Noninvasive Ventilation Interfaces in the Treatment of Acute Respiratory Insufficiency: A Critical Review

Background: Noninvasive ventilation (NIV) is an important therapeutic modality for the treatment of acute respiratory failure (ARF). In this review, we critically analyze randomized controlled trials on the most used NIV interfaces in the treatments of ARF. Methods: The searches were conducted in the Medline, Lilacs, PubMed, Cochrane, and Pedro databases from June to November 2021. The inclusion criteria were Randomized clinical trials (RCTs) published from 2016 to 2021 in Portuguese, Spanish, or English and involving adults (aged ≥ 18 years). The eligibility criteria for article selection were based on the PICO strategy: Population—Adults with ARF;Intervention—NIV Therapy;Comparison—Conventional oxygen therapy, high-flow nasal cannula (HFNC) oxygen therapy, or NIV;Outcome—improvement in ARF. The search for articles and the implementation of the inclusion criteria were independently conducted by two researchers. Results: Seven scientific articles involving 574 adults with ARF due to various causes, such as chest trauma, decompensated heart failure, coronavirus disease 2019 (COVID-19), and postoperative period, among others, were included. The interfaces cited in the studies included an oronasal mask, nasal mask, full-face mask, and helmet. In addition, some favorable outcomes related to NIV were reported in the studies, such as a reduction in the rate of orotracheal intubation and shorter length of stay in the ICU. Conclusions: The most cited interfaces in the treatment of ARF were the oronasal mask and the helmet.

High-flow nasal cannula oxygen therapy and noninvasive ventilation for preventing extubation failure during weaning from mechanical ventilation assessed by lung ultrasound score: A single-center randomized study

BACKGROUND: We sought to demonstrate the superiority of a targeted therapy strategy involving high-flow nasal cannula oxygen(HFNCO_(2)) therapy and noninvasive ventilation(NIV) using lung ultrasound score(LUS) in comparison with standard care among patients in the intensive care unit(ICU) who undergo successful weaning to decrease the incidence of extubation failure at both 48 hours and seven days.METHODS: During the study period, 98 patients were enrolled in the study, including 49 in the control group and 49 in the treatment group. Patients in the control group and patients with an LUS score <14 points(at low risk of extubation failure) in the treatment group were extubated and received standard preventive care without NIV or HFNCO_(2). Patients with an LUS score ≥14 points(at high risk of extubation failure) in the treatment group were extubated with a second review of the therapeutic optimization to identify and address any persisting risk factors for postextubation respiratory distress;patients received HFNCO2 therapy combined with sessions of preventive NIV(4-8 hours per day for 4-8 sessions total) for the first 48 hours after extubation.RESULTS: In the control group, 13 patients had the LUS scores ≥14 points, while 36 patients had scores <14 points. In the treatment group, 16 patients had the LUS scores ≥14 points, while 33 patients had scores <14 points. Among patients with the LUS score ≥14 points, the extubation failure rate within 48 hours was 30.8% in the control group and 12.5% in the treatment group, constituting a statistically significant difference(P<0.05). Conversely, among patients with an LUS score <14 points, 13.9% in the control group and 9.1% in the treatment group experienced extubation failure(P=0.61). The length of ICU stay(9.4±3.1 days vs. 7.2±2.4 days) was significantly different and the re-intubation rate(at 48 hours: 18.4% vs. 10.2%;seven days: 22.4% vs. 12.2%) significantly varied between the two groups(P<0.05). There was no significant difference in the 28-day mortality rate(6.1% vs. 8.2%) between the control and treatment groups.CONCLUSIONS: Among high-risk adults being weaned from mechanical ventilation and assessed by LUS, the NIV+HFNCO_(2) protocol does not lessen the mortality rate but reduce the length of ICU stay, the rate of extubation failure at both 48 hours and seven days.

Helmet-based noninvasive ventilation for acute exacerbation of chronic obstructive pulmonary disease: A case report

BACKGROUND Noninvasive ventilation(NIV)reduces intubation rates,mortalities,and lengths of hospital and intensive care unit stays in patients with acute exacerbation of chronic obstructive pulmonary disease(AECOPD).Helmet-based NIV is better tolerated than oronasal mask-based ventilation,and thus,allows NIV to be conducted for prolonged periods at higher pressures with minimal air leaks.CASE SUMMARY A 73-year-old man with a previous diagnosis of COPD stage 4 was admitted to our medical intensive care unit with chief complaints of cough,sputum,and dyspnea of several days’duration.For 10 mo,he had been on oxygen at home by day and had used an oronasal mask-based NIV at night.At intensive care unit admission,he breathed using respiratory accessory muscles.Hypercapnia and signs of infection were detected,and infiltration was observed in the right lower lung field by chest radiography.Thus,we diagnosed AECOPD by communityacquired pneumonia.After admission,respiratory distress steadily deteriorated and invasive mechanical ventilation became necessary.However,the patient refused this option,and thus,we selected helmet-based NIV as a salvage treatment.After 3 d of helmet-based NIV,his consciousness level and hypercapnia recovered to his pre-hospitalization level.CONCLUSION Helmet-based NIV could be considered as a salvage treatment when AECOPD patients refuse invasive mechanical ventilation and oronasal mask-based NIV is ineffective.

Noninvasive ventilation in cancer children with acute respiratory failure

Objective: To establish the effectiveness of noninvasive ventilation in cancer children with acute respiratory failure. <br> Methods: The data of 33 cancer patients were obtained prospectively from six different pediatric intensive care units in Turkey between the years of 2012 and 2013. <br> Results: The diagnosis was leukemias in 25 (75.8%), lymphomas in 3 (9.1%) and other solid tumors in 5 (15.1%) patients. Pneumonia in 12 (36.3%) and sepsis in 15 (45.4%) patients were seen as the common reasons of respiratory failure. The mean PaO2/FiO2 ratios were (164.22 ± 37.24) and (126.80 ± 42.73) in noninvasive ventilation success and failure group, respectively. Noninvasive ventilation was successful in 18 (54.5%) patients. The failure group consisted of 15 patients required intubation. A total of 14 (42.4%) patients died. The clinical outcome in terms of success and failure was meaningful statistically (P = 0.0 00 1). <br> Conclusions: Our results could encourage the use of noninvasive ventilation in children with cancer who develop acute respiratory failure. It should be considered as a useful therapeutic approach to avoid endotracheal intubation.

Analysis of the Effect of Extracorporeal Diaphragmatic Pacing Combined with Noninvasive Ventilator on the Respiratory Function and Prognosis of COPD Patients

Objective: To investigate the effect of extracorporeal diaphragmatic pacing combined with noninvasive ventilators on the respiratory function and prognosis of chronic obstructive pulmonary disease (COPD) patients. Methods: A total of 50 COPD patients were selected between January 2023 to December 2023 and randomly grouped into an observation group and a control group, with 25 cases. The observation group was given extracorporeal diaphragm pacing combined with a noninvasive ventilator, while the control group was given a conventional treatment mode. After the treatment, the results of each index in the two groups were compared. Results: Compared with the diaphragm function indexes of the two groups, the data of the observation group were more dominant (P < 0.05). The rehospitalization rate of the observation group was lower than that of the control group (P < 0.05). The COPD assessment test (CAT) and mMRC (Modified Medical Research Council) Dyspnoea scale scores after treatment between the two groups were significantly different (P < 0.05). Compared with the control group, the lung function indexes of the observation group were more dominant (P < 0.05). Conclusion: Extracorporeal diaphragmatic pacing combined with a noninvasive ventilator promoted the improvement of the patient’s prognosis and improved their respiratory function.

Noninvasive ventilation for pediatric interfacility transports:a retrospective study

Background To characterize pediatric patients supported with continuous positive airway pressure and bilevel positive airway pressure(CPAP/BiPAP)or high-flow nasal cannula(HFNC)during interfacility transport(IFT).Methods A retrospective study with a provincial pediatric transport team from a tertiary hospital pediatric intensive care unit.Pediatric patients aged 28 days to<17 years,who required IFT between January 2017 and December 2018,were identified through a transport registry and were included in the study.Results A total of 118(26.7%)patients received CPAP/BIPAP or HFNC support for IFT.The most common respiratory diagnosis was bronchiolitis(46%).These patients were placed on respiratory support,31.4 minutes after the transport team’s arrival.None required intubation during their IFT,despite mean transport times of 163 minutes.Conclusions This study may provide important information for programs with large catchment areas,in which large distances and transport times should not be barriers to NIV implementation.

Impact of noninvasive positive pressure ventilation on the gene expression of ubiquitin system of skeletal muscle in patients with acute exacerbation of chronic obstructive pulmonary disease

Objective:To investigate the change and relativity of noninvasive positive pressure ventilation(NIPPV)on the gene expression of ubiquitin system of skeletal muscle in patient with acute exacerbation of chronic obstructive pulmonary disease(AECOPD).Methods:80 patients with AECOPD were divided into two groups based on whether the NIPPV treatment was given or not,38 cases in the study group and 42 in the control group.The blood gas analysis and pulmonary function were monitored and recorded before and 14 days after treatment.A skeletal muscle biopsy was performed 14 days after therapy.The mRNA expression of ribosomal protein S21(RPS21)and ubiquitin in skeletal muscle cell were measured by RT-PCR.Results:After 14 days treatment,the levels of PaCO_(2),PaO_(2),PH and FEV_(1)% in the NIPPV group improved much better than in the control group(p<.05).The gene expression of RPS21 and ubiquitin was obviously lower in the study group than in the control group(p<.05).The level of RPS21 was negatively related with PaO_(2),PH and FEV1%,and the level of ubiquitin was negatively related with PaO_(2) and FEV1%,but positively correlated with PaCO_(2).The area under the ROC curves of RPS21,ubiquitin,PaCO_(2) and FEV_(1)% were 0.771,0.885,0.821 and 0.734 respectively in the study group.The cut-off points were 103.978,8.128,45.350 and 51.350 respectively.The sensitivity evaluation of acid poisoning was 90.9%,and the specificities for each were 75%,75%,50% and 50%.Conclusions:NIPPV is effective for AECOPD patients through the gene expression of ubiquitin system of skeletal muscle.

Importance of proper ventilator support and pulmonary rehabilitation in obese patients with heart failure:Two case reports

BACKGROUND The optimal treatment for heart failure(HF)is a combination of appropriate medications.Controlling the disease using only medical therapy is difficult in patients with HF,severe hypercapnia,and desaturation.These patients should first receive ventilator support followed by pulmonary rehabilitation(PR).CASE SUMMARY We report two cases in which arterial blood gas(ABG)improved and PR was possible with appropriate ventilator support.Two patients with extreme obesity complaining of worsening dyspnea–a 47-year-old woman and a 36-year-old man both diagnosed with HF–were hospitalized because of severe hypercapnia and hypoxia.Despite proper medical treatment,hypercapnia and desaturation resolved in neither case,and both patients were transferred to the rehabilitation department for PR.At the time of the first consultation,the patients were bedridden because of dyspnea.Oxygen demand was successfully reduced once noninvasive ventilation was initiated.As the patients’dyspnea gradually improved to the point where they could be weaned off the ventilator during the daytime,they started engaging in functional training and aerobic exercise.After 4 mo of followup,both patients were able to perform activities of daily living and maintain their lower body weight and normalized ABG levels.CONCLUSION Symptoms of patients with obesity and HF may improve once ABG levels are normalized through ventilator support and implementation of PR.

Clinical study of NFNC in the treatment of acute exacerbation chronic obstructive pulmonary disease patients with respiratory failure

BACKGROUND Most patients with acute exacerbation chronic obstructive pulmonary disease(AECOPD)have respiratory failure that necessitates active correction and the improvement of oxygenation is particularly important during treatment.High flow nasal cannula(HFNC)oxygen therapy is a non-invasive respiratory aid that is widely used in the clinic that improves oxygenation state,reduces dead space ventilation and breathing effort,protects the loss of cilia in the airways,and improves patient comfort.AIM To compare HFNC and non-invasive positive pressure ventilation in the treatment of patients with AECOPD.METHODS Eighty AECOPD patients were included in the study.The patients were in the intensive care department of our hospital from October 2019 to October 2021.The patients were divided into the control and treatment groups according to the different treatment methods with 40 patients in each group.Differences in patient comfort,blood gas analysis and infection indices were analyzed between the two groups.RESULTS After treatment,symptoms including nasal,throat and chest discomfort were significantly lower in the treatment group compared to the control group on the 3rd and 5th days(P<0.05).Before treatment,the PaO_(2),PaO_(2)/FiO_(2),PaCO_(2),and SaO_(2)in the two groups of patients were not significantly different(P>0.05).After treatment,the same indicators were significantly improved in both patient groups but had improved more in the treatment group compared to the control group(P<0.05).After treatment,the white blood cell count,and the levels of C-reactive protein and calcitonin in patients in the treatment group were significantly higher compared to patients in the control group(P<0.05).CONCLUSION HFNC treatment can improve the ventilation of AECOPD patients whilst also improving patient comfort,and reducing complications.HFNC is a clinically valuable technique for the treatment of AECOPD.

Respiratory evaluation of patients requiring ventilator support due to acute respiratory failure

This review, based on relevant published evidence and the authors` clinical experience, presents how to evaluate a patient with acute respiratory failure requiring ventilatory support. This patient must be carefully evaluated by nurses, physiotherapists, respiratory care practitioners and physicians regarding the elucidation of the cause of the acute episode of respiratory failure by means of physical examination with the measurement of respiratory parameters and assessment of arterial blood gases analysis to make a correct respiratory diagnosis. After the initial evaluation, the patient must quickly receive adequate oxygen and ventilatory support that has to be carefully monitored until its discontinuation. When available, a noninvasive ventilation trial must be done in patients presenting desaturation during oxygen mask and or PaCO2 retention, especially in cases of cardiogenic pulmonary edema and severe exacerbation of chronic obstructive pulmonary disease. In cases of noninvasive ventilation trial-failure, endotracheal intubation and invasive protective mechanical ventilation must be promptly initiated. In severe ARDS patients, low tidal ventilation, higher PEEP levels, prone positioning and recruitment maneuvers with adequate PEEP titration should be used. Recently, new modes of ventilation should allow a better patient-ventilator interaction or synchrony permitting a sufficient unloading of respiratory muscles and increase patient comfort. Patients with chronic obstructive pulmonary disease may be considered for a trial for early extubation to noninvasive positive pressure ventilation in centers with extensive experience in noninvasive positive pressure ventilation.

Respiratory failure after scoliosis correction surgery in patients with Prader-Willi syndrome: Two case reports

BACKGROUND Sleep-disordered breathing,including hypoventilation and obstructive sleep apnea,is often observed in Prader-Willi syndrome(PWS).Particularly in adolescence,scoliosis causes a progressive restrictive pulmonary pattern,leading to hypoventilation,so timely corrective surgery is required.However,the effect is controversial.In addition,since mental retardation of PWS,patient effort-based respiratory tests may be less reliable.So far,no studies have accurately reported on the comparison of respiratory function before and after corrective surgery,and appropriate respiratory function measurement method in PWS.CASE SUMMARY We present two cases of adolescent PWS with typical characteristics,including obesity,mental retardation,and scoliosis.Two boys,aged 12 and 13,diagnosed with PWS,both underwent scoliosis correction surgery.Before and immediately after surgery,arterial blood tests showed no abnormalities and no respiratory symptoms occurred.However,after 6-7 mo,both patients complained of daytime sleepiness,difficulty sleeping at night,dyspnea on exertion,and showed cyanosis.Hypercapnia and hypoxia were confirmed by polysomnography and transcutaneous CO2 monitoring during sleep and were diagnosed with obstructive sleep apnea and alveolar hypoventilation.It was corrected by nighttime noninvasive ventilation application and normal findings of arterial blood gas were maintained after 6-8 mo follow-up.CONCLUSION Even after scoliosis surgery,“periodic”monitoring of respiratory failure with an“objective”test method is needed for timely respiratory support.

Weil’s Disease (Fulminating Leptospirosis) Complicating as Acute Respiratory Distress Syndrome

Leptospiroisis presents with a wide range of clinical symptoms, ranging from mild disease symptoms to life threatening complications. The clinical features and routine laboratory findings are not specific, and therefore a high index of suspicion must be maintained for the diagnosis. We documented a case of a patient, who presented with high grade fever, diarrhea, vomiting, had icterus on examination. Initial laboratory investigations revealed low platelet count, along with raised liver enzymes. IgM leptospirosis came positive and patients received broad spectrum antimicrobials and supportive fluid therapy. During admission, patient developed sudden onset breathlessness, which was diagnosed as acute respiratory distress syndrome after doing immediate arterial blood gases. The patient received noninvasive ventilation with positive airway pressure, from which the patient eventually recovered. Most of the cases of leptospirosis are uneventful with complete recovery. However, a minority of these cases may end with life threatening complications. A vaccine for human use is not available in most countries. Therefore, the prevention involves reducing exposure, either by avoiding situations that pose a risk of transmission or using protective clothing.

Cardiac Postoperative Use of High-Flow Nasal Cannula: A Retrospective Single-Center Study

We aimed to investigate the risk factors and reason for initiation of high-flow nasal cannula (HFNC), its benefit on re-intubation rate, mortality, and length of stay (LOS) in the postoperative cardiac surgery patient in the ICU. Methods: In a retrospective and descriptive study, 200 patients, who underwent cardiac surgery, were randomly included, and screened for initiation of postoperative respiratory support. Demographic patient data and pre-operative patient measurements were sampled. Data concerning the P/F ratio at arrival- and post-extubation, LOS at ICU and overall mortality were sampled. A comparison of those variables was performed between patients with and without need of respiratory support. Results: HFNC was initiated in approximately 22.45% in 2018, and 25% in 2020, of the patients. Comparing both years didn’t reveal a significant rise, but we saw a quicker use of HFNC in 2020. The all-case re-intubation rate and mortality was approximately 3%. The body mass index (BMI) was the only correlation with a higher chance of initiation of HFNC. Other data like age, pre-operative renal- or left ventricle function didn’t show a correlation. Conclusion: In case of respiratory insufficiency in the postoperative cardiac surgery setting, HFNC is a worthy first line treatment option which is initiated if conventional oxygen therapy doesn’t suffice. The mortality was low, and the mean LOS was 4.38 days. If respiratory support was started with HFNC mean LOS rose to 8.35 days. The BMI seems to have a correlation with the development of respiratory failure, which confirms the latest recommendation to start preventive HFNC in the post-extubation cardiac surgery setting and which could be implemented in the daily practice.

Effectiveness and safety of noninvasive positive-pressure ventilation for severe hypercapnic encephalopathy due to acute exacerbation of chronic obstructive pulmonary disease:a prospective case-control study

Background Although severe encephalopathy has been proposed as a possible contraindication to the use of noninvasive positive-pressure ventilation （NPPV）, increasing clinical reports showed it was effective in patients with impaired consciousness and even coma secondary to acute respiratory failure, especially hypercapnic acute respiratory failure （HARF）. To further evaluate the effectiveness and safety of NPPV for severe hypercapnic encephalopathy, a prospective case-control study was conducted at a university respiratory intensive care unit （RICU） in patients with acute exacerbation of chronic obstructive pulmonary disease （AECOPD） during the past 3 years. Methods Forty-three of 68 consecutive AECOPD patients requiring ventilatory support for HARF were divided into 2 groups, which were carefully matched for age, sex, COPD course, tobacco use and previous hospitalization history, according to the severity of encephalopathy, 22 patients with Glasgow coma scale （GCS） 〈10 served as group A and 21 with GCS 〉10 as group B. Results Compared with group B, group A had a higher level of baseline arterial partial CO2 pressure （（102±27） mmHg vs （74±17） mmHg, P〈0.01）, lower levels of GCS （7.5±1.9 vs 12.2±1.8, P〈0.01）, arterial pH value （7.18±0.06 vs 7.28±0.07, P〈0.01） and partial 02 pressure/fraction of inspired 02 ratio （168±39 vs 189±33, P〈0.05）. The NPPV success rate and hospital mortality were 73% （16/22） and 14% （3/22） respectively in group A, which were comparable to those in group B （68% （15/21） and 14% （3/21） respectively, all P〉0.05）, but group A needed an average of 7 cmH20 higher of maximal pressure support during NPPV, and 4, 4 and 7 days longer of NPPV time, RICU stay and hospital stay respectively than group B （P〈0.05 or P〈0.01）. NPPV therapy failed in 12 patients （6 in each group） because of excessive airway secretions （7 patients）, hemodynamic instability （2）, worsening of dyspnea and deterioration of gas exchange （2）, and gastric content aspiration （1）. Conclusions Selected patients with severe hypercapnic encephalopathy secondary to HARF can be treated as effectively and safely with NPPV as awake patients with HARF due to AECOPD; a trial of NPPV should be instituted to reduce the need of endotracheal intubation in patients with severe hypercapnic encephalopathy who are otherwise good candidates for NPPV due to AECOPD.

Effect of noninvasive, positive pressure ventilation on patients with severe, stable chronic obstructive pulmonary disease： a meta-analysis

Background This meta-analysis evaluated the effect of noninvasive, positive pressure ventilation on severe, stable chronic obstructive pulmonary disease （COPD）. Methods PUBMED, CNKI, Wanfang, EMBASE and the Cochrane trials databases were searched. Randomized controlled trials of patients with severe, stable COPD and receiving noninvasive positive pressure ventilation, compared with sham ventilation or no ventilation, were reviewed. The mortality, physiological and health related parameters were pooled to yield odds ratio （OR）, weighted mean differences or standardized mean differences （SMD）, with 95% confidence interval （CI）. Results Eight parallel and three crossover randomized controlled trials met the inclusion criteria. Pooled analysis for parallel, randomized controlled trials showed noninvasive positive pressure ventilation： （1） Did not affect the 12- or 24-month mortality （OR 0.82, 95% Ch 0.48 to 1.41）; （2） Improved the arterial carbon dioxide tension （SMD -0.88, 95% Ch -1.43 to -0.34）; （3） Did not improve forced expiratory volume in one second （SMD 0.20, 95% CI： -0.06 to 0.46）, maximal inspiratory pressure （SMD 0.01, 95% Ch -0.28 to 0.29） or 6-minute walk distance （SMD 0.17, 95% Ch -0.16 to 0.50）; （4） Subgroup analysis showed noninvasive positive pressure ventilation improved the arterial carbon dioxide tension in hypercapnic patients. Pooled analysis for crossover randomized controlled trials did not show improvement in arterial blood gas or forced expiratory volume in one second with noninvasive positive pressure ventilation. Conclusions Noninvasive positive pressure ventilation improves the arterial carbon dioxide tension but does not improve the mortality, pulmonary function, or exercise tolerance and should be cautiously used in severe stable chronic obstructive pulmonary disease.

Effect of noninvasive positive pressure ventilation on weaning success in patients receiving invasive mechanical ventilation： a meta-analysis

Background Noninvasive positive pressure ventilation （NIPPV） has been proposed to shorten the duration of mechanical ventilation in intubated patients, especially those who fail initial weaning from invasive mechanical ventilation （IMV）. However, there are also some discrepancies in terms of weaning success or failure, incidence of re-intubation, complications observed during study and patient outcomes. The primary objective of this update was to specifically investigate the role of NIPPV on facilitating weaning and avoiding re-intubation in patients intubated for different etiologies of acute respiratory failure, by comparing with conventional invasive weaning approach. Methods We searched randomized controlled trials （RCTs） comparing noninvasive weaning of early extubation and immediate application of NIPPV with invasive weaning in intubated patients from PubMed, Embase, Cochrane Central Register of Controlled Trials, Web of Knowledge and Springerlink databases. Records from conference proceedings and reference lists of relevant studies were also identified. Results A total of 11 RCTs with 623 patients were available for the present analysis. Compared with IMV, NIPPV significantly increased weaning success rates （odds ratio （OR）： 2.50, 95% confidence interval （C/）： 1.46-4.30, P=0.0009）, decreased mortality （OR： 0.39, 95% CI： 0.20-0.75, P=0.005）, and reduced the incidence of ventilator associated pneumonia （VAP） （OR： 0.17, 95% CI： 0.08-0.37, P 〈0.00001） and complications （OR： 0.22, 95% CI： 0.07-0.72, P=0.01）. However, effect of NIPPV on re-intubation did not reach statistical difference （OR： 0.61, 95% CI： 0.33-1.11, P=0.11）. Conclusions Early extubation and immediate application of NIPPV is superior to conventional invasive weaning approach in increasing weaning success rates, decreasing the risk of mortality and reducing the incidence of VAP and complications, in patients who need weaning from IMV. However, it should be applied with caution, as there is insufficient beneficial evidence to definitely recommend it in terms of avoidinQ re-intubation.

Bi-level Nasal Positive Airway Pressure(BiPAP)versus Nasal Continuous Positive Airway Pressure(CPAP)for Preterm Infants with Birth Weight Less Than 1500g and Respiratory Distress Syndrome Following INSURE Treatment:A Two-center Randomized Controlled Trial

The present study aimed to examine the effectiveness of bi-level positive airway pressure(BiPAP)versus continuous positive airway pressure(CPAP)in preterm infants with birth weight less than 1500 g and respiratory distress syndrome(RDS)following intubation-surfactant-extubation(INSURE)treatment.A two-center randomized control trial was performed.The primary outcome was the reintubation rate of infants within 72 h of age after INSURE.Secondary outcomes included bronchopulmonary dysplasia(BPD),necrotizing enterocolitis(NEC),retinopathy of prematurity(ROP)and incidences of adverse events.Lung function at one year of corrected age was also compared between the two groups.There were 140 cases in the CPAP group and 144 in the BiPAP group.After INSURE,the reintubation rates of infants within 72 h of age were 15%and 11.1%in the CPAP group and the BiPAP group,respectively(P>0.05).Neonates in the BiPAP group was on positive airway pressure(PAP)therapy three days less than in the CPAP group(12.6 d and 15.3 d,respectively,P<0.05),and on oxygen six days less than in the CPAP group(20.6 d and 26.9 d,respectively,P<0.05).Other outcomes such as BPD,NEC,ROP and feeding intolerance were not significantly different between the two groups(P>0.05).There was no difference in lung function at one year of age between the two groups(P>0.05).In conclusion,after INSURE,the reintubation rate of infants within 72 h of age was comparable between the BiPAP group and the CPAP group.BiPAP was superior to CPAP in terms of shorter durations(days)on PAP support and oxygen supplementation.There were no differences in the incidences of BPD and ROP,and lung function at one year of age between the two ventilation methods.

Efficacy and safety of noninvasive positive pressure ventilation in the treatment of acute respiratory failure after cardiac surgery

Background Although noninvasive positive pressure ventilation （NPPV） has been successfully used for various kinds of acute respiratory failure,the data are limited regarding its application in postoperative respiratory failure after cardiac surgery.Therefore,we conducted a prospective randomized control study in a university surgical intensive care unit to evaluate the efficacy and safety of NPPV in the treatment of acute respiratory failure after cardiac surgery,and explore the predicting factors of NPPV failure.Methods From September 2011 to November 2012 patients with acute respiratory failure after cardiac surgery who had indication for the use of NPPV were randomly divided into a NPPV treatment group （NPPV group） and the conventional treatment group （control group）.The between-group differences in the patients＇ baseline characteristics,re-intubation rate,tracheotomy rate,ventilator associated pneumonia （VAP） incidence,in-hospital mortality,mechanical ventilation time after enrollment （MV time）,intensive care unit （ICU） and postoperative hospital stays were compared.The factors that predict NPPV failure were analyzed.Results During the study period,a total of 139 patients who had acute respiratory failure after cardiac surgery were recorded,and 95 of them met the inclusion criteria,which included 59 males and 36 females with a mean age of （61.5±11.2） years.Forty-three patients underwent coronary artery bypass grafting （CABG）,23 underwent valve surgery,13 underwent CABG＋valve surgery,13 underwent major vascular surgery,and three underwent other surgeries.The NPPV group had 48 patients and the control group had 47 patients.In the NPPV group,the re-intubation rate was 18.8％,tracheotomy rate was 12.5％,VAP incidence was 0,and the in-hospital mortality was 18.8％,significantly lower than in the control group 80.9％,29.8％,17.0％ and 38.3％ respectively,P ＜0.05 or P ＜0.01.The MV time and ICU stay （expressed as the median （P25,P75）） were 18.0 （9.2,35.0） hours and 4.0 （2.0,5.0） days,which were significantly shorter than in the control group,96.0 （26.0,240.0） hours and 6.0 （4.0,9.0） days respectively,P ＜0.05 or P ＜0.01.The postoperative hospital stays of the two groups were similar.The univariate analysis showed that the NPPV success subgroup had more patients with acute lung injury （ALl） （17 vs.0,P=0.038）,fewer patients with pneumonia （2 vs.7,P ＜0.001） and lower acute physiology and chronic health evaluation Ⅱ （APACHE Ⅱ） scores （16.1±2.8 vs.21.8±3.2,P ＜0.001）.Multivariate analysis showed that pneumonia （P=-0.027） and a high APACHE Ⅱ score ＞20 （P=-0.002） were the independent risk factors of NPPV failure.Conclusions We conclude that NPPV can be applied in selected patients with acute respiratory failure after cardiac surgery to reduce the need of re-intubation and improve clinical outcome as compared with conventional treatment.Pneumonia and a high APACHE Ⅱ score ＞20 might be the independent risk factors of NPPV failure in this group of patients.

Early use of non-invasive positive pressure ventilation for acute exacerbations of chronic obstructive pulmonary disease:a multicentre randomized controlled trial

Background Respiratory muscle fatigue plays an important role in acute exacerbations of chronic obstructivepulmonary disease (AECOPD)·In previous clinical studies, non-invasive positive pressure ventilation (NPPV)was proved to be successful only for AECOPD patients with severe respiratory failure·We hypothesized that, theoutcomes of AECOPD would be improved if NPPVis early (within 24 to 48 hours of admission) administered inthose patients with respiratory muscle fatigue and mild respiratory insufficiency, especially in patients withoutfulfilling the conventional criteria of mechanical ventilatory support·Methods Aprospective multicentre randomized controlled trial was conducted in19 hospitals in China over16months·Three hundred and forty-two AECOPD patients with pH≥7·25 and PaCO2>45 mmHg were recruitedon general ward and randomly assigned to standard medical treatment (control group) or early administration ofadditional NPPV (NPPV group)·Results The characteristics of two groups on admission were similar·The number of AECOPD patientsrequiring intubations in NPPV group was much fewer than that of the control group (8/171 vs 26/71,P=0·002)·Subgroup analysis showed the needs for intubation in mildly (pH≥7·35) and severe (pH<7·30)acidotic patients in NPPVgroup were both decreased (9/80 vs2/71,P=0·047 and 8/30 vs3/43,P=0·048,respectively)·The mortality in hospital was reduced slightly by NPPV but with no significant difference (7/171vs 12/171,P=0·345)·Respiratory rate (RR),scale for accessory muscle use and arterial pHimproved rapidlyat the first 2 hours only in patients of NPPV group·After 24 hours, the differences of pH, PaO2, scale foraccessory muscle use and RR in NPPV group [(7·36±0·06) mmHg, (72±22) mmHg, (2·5±0·9) /min,(22±4) /min] were statistically significant compared with control group (7·37±0·05) mmHg, (85±34)mmHg, (2·3±1·1) /min, (21±4) /min,P<0·01 for all comparisons]·Conclusions The early use of NPPV on general ward improves arterial blood gas and respiratory pattern,decreases the rate of need for intubation in AECOPD patients·NPPV is indicative for alleviating respiratorymuscle fatigue and preventing respiratory failure from exacerbation·

Oxygenation strategies after extubation of critically ill and postoperative patients

In intensive care units(ICUs),the decision to extubate is a critical one because mortality is particularly high in case of reintubation.Around 15%of patients ready to be weaned offa ventilator experience extubation failure leading to reintubation.The use of high-flow nasal oxygen and non-invasive ventilation are two alternatives of standard oxygen supplementation that may help to prevent reintubation.High-flow nasal oxygen and non-invasive ventilation,may be used to prevent reintubation in patients with low(e.g.,patients without comorbidities and with short durations of mechanical ventilation)and high risk(e.g.,patients>65 years and those with underlying cardiac disease,chronic respiratory disorders,and/or hypercapnia at the time of extubation)of reintubation,respectively.However,non-invasive ventilation used as a rescue therapy to treat established post-extubation respiratory failure could increase mortality by delaying reintubation,and should therefore be used very carefully in this setting.The oxygenation strategy to be applied in postoperative patients is different from the patients who are extubated in the ICUs.Standard oxygen after a surgical procedure is adequate,even following major abdominal or cardio-thoracic surgery,but should probably be switched to high-flow nasal oxygen in patients with hypoxemic.Unlike in patients experiencing post-extubation respiratory failure in ICUs wherein non-invasive ventilation may have deleterious effects,it may actually improve the outcomes in postoperative patients with respiratory failure.This review discusses the different clinical situations with the aim of choosing the most effective oxygenation strategy to prevent post-extubation respiratory failure and to avoid reintubation.