Noninvasive Pressure Ventilation Research Articles

Average volume-assured pressure support versus fixed pressure support in chronic hypercapnic respiratory failure: a systematic review and meta-analysis

Rationale: Chronic hypercapnic respiratory failure occurs due to alveolar hypoventilation resulting in carbon dioxide retention. This is commonly managed with noninvasive ventilation (NIV) with modalities including fixed pressure support and average volume-assured pressure support (AVAPS). However, there is limited information comparing outcomes with these two modes of ventilator support in the management of chronic hypercapnic respiratory failure. Objective: This review and meta-analysis analyze the outcomes with fixed pressure NIV versus average volume-assured pressure support NIV in managing chronic obstructive pulmonary disease (COPD) with chronic hypercapnic respiratory failure, focusing on patients’ perception of symptom burden and gas exchange based on arterial blood gases. Search methods: PubMed, Embase, Cochrane Central Register of Controlled Trials, and Web of Science databases were searched; the latest search date was December 1, 2023. Inclusion criteria: randomized control trials and crossover studies in English in adults over the age of 19 with the diagnosis of COPD and chronic hypercapnic respiratory failure. Exclusion criteria: patients less than 19 years old, patients with acute exacerbations, and patients with central respiratory failure or neuromuscular disease. Outcomes included blood gas analysis after use of NIV measured in mmHg and patient perception of mental health, symptom burden, and comfort. Results for each outcome were analyzed in RevMan using an inverse variance statistical method with a fixed effect analysis. The final analysis included 7 studies with 252 participants. Results: The patients were 64 ± 9 years old. Baseline pulmonary function testing showed a forced expiratory volume in the first second (FEV1) of 34.6 ± 14.2 % predicted, consistent with severe COPD per GOLD criteria, and a baseline PaCO2 of 55.2 ± 9.2 mmHg. Primary outcomes for ventilation showed no statistical difference between AVAPS and fixed pressure support groups in PaCO2 (Odds Ratio [OR] -1.51; 95% Confidence Interval [CI]: -3.18, 0.16; p=0.08). Patient perceived outcomes were evaluated using several questionnaires, including St. George Respiratory Questionnaire (SGRQ), Short Form 36 Health Survey Questionnaire (SF-36), and Visual Analogue Scale (VAS). Comparable results were not available for all studies, but no statistically significant differences were found when comparing study results. Conclusions: There was little or no clinically significant difference between fixed pressure support and AVAPS in gas exchange. There are inadequate data to draw conclusions about the effect of fixed pressure support compared to AVAPS on patient perceived outcomes, such as comfort and symptom burden. No studies evaluated mortality benefit, cost effectiveness, or hospitalizations. Key words: COPD, chronic hypercapnic respiratory failure, non-invasive ventilation, average volume-assured pressure support ventilation

A comparison of two weaning strategies for non-invasive ventilation in chronic obstructive pulmonary disease patients with acute respiratory failure.

Non-Invasive Ventilation (NIV) is a crucial therapy for managing acute exacerbations of Chronic Obstructive Pulmonary Disease (COPD) with hypercapnic respiratory failure. Research has shown that NIV can decrease the rate of endotracheal intubation, length of hospital and Intensive Care Unit stays, and mortality. There are three main strategies for weaning patients off NIV: gradual reduction of NIV duration, gradual reduction of NIV pressure support, and immediate cessation of NIV. To compare the rate of successful withdrawal of COPD patients with acute hypercapnic respiratory failure, one group will use a stepwise reduction of duration of NIV, while the other group will use a stepwise reduction of pressure support. This study was a prospective observational study conducted at the Department of Pulmonary Medicine, Institute of Chest Diseases, Government Medical College, Kozhikode, over a period of 15months. The study population consisted of all COPD patients admitted to the Pulmonary Medicine ward or ICU with acute hypercapnic respiratory failure who were managed with non-invasive ventilation (NIV) without the need for invasive mechanical ventilation. Exclusions included patients requiring NIV for respiratory diseases other than COPD, those with significant comorbiditieslike acute left ventricular failure or fluid overload states as in chronic kidney disease, COVID-19 positive patients, patients on home NIV, patients who needed intubation early in treatment, and patients unwilling to participate in the study. The sample size was 140. Initial NIV settings and other management decisions prior to enrolment in the study were made by the treating physician according to standard protocols. Once weaning criteria were met (i.e., arterial pH > 7.35, SpO2 ≥ 90% at an FiO2 ≤ 50%, respiratory rate ≤ 25 breaths per minute, heart rate ≤ 120 beats per minute, systolic BP > 90mm Hg, and no signs of respiratory distress), patients were assigned to either group 1 or group 2 by purposive sampling. Group 1: stepwise reduction of duration of NIV use, with a reduction to 16h per day on day 1 of enrolment, 12h on day 2 (including 6-8h of nocturnal NIV), 6-8h on day 3, and NIV withdrawal on day 4. Group 2: stepwise reduction of pressure support, with pressure support reduced by 2-4cm every 4-6h until Inspiratory Positive Airway Pressure is < 8cm H2O and Expiratory Positive Airway Pressure is < 4cm H2O, followed by NIV withdrawal. The clinical outcome was classified as either improved or weaning failure. Improved was defined as an objective or subjective sense of improvement. Weaning failure was defined as the presence of any of the following: respiratory rate ≥ 25/minute or increase of ≥ 50% from baseline, heart rate ≥ 140/minute or increase of ≥ 20% from baseline, SpO2 ≤ 90% on FiO2 ≥ 50%, arterial pH ≤ 7.35, or respiratory distress. Data was collected using a pro forma that included demographic details, smoking status, GOLD COPD category, comorbidities, and vital signs. ABG parameters, NIV settings at the time of hospital admission, at the time of study enrolment, and 48h after weaning were also recorded. Independent sample t-test was used to test the statistical significance of the difference between means of variables between the two groups. Pearson Chi square test and Fisher's exact test were used to compare categorical variables between the groups. A p-value of < 0.05 was considered statistically significant. NIV was successfully withdrawn in 56/70 (80%) and 50/70 (71.4%) patients in Groups 1 and 2, respectively. This difference was not statistically significant. The length of hospital stay was longer in the stepwise reduction of duration group (Group 1), but this was not statistically significant. On comparison of two methods of NIV withdrawal, it was found that neither method is superior to the other in terms of weaning failure, intubation rates, and average length of hospital stay.

Severe asthma, more than that?

I was recently invited to write about the development of asthma management in the past decade. Biologic therapy came to my mind, and I was fascinated by the concept that asthma remission can potentially be achieved with this treatment (https://erj.ersjournals.com/content/early/2022/03/17/13993003.02583-2021). At the same time, I reflected on the management of one of my patients with severe asthma treated with biologics and the importance of looking for and managing comorbidities when treating patients with severe asthma. She was a young lady, and it was after more than a year of treatment with various agents for severe asthma, including high-dose inhaled corticosteroids, long-acting beta-agonist, anti-muscarinic agent, montelukast, azithromycin, systemic steroid and biologics (two biologics, started with one and then changed to the other with lack of effect) that we made the diagnosis of inducible laryngeal obstruction (ILO) (https://erj.ersjournals.com/content/50/3/1602221) that was causing the recurrent ‘asthma exacerbations’ and ICU admissions. Correct diagnosis is crucial for the treatment of asthma. However, having a confirmed diagnosis of asthma does not mean that it is the sole cause of respiratory symptoms/asthma exacerbations. This lady had features typical of asthma, including positive bronchodilator reversibility and her lung function varied with time with lower FEV1 at times of poor control or attacks. She also had Type-2 high asthma with high eosinophil blood count and exhaled nitric oxide levels. At the start of the illness, the patient improved with systemic steroid during hospitalisations. We did our usual workup for assessing comorbidities, such as looking for rhinitis and gastroesophageal reflux disease and excluded eosinophilic granulomatosis with polyangiitis. However, the young lady subsequently had more ‘asthma attacks’, and those episodes required ICU care, but no intubation was ever needed. Given the recurrent ICU admissions despite optimal pharmacotherapy for asthma, we have performed extensive investigations to exclude other diseases, including CT thorax, blood tests, echocardiogram and sleep study. During one of the ICU admissions, the patient was noted to have a low tidal and a high respiratory rate while on non-invasive pressure ventilation (NIV). Arterial blood gas taken during the ‘attacks’ showed respiratory acidosis with elevated pCO2 and normal alveolar-arterial gradient. The ‘attacks’ did not improve with asthma medications but responded to oxygen supplementation and NIV. We suspected ILO and were able to prove that by laryngoscopy. The patient had several ‘attacks’ of breathlessness afterwards, which were improved by benzodiazepines. We have thus stopped the unnecessary asthma medications for this patient, including biologics. The ILO was managed by speech therapist, psychologist, psychiatrist and ENT surgeon. Not every patient needs extensive investigations to search for comorbidities, but how far we need to go for patients with recurrent ‘asthma attacks’ would need clinical judgement and a personalized approach. Also, we have to think about ILO earlier in patients with severe asthma not responding well to therapy. We currently have potent medications, including biologics, for treating severe asthma, but we must ensure that these are given to the right patient. None declared.

Asynchrony During Pediatric Noninvasive Ventilation With a Nasal Cannula Interface: A Lung Model Study.

Pediatric noninvasive ventilation (NIV) is used commonly in the acute care setting and is associated with high incidence of patient ventilator asynchrony. An ASL 5000 breathing simulator was used to model pediatric patients with varying patient efforts and lung conditions. For delivery of NIV, a commonly used acute care ventilator was used by connecting a nasal cannula interface to model nares produced with a 3-dimensional printer. The modes of ventilation were NIV pressure control continuous mandatory ventilation and NIV pressure control continuous spontaneous ventilation. Patient and ventilator waveforms were analyzed using the ASL 5000 software to assess for asynchrony events and determine the asynchrony index (AI). Significant asynchrony (AI > 0.1) existed in the majority of scenarios for both pressure control continuous mandatory ventilation and pressure control continuous spontaneous ventilation (79% and 93%, respectively). The most common asynchrony event was ineffective trigger, accounting for 81.9% of events in pressure control continuous mandatory ventilation and 79.3% in pressure control continuous spontaneous ventilation. There were no statistically significant differences in the AI when comparing simulated patient effort or lung condition. Significant asynchrony exists during NIV with a commonly used acute care ventilator and nasal cannula interface, which raises questions regarding its utility in clinical practice in the pediatric population.

Impact of Interface Type on Noninvasive Ventilation Efficacy in Patients With Neuromuscular Disease: A Randomized Cross-Over Trial

Background and objectiveAround 25% of patients with neuro-muscular diseases (NMD) are treated by home noninvasive ventilation (NIV) through an oronasal mask. However, there is growing evidence that nasal masks require lower NIV pressures and result in fewer residual obstructive events. We hypothesized that nasal masks would improve efficacy and reduce side effects compared to oronasal masks in this population. Methodsopen label, cross-over, randomized, study in 2 tertiary care hospitals. Patients with NMD treated by home NIV were randomized for one-week periods to nasal and oronasal interfaces respectively (cross-over). At the end of each period, nocturnal polygraphy (monitoring mouth opening) under NIV, synchronized with transcutaneous partial pressure in CO2 (tcCO2) was performed. Data were collected from the NIV built-in software and NIV side-effects were collected. Intention-to-treat and per protocol analyses were performed. The primary outcome was mean nocturnal SpO2. The secondary outcomes were: percentage of sleep with SpO2<90%, oxygen desaturation index (ODI), mean tcCO2, mean duration of mouth opening during sleep, level of non-intentional leaks and side-effects. ResultsThirty patients with NMD were included. There were no between-group differences for either the primary or secondary outcomes. Post hoc comparisons showed that changing between interfaces reduced NIV efficacy: mean nocturnal SpO2 (p=0.04), ODI (p=0.01), mean tcCO2 (p=0.048), side-effects (p=0.008). ConclusionNasal masks did not improve NIV efficacy or reduce side effects compared to oronasal masks in patients with NMD treated by home NIV. The efficacy of NIV is reduced during the transition to another interface, requiring close monitoring.Registration number: NCT03458507.

Correction: Non-invasive ventilation with pursed lips breathing mode for patients with COPD and hypercapnic respiratory failure: A retrospective analysis

[This corrects the article DOI: 10.1371/journal.pone.0238619.].

Short-term usage of three non-invasive ventilation interfaces causes progressive discomfort in healthy adults

PurposeTo evaluate the effect of three different non-invasive ventilation (NIV) interfaces on the subjective discomfort of healthy individuals, and on a set of physiological parameters hypothesized to change in correspondence to discomfort.MethodsContinuous pressure NIV was applied to 20 subjects using Total Face, Nasal, and Face masks for 10 min each. Tidal volume (VT) and respiratory period (RP) were estimated from respiratory inductance plethysmography. Electrodermal activity was estimated from conductance signals. Heart rate variability was measured using the time-domain indices SDNN and RMSSD, and the respiratory sinus arrhythmia amplitude (RSAp). Parameters were referenced to 5-min rest periods at beginning and end of protocol. A Likert-like scale of subjective discomfort with the masks and the ventilation was applied after 1, 5, and 9 min using each mask.ResultsRP and VT increased with the three mask models. Whereas the mean heart rate and RSAp did not change, both SDNN and RMSSD increased during NIV with Nasal and Face masks. Spontaneous electrodermal activity fluctuations were less frequent during NIV than at rest, with significant differences for Total Face and Nasal masks. Discomfort with all masks increased from minutes 1 to 9, markedly in the Total Face mask, considered most uncomfortable by 11 subjects.ConclusionIn healthy subjects, the three masks resulted in similar respiratory responses to NIV. Correspondence between changes in physiological parameters and discomfort with NIV interface could not be detected, whereas self-report with the Likert-like scale identified progressive discomfort and the Total Face mask as the most uncomfortable interface.Supplementary InformationThe online version contains supplementary material available at 10.1007/s42600-020-00114-3.

Nasal Continuous Positive Airway Pressure (NCPAP) Vs&amp;nbsp;Noninvasive Positive Pressure Ventilation (NIPPV) vs&amp;nbsp;Noninvasive High Frequencyoscillation Ventilation (NHFOV) as Post-Extubation Support in Preterm Neonates: A Multi-Center, Randomised, Assessor-Blinded Controlled Trial

Nasal Continuous Positive Airway Pressure (NCPAP) Vs&amp;nbsp;Noninvasive Positive Pressure Ventilation (NIPPV) vs&amp;nbsp;Noninvasive High Frequencyoscillation Ventilation (NHFOV) as Post-Extubation Support in Preterm Neonates: A Multi-Center, Randomised, Assessor-Blinded Controlled Trial

Non-invasive ventilation with pursed lips breathing mode for patients with COPD and hypercapnic respiratory failure: A retrospective analysis.

Long-term non-invasive ventilation (NIV) is recommended for patients with stable chronic obstructive lung disease (COPD) and chronic hypercapnia. High inspiratory pressure NIV (hiNIV) and a significant reduction of arterial pCO2 have been shown to prolong survival. Often, patients on hiNIV describe severe respiratory distress, known as "deventilation syndrome", after removal of the NIV mask in the morning. Mechanical pursed lips breathing ventilation (PLBV) is a new non-invasive ventilation mode that mimics the pressure-curve of pursed lips breathing during expiration. The clinical impact of switching patients from standard NIV to PLBV has not been studied so far. In this hypothesis generating study, we retrospectively analysed the effects of switching COPD patients (stage GOLD III-IV) from conventional NIV to PLBV. Medical records of all patients who had an established NIV and were switched to PLBV between March 2016 and October 2017 were screened. Patients were included if they complained of shortness of breath on mask removal, used their conventional NIV regularly, and had a documented complete diagnostic workup including lung function testing, blood gas analysis and 6-minute walk test (6MWT) before and after 3-7 days of PLBV. Six male and 10 female patients (median age 65.4 years; IQR 64.0-71.3) with a previous NIV treatment duration of 38 months (median; IQR 20-42) were analysed. After PLVB initiation, the median inspiratory ventilation pressure needed to maintain the capillary pre-switch pCO2 level was reduced from 19.5 mbar (IQR 16.0-26.0) to 13.8 mbar (IQR 12.5-14.9; p<0.001). The median 6MWT distance increased from 200m (IQR 153.8-266.3) to 270m (IQR 211.3-323.8; p<0.001). Median forced vital capacity (FVC) increased from 49.5% to 53.0% of the predicted value (p = 0.04), while changes in FEV1 and residual volume (RV) were non-significant. Based on this small retrospective analysis, we hypothesise that switching patients with COPD GOLD III-IV and chronic hypercapnia from conventional NIV to PLBV may increase exercise tolerance and FVC in the short term.

Impact of Interface Type on Noninvasive Ventilation Efficacy in Patients With Neuromuscular Disease: A Randomized Cross-Over Trial

Background and objectiveAround 25% of patients with neuro-muscular diseases (NMD) are treated by home noninvasive ventilation (NIV) through an oronasal mask. However, there is growing evidence that nasal masks require lower NIV pressures and result in fewer residual obstructive events. We hypothesized that nasal masks would improve efficacy and reduce side effects compared to oronasal masks in this population. Methodsopen label, cross-over, randomized, study in 2 tertiary care hospitals. Patients with NMD treated by home NIV were randomized for one-week periods to nasal and oronasal interfaces respectively (cross-over). At the end of each period, nocturnal polygraphy (monitoring mouth opening) under NIV, synchronized with transcutaneous partial pressure in CO2 (tcCO2) was performed. Data were collected from the NIV built-in software and NIV side-effects were collected. Intention-to-treat and per protocol analyses were performed. The primary outcome was mean nocturnal SpO2. The secondary outcomes were: percentage of sleep with SpO2<90%, oxygen desaturation index (ODI), mean tcCO2, mean duration of mouth opening during sleep, level of non-intentional leaks and side-effects. ResultsThirty patients with NMD were included. There were no between-group differences for either the primary or secondary outcomes. Post hoc comparisons showed that changing between interfaces reduced NIV efficacy: mean nocturnal SpO2 (p=0.04), ODI (p=0.01), mean tcCO2 (p=0.048), side-effects (p=0.008). ConclusionNasal masks did not improve NIV efficacy or reduce side effects compared to oronasal masks in patients with NMD treated by home NIV. The efficacy of NIV is reduced during the transition to another interface, requiring close monitoring.Registration number: NCT03458507.

Extracorporeal membrane oxygenation for severe acute respiratory distress syndrome caused by novel 2009 influenza A (H1N1) virus

To summarize the clinical experiences and indications of extracorporeal membrane oxygenation (ECMO) for severe ARDS caused by novel 2009 influenza A (H1N1) virus. All ECMO cases with severe ARDS associated with novel 2009 influenza A (H1N1) virus were analyzed in 5 intensive care units (ICUs) from 5 different hospitals in Beijing and Tianjin. A physician experienced in ECMO handling collected the relevant data, including general conditions pre and post-EMCO, efficacy and complication parameters, ventilator settings of mechanical ventilation and clinical outcomes. The statistical software of SPSS (version 11.5) was used for data analysis. 18 cases of novel H1N1 influenza with severe ARDS received ECMO. There were 9 males and 9 females (all pregnant). The mean age was (33 ± 11) years old. Eight were complicated with pulmonary barotraumas (6 of pneumothorax). Prior to ECMO, the patients underwent noninvasive and invasive positive pressure ventilation for 1 day and 60 hours respectively. Physiological parameters 2-6 hours prior to ECMO use were: (53 ± 14) mm Hg of PaO2/FiO2, (17 ± 5) cm H2O of positive end expiratory pressure (PEEP), 3.80 ± 0.29 of Murray lung injury score, (7.38 ± 0.10) of arterial pH, (3.3 ± 2.3) mmol/L of serum lactate, 16 ± 8 of APACHE II score. All patients treated venous-venous ECMO (VV-ECMO) for a mean duration of 8 days (range: 2 - 168). Settings of mechanical ventilation (prior to ECMO vs 2 hours post-ECMO) were: peak airway pressure (31 ± 7) vs (25 ± 6) cm H2O, respiratory rate (15 ± 4) vs (22 ± 6) breaths/min, FiO2 0.8 - 1.0 vs 0.35 - 0.50, PEEP (16 ± 5) vs (12 ± 4) cm H2O. Arterial blood gas (pH, PaO2 and PaCO2) post-ECMO of 2 hours and 24-hour significantly improved (P < 0.05). Seven patients died during ECMO, 11 patients were successfully weaned from ECMO. And 8 of them survived and were discharged. One patient stayed in ICU and 2 died in ICU. As an effective measure of respiratory supports, ECMO may provide pulmonary rest and improve gas exchanges in severe ARDS induced by novel H1N1 Influenza.

Transnasal high flow oxygen therapy combined with noninvasive positive pressure ventilation Chronic obstructive pulmonary disease with respiratory failure patient outcomes

Objective To investigate the effect of Nasal high-flow oxygen therapy combined with noninvasive positive pressure ventilation on COPD patients with respiratory failure and the effects on the levels of PaO2, PaCO2 and SaO2. Methods A total of 126 patients with COPD complicated with respiratory failure who were admitted from January 2017 to June 2019, including 69 males and 57 females, aged(58.94±5.89)years and ranging in age from 45 to 76 years, were randomly divided into NPPV group and HFNC group by random number table method, with 63 cases in each group.Patients in the NPPV group were given NPPV, while HFNC group was given HFNC on the basis of NPPV group.The clinical treatment effect and complications of the two groups were compared 48 h after treatment, and the changes in blood oxygen partial pressure, blood carbon dioxide partial pressure, blood oxygen saturation level, heart rate, respiratory rate and sputum viscosity of the two groups before and after treatment were compared. Results After treatment, the effective rate of HFNC group[95.2%(60/63)]was higher than that of NPPV group[82.6%(52/63)]. HFNC group had higher blood oxygen partial pressure[(87.87±9.45)mmHg, 1 mmHg=0.133 kPa]and blood oxygen saturation[(89.29±8.99)%]than NPPV group[(78.43±8.69)mmHg and(82.21±8.20)%], and lower blood carbon dioxide partial pressure[(47.95±4.85)mmHg]than NPPV group[(56.72±5.19)mmHg]. HFNC group had lower heart rate[(85.45±4.38)times/minute]and respiratory rate[(18.39±2.03)times/minute]than NPPV group[(92.87±4.72)times/minute, [22.49±2.52)times/minute]than NPPV group, with statistically significant differences(P<0.05). Conclusion HFNC combined with NPPV in the treatment of COPD patients with respiratory failure has a good clinical treatment effect, which can improve the levels of PaO2, PaCO2 and SaO2 and reduce the viscosity of sputum, which is worthy of clinical application. Key words: Nasal high-flow oxygen therapy; Noninvasive positive pressure ventilation; COPD combined with respiratory failure; PaO2; PaCO2; Oxygen saturation

Effect of NIPPV in the treatment of AECOPD complicated with type II respiratory failure and its influence on blood gas index

Objective To investigate the effect of noninvasive positive pressure ventilation(NIPPV) in the treatment of patients with acute exacerbation of chronic obstructive pulmonary disease(AECOPD) complicated with type Ⅱ respiratory failure and its influence on blood gas index. Methods From August 2014 to December 2016, the clinical data of 79 patients with AECOPD complicated with type Ⅱ respiratory failure in the Central Hospital of Shanxi Coal were retrospectively analyzed.The patients were divided into two groups according to different treatment methods.Thirty-five patients in the control group were treated with conventional therapy, 44 patients in the observation group were treated with conventional NIPPV.The blood gas index, nutritional index, plasma N-terminal brain natriuretic peptide precursor(NT-proBNP), lactate(Lac) and the changes of procalcitonin (PCT), soluble myeloid cell trigger receptor-1(sTREM-1) level were compared between the two groups. Results There were no statistically significant differences in respiratory frequency, blood gas index and APACHE Ⅱ score between the two groups before treatment(P=0.282, 0.177, 0.485, 0.472, 0.485). The levels of pH (7.41±0.07) and PaO2[(82.30±6.99)mmHg]in the observation group were higher than those in the control group(t=9.357, 5.328, P=0.000, 0.000). The respiratory frequency[(20.02±2.15)times/min], PaCO2[(52.36±5.15)mmHg]and APACHE Ⅱ score[(18.20±1.01)points]in the observation group were lower than those in the control group(t=7.782, 10.608, 9.360, P=0.000, 0.000, 0.000). There were no statistically significant differences between the two groups in the levels of nutritional indicators before treatment(t=0.027, 0.039, 0.068, P=0.488, 0.485, 0.473). After treatment, the serum total protein level in the observation group was higher than that in the control group, but the levels of serum albumin and hemoglobin had no statistically significant differences compared with those in the control group(t=3.606, 1.659, 0.034, P=0.000, 0.051, 0.486). There were no statistically significant differences in the levels of Lac, NT-proBNP, inflammatory factors between the two groups before treatment(P=0.465, 0.477, 0.451, 0.493). The levels of Lac[(1.57±0.55)mmol/L], NT-proBNP[(130.25±42.36)ng/L], PCT[(0.16 ±0.09)g/L], sTREM-1[(66.36±12.87)ng/L]in the observation group were lower than those in the control group(t=7.662, 2.248, 4.030, 2.709, P=0.000, 0.014, 0.000, 0.004). After treatment, the respiratory rate, blood gas index and APACHE Ⅱ score of the two groups were improved compared with those of the control group(all P 0.05). Conclusion NIPPV in the treatment of AECOPD complicated with type Ⅱ respiratory failure can effectively improve the blood gas status and nutritional status of patients, and reduce the body Lac and NT-proBNP levels. Key words: Positive-pressure respiration; Ventilators, mechanical; Pulmonary disease, chronic Obstructive; Respiratory insufficiency; Blood gas analysis; Nutrition assessment; Natriuretic peptide, brain; Procalcitonin; Lactic acid

Comparison of clinical treatment of traumatic cervical spinal cord injuries with acute respiratory failure treated by high-flow nasal cannula therapy and non-invasive positive pressure ventilation

Objective To compare the clinical efficacy of high-flow nasal cannula oxygen therapy (HFNC) with non-invasive positive pressure ventilation (NPPV) in patients with traumatic cervical spinal cord injury complicated with acute respiratory failure (ARF). Methods A prospective randomized controlled trial was performed in EICU of the First Affiliated Hospital of Zhengzhou University from May 2016 to January 2018. One hundred sixty-eight consecutive patients with traumatic cervical spinal cord injury complicated with ARF, who did not respond to conventional oxygen therapy, were assigned to the HFNC or NPPV treatment group sequenced by the random number table. The baseline clinical characteristics of randomized participants and respiratory frequency (RR), PaCO2, mean arterial pressure (MAP) at 1, 12, 24, 48 h after treatment were evaluated. Comfortable scale, tracheal intubation rate within 28 d, duration of mechanical ventilation, length of stay in ICU and mortality rate were compared as well. Results There was no significant differences in baseline clinical characteristics, such as sex, age. between the two groups (P>0.05). RR and PaCO2 were lower in the HFNC group at all time point. In addition, the HFNC group had significantly lower PaCO2 than the NPPV group at 24 and 48 h after treatment (P 0.05). Conclusions In addition to the superior efficacy in improving respiratory function and shortening length of stay in ICU, HFNC was well tolerated by patients with traumatic cervical spinal cord injury complicated with ARF, and could be recommended in clinical practice. Key words: Traumatic cervical spinal cord injury; High-flow nasal cannula oxygen therapy; Non-invasive positive pressure ventilation; Respiratory failure

Effects of propofol and midazolam on the prognosis of patients treated with noninvasive positive pressure ventilation

Objective To compare the effects of propofol and midazolam on the prognosis of patients treated with noninvasive positive pressure ventilation. Methods A prospective, single-blind, randomized controlled trial(RCT) was conducted in 90 patients who were treated with noninvasive ventilation for acute dyspnea in the ICU of the Sixth People′s Hospital Affiliated to Shanghai Jiaotong University from October 2014 to December 2016.They were randomly divided into three groups according to the digital table, with 30 cases in each group.The control group was not given sedation treatment.The propofol group was given propofol 0.5~1 mg/kg, and then administered by intravenous infusion of 1 mg·kg-1·h-1 with a micropump.The midazolam group was given midazolam 0.05-0.1mg/kg, and then with intravenous infusion of 0.05-0.1 mg·kg-1·h-1 maintaining the patients' sedation goals(Ramsay score of 2). The vital signs and blood gas analysis indicators were recorded.The incidence of tracheal intubation, the incidence of hospital infection, length of ICU and hospital stay, mortality and sedation-related complications were compared. Results The tracheal intubation rate in the propofol group was similar to that in the midazolam group(20.0% vs.23.3%, χ2=2.65, P>0.05), while the tracheal intubation rate(46.7%) in the control group was significantly higher(χ2=4.21, 4.17, all P 0.05). The incidence rates of hospital infection in the propofol group and midazolam group were 6.6%(2 cases) and 10.0%(3 cases), which were significantly lower than 33.3%(10 cases) in the control group (χ2=4.32, 4.23, all P<0.05). Conclusion The use of mild sedation in patients of acute dyspnea treated with noninvasive positive pressure ventilation can improve the patients' tolerance rate, reduce the rate of tracheal intubation and the incidence of hospital infection, and decrease the length of ICU and hospital stay, without significant adverse reactions.There was no significant difference between propofol and midazolam. Key words: Propofol; Midazolam; Sedation; Continuous positive airway pressure; Respiration, artificial; Dyspnea; Cross infection; Prognosis; Comparative effectiveness research

Obstructive sleep apnea syndrome in the pediatric age: the role of the pneumologist.

This review paper aims to summarize the current state of knowledge on the role of the pneumologist in the diagnosis and respiratory treatment of children affected by obstructive Sleep Disordered Breathing (SDB). A literature review has been performed on the following topics: obstructive SDB and its clinical entities, indications for respiratory treatment of pediatric SDB, and Continuous Positive Airway Pressure (CPAP) and Noninvasive Positive Pressure Ventilation (NIPPV) treatment approach to obstructive SDB. OSDB is related to obesity, craniofacial pathologies, neuromuscular disorders and, most commonly, oadenotonsillar hypertrophy. Adenotonsillectomy is the first-choice treatment in children with obstructive apnea secondary to adenotonsillar hypertrophy. CPAP and NIPPV are recommended in cases where Obstructive Sleep Apnea (OSA) persists after surgery or when surgery is contraindicated. Treatment interventions are usually implemented gradually by separately addressing each abnormality that would predispose to obstructive SDB, then reevaluating after each intervention to detect any residual disease and to assess the need for additional treatment. Many pediatric patients continue to experience problems and symptoms such as hypersomnia and apnea after adenotonsillectomy and need CPAP/NIPPV treatment. Current knowledge is still incomplete, especially with regard to the mechanisms of pathogenesis of pediatric OSA, the factors affecting pediatric OSA, and the phenotypic variability of the disease. A better understanding of these aspects would contribute to the development of new therapies.

New modalities for non-invasive positive pressure ventilation: A review article.

Efficiency of non-invasive positive pressure ventilation in the treatment of respiratory failure has been shown in many published studies. In this review article, we introduced new modalities of non-invasive ventilation (NIV), clinical settings in which NIV can be used and a practical summary of the latest official guidelines published by the European Respiratory Clinical Practice. Clinical trials and review articles in four databases up to 25 February 2018 about new modalities of non-invasive positive pressure ventilation were reviewed. Commonly used modalities for treatment of respiratory failure include: CPAP (continuous positive airway pressure) and BiPAP (bilevel positive airway pressure) or NIPSV (noninvasive pressure support ventilation). The limitations of the BiPAP method are the trigger and cycle asynchrony, inadequate volume delivery and increased respiratory rate. Newer methods, such as adaptive servo-ventilation, have been developed to treat central and complex sleep apnea and the NAVA (neutrally adjusted ventilatory assist) to improve the trigger and cycle asynchrony. In the proportional assist ventilation, unlike the pressure support ventilation, with increased patient effort (flow) the tidal volume increases and it prevents the increase in the respiratory rate and respiratory distress. High-flow nasal cannula is a non-invasive technique that does not provide respiratory support, but provides a mixture of oxygen to the patient. The use of non-invasive pursed-lip breathing ventilation in chronic obstructive pulmonary disease (COPD) patients reduces dyspnea (decreases respiratory rate) and increases blood oxygen saturation. New modalities of NIV improve patient comfort and patient–ventilator interactions, and are recommended in patients with respiratory failure.

Efficacy and troubleshooting of noninvasive ventilation

Noninvasive positive pressure ventilation (NPPV) means application of ventilation through patient’s upper airway by an interface without an endotracheal tubeortracheostomy. The efficacy of NPPV depends on the selection of equipment and interface, good clinician experience,and meticulous monitoring during NPPV. Several interfaces are available with nasal and oronasal types are the most common. The most common troubleshooting of NPPV are leak, CO2 rebreathing, mask problems, and asynchrony.

Influencing factors of compliance with home non-invasive positive pressure ventilation treatment in children

Non-invasive positive pressure ventilation(NPPV)can avoid upper respiratory tract trauma due to tracheotomy and reduce iatrogenic infection as well as minimize the pain of the patients.NPPV therapy has been increasingly developed in congenital and secondary disordered breathing diseases such as neuromuscular diseases, craniofacial malformation, obstructive sleep apnea hypopnea syndrome and other aliments.Though this therapy method is available and effective, the compliance with home NPPV treatment is relatively low.Various factors can influence adhe-rence of NPPV therapy.Individual and family factors are associated with compliance with NPPV, such as the patient′s age, inherited metabolic diseases, family economic status and educational level of the main caretakers.The structure of ventilator along with physician-patient communication also affect the treatment compliance.Now, the influencing factors of compliance with home NPPV treatment in children were reviewed. Key words: Child; Non-invasive positive pressure ventilation; Compliance; Influencing factor

Abstract P-581: NON-INVASIVE VENTILATION WITH NASAL-PHARYNGEAL TUBE IN LIMITED RESOURCE: CASE SERIES

Aims & Objectives: Use of non-invasive ventilation (NIV) has increased in past years. Successful NIV requires compatible interface, however, NIV masks have not been widely available in our country so we tried alternative interface, albeit less effective because of potential leakage. Methods Case series Results Case 1. A 3-months-old baby, 3.6kg, was admitted with respiratory failure, pneumonia, and large PDA. She was intubated for 8 days then switched to NIV–pressure control (PC) mode (Servo-i) with ET tube 3.0 inserted 8 cm from nostril, respiratory rate (RR) 30x/minute, FiO2 40%, PIP 15/PEEP 6. Minute volume (MV) 0.6–0.9 L, PaO2 108.8, and PaCO2 32.7 were achieved without increased work of breathing. Case 2. A 4-months-old boy, 7.6kg, was admitted with pneumonia and respiratory failure. He had diaphoresis, chest indrawing, SaO2 90%, PaO2 33.2, and PaCO2 59.7, with 6 lpm oxygen (PaO2/FiO2 ratio 83). NIV–PC mode was started with ET tube 3.5 inserted 9 cm from nostril, RR 20x/minute, FiO2 65%, PIP 15/PEEP 5. His work of breathing was reduced significantly after NIV, RR was decreased from 60 to 30x/minute, and SaO2 was improved. Case 3. A 3.5-years-old boy, 15kg, admitted with dilated cardiomyopathy, cardiogenic shock, and increased work of breathing on 1 lpm nasal oxygen. NIV–PC was administered using ET tube 4.0, 12 cm depth, RR 30x/minute, FiO2 40%, PIP 15/PEEP 5. Chest wall retraction was diminished after NIV. Conclusions Despite of our limited resource, NIV showed promising results in respiratory failure and prevention of reintubation. Shortened ET tube might be used as alternative interface in pediatric NIV.