Risk factors of in-hospital mortality and discriminating capacity of NIVO score in exacerbations of COPD requiring noninvasive ventilation.

BACKGROUND: Noninvasive mechanical ventilation (NIV) is recommended as the initial mode of ventilation to treat acute respiratory failure in patients with AECOPD. The Noninvasive Ventilation Outcomes (NIVO) score has been proposed to evaluate the prognosis in patients with AECOPD requiring assisted NIV. However, it is not validated in Chinese patients. METHODS: We used data from the MAGNET AECOPD Registry study, which is a prospective, noninterventional, multicenter, real-world study conducted between September 2017 and July 2021 in China. Data for the potential risk factors of mortality were collected and the NIVO score was calculated, and the in-hospital mortality was evaluated using the NIVO risk score. RESULTS: A total of 1164 patients were included in the study, and 57 patients (4.9%) died during their hospital stay. Multiple logistic regression analysis revealed that age ≥75 years, DBP <60 mmHg, Glasgow Coma Scale ≤14, anemia and BUN >7 mmol/L were independent predictors of in-hospital mortality. The in-hospital mortality was associated with an increase in the risk level of NIVO score and the difference was statistically significant (p < .001). The NIVO risk score showed an acceptable accuracy for predicting the in-hospital mortality in AECOPD requiring assisted NIV (AUC: 0.657, 95% CI: 0.584-0.729, p < .001). CONCLUSION: Our findings identified predictors of mortality in patients with AECOPD receiving NIV, providing useful information to identify severe patients and guide the management of AECOPD. The NIVO score showed an acceptable predictive value for AECOPD receiving NIV in Chinese patients, and additional studies are needed to develop and validate predictive scores based on specific populations.

Analgo-sedation in Patients on Non-invasive Mechanical Ventilation: Need for Guideline Recommendation.

Shrinath V, Marwah V, Jyothis MC. Analgo-sedation in Patients on Non-invasive Mechanical Ventilation: Need for Guideline Recommendation. Indian J Crit Care Med 2024;28(3):309-310.

NONINVASIVE MECHANICAL VENTILATION IN COVID-19 RELATED ACUTE RESPIRATORY FAILURE.

Coronavirus disease 2019 (COVID-19) is presented with a wide range of symptoms, from asymptomatic disease to severe and progressive interstitial pneumonia. As part of interstitial pneumonia, respiratory failure is typically presented as hypoxia and is the most common cause of hospitalization. When oxygen therapy fails, continuous positive airway pressure (CPAP) or noninvasive mechanical ventilation (NIV) are used as respiratory support measures of first choice. Noninvasive respiratory support (NIRS) is applied in order to save intensive care unit resources and to avoid complications related to invasive mechanical ventilation. Emerging evidence has shown that the use of CPAP or NIV in the management of acute hypoxemic respiratory failure in COVID-19 reduces the need for intubation and mortality. The advantage of NIRS is the feasibility of its application on wards. NIV could be administered via a face mask or helmet interface. Helmet adheres better than mask and therefore leakage is reduced, a delivery of positive end-expiratory pressure is more accurate, and the risk of nosocomial transmission of infections is lowered. Patients on NIRS must be carefully monitored so that further respiratory deterioration is not overlooked and additional measures of care including timely intubation and invasive mechanical ventilation could be performed if needed.

Remifentanil versus Dexmedetomidine in Cardiac Surgery Patients with Noninvasive Ventilation Intolerance: Protocol for the REDNIVI Trial.

BACKGROUND: Respiratory failure is one of the most common complications following cardiac surgery. Although noninvasive ventilation (NIV) has been an effective treatment, it has a high rate of intolerance. Both remifentanil and dexmedetomidine are used as sedatives in cardiac surgery (CS) patients with NIV intolerance. However, no randomized controlled trials have compared the effects of these drugs in relieving the intolerance. METHODS: REDNIVI will be a multicenter, prospective, single-blind, randomized controlled trial carried out in six clinical sites in China. Subjects with NIV intolerance will be randomized to receive remifentanil or dexmedetomidine in a ratio of 1:1. Primary outcomes of intolerance remission rate at different timings (15 minutes, 1, 3, 6, 12, 24, 36, 48, 60, 72 hours after initiation of treatment) and 72 h average remission rate will be determined. In addition, secondary outcomes such as mortality, duration of intensive care unit (ICU) stay, duration of mechanical ventilation (MV), the need for endotracheal intubation, hemodynamic changes, and delirium incidence will also be determined. CONCLUSIONS: This trial will provide evidence to determine the effects of remifentanil and dexmedetomidine in patients with NIV intolerance after cardiac surgery. CLINICAL TRIAL REGISTRATION: This study has been registered on ClinicalTrials.gov (NCT04734418).

Nutritional risk screening in noninvasively mechanically ventilated critically ill adult patients: A feasibility trial.

BACKGROUND: Malnutrition rates for critically ill patients being admitted to the intensive care unit (ICU) are reported to range from 38% to 78%. Malnutrition in the ICU is associated with increased mortality, morbidity, length of hospital admission, and ICU readmission rates. The high volume of ICU admissions means that efficient screening processes to identify patients at nutritional or malnutrition risk are imperative to appropriately prioritise nutrition intervention. As the proportion of noninvasively mechanically ventilated patients in the ICU increases, the feasibility of using nutrition risk screening tools in this population needs to be established. OBJECTIVES: The aim of this study was to compare the feasibility of using the Malnutrition Universal Screening Tool (MUST) with the modified NUtriTion Risk In the Critically ill (mNUTRIC) score for identifying patients at nutritional or malnutrition risk in this population. METHODS: A single-centre, prospective, descriptive, feasibility study was conducted. The MUST and mNUTRIC tool were completed within 24 h of ICU admission in a convenience sample of noninvasively mechanically ventilated adult patients (≥18 years) by a trained allied health assistant. The number (n) of eligible patients screened, time to complete screening (minutes), and barriers to completion were documented. Data are presented as mean (standard deviation), and the independent samples t-test was used for comparisons between tools. RESULTS: Twenty patients were included (60% men; aged 65.3 [13.9] years). Screening using the MUST took a significantly shorter time to complete than screening using the mNUTRIC tool (8.1 [2.8] vs 22.1 [5.6] minutes; p = 0.001). Barriers to completion included obtaining accurate weight history for the MUST and time taken for collection of information and overall training requirements to perform mNUTRIC. CONCLUSIONS: The MUST took less time and had fewer barriers to completion than mNUTRIC. The MUST may be the more feasible nutrition risk screening tool for use in noninvasively mechanically ventilated critically ill adults.

Implications of early respiratory support strategies on disease progression in critical COVID-19: a matched subanalysis of the prospective RISC-19-ICU cohort.

BACKGROUND: Uncertainty about the optimal respiratory support strategies in critically ill COVID-19 patients is widespread. While the risks and benefits of noninvasive techniques versus early invasive mechanical ventilation (IMV) are intensely debated, actual evidence is lacking. We sought to assess the risks and benefits of different respiratory support strategies, employed in intensive care units during the first months of the COVID-19 pandemic on intubation and intensive care unit (ICU) mortality rates. METHODS: Subanalysis of a prospective, multinational registry of critically ill COVID-19 patients. Patients were subclassified into standard oxygen therapy ≥10 L/min (SOT), high-flow oxygen therapy (HFNC), noninvasive positive-pressure ventilation (NIV), and early IMV, according to the respiratory support strategy employed at the day of admission to ICU. Propensity score matching was performed to ensure comparability between groups. RESULTS: Initially, 1421 patients were assessed for possible study inclusion. Of these, 351 patients (85 SOT, 87 HFNC, 87 NIV, and 92 IMV) remained eligible for full analysis after propensity score matching. 55% of patients initially receiving noninvasive respiratory support required IMV. The intubation rate was lower in patients initially ventilated with HFNC and NIV compared to those who received SOT (SOT: 64%, HFNC: 52%, NIV: 49%, p = 0.025). Compared to the other respiratory support strategies, NIV was associated with a higher overall ICU mortality (SOT: 18%, HFNC: 20%, NIV: 37%, IMV: 25%, p = 0.016). CONCLUSION: In this cohort of critically ill patients with COVID-19, a trial of HFNC appeared to be the most balanced initial respiratory support strategy, given the reduced intubation rate and comparable ICU mortality rate. Nonetheless, considering the uncertainty and stress associated with the COVID-19 pandemic, SOT and early IMV represented safe initial respiratory support strategies. The presented findings, in agreement with classic ARDS literature, suggest that NIV should be avoided whenever possible due to the elevated ICU mortality risk.

Early Inspiratory Effort Assessment by Esophageal Manometry Predicts Noninvasive Ventilation Outcome in De Novo Respiratory Failure. A Pilot Study.

Rationale: The role of inspiratory effort still has to be determined as a potential predictor of noninvasive mechanical ventilation (NIV) failure in acute hypoxic de novo respiratory failure.Objectives: To explore the hypothesis that inspiratory effort might be a major determinant of NIV failure in these patients.Methods: Thirty consecutive patients with acute hypoxic de novo respiratory failure admitted to a single center and candidates for a 24-hour NIV trial were enrolled. Clinical features, tidal change in esophageal pressure (ΔPes), tidal change in dynamic transpulmonary pressure (ΔPl), expiratory Vt, and respiratory rate were recorded on admission and 2-4 to 12-24 hours after NIV start and were tested for correlation with outcomes.Measurements and Main Results: ΔPes and ΔPes/ΔPl ratio were significantly lower 2 hours after NIV start in patients who successfully completed the NIV trial (n = 18) compared with those who needed endotracheal intubation (n = 12) (median [interquartile range], 11 [8-15] cm H2O vs. 31.5 [30-36] cm H2O; P < 0.0001), whereas other variables differed later. ΔPes was not related to other predictors of NIV failure at baseline. NIV-induced reduction in ΔPes of 10 cm H2O or more after 2 hours of treatment was strongly associated with avoidance of intubation and represented the most accurate predictor of treatment success (odds ratio, 15; 95% confidence interval, 2.8-110; P = 0.001 and area under the curve, 0.97; 95% confidence interval, 0.91-1; P < 0.0001).Conclusions: The magnitude of inspiratory effort relief as assessed by ΔPes variation within the first 2 hours of NIV was an early and accurate predictor of NIV outcome at 24 hours.Clinical trial registered with www.clinicaltrials.gov (NCT03826797).

Diaphragm dysfunction detected with ultrasound to predict noninvasive mechanical ventilation failure: A prospective cohort study.

OBJECTIVE: This study aimed to examine the use of point-of-care ultrasonography (POCUS) in detecting diaphragmatic dysfunction (DD) and evaluate its ability to predict noninvasive mechanical ventilation (NIV) failure in patients presented to the emergency department with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). METHODS: In this prospective cohort study, the diaphragm was examined using POCUS in patients with AECOPD. DD was defined as a diaphragm thickening fraction of less than 20% during spontaneous breathing. NIV failure was the primary outcome of the study, and duration of hospital stay and in-hospital mortality were the secondary outcomes. Specificity, sensitivity, positive predictive value, and negative predictive value were estimated for predicting NIV failure in DD and evaluating the diagnostic performance of POCUS. RESULTS: 60 patients were enrolled the study. NIV failure was found in 11 (73.3%) of 15 patients with DD and in 2 (4.4%) of 45 patients without DD. In predicting NIV failure, DD had a sensitivity of 84.6% (95% confidence interval [CI]:54.6-98.1), specificity of 91.5% (95% CI:79.6-97.6), positive predictive value of 73.3% (95% CI:51.2-87.8), and negative predictive value of 95.6% (95% CI:85.7-98.7). The duration of hospital stay was not different between groups (p = .065). No in-hospital mortality was seen in patients without DD. CONCLUSIONS: DD has high sensitivity and specificity in predicting NIV failure in patients admitted to the emergency department with AECOPD. DD can be assessed by an experienced clinician noninvasively using POCUS in emergency departments.

Helmet NIV in Acute Hypoxemic Respiratory Failure due to COVID-19: Change in PaO2/FiO2 Ratio a Predictor of Success.

In acute respiratory failure due to severe coronavirus disease 2019 (COVID-19) pneumonia, mechanical ventilation remains challenging and may result in high mortality. The use of noninvasive ventilation (NIV) may delay required invasive ventilation, increase adverse outcomes, and have a potential aerosol risk to caregivers. Data of 30 patients were collected from patient files and analyzed. Twenty-one (70%) patients were weaned successfully after helmet-NIV support (NIV success group), and invasive mechanical ventilation was required in 9 (30%) patients (NIV failure group) of which 8 (26.7%) patients died. In NIV success vs failure patients, the mean baseline PaO2/FiO2 ratio (PFR) (147.2 ± 57.9 vs 156.8 ± 59.0 mm Hg; p = 0.683) and PFR before initiation of helmet (132.3 ± 46.9 vs 121.6 ± 32.7 mm Hg; p = 0.541) were comparable. The NIV success group demonstrated a progressive improvement in PFR in comparison with the failure group at 2 hours (158.8 ± 56.1 vs 118.7 ± 40.7 mm Hg; p = 0.063) and 24 hours (PFR-24) (204.4 ± 94.3 vs 121.3 ± 32.6; p = 0.016). As predictor variables, PFR-24 and change (delta) in PFR at 24 hours from baseline or helmet initiation (dPFR-24) were significantly associated with NIV success in univariate analysis but similar significance could not be reflected in multivariate analysis perhaps due to a small sample size of the study. The PFR-24 cutoff of 161 mm Hg and dPFR-24 cutoff of -1.44 mm Hg discriminate NIV success and failure groups with the area under curve (confidence interval) of 0.78 (0.62-0.95); p = 0.015 and 0.74 (0.55-0.93); p = 0.039, respectively. Helmet interface NIV may be a safe and effective tool for the management of patients with severe COVID-19 pneumonia with acute respiratory failure. More studies are needed to further evaluate the role of helmet NIV especially in patients with initial PFR <150 mm Hg to define PFR/dPFR cutoff at the earliest time point for prediction of helmet-NIV success. How to cite this article Jha OK, Kumar S, Mehra S, Sircar M, Gupta R. Helmet NIV in Acute Hypoxemic Respiratory Failure due to COVID-19: Change in PaO2/FiO2 Ratio a Predictor of Success. Indian J Crit Care Med 2021;25(10):1137-1146.

Super Obesity in the Medical Intensive Care Unit.

BACKGROUND: Studies exploring the effect of body mass index (BMI) on outcomes in the intensive care unit (ICU) have yielded mixed results, with few studies assessing patients at the extremes of obesity. We sought to understand the clinical characteristics and outcomes of patients with super obesity (BMI > 50 kg/m2) as compared to morbid obesity (BMI > 40 kg/m2) and obesity (BMI > 30 kg/m2). METHODS: A retrospective review of patients admitted to the Los Angeles County + University of Southern California medical intensive care unit (MICU) service between 2008 and 2013 was performed. The first 150 patients with BMI 30 to 40, 40 to 50, and 50+ were separated into groups. Demographic data, comorbid conditions, reason for admission, Acute Physiology and Chronic Health Evaluation II (APACHE II) scores, serum bicarbonate, and arterial carbon dioxide pressure (Pco 2) at admission were collected. Hospital and ICU length of stay (LOS), discharge disposition, mortality, use of mechanical ventilation (invasive and noninvasive), use of radiography, and other clinical outcomes were also recorded. RESULTS: There was no difference in age, sex, and APACHE II score among the 3 groups. A pulmonary etiology was the most common reason for admission in the higher BMI categories (P < .001). There was no difference in mortality among the groups. Intensive care unit and hospital LOS rose with increasing BMI (P < .001). Patients admitted for pulmonary etiologies and higher BMIs had an increased ICU and hospital LOS (P < .001). Super obese patients used significantly more noninvasive mechanical ventilation (NIMV, P < .001). There were no differences in the use of invasive mechanical ventilation across the groups. CONCLUSION: Super obese patients are most commonly admitted to the MICU with pulmonary diagnoses and have an increased use of noninvasive ventilation. Super obesity was not associated with increased ICU mortality. Clinicians should be prepared to offer NIMV to super obese patients and anticipate a longer LOS in this group.

Nutrition-related outcomes and dietary intake in non-mechanically ventilated critically ill adult patients: A pilot observational descriptive study.

BACKGROUND: Critically ill patients who do not receive invasive mechanical ventilation (IMV) are a growing population, experiencing complex interventions that may impair dietary intake and nutrition-related outcomes. OBJECTIVES: The objectives of this study were to quantify intake and nutrition-related outcomes of non-IMV critically ill patients and to establish feasibility of methods to measure nutrition-related outcomes in this population. METHODS: Non-IMV adult patients expected to remain in the intensive care unit (ICU) for ≥24 h were eligible. Nutrition-related outcomes were assessed at baseline by subjective global assessment (SGA); on alternate study days by mid-upper arm circumference (MUAC), calf circumference (CC), and ultrasound of quadriceps muscle layer thickness (QMLT); and daily by body weight and bioelectrical impedance analysis (BIA). Data were censored at day 5 or ICU discharge. Dietary intake from all sources, including oral intake via investigator-led weighed food records, was quantified on days 1-3. Feasibility was defined as data completion rate ≥70%. Data are expressed as mean (standard deviation) or median [interquartile range (IQR)]. RESULTS: Twenty-three patients consented (50% male; 53 [42-64] y; ICU stay: 2.8 [1.9-4.0] d). Nutrition-related outcomes at baseline and ICU discharge were as follows: MUAC: 33.2 (8.6) cm (n = 18) and 29.3 (5.4) cm (n = 6); CC: 39.5 (7.4) cm (n = 16) and 37.5 (6.2) cm (n = 6); body weight: 95.3 (34.8) kg (n = 19) and 95.6 (41.0) kg (n = 10); and QMLT: 2.6 (0.8) cm (n = 15) and 2.5 (0.3) cm (n = 5), respectively. Oral intake provided 3155 [1942-5580] kJ and 32 [20-53] g protein, with poor appetite identified as a major barrier. MUAC, CC, QMLT, and SGA were feasible, while BIA and body weight were not. CONCLUSIONS: Oral intake in critically ill patients not requiring IMV is below estimated requirements, largely because of poor appetite. The small sample and short study duration were not sufficient to quantify changes in nutrition-related outcomes. MUAC, CC, QMLT, and SGA are feasible methods to assess nutrition-related outcomes at a single time point in this population.

Role of Noninvasive Oxygen Therapy Strategies in COVID-19 Patients: Where are We Going?

How to cite this article: Dixit SB. Role of Noninvasive Oxygen Therapy Strategies in COVID-19 Patients: Where are We Going? Indian J Crit Care Med 2020;24(10):897-898.

Noninvasive Oxygen Strategies to Manage Confirmed COVID-19 Patients in Indian Intensive Care Units: A Survey.

BACKGROUND: About 5% of hospitalized coronavirus disease 2019 (COVID-19) patients will need intensive care unit (ICU) admission for hypoxemic respiratory failure requiring oxygen support. The choice between early mechanical ventilation and noninvasive oxygen therapies, such as, high-flow nasal oxygen (HFNO) and/or noninvasive positive-pressure ventilation (NPPV) has to balance the contradictory priorities of protecting healthcare workers by minimizing aerosol-generation and optimizing resource management. This survey over two timeframes aimed to explore the controversial issue of location and noninvasive oxygen therapy in non-intubated ICU patients using a clinical vignette. MATERIALS AND METHODS: An online survey was designed, piloted, and distributed electronically to Indian intensivists/anesthetists, from private hospitals, government hospitals, and medical college hospitals (the latter two referred to as first-responder hospitals), who are directly responsible for admitting/managing patients in ICU. RESULTS: Of the 204 responses (125/481 in phase 1 and 79/320 in phase 2), 183 responses were included. Respondents from first-responder hospitals were more willing to manage non-intubated hypoxemic patients in neutral pressure rooms, while respondents from private hospitals preferred negative-pressure rooms (p < 0.001). In both the phases, private hospital doctors were less comfortable to use any form of noninvasive oxygen therapies in neutral-pressure rooms compared to first-responder hospitals (low-flow oxygen therapy: 72 vs 50%, p < 0.01; HFNO: 47 vs 24%, p < 0.01 and NPPV: 38 vs 28%, p = 0.20). INTERPRETATION: Variations existed in practices among first-responder and private intensivists/anesthetists. The resource optimal private hospital intensivists/anesthetists were less comfortable using noninvasive oxygen therapies in managing COVID-19 patients. This may reflect differential resource availability necessitating resolution at national, state, and local levels. HOW TO CITE THIS ARTICLE: Subramaniam A, Haji JY, Kumar P, Ramanathan K, Rajamani A. Noninvasive Oxygen Strategies to Manage Confirmed COVID-19 Patients in Indian Intensive Care Units: A Survey. Indian J Crit Care Med 2020;24(10):926-931.

Feasibility of Early Noninvasive Ventilation Strategy for Patients with Acute Onset Shortness of Breath in Emergency Department - A Prospective Interventional Study.

INTRODUCTION: Noninvasive ventilation (NIV) has revolutionized the initial respiratory support provided to a patient in respiratory distress presenting to emergency department. Standardization of NIV practices and safety has always been a matter of concern and debate in emergency medicine. In this study, we tried to assess the clinical outcome of NIV in respiratory failures of varied etiologies. MATERIALS AND METHODS: This study was conducted from August 2017 to August 2018 at our emergency department which is a tertiary care teaching institute. All patients presenting to the ED with shortness of breath were screened for acute respiratory failure and enrolled after confirming the inclusion criteria. RESULTS: Out of the 236 patients presenting with acute respiratory failure, 182 fulfilled the study criteria. However, 154 patients with a mean age of 55.19 + 16.73 years were enrolled in the study. Bilevel PAP was initiated in 103 patients whereas 51 patients received CPAP. 115 (74.67%) NIV trials were successful whereas 36 (23.37%) patients had to be intubated. 32 patients died among the study group among which 3 had not consented for intubation. The in-hospital mortality has been 20.77% whereas the percentage of NIV failure with consequent intubation was 25.32%. CONCLUSION: In conclusion, our study shows that NIV is not only safe and efficacious but also significantly brings down the requirement of endotracheal intubations and its complications provided proper patient selection and close monitoring is assured. HOW TO CITE THIS ARTICLE: Nizami MI, Sharma A, Jayaram K. Feasibility of Early Noninvasive Ventilation Strategy for Patients with Acute Onset Shortness of Breath in Emergency Department - A Prospective Interventional Study. Indian J Crit Care Med 2019;23(9):400-404.

Does Adherence to Domiciliary NIMV Decrease the Subsequent Hospitalizations Rates and Cost for Patients Diagnosed with COPD?

Domiciliary noninvasive mechanical ventilation (NIMV) is used for treating patients with hypercapnic chronic obstructive pulmonary disease (COPD). We aimed to evaluate the association between adherence to the treatment and subsequent hospitalizations and costs. Data from 54 (27 adherent; 27 non-adherent) patients with COPD who were undergoing NIMV treatment at home for 6 months. We assessed adherence based on digitally recorded data and checked hospital records for clinical and laboratory data, rehospitalization rates, and costs during the following 6 months. Nocturnal NIMV usage, mean daily usage of the device, and time to first hospitalization were higher in the treatment-adherent group (p < .001, p < .001, and p=.006, respectively). The percentage of active smokers, device leaks above 30 L/min, length of hospital stay, rehospitalization rates, and costs were significantly higher in the treatment-non-adherent group (p = 05, p = 006, p = 004, p = 006, and p = 01, respectively). The most frequent reasons for not using NIMV in the treatment-non-adherent group were a decreased need, dry mouth, mask incompatibility, and gastrointestinal complaints. Adherence to NIMV treatment decreases the subsequent hospitalizations rates and noncompliance leads to complications. Findings of this study may help physicians in convincing patients diagnosed with COPD of the need for correct NIMV use to prevent hospitalizations and reduce the costs of COPD treatment.

Influence of noninvasive ventilation on clinical status, dyspnea sensation and subsequent copd diagnosis.

Chronic obstructive lung disease (COPD) is a common life-threatening disease characterized by exposure to tobacco smoke, dyspnea and persistent lower airway obstruction coexistence of COPD and chronic heart failure (HF) may present a considerable challenge during both diagnostic and therapeutic processes. Herein, we report an elderly, obese male, an ex-smoker, suffering from both COPD and HF, and treated according to the applied guidelines for 15 years. On admission to hospital, the patient was diagnosed and treated for severe type 2 respiratory failure. The patient's COPD diagnosis was questioned at first, but then reconsidered after treatment described below. Noninvasive ventilation (NIV) improved the patient's clinical condition and reduced his dyspnea sensation. As a consequence, during check-ups, spirometry maneuvers could have been performed properly, revealing the underlying bronchial obstruction, which had been beforehand concealed by debilitation of respiratory muscles and decreased lung tissue compliance in a patient with chronic HF. Conclusion: NIV application in a patient with type 2 respiratory failure may significantly improve one's clinical condition, reduce dyspnea sensation and help establish an accurate diagnosis.

Initial nutritional management during noninvasive ventilation and outcomes: a retrospective cohort study.

BACKGROUND: Patients starting noninvasive ventilation (NIV) to treat acute respiratory failure are often unable to eat and therefore remain in the fasting state or receive nutritional support. Maintaining a good nutritional status has been reported to improve patient outcomes. In the present study, our primary objective was to describe the nutritional management of patients starting first-line NIV, and our secondary objectives were to assess potential associations between nutritional management and outcomes. METHODS: Observational retrospective cohort study of a prospective database fed by 20 French intensive care units. Adult medical patients receiving NIV for more than 2 consecutive days were included and divided into four groups on the basis of nutritional support received during the first 2 days of NIV: no nutrition, enteral nutrition, parenteral nutrition only, and oral nutrition only. RESULTS: Of the 16,594 patients admitted during the study period, 1075 met the inclusion criteria; of these, 622 (57.9%) received no nutrition, 28 (2.6%) received enteral nutrition, 74 (6.9%) received parenteral nutrition only, and 351 (32.7%) received oral nutrition only. After adjustment for confounders, enteral nutrition (vs. no nutrition) was associated with higher 28-day mortality (adjusted HR, 2.3; 95% CI, 1.2-4.4) and invasive mechanical ventilation needs (adjusted HR, 2.1; 95% CI, 1.1-4.2), as well as with fewer ventilator-free days by day 28 (adjusted relative risk, 0.7; 95% CI, 0.5-0.9). CONCLUSIONS: Nearly three-fifths of patients receiving NIV fasted for the first 2 days. Lack of feeding or underfeeding was not associated with mortality. The optimal route of nutrition for these patients needs to be investigated.

High-flow nasal cannula oxygen therapy is superior to conventional oxygen therapy but not to noninvasive mechanical ventilation on intubation rate: a systematic review and meta-analysis.

BACKGROUND: High-flow nasal cannula oxygen (HFNC) is a relatively new therapy used in adults with respiratory failure. Whether it is superior to conventional oxygen therapy (COT) or to noninvasive mechanical ventilation (NIV) remains unclear. The aim of the present study was to investigate whether HFNC was superior to either COT or NIV in adult acute respiratory failure patients. METHODS: A review of the literature was conducted from the electronic databases from inception up to 20 October 2016. Only randomized clinical trials comparing HFNC with COT or HFNC with NIV were included. The intubation rate was the primary outcome; secondary outcomes included the mechanical ventilation rate, the rate of escalation of respiratory support and mortality. RESULTS: Eleven studies that enrolled 3459 patients (HFNC, n = 1681) were included. There were eight studies comparing HFNC with COT, two comparing HFNC with NIV, and one comparing all three. HFNC was associated with a significant reduction in intubation rate (OR 0.52, 95% CI 0.34 to 0.79, P = 0.002), mechanical ventilation rate (OR 0.56, 95% CI 0.33 to 0.97, P = 0.04) and the rate of escalation of respiratory support (OR 0.45, 95% CI 0.31 to 0.67, P < 0.0001) when compared to COT. There was no difference in mortality between HFNC and COT utilization (OR 1.01, 95% CI 0.67 to 1.53, P = 0.96). When HFNC was compared to NIV, there was no difference in the intubation rate (OR 0.96; 95% CI 0.66 to 1.39, P = 0.84), the rate of escalation of respiratory support (OR 1.00, 95% CI 0.77 to 1.28, P = 0.97) or mortality (OR 0.85, 95% CI 0.43 to 1.68, P = 0.65). CONCLUSIONS: Compared to COT, HFNC reduced the rate of intubation, mechanical ventilation and the escalation of respiratory support. When compared to NIV, HFNC showed no better outcomes. Large-scale randomized controlled trials are necessary to prove our findings. TRIAL REGISTRATION: PROSPERO International prospective register of systematic reviews on May 25, 2016 registration no. CRD42016039581 .

The efficacy of initial ventilation strategy for adult immunocompromised patients with severe acute hypoxemic respiratory failure: study protocol for a multicentre randomized controlled trial (VENIM).

BACKGROUND: Acute respiratory failure (ARF) is still one of the most severe complications in immunocompromised patients. Our previous systematic review showed noninvasive mechanical ventilation (NIV) reduced mortality, length of hospitalization and ICU stay in AIDS/hematological malignancy patients with relatively less severe ARF, compared to invasive mechanical ventilation (IMV). However, this systematic review was based on 13 observational studies and the quality of evidence was low to moderate. The efficacy of NIV in more severe ARF and in patients with other causes of immunodeficiency is still unclear. We aim to determine the efficacy of the initial ventilation strategy in managing ARF in immunocompromised patients stratified by different disease severity and causes of immunodeficiency, and explore predictors for failure of NIV. METHODS AND ANALYSIS: The VENIM is a multicentre randomized controlled trial (RCT) comparing the effects of NIV compared with IMV in adult immunocompromised patients with severe hypoxemic ARF. Patients who meet the indications for both forms of ventilatory support will be included. Primary outcome will be 30-day all-cause mortality. Secondary outcomes will include in-hospital mortality, length of stay in hospital, improvement of oxygenation, nosocomial infections, seven-day organ failure, adverse events of intervention, et al. Subgroups with different disease severity and causes of immunodeficiency will also be analyzed. DISCUSSION: VENIM is the first randomized controlled trial aiming at assessing the efficacy of initial ventilation strategy in treating moderate and severe acute respiratory failure in immunocompromised patients. The result of this RCT may help doctors with their ventilation decisions. TRIAL REGISTRATION: ClinicalTrials.gov NCT02983851 . Registered 2 September 2016.

Ultrasound assessment of diaphragmatic function in patients with amyotrophic lateral sclerosis.

BACKGROUND AND OBJECTIVE: Evaluation of diaphragm function in Amyotrophic Lateral Sclerosis (ALS) is critical in determining when to commence non-invasive mechanical ventilation (NIV). Currently, forced vital capacity (FVC) and sniff nasal inspiratory pressure (SNIP) are volitional measures for this evaluation, but require collaboration and are poorly specific. The primary aim of this study was to assess whether diaphragmatic thickness measured by ultrasound (US) correlates with lung function impairment in ALS patients. The secondary aim was then to compare US diaphragm thickness index (ΔTdi) with a new parameter (ΔTmax index). METHODS: 41 patients with ALS and 30 healthy subjects were enrolled in the study. All subjects underwent spirometry, SNIP and diaphragm US evaluation, while arterial blood gases were measured in some patients only. US assessed diaphragm thickness (Tdi) at tidal volume (Vt) or total lung capacity (TLC), and their ratio (ΔTmax) were recorded. Changes (Δ) in Tdi indices during tidal volume (ΔTdiVt) and maximal inspiration (ΔTdiTLC) were also assessed. RESULTS: ΔTdiTLC (p <0.001) and ΔTmax (p = 0.007), but not ΔTdiVt, differed between patients and controls. Significant correlation (p < 0.05) was found between ΔTdiTLC, ΔTmax and FVC. The ROC curve analysis for comparison of individual testing showed better accuracy with Δtmax than with ΔtdiTLC for FVC (AUC 0.76 and 0.27) and SNIP (AUC 0.71 and 0.25). CONCLUSION: Diaphragm thickness assessed by ultrasound significantly correlates with global respiratory alterations in patients with ALS. ΔTmax represents a new US index of early diaphragmatic dysfunction, better related with the routinely performed lung function tests.