Safety and efficacy of noninvasive ventilation in patients with blunt chest trauma: a systematic review

Introduction

This systematic review looks at the use of noninvasive ventilation (NIV), inclusive of noninvasive positive pressure ventilation (NPPV) and continuous positive pressure ventilation (CPAP), in patients with chest trauma to determine its safety and clinical efficacy in patients with blunt chest trauma who are at high risk of acute lung injury (ALI) and respiratory failure.

Methods

We searched the MEDLINE, EMBASE and Cochrane Central Register of Controlled Trials (CENTRAL) databases. Pairs of reviewers abstracted relevant clinical data and assessed the methodological quality of randomized controlled trials (RCTs) using the Cochrane domain and observational studies using the Newcastle-Ottawa Scale.

Results

Nine studies were included (three RCTs, two retrospective cohort studies and four observational studies without a comparison group). There was significant heterogeneity among the included studies regarding the severity of injuries, degree of hypoxemia and timing of enrollment. One RCT of moderate quality assessed the use of NPPV early in the disease process before the development of respiratory distress. All others evaluated the use of NPPV and CPAP in patients with blunt chest trauma after the development of respiratory distress. Overall, up to 18% of patients enrolled in the NIV group needed intubation. The duration of NIV use was highly variable, but NIV use itself was not associated with significant morbidity or mortality. Four low-quality observational studies compared NIV to invasive mechanical ventilation in patients with respiratory distress and showed decreased ICU stay (5.3 to 16 days vs 9.5 to 15 days), complications (0% to 18% vs 38% to 49%) and mortality (0% to 9% vs 6% to 50%) in the NIV group.

Conclusions

Early use of NIV in appropriately identified patients with chest trauma and without respiratory distress may prevent intubation and decrease complications and ICU length of stay. Use of NIV to prevent intubation in patients with chest trauma who have ALI associated with respiratory distress remains controversial because of the lack of good-quality data.     

Impact of the humidification device on intubation rate during noninvasive ventilation with ICU ventilators: results of a multicenter randomized controlled trial

Purpose

The use of heat and moisture exchangers (HME) during noninvasive ventilation (NIV) can increase the work of breathing, decrease alveolar ventilation, and deliver less humidity in comparison with heated humidifiers (HH). We tested the hypothesis that the use of HH during NIV with ICU ventilators for patients with acute respiratory failure would decrease the rate of intubation (primary endpoint) as compared with HME.

Methods

We conducted a multicenter randomized controlled study in 15 centers. After stratification by center and type of respiratory failure (hypoxemic or hypercapnic), eligible patients were randomized to receive NIV with HH or HME.

Results

Of the 247 patients included, 128 patients were allocated to the HME group and 119 to the HH group. Patients were comparable at baseline. The intubation rate was not significantly different: 29.7 % in the HME group and 36.9 % in the HH group (p = 0.28). PaCO₂ did not significantly differ between the two arms, even in the subgroup of hypercapnic patients. No significant difference was observed for NIV duration, ICU and hospital LOS, or ICU mortality (HME 14.1 vs. HH 21.5 %, p = 0.18).

Conclusions

In this study, the short-term physiological benefits of HH in comparison with HME during NIV with ICU ventilators were not observed, and no difference in intubation rate was found. The physiologic effects may have been obscured by leaks or other important factors in the clinical settings. This study does not support the recent recommendation favoring the use of HH during NIV with ICU ventilators.     

Assessment of heart rate,acidosis, consciousness,oxygenation, and respiratory rate to predict noninvasive ventilation failure in hypoxemic patients

Purpose

To develop and validate a scale using variables easily obtained at the bedside for prediction of failure of noninvasive ventilation (NIV) in hypoxemic patients.

Methods

The test cohort comprised 449 patients with hypoxemia who were receiving NIV. This cohort was used to develop a scale that considers heart rate, acidosis, consciousness, oxygenation, and respiratory rate (referred to as the HACOR scale) to predict NIV failure, defined as need for intubation after NIV intervention. The highest possible score was 25 points. To validate the scale, a separate group of 358 hypoxemic patients were enrolled in the validation cohort.

Results

The failure rate of NIV was 47.8 and 39.4% in the test and validation cohorts, respectively. In the test cohort, patients with NIV failure had higher HACOR scores at initiation and after 1, 12, 24, and 48 h of NIV than those with successful NIV. At 1 h of NIV the area under the receiver operating characteristic curve was 0.88, showing good predictive power for NIV failure. Using 5 points as the cutoff value, the sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy for NIV failure were 72.6, 90.2, 87.2, 78.1, and 81.8%, respectively. These results were confirmed in the validation cohort. Moreover, the diagnostic accuracy for NIV failure exceeded 80% in subgroups classified by diagnosis, age, or disease severity and also at 1, 12, 24, and 48 h of NIV. Among patients with NIV failure with a HACOR score of >5 at 1 h of NIV, hospital mortality was lower in those who received intubation at ≤12 h of NIV than in those intubated later [58/88 (66%) vs. 138/175 (79%); p = 0.03).

Conclusions

The HACOR scale variables are easily obtained at the bedside. The scale appears to be an effective way of predicting NIV failure in hypoxemic patients. Early intubation in high-risk patients may reduce hospital mortality.

     

Noninvasive mechanical ventilation in patients having declined tracheal intubation

Purpose

Noninvasive ventilation (NIV) is a treatment option in patients with acute respiratory failure who are good candidates for intensive care but have declined tracheal intubation. The aim of our study was to report outcomes after NIV in patients with a do-not-intubate (DNI) order.

Methods

Prospective observational cohort study in all patients who received NIV for acute respiratory failure in 54 ICUs in France and Belgium, in 2010/2011.

Results

Goals of care, comfort, and vital status were assessed daily. On day 90, a telephone interview with patients and relatives recorded health-related quality of life (HRQOL), posttraumatic stress disorder-related symptoms, and symptoms of anxiety and depression. Post-ICU burden was compared between DNI patients and patients receiving NIV with no treatment-limitation decisions (TLD). Of 780 NIV patients, 574 received NIV with no TLD, and 134 had DNI orders. Hospital mortality was 44 % in DNI patients and 12 % in the no-TLD group. Mortality in the DNI group was lowest in COPD patients compared to other patients in the DNI group (34 vs. 51 %, P = 0.01). In the DNI group, HRQOL showed no significant decline on day 90 compared to baseline; day-90 data of patients and relatives did not differ from those in the no-TLD group.

Conclusions

Do-not-intubate status was present among one-fifth of ICU patients who received NIV. DNI patients who were alive on day 90 experienced no decrease in HRQOL compared to baseline. The prevalences of anxiety, depression, and PTSD-related symptoms in these patients and their relatives were similar to those seen after NIV was used as part of full-code management (clinicaltrial.govNCT01449331).     

Apnoeic oxygenation via high-flow nasal cannula oxygen combined with non-invasive ventilation preoxygenation for intubation in hypoxaemic patients in the intensive care unit: the single-centre,blinded, randomised controlled OPTINIV trial

Purpose

High-flow nasal cannula oxygen (HFNC) has the potential to provide apnoeic oxygenation. We decided to assess in a proof-of-concept study whether the addition of HFNC to non-invasive ventilation (NIV) could reduce oxygen desaturation during intubation, compared with NIV alone for preoxygenation, in severely hypoxaemic intensive care unit (ICU) patients with respiratory failure.

Methods

We conducted a randomised, controlled, single-centre trial with assessor-blinded outcome assessment in patients admitted to the ICU. Hypoxaemic patients requiring orotracheal intubation for respiratory failure were randomised to receive preoxygenation using HFNC [flow = 60 L/min, fraction of inspired oxygen (FiO₂) = 100 %] combined with NIV (pressure support = 10 cmH₂O, positive end-expiratory pressure = 5 cmH₂O, FiO₂ = 100 %) in the intervention group or NIV alone in the reference group prior to intubation. The primary outcome was the lowest oxygen saturation (SpO₂) during the intubation procedure. Secondary outcomes were intubation-related complications and ICU mortality.

Results

Between July 2015 and February 2016, we randomly assigned 25 and 24 patients to the intervention and reference groups, respectively. In both groups the main reasons for respiratory failure were pneumonia and ARDS. During the intubation procedure, the lowest SpO₂ values were significantly higher in the intervention group than in the reference group [100 (95–100) % vs. 96 (92–99) %, p = 0.029]. After exclusion of two patients from analysis for protocol violation, no (0 %) patients in the intervention group and five (21 %) patients in the reference group had SpO₂ below 80 % (p = 0.050). We recorded no significant difference between the groups in intubation-related complications or ICU mortality.

Conclusions

A novel strategy for preoxygenation in hypoxaemic patients, adding HFNC for apnoeic oxygenation to NIV prior to orotracheal intubation, may be more effective in reducing the severity of oxygen desaturation than the reference method using NIV alone.

     

Early postoperative prophylactic noninvasive ventilation after major lung resection in COPD patients: a randomized controlled trial

Objectives

To investigate whether prophylactic postoperative NIV prevents respiratory complications following lung resection surgery in COPD patients.

Methods

In seven thoracic surgery departments, 360 COPD patients undergoing lung resection surgery were randomly assigned to two groups: conventional postoperative treatment without (n = 179) or with (n = 181) prophylactic NIV, applied intermittently during 6 h per day for 48 h following surgery. The primary endpoint was the rate of acute respiratory events (ARE) at 30 days postoperatively (ITT analysis). Secondary endpoints were acute respiratory failure (ARF), intubation rate, mortality rate, infectious and non-infectious complications, and duration of ICU and hospital stay.

Measurements and main results

ARE rates did not differ between the prophylactic NIV and control groups (57/181, 31.5 vs. 55/179, 30.7 %, p = 0.93). ARF rate was 18.8 % in the prophylactic NIV group and 24.5 % in controls (p = 0.20). Re-intubation rates were similar in the prophylactic NIV and control group [10/181 (5.5 %) and 13/179 (7.2 %), respectively, p = 0.53]. Mortality rates were 5 and 2.2 % in the control and prophylactic NIV groups, respectively (p = 0.16). Infectious and non-infectious complication rates, and duration of ICU and hospital stays were similar between groups.

Conclusions

Prophylactic postoperative NIV did not reduce the rate of ARE in COPD patients undergoing lung resection surgery and did not influence other postoperative complications rates, mortality rates, and duration of ICU and hospital stay.     

Intermittent noninvasive ventilation after extubation in patients with chronic respiratory disorders: a multicenter randomized controlled trial (VHYPER)

Purpose

Early noninvasive ventilation (NIV) after extubation decreases the risk of respiratory failure and lowers 90-day mortality in patients with hypercapnia. Patients with chronic respiratory disease are at risk of extubation failure. Therefore, it could be useful to determine the role of NIV with a discontinuous approach, not limited to patients with hypercapnia. We assessed the efficacy of early NIV in decreasing respiratory failure after extubation in patients with chronic respiratory disorders.

Methods

A prospective randomized controlled multicenter study was conducted. We enrolled 144 mechanically ventilated patients with chronic respiratory disorders who tolerated a spontaneous breathing trial. Patients were randomly allocated after extubation to receive either NIV (NIV group, n = 72), performed with a discontinuous approach, for the first 48 h, or conventional oxygen treatment (usual care group, n = 72). The primary endpoint was decreased respiratory failure within 48 h after extubation. Analysis was by intention to treat. This trial was registered with ClinicalTrials.gov (NCT01047852).

Results

Respiratory failure after extubation was less frequent in the NIV group: 6 (8.5%) versus 20 (27.8%); p = 0.0016. Six patients (8.5%) in the NIV group versus 13 (18.1%) in the usual care group were reintubated; p = 0.09. Intensive care unit (ICU) mortality and 90-day mortality did not differ significantly between the two groups (p = 0.28 and p = 0.33, respectively). Median postrandomization ICU length of stay was lower in the usual care group: 3 days (IQR 2–6) versus 4 days (IQR 2–7; p = 0.008). Patients with hypercapnia during a spontaneous breathing trial were at risk of developing postextubation respiratory failure [adjusted odds ratio (95% CI) = 4.56 (1.59–14.00); p = 0.006] and being intubated [adjusted odds ratio (95% CI) = 3.60 (1.07–13.31); p = 0.04].

Conclusions

Early NIV performed following a sequential protocol for the first 48 h after extubation decreased the risk of respiratory failure in patients with chronic respiratory disorders. Reintubation and mortality did not differ between NIV and conventional oxygen therapy.

     

Small dead space heat and moisture exchangers do not impede gas exchange during noninvasive ventilation: a comparison with a heated humidifier

Objective

Adverse respiratory and gasometrical effects have been described in patients with acute respiratory failure (ARF) undergoing noninvasive ventilation (NIV) with standard heat and moisture exchangers (HME). We decided to evaluate respiratory parameters and arterial blood gases (ABG) of patients during NIV with small dead space HME compared with heated humidifier (HH).

Design

Prospective randomized crossover study.

Setting

A 16-bed medical intensive care unit (ICU).

Patients

Fifty patients receiving NIV for ARF.

Measurements

The effects of HME and HH on respiratory rate, minute ventilation, EtCO₂, oxygen saturation, airway occlusion pressure at 0.1 s, ABG, and comfort perception were compared during two randomly determined NIV periods of 30 min. The relative impact of HME and HH on these parameters was successively compared with or without addition of a flex tube (40 and 10 patients, respectively).

Main results

No difference was observed between HME and HH regarding any of the studied parameters, whether or not a flex tube was added.

Conclusion

If one decides to humidify patients’ airways during NIV, one may do so with small dead space HME or HH without altering respiratory parameters.     

Predicting non-invasive ventilation failure in children from the SpO2/FiO2 (SF) ratio

Purpose

Our objective was to assess whether SpO₂/FiO₂ (SF) ratio could be a useful NIV outcome predictor in children with acute respiratory failure (ARF) and tried to develop a predictive model of NIV failure.

Methods

Prospective, observational, multicenter study. Episodes of ARF-fulfilling inclusion criteria from 15 January 2010 to 14 January 2011 were treated with NIV according to a pre-established protocol. Clinical variables were collected at baseline and at 1, 2, 6, 12 and 24 h. Failure criterion was the need for endotracheal intubation. Failures were considered as “early” if occurring ≤6 h after NIV initiation, “intermediate” if occurring between 6 and 24 h, and “late” if occurring after 24 h. Variables with a p < 0.1 in univariate analysis corrected by age were included in multivariate analysis. Models were calculated based on multivariate analysis.

Results

During the study period, 390 episodes were included. NIV success rate was 81.3 %. Among ARF causes, failure occurred most frequently in ARDS episodes. The failure predictive model for the whole sample included SF ratio at 1 h, age and PRISM III-24 (area under the curve AUC of 0.755). For early NIV failures, SF ratio at 1 h was the only variable within model (AUC 0.748). The analysis of intermediate NIV failures identified 3 variables independently linked to NIV outcome: PRISM III-24, RR decrease at 6 h, and SF ratio at 6 h (AUC 0.895). No model was identified for late NIV failure.

Conclusions

SF ratio is a reliable predictor of early NIV failure in children.     

Non-invasive ventilation as a strategy for weaning from invasive mechanical ventilation: a systematic review and Bayesian meta-analysis

Purpose

A systematic review and meta-analysis was conducted to answer the question ‘In adults with respiratory failure requiring invasive ventilation for more than 24 h, does a weaning strategy with early extubation to non-invasive ventilation (NIV) compared to invasive ventilation weaning reduce all-cause hospital mortality?’

Methods

We included randomised and quasi-randomised controlled trials that evaluated the use of non-invasive ventilation, compared to invasive ventilation, as a weaning strategy in adults mechanically ventilated for at least 24 h. The EMBASE, MEDLINE and Cochrane Central Register of Controlled Trials (CENTRAL) bibliographic databases were searched from inception to February 2018. Bayesian hierarchical models were used to perform the meta-analysis. The primary outcome was mortality at hospital discharge. Secondary outcomes included mortality (30, 60, 90 and 180 days), quality of life, duration of invasive ventilation, weaning failure, length of stay [intensive care unit (ICU) and hospital] and adverse events.

Results

Twenty-five relevant studies involving 1609 patients were included in the quantitative analysis. Studies had moderate to high risk of bias due to risk of performance and detection bias. Mortality at hospital discharge was lower in the NIV weaning group compared to the invasive weaning group [pooled odds ratio (OR) 0.58, 95% highest density interval (HDI) 0.29–0.89]. Subgroup analyses showed lower pooled mortality at hospital discharge rates in NIV weaning than those in the control group in chronic obstructive pulmonary disease (COPD) patients (pooled OR 0.43, 95% HDI 0.13–0.81) and the effect is less certain in the mixed ICU population (pooled OR 0.88, 95% HDI 0.25–1.48). NIV weaning reduced the duration of invasive ventilation in patients [standardised mean difference (SMD) ??1.34, 95% HDI ??1.92 to ??0.77] and ICU length of stay (SMD ??0.70, 95% HDI ??0.94 to ??0.46). Reported rates of ventilator associated pneumonia (VAP) were lower in the NIV group. NIV weaning did not reduce overall hospital length of stay or long-term mortality. There were insufficient data to compare other adverse events and health-related quality of life.

Conclusions

The use of NIV in weaning from mechanical ventilation decreases hospital mortality, the incidence of VAP and ICU length of stay. NIV as a weaning strategy appears to be most beneficial in patients with COPD.

     

Increase in use of non-invasive ventilation for infants with severe bronchiolitis is associated with decline in intubation rates over a decade

Purpose

To redress the paucity of studies evaluating non-invasive respiratory support in bronchiolitis patients.

Methods

Following ethics committee approval, the clinical database of a tertiary 23-bed paediatric intensive care unit (PICU) was reviewed for bronchiolitis admissions from January 2000 to December 2009. Length of stay (LOS), ventilatory requirements and risk factors, including prematurity, respiratory syncytial virus (RSV) status, chronic lung, neuromuscular, immune and congenital heart disease, were analysed.

Results

Of 8,288 admissions, 520 (6.27?%) had bronchiolitis with 343 (65.9?%) having RSV. Median (±SD) age and LOS were 2.78?months and 2.68 (±4.32)?days. One (0.2?%) patient died. Assisted ventilation was required for 399 (76.7?%) patients. A total of 114 (28.6?%) patients were intubated directly and 285 (71.4?%) had a trial of non-invasive ventilation (NIV). Significant increase in the use of NIV was seen (2.8?%/year) with decline in intubation rates (1.9?%/ year) (p?=?0.002). Of NIV patients, 237 (83.2?%) needed only NIV and 48 (16.8?%) failed and therefore needed intubation. The median LOS was shorter in those who succeeded NIV (2.38?±?2.43?days) compared to those with invasive ventilation (5.19?±?6.34?days) and those who failed NIV (8.41?±?3.44?days). Presence of a risk factor increased the chances of failing NIV from 6 to 10?%.

Conclusion

NIV was successful in the vast majority of patients, particularly in those without risk factors and halved the LOS in intensive care. Failure of NIV was associated with increased duration of invasive ventilation and PICU LOS. A prospective study comparing different techniques of NIV will be helpful in defining the risks of failure of NIV.     

Automatic adjustment of pressure support by a computer-driven knowledge-based system during noninvasive ventilation: a feasibility study

Objective

To evaluate the feasibility of using a knowledge-based system designed to automatically titrate pressure support (PS) to maintain the patient in a “respiratory comfort zone” during noninvasive ventilation (NIV) in patients with acute respiratory failure.

Design and setting

Prospective crossover interventional study in an intensive care unit of a university hospital.

Patients

Twenty patients.

Interventions

After initial NIV setting and startup in conventional PS by the chest physiotherapist NIV was continued for 45?min with the automated PS activated.

Measurements and results

During automated PS minute-volume was maintained constant while respiratory rate decreased significantly from its pre-NIV value (20?±?3 vs. 25?±?3?bpm). There was a trend towards a progressive lowering of dyspnea. In hypercapnic patients PaCO₂ decreased significantly from 61?±?9 to 51?±?2?mmHg, and pH increased significantly from 7.31?±?0.05 to 7.35?±?0.03. Automated PS was well tolerated. Two system malfunctions occurred prompting physiotherapist intervention.

Conclusions

The results of this feasibility study suggest that the system can be used during NIV in patients with acute respiratory failure. Further studies should now determine whether it can improve patient-ventilator interaction and reduce caregiver workload.

     

Early intermittent noninvasive ventilation for acute chest syndrome in adults with sickle cell disease: a pilot study

Purpose

Alveolar hypoxia and hypoxic vasoconstriction lead to trapping of sickle cells within the pulmonary vasculature. Improving alveolar ventilation and oxygenation may improve the outcome of acute chest syndrome (ACS).

Methods

Prospective randomized single-center open study from November 1998 to February 2002 to test whether noninvasive ventilation (NIV) was more effective than oxygen alone in improving oxygenation on day 3 in adults with ACS and to evaluate the effects on pain, transfusion requirements, and length of stay.

Results

Seventy-one consecutive ACS episodes in 67 patients were randomly allocated to oxygen (n = 36) or NIV (n = 35) for 3 days in a medical step-down unit. Baseline respiratory rate and pain score were higher in the NIV group. NIV promptly lowered the respiratory rate, raised $ {\text{Pa}}_{{\text{O}_{2}}} $ , and decreased alveolar–arterial oxygen gradient $ (({\text{A}} - {\text{a}})_{{{\text{O}}_{ 2} }} ) $ , which remained unchanged with oxygen alone. $ {\text{Pa}}_{{{\text{CO}}_{ 2} }} $ significantly worsened only in the oxygen group. On day 3, the groups did not differ regarding the proportion of episodes with normal $ {\text{Pa}}_{{{\text{O}}_{ 2} }} $ (35% with NIV and 25% with oxygen; P = 0.5) or $ (({\text{A}} - {\text{a}})_{{{\text{O}}_{ 2} }} ) $ . Patient satisfaction and compliance were lower with NIV. No differences were noted in pain relief, transfusions, or length of stay. In the subgroup of patients with severe hypoxemia $ ( {\text{Pa}}_{{{\text{O}}_{ 2} }} \le 6 5\,{\text{mmHg)}} $ , physiological variables also improved faster with NIV, the differences being slightly more pronounced.

Conclusions

Respiratory rate and gas exchange improved faster with NIV. However, NIV failed to significantly reduce the number of patients remaining hypoxemic at day 3, and was associated with greater patient discomfort.     

The feasibility and safety of extracorporeal carbon dioxide removal to avoid intubation in patients with COPD unresponsive to noninvasive ventilation for acute hypercapnic respiratory failure (ECLAIR study): multicentre case–control study

Introduction

The aim of the study was to evaluate the feasibility and safety of avoiding invasive mechanical ventilation (IMV) by using extracorporeal CO₂ removal (ECCO₂R) in patients with acute exacerbation of chronic obstructive pulmonary disease (COPD) and acute hypercapnic respiratory failure refractory to noninvasive ventilation (NIV).

Methods

Case–control study. Patients with acute hypercapnic respiratory failure refractory to NIV being treated with a pump-driven veno-venous ECCO₂R system (iLA-Activve^®; Novalung, Heilbronn, Germany) were prospectively observed in five European intensive care units (ICU). Inclusion criteria were respiratory acidosis (pH ≤ 7.35, PaCO₂ > 45 mmHg) with predefined criteria for endotracheal intubation (ClinicalTrials.gov NCT01784367). The historical controls were patients with acute hypercapnic respiratory failure refractory to NIV who were treated with IMV. The matching criteria were main diagnosis, age, SAPS-II score and pH.

Results

Twenty-five cases (48.0 % male, mean age 67.3 years) were matched with 25 controls. Intubation was avoided in 14 patients (56.0 %) in the ECCO₂R group with a mean extracorporeal blood flow of 1.3 L/min. Seven patients were intubated because of progressive hypoxaemia and four owing to ventilatory failure despite ECCO₂R and NIV. Relevant ECCO₂R-associated adverse events were observed in 11 patients (44.0 %), of whom 9 (36.0 %) suffered major bleeding complications. The mean time on IMV, ICU stay and hospital stay in the case and control groups were 8.3 vs. 13.7, 28.9 vs. 24.0 and 36.9 vs. 37.0 days, respectively, and the 90-day mortality rates were 28.0 vs. 28.0 %.

Conclusions

The use of veno-venous ECCO₂R to avoid invasive mechanical ventilation was successful in just over half of the cases. However, relevant ECCO₂R-associated complications occurred in over one-third of cases. Despite the shorter period of IMV in the ECCO₂R group there were no significant differences in length of stay or in 28- and 90-day mortality rates between the two groups. Larger, randomised studies are warranted for further assessment of the effectiveness of ECCO₂R.

     

Mortality after emergency department intubation

Introduction

The purpose of this study is to identify the rate of emergency department (ED) intubation and the mortality associated with ED intubation.

Methods

We conducted a retrospective chart review of all patients intubated in the ED between 1 January 2004 and 31 December 2004 at an urban level one trauma centre with approximately 50,000 ED visits annually. All ED intubations were identified and reviewed. Two investigators reviewed all charts and collected the following data: age, sex, and final disposition from hospital as well as reason for intubation. The main outcome measure was survival to hospital discharge.

Results

One hundred sixty-three intubations were reviewed. Of the total 163 patients, 44 (27.0%) died prior to discharge from the hospital, 42 (25.8.%) patients were discharged to a skilled nursing facility (e.g. nursing home, rehabilitation and extended care facility) and 71 (43.6%) patients were discharged home. Dividing our cohort into trauma and non-trauma subgroups, 38/126 (30.2%) of the non-trauma patients and 6/37 (16.2.%) of the trauma patients died. The mean age for all patients in our study group was 61.5 years, with trauma patients being younger than the non-trauma subgroup. The mean age for trauma patients was 50.1 while non-trauma patients had a mean age of 64.8.

Conclusions

The mortality after an ED intubation in our study population was relatively high. Further studies need to confirm these findings and help identify predictors of mortality.     

Changing use of noninvasive ventilation in critically ill patients: trends over 15 years in francophone countries

Purpose

Over the last two decades, noninvasive ventilation (NIV) has been proposed in various causes of acute respiratory failure (ARF) but some indications are debated. Current trends in NIV use are unknown.

Methods

Comparison of three multicenter prospective audits including all patients receiving mechanical ventilation and conducted in 1997, 2002, and 2011 in francophone countries.

Results

Among the 4132 patients enrolled, 2094 (51 %) required ventilatory support for ARF and 2038 (49 %) for non-respiratory conditions. Overall NIV use was markedly increased in 2010/11 compared to 1997 and 2002 (37 % of mechanically ventilated patients vs. 16 % and 28 %, P < 0.05). In 2010/11, the use of first-line NIV for ARF had reached a plateau (24 % vs. 16 % and 23 %, P < 0.05) whereas pre-ICU and post-extubation NIV had substantially increased (11 % vs. 4 % and 11 % vs. 7 %, respectively, P < 0.05). First-line NIV remained stable in acute-on-chronic RF, continued to increase in cardiogenic pulmonary edema, but decreased in de novo ARF (16 % in 2010/11 vs. 23 % in 2002, P < 0.05). The NIV success rate increased from 56 % in 2002 to 70 % in 2010/11 and remained the lowest in de novo ARF. NIV failure in de novo ARF was associated with increased mortality in 2002 but not in 2010/11. Mortality decreased over time, and overall, NIV use was associated with a lower mortality.

Conclusion

Increases in NIV use and success rate, an overall decrease in mortality, and a decrease of the adverse impact NIV failure has in de novo ARF suggest better patient selection and greater proficiency of staff in administering NIV.

Trial registration

Clinicaltrials.gov Identifier NCT01449331.

     

Acute hypoxemic respiratory failure in immunocompromised patients: the Efraim multinational prospective cohort study

Background

In immunocompromised patients with acute hypoxemic respiratory failure (ARF), initial management aims primarily to avoid invasive mechanical ventilation (IMV).

Methods

To assess the impact of initial management on IMV and mortality rates, we performed a multinational observational prospective cohort study in 16 countries (68 centers).

Results

A total of 1611 patients were enrolled (hematological malignancies 51.9%, solid tumors 35.2%, systemic diseases 17.3%, and solid organ transplantation 8.8%). The main ARF etiologies were bacterial (29.5%), viral (15.4%), and fungal infections (14.7%), or undetermined (13.2%). On admission, 915 (56.8%) patients were not intubated. They received standard oxygen (N = 496, 53.9%), high-flow oxygen (HFNC, N = 187, 20.3%), noninvasive ventilation (NIV, N = 153, 17.2%), and NIV + HFNC (N = 79, 8.6%). Factors associated with IMV included age (hazard ratio = 0.92/year, 95% CI 0.86–0.99), day-1 SOFA (1.09/point, 1.06–1.13), day-1 PaO₂/FiO₂ (1.47, 1.05–2.07), ARF etiology (Pneumocystis jirovecii pneumonia (2.11, 1.42–3.14), invasive pulmonary aspergillosis (1.85, 1.21–2.85), and undetermined cause (1.46, 1.09–1.98). After propensity score matching, HFNC, but not NIV, had an effect on IMV rate (HR = 0.77, 95% CI 0.59–1.00, p = 0.05). ICU, hospital, and day-90 mortality rates were 32.4, 44.1, and 56.4%, respectively. Factors independently associated with hospital mortality included age (odds ratio = 1.18/year, 1.09–1.27), direct admission to the ICU (0.69, 0.54–0.87), day-1 SOFA excluding respiratory score (1.12/point, 1.08–1.16), PaO₂/FiO₂ < 100 (1.60, 1.03–2.48), and undetermined ARF etiology (1.43, 1.04–1.97). Initial oxygenation strategy did not affect mortality; however, IMV was associated with mortality, the odds ratio depending on IMV conditions: NIV + HFNC failure (2.31, 1.09–4.91), first-line IMV (2.55, 1.94–3.29), NIV failure (3.65, 2.05–6.53), standard oxygen failure (4.16, 2.91–5.93), and HFNC failure (5.54, 3.27–9.38).

Conclusion

HFNC has an effect on intubation but not on mortality rates. Failure to identify ARF etiology is associated with higher rates of both intubation and mortality. This suggests that in addition to selecting the appropriate oxygenation device, clinicians should strive to identify the etiology of ARF.

     

Noninvasive ventilation after early extubation in patients recovering from hypoxemic acute respiratory failure: a single-centre feasibility study

Purpose

The use of noninvasive ventilation (NIV) to facilitate discontinuation of mechanical ventilation in patients with acute hypoxemic respiratory failure (hypoxemic ARF) has never been explored. This pilot study aims to assess the feasibility of early extubation followed by immediate NIV, compared conventional weaning, in patients with resolving hypoxemic ARF.

Methods

Twenty consecutive hypoxemic patients were randomly assigned to receive either conventional weaning or NIV. The changes in arterial blood gases and respiratory rate were compared between the two groups at 1, 12, 24 and 48?h. Differences in the rate of extubation failure, ICU and hospital mortality, number of invasive-ventilation-free-days at day 28, septic complications, number of tracheotomies, days and rates of continuous intravenous sedation, and ICU length of stay were also determined.

Results

No patient interrupted the study protocol. Arterial blood gases were similar during invasive mechanical ventilation, 1?h after NIV application following extubation, and after 12, 24 and 48?h. Respiratory rate was higher after 1?h in the NIV group, but no different after 12, 24 and 48?h. The number of invasive-ventilation-free-days at day 28 was 20?±?8 (min?=?0, max?=?25) days in the treatment group and 10?±?9 (min?=?0, max?=?25) days in the control group (p?=?0.014). The rate of extubation failure, ICU and hospital mortality, tracheotomies, septic complications, days and rates of continuous sedation, and ICU length of stay were not significantly different between the two groups.

Conclusions

In a highly experienced centre NIV may be used to facilitate discontinuation of mechanical ventilation in selected patients with resolving hypoxemic ARF.     

Acute respiratory distress syndrome in patients with malignancies

Purpose

Little attention has been given to ARDS in cancer patients, despite their high risk for pulmonary complications. We sought to describe outcomes in cancer patients with ARDS meeting the Berlin definition.

Methods

Data from a cohort of patients admitted to 14 ICUs between 1990 and 2011 were used for a multivariable analysis of risk factors for hospital mortality.

Results

Of 1,004 included patients (86 % with hematological malignancies and 14 % with solid tumors), 444 (44.2 %) had neutropenia. Admission SOFA score was 12 (10–13). Etiological categories were primary infection-related ARDS (n = 662, 65.9 %; 385 bacterial infections, 213 invasive aspergillosis, 64 Pneumocystis pneumonia); extrapulmonary septic shock-related ARDS (n = 225, 22.4 %; 33 % candidemia); noninfectious ARDS (n = 76, 7.6 %); and undetermined cause (n = 41, 4.1 %). Of 387 (38.6 %) patients given noninvasive ventilation (NIV), 276 (71 %) subsequently required endotracheal ventilation. Hospital mortality was 64 % overall. According to the Berlin definition, 252 (25.1 %) patients had mild, 426 (42.4 %) moderate and 326 (32.5 %) severe ARDS; mortality was 59, 63 and 68.5 %, respectively (p = 0.06). Mortality dropped from 89 % in 1990–1995 to 52 % in 2006–2011 (p < 0.0001). Solid tumors, primary ARDS, and later admission period were associated with lower mortality. Risk factors for higher mortality were allogeneic bone-marrow transplantation, modified SOFA, NIV failure, severe ARDS, and invasive fungal infection.

Conclusions

In cancer patients, 90 % of ARDS cases are infection-related, including one-third due to invasive fungal infections. Mortality has decreased over time. NIV failure is associated with increased mortality. The high mortality associated with invasive fungal infections warrants specific studies of early treatment strategies.     

Non-invasive ventilation for acute hypoxemic respiratory failure: intubation rate and risk factors

Introduction

We assessed rates and predictive factors of non-invasive ventilation (NIV) failure in patients admitted to the intensive care unit (ICU) for non-hypercapnic acute hypoxemic respiratory failure (AHRF).

Methods

This is an observational cohort study using data prospectively collected over a three-year period in a medical ICU of a university hospital.

Results

Among 113 patients receiving NIV for AHRF, 82 had acute respiratory distress syndrome (ARDS) and 31 had non-ARDS. Intubation rates significantly differed between ARDS and non-ARDS patients (61% versus 35%, P = 0.015) and according to clinical severity of ARDS: 31% in mild, 62% in moderate, and 84% in severe ARDS (P = 0.0016). In-ICU mortality rates were 13% in non-ARDS, and, respectively, 19%, 32% and 32% in mild, moderate and severe ARDS (P = 0.22). Among patients with moderate ARDS, NIV failure was lower among those having a PaO₂/FiO₂ >150 mmHg (45% vs. 74%, p = 0.04). NIV failure was associated with active cancer, shock, moderate/severe ARDS, lower Glasgow coma score and lower positive end-expiratory pressure level at NIV initiation. Among intubated patients, ICU mortality rate was 46% overall and did not differ according to the time to intubation.

Conclusions

With intubation rates below 35% in non-ARDS and mild ARDS, NIV stands as the first-line approach; NIV may be attempted in ARDS patients with a PaO₂/FiO₂ > 150. By contrast, 84% of severe ARDS required intubation and NIV did not appear beneficial in this subset of patients. However, the time to intubation had no influence on mortality.