efficacy and safety of FP-1201-lyo (intravenously administered recombinant human interferon beta-1a) and placebo in the treatment of patients with moderate or severe acute respiratory distress syndrome: study protocol for a randomized controlled trial

Background

Acute respiratory distress syndrome (ARDS) results in vascular leakage, inflammation and respiratory failure. There are currently no approved pharmacological treatments for ARDS and standard of care involves treatment of the underlying cause, and supportive care. The vascular leakage may be related to reduced concentrations of local adenosine, which is involved in maintaining endothelial barrier function. Interferon (IFN) beta-1a up-regulates the cell surface ecto-5′-nucleotidase cluster of differentiation 73 (CD73), which increases adenosine levels, and IFN beta-1 may, therefore, be a potential treatment for ARDS. In a phase I/II, open-label study in 37 patients with acute lung injury (ALI)/ARDS, recombinant human IFN beta-1a was well tolerated and mortality rates were significantly lower in treated than in control patients.

Methods/design

In this phase III, double-blind, randomized, parallel-group trial, the efficacy and safety of recombinant human IFN beta-1a (FP-1201-lyo) will be compared with placebo in adult patients with ARDS. Patients will be randomly assigned to receive 10 μg FP-1201-lyo or placebo administered intravenously once daily for 6 days and will be monitored for 28 days or until discharged from the intensive care unit. Follow-up visits will then take place at days 90, 180 and 360. The primary endpoint is a composite endpoint including any cause of death at 28 days and days free of mechanical ventilation within 28 days among survivors. Secondary endpoints include: all-cause mortality at 28, 90, 180 and 360 days; organ failure-free days; length of hospital stay; pharmacodynamic assessment including measurement of myxovirus resistance protein A concentrations; and measures of quality of life, respiratory and neurological function at 180 and 360 days. The estimated sample size to demonstrate a reduction in the primary outcome between groups from 30% to 15% is 300 patients, and the study will be conducted in 70–80 centers in nine countries across Europe.

Discussion

There are no effective specific treatments for patients with ARDS and mortality rates remain high. The results from this study will provide evidence regarding the efficacy of a potential new therapeutic agent, FP-1201-lyo, in improving the clinical course and outcome for patients with moderate/severe ARDS.

Trial registration

European Union Clinical Trials Register, no: 2014-005260-15. Registered on 15 July 2017.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-017-2234-7) contains supplementary material, which is available to authorized users.

The Role of Rescue Therapies in the Treatment of Severe ARDS

ARDS is characterized by a non-cardiogenic pulmonary edema with bilateral chest radiograph opacities and hypoxemia refractory to oxygen therapy. It is a common cause of admission to the ICU due to hypoxemic respiratory failure requiring mechanical ventilation. Corticosteroids are not recommended in ARDS patients. Rescue therapies alleviate hypoxemia in patients unable to maintain reasonable oxygenation: recruitment maneuvers, prone positioning, inhaled nitric oxide, high-frequency oscillatory ventilation, and extracorporeal membrane oxygenation improve oxygenation, but their impact on mortality remains unproven. Restrictive fluid management seems to be a favorable strategy with no significant reduction in 60-d mortality. Future studies are needed to clarify the efficacy of these therapies on outcomes in patients with severe ARDS, and institution of these therapies may be considered on a case-by-case basis.

Respiratory support in patients with acute respiratory distress syndrome: an expert opinion

Acute respiratory distress syndrome (ARDS) is a common condition in intensive care unit patients and remains a major concern, with mortality rates of around 30–45% and considerable long-term morbidity. Respiratory support in these patients must be optimized to ensure adequate gas exchange while minimizing the risks of ventilator-induced lung injury. The aim of this expert opinion document is to review the available clinical evidence related to ventilator support and adjuvant therapies in order to provide evidence-based and experience-based clinical recommendations for the management of patients with ARDS.

Fifty Years of Research in ARDS. Is Extracorporeal Circulation the Future of Acute Respiratory Distress Syndrome Management?

Mechanical ventilation (MV) remains the cornerstone of acute respiratory distress syndrome (ARDS) management. It guarantees sufficient alveolar ventilation, high Fi_O2 concentration, and high positive end-expiratory pressure levels. However, experimental and clinical studies have accumulated, demonstrating that MV also contributes to the high mortality observed in patients with ARDS by creating ventilator-induced lung injury. Under these circumstances, extracorporeal lung support (ECLS) may be beneficial in two distinct clinical settings: to rescue patients from the high risk for death associated with severe hypoxemia, hypercapnia, or both not responding to maximized conventional MV, and to replace MV and minimize/abolish the harmful effects of ventilator-induced lung injury. High extracorporeal blood flow venovenous extracorporeal membrane oxygenation (ECMO) may therefore rescue the sickest patients with ARDS from the high risk for death associated with severe hypoxemia, hypercapnia, or both not responding to maximized conventional MV. Successful venovenous ECMO treatment in patients with extremely severe H1N1-associated ARDS and positive results of the CESAR trial have led to an exponential use of the technology in recent years. Alternatively, lower-flow extracorporeal CO₂ removal devices may be used to reduce the intensity of MV (by reducing Vt from 6 to 3-4 ml/kg) and to minimize or even abolish the harmful effects of ventilator-induced lung injury if used as an alternative to conventional MV in nonintubated, nonsedated, and spontaneously breathing patients. Although conceptually very attractive, the use of ECLS in patients with ARDS remains controversial, and high-quality research is needed to further advance our knowledge in the field.

Physiological Correlation of Airway Pressure and Transpulmonary Pressure Stress Index on Respiratory Mechanics in Acute Respiratory Failure

BACKGROUND

Stress index at post-recruitment maneuvers could be a method of positive end-expiratory pressure (PEEP) titration in acute respiratory distress syndrome (ARDS) patients. However, airway pressure (Paw) stress index may not reflect lung mechanics in the patients with high chest wall elastance. This study was to evaluate the Pawstress index on lung mechanics and the correlation between Pawstress index and transpulmonary pressure (PL) stress index in acute respiratory failure (ARF) patients.

METHODS

Twenty-four ARF patients with mechanical ventilation (MV) were consecutively recruited from July 2011 to April 2013 in Zhongda Hospital, Nanjing, China and Ospedale S. Giovanni Battista-Molinette Hospital, Turin, Italy. All patients underwent MV with volume control (tidal volume 6 ml/kg) for 20 min. PEEP was set according to the ARDSnet study protocol. The patients were divided into two groups according to the chest wall elastance/respiratory system elastance ratio. The high elastance group (H group, n = 14) had a ratio ≥30%, and the low elastance group (L group, n = 10) had a ratio <30%. Respiratory elastance, gas-exchange, Pawstress index, and PLstress index were measured. Student's t-test, regression analysis, and Bland-Altman analysis were used for statistical analysis.

RESULTS

Pneumonia was the major cause of respiratory failure (71.0%). Compared with the L group, PEEP was lower in the H group (5.7 ± 1.7 cmH2O vs. 9.0 ± 2.3 cmH2O, P < 0.01). Compared with the H group, lung elastance was higher (20.0 ± 7.8 cmH2O/L vs. 11.6 ± 3.6 cmH2O/L, P < 0.01), and stress was higher in the L group (7.0 ± 1.9 vs. 4.9 ± 1.9, P = 0.02). A linear relationship was observed between the Pawstress index and the PLstress index in H group (R2 = 0.56, P < 0.01) and L group (R2 = 0.85, P < 0.01).

CONCLUSION

In the ARF patients with MV, Pawstress index can substitute for PLto guide ventilator settings.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02196870 (https://clinicaltrials.gov/ct2/show/NCT02196870).

Extracorporeal carbon dioxide removal (ECCO2R) in patients with acute respiratory failure

PURPOSE

To review the available knowledge related to the use of ECCO₂R as adjuvant strategy to mechanical ventilation (MV) in various clinical settings of acute respiratory failure (ARF).

METHODS

Expert opinion and review of the literature.

RESULTS

ECCO₂R may be a promising adjuvant therapeutic strategy for the management of patients with severe exacerbations of COPD and for the achievement of protective or ultra-protective ventilation in patients with ARDS without life-threatening hypoxemia. Given the observational nature of most of the available clinical data and differences in technical features and performances of current devices, the balance of risks and benefits for or against ECCO₂R in such patient populations remains unclear CONCLUSIONS: ECCO₂R is currently an experimental technique rather than an accepted therapeutic strategy in ARF-its safety and efficacy require confirmation in clinical trials.

Heart rate reduction with esmolol is associated with improved arterial elastance in patients with septic shock: a prospective observational study

PURPOSE

Ventricular-arterial (V-A) decoupling decreases myocardial efficiency and is exacerbated by tachycardia that increases static arterial elastance (Ea). We thus investigated the effects of heart rate (HR) reduction on Ea in septic shock patients using the beta-blocker esmolol. We hypothesized that esmolol improves Ea by positively affecting the tone of arterial vessels and their responsiveness to HR-related changes in stroke volume (SV).

METHODS

After at least 24 h of hemodynamic optimization, 45 septic shock patients, with an HR ≥95 bpm and requiring norepinephrine to maintain mean arterial pressure (MAP) ≥65 mmHg, received a titrated esmolol infusion to maintain HR between 80 and 94 bpm. Ea was calculated as MAP/SV. All measurements, including data from right heart catheterization, echocardiography, arterial waveform analysis, and norepinephrine requirements, were obtained at baseline and at 4 h after commencing esmolol.

RESULTS

Esmolol reduced HR in all patients and this was associated with a decrease in Ea (2.19 ± 0.77 vs. 1.72 ± 0.52 mmHg l(-1)), arterial dP/dt max (1.08 ± 0.32 vs. 0.89 ± 0.29 mmHg ms(-1)), and a parallel increase in SV (48 ± 14 vs. 59 ± 18 ml), all p < 0.05. Cardiac output and ejection fraction remained unchanged, whereas norepinephrine requirements were reduced (0.7 ± 0.7 to 0.58 ± 0.5 µg kg(-1) min(-1), p < 0.05).

CONCLUSIONS

HR reduction with esmolol effectively improved Ea while allowing adequate systemic perfusion in patients with severe septic shock who remained tachycardic despite standard volume resuscitation. As Ea is a major determinant of V-A coupling, its reduction may contribute to improving cardiovascular efficiency in septic shock.

Association between driving pressure and development of postoperative pulmonary complications in patients undergoing mechanical ventilation for general anaesthesia: a meta-analysis of individual patient data

BACKGROUND

Protective mechanical ventilation strategies using low tidal volume or high levels of positive end-expiratory pressure (PEEP) improve outcomes for patients who have had surgery. The role of the driving pressure, which is the difference between the plateau pressure and the level of positive end-expiratory pressure is not known. We investigated the association of tidal volume, the level of PEEP, and driving pressure during intraoperative ventilation with the development of postoperative pulmonary complications.

METHODS

We did a meta-analysis of individual patient data from randomised controlled trials of protective ventilation during general anesthaesia for surgery published up to July 30, 2015. The main outcome was development of postoperative pulmonary complications (postoperative lung injury, pulmonary infection, or barotrauma).

FINDINGS

We included data from 17 randomised controlled trials, including 2250 patients. Multivariate analysis suggested that driving pressure was associated with the development of postoperative pulmonary complications (odds ratio [OR] for one unit increase of driving pressure 1·16, 95% CI 1·13-1·19; p<0·0001), whereas we detected no association for tidal volume (1·05, 0·98-1·13; p=0·179). PEEP did not have a large enough effect in univariate analysis to warrant inclusion in the multivariate analysis. In a mediator analysis, driving pressure was the only significant mediator of the effects of protective ventilation on development of pulmonary complications (p=0·027). In two studies that compared low with high PEEP during low tidal volume ventilation, an increase in the level of PEEP that resulted in an increase in driving pressure was associated with more postoperative pulmonary complications (OR 3·11, 95% CI 1·39-6·96; p=0·006).

INTERPRETATION

In patients having surgery, intraoperative high driving pressure and changes in the level of PEEP that result in an increase of driving pressure are associated with more postoperative pulmonary complications. However, a randomised controlled trial comparing ventilation based on driving pressure with usual care is needed to confirm these findings.

FUNDING

None.

Non-invasive ventilation in patients with hematologic malignancy: a new prospective

Immunosuppressed patients are usually considered together without distinction. However, patients with hematologic malignancy should be included in a different subcategory. The outcome of this population has improved over the years. However, mortality rate continues to be high, especially when respiratory complications are present and mechanical ventilation is required. Non-invasive ventilation (NIV) demonstrated its efficacy on the process of respiratory failure improving clinical outcomes in patients of different diagnoses. Recommendations of guidelines to use NIV in immunosuppressed patients have been quite prudent. However, NIV has been recently applied in hematologic malignancy patients during an early or/and late respiratory failure, showing a favorable impact improving the outcome. At an early stage, one study showed CPAP to reduce respiratory complications and to improve the outcome of mortality rate from 75% in the control group to 15% in the treatment group, when compared to oxygen therapy. In other two randomized control trials, NIV in comparison to invasive mechanical ventilation demonstrated to reduce mortality rate from 100% to 53-61%. As most of the non-randomized control trials applied NIV in a general population of immunosuppressed patients, results are very difficult to analyze. So far, the treatment starting, and duration time are still not clearly defined. Novel clinical trials should be performed to elucidate the appropriate application of NIV in this population.

Lung recruitability is better estimated according to the Berlin definition of acute respiratory distress syndrome at standard 5 cm H2O rather than higher positive end-expiratory pressure: a retrospective cohort study

OBJECTIVES

The Berlin definition of acute respiratory distress syndrome has introduced three classes of severity according to PaO2/FIO2 thresholds. The level of positive end-expiratory pressure applied may greatly affect PaO2/FIO2, thereby masking acute respiratory distress syndrome severity, which should reflect the underlying lung injury (lung edema and recruitability). We hypothesized that the assessment of acute respiratory distress syndrome severity at standardized low positive end-expiratory pressure may improve the association between the underlying lung injury, as detected by CT, and PaO2/FIO2-derived severity.

DESIGN

Retrospective analysis.

SETTING

Four university hospitals (Italy, Germany, and Chile).

PATIENTS

One hundred forty-eight patients with acute lung injury or acute respiratory distress syndrome according to the American-European Consensus Conference criteria.

INTERVENTIONS

Patients underwent a three-step ventilator protocol (at clinical, 5 cm H2O, or 15 cm H2O positive end-expiratory pressure). Whole-lung CT scans were obtained at 5 and 45 cm H2O airway pressure.

MEASUREMENTS AND MAIN RESULTS

Nine patients did not fulfill acute respiratory distress syndrome criteria of the novel Berlin definition. Patients were then classified according to PaO2/FIO2 assessed at clinical, 5 cm H2O, or 15 cm H2O positive end-expiratory pressure. At clinical positive end-expiratory pressure (11±3 cm H2O), patients with severe acute respiratory distress syndrome had a greater lung tissue weight and recruitability than patients with mild or moderate acute respiratory distress syndrome (p<0.001). At 5 cm H2O, 54% of patients with mild acute respiratory distress syndrome at clinical positive end-expiratory pressure were reclassified to either moderate or severe acute respiratory distress syndrome. In these patients, lung recruitability and clinical positive end-expiratory pressure were higher than in patients who remained in the mild subgroup (p<0.05). When patients were classified at 5 cm H2O, but not at clinical or 15 cm H2O, lung recruitability linearly increases with acute respiratory distress syndrome severity (5% [2-12%] vs 12% [7-18%] vs 23% [12-30%], respectively, p<0.001). The potentially recruitable lung was the only CT-derived variable independently associated with ICU mortality (p=0.007).

CONCLUSIONS

The Berlin definition of acute respiratory distress syndrome assessed at 5 cm H2O allows a better evaluation of lung recruitability and edema than at higher positive end-expiratory pressure clinically set.

Perioperative cardiovascular monitoring of high-risk patients: a consensus of 12

A significant number of surgical patients are at risk of intra- or post-operative complications or both, which are associated with increased lengths of stay, costs, and mortality. Reducing these risks is important for the individual patient but also for health-care planners and managers. Insufficient tissue perfusion and cellular oxygenation due to hypovolemia, heart dysfunction or both is one of the leading causes of perioperative complications. Adequate perioperative management guided by effective and timely hemodynamic monitoring can help reduce the risk of complications and thus potentially improve outcomes. In this review, we describe the various available hemodynamic monitoring systems and how they can best be used to guide cardiovascular and fluid management in the perioperative period in high-risk surgical patients.

Clinical impact of stress dose steroids in patients with septic shock: insights from the PROWESS-Shock trial

INTRODUCTION

The aim of our study was to evaluate the clinical impact of the administration of intravenous steroids, alone or in conjunction with drotrecogin-alfa (activated) (DrotAA), on the outcomes in septic shock patients.

METHODS

We performed a sub-study of the PROWESS-Shock trial (septic shock patients who received fluids and vasopressors above a predefined threshold for at least 4 hours were randomized to receive either DrotAA or placebo for 96 hours). A propensity score for the administration of intravenous steroids for septic shock at baseline was constructed using multivariable logistic regression. Cox proportional hazards model using inverse probability of treatment weighting of the propensity score was used to estimate the effect of intravenous steroids, alone or in conjunction with DrotAA, on 28-day and 90-day all-cause mortality.

RESULTS

A total of 1695 patients were enrolled of which 49.5% received intravenous steroids for treatment of septic shock at baseline (DrotAA + steroids N = 436; DrotAA + no steroids N = 414; placebo + steroids N = 403; placebo + no steroids N = 442). The propensity weighted risk of 28-day as well as 90-day mortality in those treated vs. those not treated with steroids did not differ among those randomized to DrotAA vs. placebo (interaction p-value = 0.38 and p = 0.27, respectively) nor was a difference detected within each randomized treatment. Similarly, the course of vasopressor use and cardiovascular SOFA did not appear to be influenced by steroid therapy. In patients with lung infection (N = 744), abdominal infection (N = 510), Gram-positive sepsis (N = 420) and Gram-negative sepsis (N = 461), the propensity weighted risk of 28-day as well as 90-day mortality in those treated vs. those not treated with steroids did not differ among those randomized to DrotAA vs. placebo nor was a difference detected within each randomized treatment.

CONCLUSIONS

In the present study of septic shock patients, after adjustment for treatment selection bias, we were unable to find noticeable positive impact from intravenous steroids for treatment of septic shock at baseline either in patients randomized for DrotAA or placebo.

TRIAL REGISTRATION

Clinicaltrials.gov NCT00604214 . Registered 24 January 2008.

Extracorporeal Co2 removal in hypercapnic patients at risk of noninvasive ventilation failure: a matched cohort study with historical control

OBJECTIVES

To assess efficacy and safety of noninvasive ventilation-plus-extracorporeal Co2 removal in comparison to noninvasive ventilation-only to prevent endotracheal intubation patients with acute hypercapnic respiratory failure at risk of failing noninvasive ventilation.

DESIGN

Matched cohort study with historical control.

SETTING

Two academic Italian ICUs.

PATIENTS

Patients treated with noninvasive ventilation for acute hypercapnic respiratory failure due to exacerbation of chronic obstructive pulmonary disease (May 2011 to November 2013).

INTERVENTIONS

Extracorporeal CO2 removal was added to noninvasive ventilation when noninvasive ventilation was at risk of failure (arterial pH ≤ 7.30 with arterial PCO2 > 20% of baseline, and respiratory rate ≥ 30 breaths/min or use of accessory muscles/paradoxical abdominal movements). The noninvasive ventilation-only group was created applying the genetic matching technique (GenMatch) on a dataset including patients enrolled in two previous studies. Exclusion criteria for both groups were mean arterial pressure less than 60 mm Hg, contraindications to anticoagulation, body weight greater than 120 kg, contraindication to continuation of active treatment, and failure to obtain consent.

MEASUREMENTS AND MAIN RESULTS

Primary endpoint was the cumulative prevalence of endotracheal intubation. Twenty-five patients were included in the noninvasive ventilation-plus-extracorporeal CO2 removal group. The GenMatch identified 21 patients for the noninvasive ventilation-only group. Risk of being intubated was three times higher in patients treated with noninvasive ventilation-only than in patients treated with noninvasive ventilation-plus-extracorporeal CO2 removal (hazard ratio, 0.27; 95% CI, 0.07-0.98; p = 0.047). Intubation rate in noninvasive ventilation-plus-extracorporeal CO2 removal was 12% (95% CI, 2.5-31.2) and in noninvasive ventilation-only was 33% (95% CI, 14.6-57.0), but the difference was not statistically different (p = 0.1495). Thirteen patients (52%) experienced adverse events related to extracorporeal CO2 removal. Bleeding episodes were observed in three patients, and one patient experienced vein perforation. Malfunctioning of the system caused all other adverse events.

CONCLUSIONS

These data provide the rationale for future randomized clinical trials that are required to validate extracorporeal CO2 removal in patients with hypercapnic respiratory failure and respiratory acidosis nonresponsive to noninvasive ventilation.

Respiratory failure due to upper airway obstruction in children: use of the helmet as bridge interface

Upper airway obstruction (UAO) can cause severe respiratory distress in young children by increasing inspiratory muscle load and decreasing alveolar ventilation, ultimately resulting in hypercapnia and hypoxemia which have long term negative cardiovascular effects. Although non-invasive continuous positive airway pressure (CPAP) improves gas exchange in these patients, use of conventional interfaces (nasal mask, nasal pillow and facial mask) may cause significant discomfort and lead to CPAP intolerance. We report five cases of children affected by UAO who experienced CPAP intolerance via application of conventional interfaces. Alternatively, we acutely applied helmet-CPAP which resulted in improved breathing pattern and gas exchange. Thereafter, patients received training with respect to a nasal CPAP interface, allowing successful long term treatment. In conclusion, these five clinical cases demonstrate that helmet-CPAP can be used acutely in children with UAO if compliance to conventional modalities is problematic, allowing for sufficient time to achieve compliance to nasal-CPAP.

Genome-wide association study of survival from sepsis due to pneumonia: an observational cohort study

BACKGROUND

Sepsis continues to be a major cause of death, disability, and health-care expenditure worldwide. Despite evidence suggesting that host genetics can influence sepsis outcomes, no specific loci have yet been convincingly replicated. The aim of this study was to identify genetic variants that influence sepsis survival.

METHODS

We did a genome-wide association study in three independent cohorts of white adult patients admitted to intensive care units with sepsis, severe sepsis, or septic shock (as defined by the International Consensus Criteria) due to pneumonia or intra-abdominal infection (cohorts 1-3, n=2534 patients). The primary outcome was 28 day survival. Results for the cohort of patients with sepsis due to pneumonia were combined in a meta-analysis of 1553 patients from all three cohorts, of whom 359 died within 28 days of admission to the intensive-care unit. The most significantly associated single nucleotide polymorphisms (SNPs) were genotyped in a further 538 white patients with sepsis due to pneumonia (cohort 4), of whom 106 died.

FINDINGS

In the genome-wide meta-analysis of three independent pneumonia cohorts (cohorts 1-3), common variants in the FER gene were strongly associated with survival (p=9·7 × 10(-8)). Further genotyping of the top associated SNP (rs4957796) in the additional cohort (cohort 4) resulted in a combined p value of 5·6 × 10(-8) (odds ratio 0·56, 95% CI 0·45-0·69). In a time-to-event analysis, each allele reduced the mortality over 28 days by 44% (hazard ratio for death 0·56, 95% CI 0·45-0·69; likelihood ratio test p=3·4 × 10(-9), after adjustment for age and stratification by cohort). Mortality was 9·5% in patients carrying the CC genotype, 15·2% in those carrying the TC genotype, and 25·3% in those carrying the TT genotype. No significant genetic associations were identified when patients with sepsis due to pneumonia and intra-abdominal infection were combined.

INTERPRETATION

We have identified common variants in the FER gene that associate with a reduced risk of death from sepsis due to pneumonia. The FER gene and associated molecular pathways are potential novel targets for therapy or prevention and candidates for the development of biomarkers for risk stratification.

FUNDING

European Commission and the Wellcome Trust.

Extracorporeal support for severe acute respiratory failure

Extracorporeal membrane oxygenation (ECMO) and extracorporeal CO(2) removal (ECCO(2)R) techniques have increasingly been applied in patients with severe acute lung injury refractory to conventional mechanical ventilatory support. The objectives of this article are to review current concepts of extracorporeal life support techniques (ECMO and ECCO(2)R systems) and provide the rationale for their application in patients with acute respiratory distress syndrome, chronic obstruction pulmonary disease, and as adjunctive therapy for bridging patients to lung transplantation.

Tracheostomy in mechanical ventilation

Airway access for mechanical ventilation (MV) can be provided either by orotracheal intubation (OTI) or tracheostomy tube. During episodes of acute respiratory failure, patients are commonly ventilated through an orotracheal tube that represents an easy and rapid initial placement of the airway device. OTI avoids acute surgical complications such as bleeding, nerve and posterior tracheal wall injury, and late complications such as wound infection and tracheal lumen stenosis that may emerge due to tracheostomy tube placement. Tracheostomy is often considered when MV is expected to be applied for prolonged periods or for the improvement of respiratory status, as this approach provides airway protection, facilitates access for secretion removal, improves patient comfort, and promotes progression of care in and outside the intensive care unit (ICU). The aim of this review is to assess the frequency and performance of different surgical or percutaneous dilational tracheostomy and timing and safety procedures associated with the use of fiberoptic bronchoscopy and ultrasounds. Moreover, we analyzed the performance based on National European surveys to assess the current tracheostomy practice in ICUs.

The application of esophageal pressure measurement in patients with respiratory failure

This report summarizes current physiological and technical knowledge on esophageal pressure (Pes) measurements in patients receiving mechanical ventilation. The respiratory changes in Pes are representative of changes in pleural pressure. The difference between airway pressure (Paw) and Pes is a valid estimate of transpulmonary pressure. Pes helps determine what fraction of Paw is applied to overcome lung and chest wall elastance. Pes is usually measured via a catheter with an air-filled thin-walled latex balloon inserted nasally or orally. To validate Pes measurement, a dynamic occlusion test measures the ratio of change in Pes to change in Paw during inspiratory efforts against a closed airway. A ratio close to unity indicates that the system provides a valid measurement. Provided transpulmonary pressure is the lung-distending pressure, and that chest wall elastance may vary among individuals, a physiologically based ventilator strategy should take the transpulmonary pressure into account. For monitoring purposes, clinicians rely mostly on Paw and flow waveforms. However, these measurements may mask profound patient-ventilator asynchrony and do not allow respiratory muscle effort assessment. Pes also permits the measurement of transmural vascular pressures during both passive and active breathing. Pes measurements have enhanced our understanding of the pathophysiology of acute lung injury, patient-ventilator interaction, and weaning failure. The use of Pes for positive end-expiratory pressure titration may help improve oxygenation and compliance. Pes measurements make it feasible to individualize the level of muscle effort during mechanical ventilation and weaning. The time is now right to apply the knowledge obtained with Pes to improve the management of critically ill and ventilator-dependent patients.

Pharmacokinetics of anidulafungin in two critically ill patients with septic shock undergoing CVVH

Candidemia is associated with high mortality rate especially in critically ill (ICU) patients with septic shock and echinocandins such as anidulafungin are recommended as first-line treatment. Available pharmacokinetic studies of anidulafungin in healthy volunteers and in patients with renal or hepatic impairment showed that no dose adjustment is needed even in patients receiving standard intermittent haemodialysis. However, few data are available with continuous veno-venous haemofiltration (CVVH). In this study, the pharmacokinetic of anidulafungin was studied in two ICU patients with candidemia and septic shock undergoing CVVH. Both patients had satisfactory parameters of C(max) (9.04 and 5.68 mg/l, respectively), area under the curve (AUC) (95.18 and 67.48 mg/l h) and C(min) (2.61 and 1.43 mg/l). AUC/MIC ratio and C(max)/MIC values were: 11887 and 8435; 1130.25 and 710, for patients 1 and 2, respectively. Our data confirm that in patients with septic shock anidulafungin presents only mild pharmacokinetic changes compared to data reported during CVVH alone.

Epidemiology and outcome of sepsis syndromes in Italian ICUs: a muticentre, observational cohort study in the region of Piedmont

BACKGROUND

Sepsis is an important cause of mortality and morbidity in the intensive care unit (ICU). We performed a study to describe the epidemiology of sepsis syndromes in patients admitted to ICUs of the Piedmont region.

METHODS

In this prospective, multicentre, observational study, all 3902 patients admitted to a network of 24 ICUs from 17 hospitals during a 180 day period (April 3-September 29, 2006) were included. Patients were followed from the first day of admission until death or ICU discharge.

RESULTS

The incidence of sepsis during the ICU stay was 11.4% (N.=446), corresponding to an incidence of 25 cases/100,000 inhabitants/year; 141 (31.6%) patients had only sepsis, 160 patients had severe sepsis (35.9%) and 145 patients (32.5%) had septic shock In 227 patients (50.9%), sepsis was observed within 48 hours after admission to the ICU, and 219 patients (49.1%) developed ICU-acquired sepsis. The main sources of infection were the lungs, abdomen, and urinary tract. ICU mortality was higher (41.3 vs. 17.3%, P<0.0001) and the median ICU length of stay longer (15 vs. 2 days, P<0.0001) in patients with sepsis than in those without sepsis. The mortality rate increased with the severity of sepsis. ICU-acquired sepsis was associated with higher ICU mortality rates than sepsis occurring within 48 hours of ICU admission (49.8 vs. 33.0%, P<0.0001).

CONCLUSION

Sepsis is a common occurrence in critically ill patients. Our data underscore the regional variability in the epidemiology and outcome of sepsis syndromes and may be useful to guide appropriate resource allocation.

Recommendations for anesthesia and perioperative management of patients with neuromuscular disorders

Patients with neuromuscular disorders are at high risk of intraoperative and postoperative complications. General anesthesia in these patients may exacerbate respiratory and cardiovascular failure due to a marked sensitivity to several anesthetic drugs. Moreover, succinylcholine and halogenated agents can trigger life-threatening reactions, such as malignant hyperthermia, rhabdomyolysis and severe hyperkalemia. Therefore, regional anesthesia should be used whenever possible. If general anesthesia is unavoidable, special precautions must be taken. In particular, for patients at increased risk of respiratory complications (i.e., postoperative atelectasis, acute respiratory failure, nosocomial infections), noninvasive ventilation associated with aggressive airway clearance techniques can successfully treat upper airway obstruction, hypoventilation and airway secretion retention, avoiding prolonged intubation and tracheotomy. Anesthesia and perioperative management of patients with neuromuscular disorders are described in this article. To grade the strength of recommendations and the quality of evidence we adopted the GRADE approach. In case of low-quality evidence, these recommendations represent the collective opinion of the expert panel.

Clinical review: Respiratory monitoring in the ICU - a consensus of 16

Monitoring plays an important role in the current management of patients with acute respiratory failure but sometimes lacks definition regarding which 'signals' and 'derived variables' should be prioritized as well as specifics related to timing (continuous versus intermittent) and modality (static versus dynamic). Many new techniques of respiratory monitoring have been made available for clinical use recently, but their place is not always well defined. Appropriate use of available monitoring techniques and correct interpretation of the data provided can help improve our understanding of the disease processes involved and the effects of clinical interventions. In this consensus paper, we provide an overview of the important parameters that can and should be monitored in the critically ill patient with respiratory failure and discuss how the data provided can impact on clinical management.

Predicting mortality risk in patients undergoing venovenous ECMO for ARDS due to influenza A (H1N1) pneumonia: the ECMOnet score

PURPOSE

The decision to start venovenous extracorporeal membrane oxygenation (VV ECMO) is commonly based on the severity of respiratory failure, with little consideration of the extrapulmonary organ function. The aim of the study was to identify predictors of mortality and to develop a score allowing a better stratification of patients at the time of VV ECMO initiation.

METHODS

This was a prospective multicenter cohort study on 60 patients with influenza A (H1N1)-associated respiratory distress syndrome participating in the Italian ECMOnet data set in the 2009 pandemic. Criteria for ECMO institution were standardized according to national guidelines.

RESULTS

The survival rate in patients treated with ECMO was 68 %. Significant predictors of death before ECMO institution by multivariate analysis were hospital length of stay before ECMO institution (OR = 1.52, 95 % CI 1.12-2.07, p = 0.008); bilirubin (OR = 2.32, 95 % CI 1.52-3.52, p < 0.001), creatinine (OR = 7.38, 95 % CI 1.43-38.11, p = 0.02) and hematocrit values (OR = 0.82, 95 % CI 0.72-0.94, p = 0.006); and mean arterial pressure (OR = 0.92, 95 % CI 0.88-0.97, p < 0.001). The ECMOnet score was developed based on these variables, with a score of 4.5 being the most appropriate cutoff for mortality risk prediction. The high accuracy of the ECMOnet score was further confirmed by ROC analysis (c = 0.857, 95 % CI 0.754-0.959, p < 0.001) and by an independent external validation analysis (c = 0.694, 95 % CI 0.562-0.826, p = 0.004).

CONCLUSIONS

Mortality risk for patients receiving VV ECMO is correlated to the extrapulmonary organ function at the time of ECMO initiation. The ECMOnet score is a tool for the evaluation of the appropriateness and timing of VV ECMO in acute lung failure.

Patterns and early evolution of organ failure in the intensive care unit and their relation to outcome

INTRODUCTION

Recognition of patterns of organ failure may be useful in characterizing the clinical course of critically ill patients. We investigated the patterns of early changes in organ dysfunction/failure in intensive care unit (ICU) patients and their relation to outcome.

METHODS

Using the database from a large prospective European study, we studied 2,933 patients who had stayed more than 48 hours in the ICU and described patterns of organ failure and their relation to outcome. Patients were divided into three groups: patients without sepsis, patients in whom sepsis was diagnosed within the first 48 hours after ICU admission, and patients in whom sepsis developed more than 48 hours after admission. Organ dysfunction was assessed by using the sequential organ failure assessment (SOFA) score.

RESULTS

A total of 2,110 patients (72% of the study population) had organ failure at some point during their ICU stay. Patients who exhibited an improvement in organ function in the first 24 hours after admission to the ICU had lower ICU and hospital mortality rates compared with those who had unchanged or increased SOFA scores (12.4 and 18.4% versus 19.6 and 24.5%, P < 0.05, pairwise). As expected, organ failure was more common in sepsis than in nonsepsis patients. In patients with single-organ failure, in-hospital mortality was greater in sepsis than in nonsepsis patients. However, in patients with multiorgan failure, mortality rates were similar regardless of the presence of sepsis. Irrespective of the presence of sepsis, delta SOFA scores over the first 4 days in the ICU were higher in nonsurvivors than in survivors and decreased significantly over time in survivors.

CONCLUSIONS

Early changes in organ function are strongly related to outcome. In patients with single-organ failure, in-hospital mortality was higher in sepsis than in nonsepsis patients. However, in multiorgan failure, mortality rates were not influenced by the presence of sepsis.

CXCL10-CXCR3 enhances the development of neutrophil-mediated fulminant lung injury of viral and nonviral origin

RATIONALE

Patients who developed acute respiratory distress syndrome (ARDS) after infection with severe respiratory viruses (e.g., severe acute respiratory syndrome-coronavirus, H5N1 avian influenza virus), exhibited unusually high levels of CXCL10, which belongs to the non-ELR (glutamic-leucine-arginine) CXC chemokine superfamily. CXCL10 may not be a bystander to the severe virus infection but may directly contribute to the pathogenesis of neutrophil-mediated, excessive pulmonary inflammation.

OBJECTIVES

We investigated the contribution of CXCL10 and its receptor CXCR3 axis to the pathogenesis of ARDS with nonviral and viral origins.

METHODS

We induced nonviral ARDS by acid aspiration and viral ARDS by intratracheal influenza virus infection in wild-type mice and mice deficient in CXCL10, CXCR3, IFNAR1 (IFN-α/β receptor 1), or TIR domain-containing adaptor inducing IFN-β (TRIF).

MEASUREMENTS AND MAIN RESULTS

We found that the mice lacking CXCL10 or CXCR3 demonstrated improved severity and survival of nonviral and viral ARDS, whereas mice that lack IFNAR1 did not control the severity of ARDS in vivo. The increased levels of CXCL10 in lungs with ARDS originate to a large extent from infiltrated pulmonary neutrophils, which express a unique CXCR3 receptor via TRIF. CXCL10-CXCR3 acts in an autocrine fashion on the oxidative burst and chemotaxis in the inflamed neutrophils, leading to fulminant pulmonary inflammation.

CONCLUSIONS

CXCL10-CXCR3 signaling appears to be a critical factor for the exacerbation of the pathology of ARDS. Thus, the CXCL10-CXCR3 axis could represent a prime therapeutic target in the treatment of the acute phase of ARDS of nonviral and viral origins.

Being overweight or obese is associated with decreased mortality in critically ill patients: a retrospective analysis of a large regional Italian multicenter cohort

PURPOSE

To describe the epidemiology of obesity in a large cohort of intensive care unit (ICU) patients and study its impact on outcomes.

METHODS

All 3902 patients admitted to one of 24 ICUs in the Piedmont region of Italy from April 3 to September 29, 2006, were included in this retrospective analysis of data from a prospective, multicenter study.

RESULTS

Mean body mass index (BMI) was 26.0 ± 5.4 kg/m(2): 32.8% of patients had a normal BMI, 2.6% were underweight, 45.1% overweight, 16.5% obese, and 2.9% morbidly obese. ICU mortality was significantly (P < .05) lower in overweight (18.8%) and obese (17.5%) patients than in those of normal BMI (22%). In multivariate logistic regression analysis, being overweight (OR = 0.73; 95%CI: 0.58-0.91, P = .007) or obese (OR = 0.62; 95%CI: 50.45-0.85, P = .003) was associated with a reduced risk of ICU death. Being morbidly obese was independently associated with an increased risk of death in elective surgery patients whereas being underweight was independently associated with an increased risk of death in patients admitted for short-term monitoring and after elective surgery.

CONCLUSIONS

In this cohort, overweight and obese patients had a reduced risk of ICU death. Being underweight or morbidly obese was associated with an increased risk of death in some subgroups of patients.

What's new in the "Berlin" definition of acute respiratory distress syndrome?

A valid operative definition for ARDS is essential for the appropriate institution of a standardized 'best-evidence' treatment and for the identification of subgroups of patients who may benefit from specific adjunctive interventions, as well as to assist with prognostication, resource allocation and the design of new research trials. Here, we will discuss some of the methodology used by the ARDS Definition Task Force to develop the new 'Berlin' definition of ARDS, briefly discussing the rationale for the divergence from the AECC definition. The Berlin definition improves on the predictive validity for mortality of the American-European Consensus Conference's (AECC) definition and clarifies both the conceptual model of ARDS and the definition criteria of the syndrome and of its spectrum of severity. This should facilitate case recognition and more consistent treatment strategies based on severity.

Noninvasive method for measuring respiratory system compliance during pressure support ventilation

PURPOSE

To date, few methods have been accepted for assessing the respiratory system compliance (C(rs)) in patients under assisted ventilation at the bedside. The aim of this study was to evaluate our adaptive time slice method (ATSM) to continuously calculate the C(rs).

METHODS

One breath is divided into several time periods (slices). For each slice, a compliance value C(i) is calculated. The slice width is adapted according to the confidence interval of C(i). After all C(i) values are obtained and the outliers are eliminated, the C(rs) of this breath is calculated as the mean value of the remainder of C(i)'s. Seven patients with Chronic Obstructive Pulmonary Disease were evaluated during pressure support ventilation. The results are compared with the values calculated with the transdiaphragmatic pressure (P(di)).

RESULTS

95 ± 4% of the recorded data could be analyzed with ATSM. In 6 patients out of 7, the results delivered with ATSM and with P(di) had similar variation (standard deviation) and accuracy (difference<20%). They were strongly correlated (weighted correlation coefficient = 0.86, p<10(-5)) with a mean difference of 3.22 ml/mbar.

CONCLUSIONS

The ATSM is a robust method and able to provide accurate C(rs) in spontaneously breathing patients during pressure support ventilation noninvasively without extra instrumentation or complicated maneuvers.