Non-invAsive VentIlation for early General wArd respiraTory failurE (NAVIGATE): A multicenter randomized controlled study. Protocol and statistical analysis plan.

OBJECTIVE: Few randomized trials have evaluated the use of non-invasive ventilation (NIV) for early acute respiratory failure (ARF) in non-intensive care unit (ICU) wards. The aim of this study is to test the hypothesis that early NIV for mild-moderate ARF in non-ICU wards can prevent development of severe ARF. DESIGN: Pragmatic, parallel group, randomized, controlled, multicenter trial. SETTING: Non-intensive care wards of tertiary centers. PATIENTS: Non-ICU ward patients with mild to moderate ARF without an established indication for NIV. INTERVENTIONS: Patients will be randomized to receive or not receive NIV in addition to best available care. MEASUREMENTS AND MAIN RESULTS: We will enroll 520 patients, 260 in each group. The primary endpoint of the study will be the development of severe ARF. Secondary endpoints will be 28-day mortality, length of hospital stay, safety of NIV in non-ICU environments, and a composite endpoint of all in-hospital respiratory complications. CONCLUSIONS: This trial will help determine whether the early use of NIV in non-ICU wards can prevent progression from mild-moderate ARF to severe ARF.

Noninvasive Ventilation After Thoracoabdominal Aortic Surgery: A Pilot Randomized Controlled Trial.

OBJECTIVE: To assess the beneficial effects of noninvasive ventilation in treating postoperative pulmonary complications in patients undergoing thoracoabdominal aortic aneurysm (TAAA) open repair surgery. DESIGN: Randomized controlled trial. SETTING: University tertiary-care hospital. PARTICIPANTS: Forty patients who underwent elective TAAA open repair. INTERVENTIONS: Patients were randomized to the "noninvasive ventilation" group, receiving 2-hour cycles of noninvasive ventilation every 8 hours for at least 3 days in addition to the best available postoperative treatment currently in use at the authors' institution versus the "standard" group, not receiving noninvasive ventilation treatment MEASUREMENTS AND MAIN RESULTS: The primary outcome of clinical worsening, described as a composite outcome of need for therapeutic noninvasive ventilation, need for mechanical ventilation owing to respiratory causes, need for intensive care unit admission owing to respiratory causes, and in-hospital mortality, occurred in 2 (11%) patients in the noninvasive ventilation group versus 12 (57%) in the standard group (p = 0.002; relative risk 0.18; 95% confidence interval 0.047-0.72). CONCLUSION: Noninvasive ventilation is a promising, affordable, and easy-to-use tool to prevent postoperative respiratory complications after TAAA open surgical repair.

Continuous Positive Airway Pressure Versus Oxygen Therapy in the Cardiac Surgical Ward: A Randomized Trial.

BACKGROUND: Noninvasive ventilation (NIV) is a common technique to manage patients with acute respiratory failure in the intensive care unit. However, use of NIV in general wards is less well described. The authors' aim was to demonstrate efficacy of NIV, applied in a cardiac surgery ward, in improving oxygenation in patients who developed hypoxemic acute respiratory failure after being discharged from the intensive care unit. DESIGN: Randomized, open-label trial. SETTING: University hospital. PARTICIPANTS: Sixty-four patients with hypoxemia (PaO2/FIO2 ratio between 100 and 250) admitted to the main ward after cardiac surgery. INTERVENTIONS: Patients were randomized to receive standard treatment (oxygen, early mobilization, a program of breathing exercises and diuretics) or continuous positive airway pressure in addition to standard treatment. Continuous positive airway pressure was administered 3 times a day for 2 consecutive days. Every cycle lasted 1 to 3 hours. All patients completed their 1-year follow-up. Data were analyzed according to the intention-to-treat principle. MEASUREMENTS AND MAIN RESULTS: The primary endpoint was the number of patients with PaO2/FIO2<200 48 hours after randomization. Continuous positive airway pressure use was associated with a statistically significant reduction in the number of patients with PaO2/FIO2<200 (4/33 [12%] v 14/31 [45%], p = 0.003). One patient in the control group died at the 30-day follow-up. CONCLUSIONS: Among patients with acute respiratory failure following cardiac surgery, administration of continuous positive airway pressure in the main ward was associated with improved respiratory outcome. This was the first study that was performed in the main ward of post-surgical patients with acute respiratory failure.

Effects of non-invasive ventilation on reintubation rate: a systematic review and meta-analysis of randomised studies of patients undergoing cardiothoracic surgery.

OBJECTIVE: To estimate the effect of non-invasive mechanical ventilation (NIV) on the rate of reintubation among patients undergoing cardiothoracic surgery. DESIGN: A meta-analysis of randomised trials. DATA SOURCES: Medline, Embase, and the Cochrane Central Register of clinical trials were searched (April 2012) for pertinent studies by two trained investigators. International experts were contacted. DATA EXTRACTION: Articles were assessed by two trained investigators, with divergences resolved by consensus. Inclusion criterion was random allocation to NIV versus standard treatment without restrictions on duration or modalities of the treatment delivered. DATA SYNTHESIS: Fourteen studies enrolling 1211 patients were included in the meta-analysis. NIV reduced the reintubation rate (risk ratio [RR], 0.29; 95% CI, 0.16-0.53; P for efficacy < 0.0001; I2 = 0), hospital length of stay and mortality. Subgroup analyses suggested that the benefits of NIV are more important in patients with ongoing acute respiratory failure (RR, 0.25; 95% CI, 0.07-0.89) and in those at high risk of developing postoperative pulmonary complications (RR, 0.19; 95% CI, 0.04-0.84). Analyses including prophylactic studies in patients at low risk did not show a significant effect of NIV on reintubation rate (RR = 0.42; 95% CI, 0.12-1.48) and on any of the outcomes considered except for oxygenation. CONCLUSIONS: NIV seems to be effective in reducing reintubation rate after cardiothoracic surgery. The results of this meta-analysis should be confirmed by large randomised controlled studies.

Validation of the treadmill Six-Minute Walk Test in people following cardiac surgery.

BACKGROUND: The Six-Minute Walk Test (6MWT) often is used to measure exercise capacity in people with cardiopulmonary diseases but has some disadvantages. The 6MWT administered on a treadmill (Tr6MWT) requires less physical space and allows for easier monitoring of vital parameters than the traditional 6MWT. OBJECTIVE: The objectives of this study were: (1) to analyze the validity of the Tr6MWT in people who underwent cardiac surgery; (2) to compare the reliability, responsiveness, and people's tolerance of the Tr6MWT with those of the 6MWT; and (3) to evaluate the agreement between the 2 tests. DESIGN: This study was designed to assess reliability and validity. METHODS: Twenty-six participants who were inpatients were assessed before a 2-week rehabilitation program. Twenty of them also were assessed after rehabilitation. All participants performed 3 Tr6MWT trials and 3 6MWT trials that were randomly assigned on 2 consecutive days. RESULTS: The Pearson r correlation coefficient between the Tr6MWT and the 6MWT was .72, indicating satisfactory concurrent validity. The Tr6MWT was as well tolerated as the 6MWT. The Tr6MWT produced reproducible results after 2 practice tests, whereas the 6MWT did so after only 1 practice test. Both tests showed high test-retest reliability (intraclass correlation coefficient of >.94; standard errors of measurement of 23 m for the Tr6MWT and 18.5 m for the 6MWT). The Tr6MWT showed better responsiveness than the 6MWT (effect sizes of 0.9 for the Tr6MWT and 0.6 for the 6MWT). The distance covered during the Tr6MWT was significantly shorter (X=62 m, SD=91) before rehabilitation but not after rehabilitation. LIMITATIONS: A crossover randomized procedure could have improved the reliability of the Tr6MWT in people who performed the 6MWT first. CONCLUSIONS: The Tr6MWT appears to be an instrument with adequate concurrent validity and to be tolerable, reliable, and responsive for the evaluation of exercise capacity in people after cardiac surgery even though it is not interchangeable with the 6MWT.