Observation on the Effect of Non-Invasive Ventilator Combined with Conventional Therapy in the Treatment of Chronic Obstructive Pulmonary Disease Complicated with Respiratory Failure

Objective:To explore the clinical effect of a non-invasive ventilator combined with conventional therapy in the treatment of patients with chronic obstructive pulmonary disease(COPD)combined with respiratory failure.Methods:68 patients with COPD combined with respiratory failure treated in our hospital from September 2021 to October 2023 were selected as the research subjects.Using the random number table method,they were divided into a control group and an experimental group of 34 cases each.The control group received conventional symptomatic treatment,and the experimental group received non-invasive ventilator treatment based on the control group.The clinical effects,blood gas indicators(partial pressure of carbon dioxide(PaCO_(2)),partial pressure of oxygen(PaO_(2)),arterial oxygen saturation(SaO_(2))),lung function(forced expiratory volume in 1 second(FEV1),forced vital capacity(FVC),6 min walking distance),complications,and inflammatory factor levels(c-reactive protein(CRP),interleukin-6(IL-6),neutrophil-to-lymphocyte ratio(NLR))of the two groups of patients were observed.Results:(1)The clinical efficacy of the patients in the experimental group(33/97.06%)was more significant as compared with the control group(25/73.53%)(P<0.05);(2)After treatment,the clinical efficacy of the two groups of patients in terms of FEV1,FEV1/FVC,6-minute walking distance,PaO_(2)and SaO_(2)all increased in the experimental group as compared to that of the control group(P<0.05);(3)After treatment,the PaCO_(2),CRP,IL-6,and NLR of the two groups of patients decreased,and the decrease in the experimental group was higher than that of the control group(P<0.05);(4)The patients’complication rate in the experimental group(2/5.88%)was lower as compared to that of the control group(9/26.46%)(P<0.05).Conclusion:Non-invasive ventilators combined with conventional therapy achieved good clinical results in treating patients with COPD and respiratory failure.

Analysis of the Effect of Non-Invasive Positive Pressure Ventilation in Emergency Treatment of Severe Bronchial Asthma with Respiratory Failure

Objective:This study aims to evaluate the clinical efficacy of non-invasive positive pressure ventilation(NIPPV)in patients with severe bronchial asthma combined with respiratory failure.Methods:90 patients with severe bronchial asthma combined with respiratory failure between September 2022 and December 2023 were selected for the study and randomly divided into the experimental group(NIPPV-assisted treatment)and the control group.The differences between the two groups were compared in terms of total effective rate of treatment,days of clinical symptom disappearance,days of hospitalization,lung function indexes,incidence of adverse reactions,and quality of life.Results:Patients in the experimental group had a significantly higher total effective rate of treatment(97.78%)than the control group(75.56%).In terms of pulmonary function indexes,patients in the experimental group showed significant improvement after treatment,especially the increase in forced expiratory volume and forced vital capacity,while these improvements were not as obvious in the control group.In addition,the incidence of adverse reactions was significantly lower in the experimental group than in the control group,suggesting that the application of NIPPV is relatively safe.Quality of life assessment also showed that patients in the experimental group had significantly better quality of life than the control group after treatment.Conclusion:This study demonstrated the effectiveness of NIPPV as an adjunctive treatment for severe bronchial asthma combined with respiratory failure.NIPPV can improve lung function,reduce the incidence of adverse effects,increase the overall effectiveness of the treatment,and contribute to the improvement of patients'quality of life.Therefore,NIPPV should be regarded as an effective and safe treatment in clinical management,especially in patients with severe bronchial asthma combined with respiratory failure,where its application has potential clinical significance.

Invasive versus non-invasive ventilation in patients with COVID-19 pneumonia:A retrospective study

Objective:To compare the survival and length of stay of invasive ventilation(IV)with those of non-invasive ventilation(NIV)in patients with COVID-19 acute respiratory distress syndrome in a single hospital from May 2020 to March 2021.Methods:After obtaining approval from the Hospital Director,the data of COVID-19 patients including demographics,type of respiratory support(non-invasive ventilation or invasive ventilation),duration of ventilation,length of stay,discharge,and death were collected and analyzed.Results:Out of the 152 patients identified,134 patients were analyzed.The median intubation days were 10.0(Q1:3.5,Q3:13.5)in the IV group and 0.0(Q1:0.0,Q3:0.0)days in the NIV-only group.Out of the 101 patients who received NIV,43 patients were subsequently intubated due to failure of NIV.Of the 63 patients(47.01%)who died,22(66.66%)were from the IV group and 40(92.02%)were from the NIV-followed-by-intubation group,and 1(1.72%)were from the NIV-only group.Multivariate analysis showed that the presence of a respiratory comorbidity(OR=16.56,95%CI=1.56-175.48,P=0.02)was an independent predictor of survival.Conclusions:Respiratory co-morbidity is a significant adverse predictor of survival outcome.The decision on the type of respiratory support should be made on a patient-to-patient basis.

An Analysis of Nursing Factors Affecting Flatulence in Patients with Non-Invasive Ventilator Assisted Therapy

Objective:To analyze the factors of flatulence in patients treated with non-invasive ventilator and summarize practical and effective nursing measures.Methods:From July 2020 to June 2021,40 patients who complained of flatulence after using non-invasive ventilator were analyzed.Results:20 cases of abdominal distension were caused by the habit of breathing with their mouth open,10 cases of abdominal distention were caused by liking to eat soup,10 cases of abdominal distention were caused by long-term bed-in-bed activity reduced gastrointestinal peristalsis constipation.Conclusion:We should investigate the causes causing gastrointestinal flatulence with the use of non-invasive ventilators,intervene in advance,boost patient comfort,collaborate with therapy,and improve the therapeutic result.

Effects of pulmonary surfactant combined with noninvasive positive pressure ventilation in neonates with respiratory distress syndrome

BACKGROUND Neonatal respiratory distress syndrome(NRDS)is one of the most common diseases in neonatal intensive care units,with an incidence rate of about 7%among infants.Additionally,it is a leading cause of neonatal death in hospitals in China.The main mechanism of the disease is hypoxemia and hypercapnia caused by lack of surfactant AIM To explore the effect of pulmonary surfactant(PS)combined with noninvasive positive pressure ventilation on keratin-14(KRT-14)and endothelin-1(ET-1)levels in peripheral blood and the effectiveness in treating NRDS.METHODS Altogether 137 neonates with respiratory distress syndrome treated in our hospital from April 2019 to July 2021 were included.Of these,64 control cases were treated with noninvasive positive pressure ventilation and 73 observation cases were treated with PS combined with noninvasive positive pressure ventilation.The expression of KRT-14 and ET-1 in the two groups was compared.The deaths,complications,and PaO_(2),PaCO_(2),and PaO_(2)/FiO_(2)blood gas indexes in the two groups were compared.Receiver operating characteristic curve(ROC)analysis was used to determine the diagnostic value of KRT-14 and ET-1 in the treatment of NRDS.RESULTS The observation group had a significantly higher effectiveness rate than the control group.There was no significant difference between the two groups in terms of neonatal mortality and adverse reactions,such as bronchial dysplasia,cyanosis,and shortness of breath.After treatment,the levels of PaO_(2)and PaO_(2)/FiO_(2)in both groups were significantly higher than before treatment,while the level of PaCO_(2)was significantly lower.After treatment,the observation group had significantly higher levels of PaO_(2)and PaO_(2)/FiO_(2)than the control group,while PaCO_(2)was notably lower in the observation group.After treatment,the KRT-14 and ET-1 levels in both groups were significantly decreased compared with the pre-treatment levels.The observation group had a reduction of KRT-14 and ET-1 levels than the control group.ROC curve analysis showed that the area under the curve(AUC)of KRT-14 was 0.791,and the AUC of ET-1 was 0.816.CONCLUSION Combining PS with noninvasive positive pressure ventilation significantly improved the effectiveness of NRDS therapy.KRT-14 and ET-1 levels may have potential as therapeutic and diagnostic indicators.

Non-invasive ventilation improves hemorheology status in hypoxemic patients with acute myocardial infarction after PCI

Background Hypoxemia sometimes occurs in the emergency room in the patients with acute myocardial infarction （AMI） after percutaneous coronary intervention （PCI）, even in those with administration of conventional high-flow oxygen inhalation. The objective of the present study was to evaluate the effectiveness of non-invasive ventilation （NIV） in improving blood oxygen content and hemorheology in patients with AMI and hypoxemia. Methods This prospective study enrolled 50 consecutive eligible patients with AMI （aged 72.3 ± 9.5 years）, who had undergone PCI and been administered high-flow oxygen but still had hypoxemia. Blood was taken before NIV and at 0.5, 1, and 2 h after NIV. Blood gases, hemorheological variables including erythrocyte deformability, erythrocyte aggregation, erythrocyte osmotic fragility, membrane fluidity, and oxidative stress level were measured. Results Blood PaO2 increased to normal by 1 h after NIV. Assessed hemorheological variables had all improved and plasma malondialdehyde concentration decreased significantly after 2 h of NIV. Conclusions Our data suggest that NIV can help to improve blood oxygen content, hemorheological status, and minimize plasma lipid peroxidation injury in hypoxemic patients with AMI who have undergone PCI.

Clinical outcomes of moderate to severe COVID-19 patients receiving invasive vs. non-invasive ventilation

Objective:To evaluate the in-hospital outcome of moderate to severe COVID-19 patients admitted in High Dependency Unit(HDU)in relation to invasive vs.non-invasive mode of ventilation.Methods:In this study,the patients required either non-invasive[oxygen≤10 L/min or>10 L/min through mask or nasal prongs,rebreather masks and bilevel positive airway pressure(BiPAP)]or invasive ventilation.For analysis of 30-day in hospital mortality in relation to use of different modes of oxygen,Kaplan Meier and log rank analyses were used.In the end,independent predictors of survival were determined by Cox regression analysis.Results:Invasive ventilation was required by 15.1%patients while 84.9%patients needed non-invasive ventilation.Patients with evidence of thromboembolism,high inflammatory markers and hypoxemia mainly required invasive ventilation.The 30-day in hospital mortality was 72.7%for the invasive group and 12.9%for the non-invasive group(1.8%oxygen<10 L/min,0.9%oxygen>10 L/min,3.6%rebreather mask and 4.5%BiPAP).The median time from hospital admission to outcome was 7 days for the invasive group and 18 days for the non-invasive group(P<0.05).Age,presence of co-morbidities,number of days requiring oxygen,rebreather,BiPAP and invasive ventilation were independent predictors of outcome.Conclusions:Invasive mechanical ventilation is associated with adverse outcomes possibly due to ventilator associated lung injury.Thus,protective non-invasive ventilation remains the necessary and safe treatment for severely hypoxic COVID-19 patients.

Application of non-invasive ventilator in the treatment of acute heart failure merged with respiratory failure in ICU

Objective:To observe the application effect of non-invasive ventilator in the treatment of acute heart failure merged with respiratory failure in ICU.Methods:A total of 80 patients with acute heart failure merged with respiratory failure who were admitted in ICU from January, 2015 to January, 2016 were included in the study and randomized into the observation group and the control group with 40 cases in each group. The patients in the two groups were given routine treatments after admission. On this basis, the patients in the observation group were given non-invasive ventilator. The patients in the control group were given continuous low flow oxygen inhalation. PaO2, pH, PaCO2, SaO2, and PaO2/FiO2 before and after treatment between the two groups were compared. The serum NT-pro BNP and cTnI levels before treatment, 24 h and 48 h after treatment in the two groups were compared.Results:The comparison of PaO2, pH, PaCO2, SaO2, and PaO2/FiO2 before treatment between the two groups was not statistically significant. PaO2, pH, SaO2, and PaO2/FiO2 after treatment in the two groups were significantly elevated, while PaCO2 was significantly reduced when compared with before treatment. PaO2, pH, SaO2, and PaO2/FiO2 after treatment in the observation group were significantly higher than those in the control group, while PaCO2 was significantly lower than that in the control group. The comparison of NT-pro BNP and cTnI levels before treatment between the two groups was not statistically significant. NT-pro BNP and cTnI levels 12 h and 24 h after treatment in the two groups were significantly elevated when compared with before treatment. NT-pro BNP and cTnI levels 12 h and 24 h after treatment in the observation group were significantly lower than those in the control group.Conclusions:Non-invasive ventilator in the treatment of acute heart failure merged with respiratory failure can effectively improve the ventilation function, reduce NT-pro BNP and cTnI levels, and is of great significance in enhancing the rescued effect.

Effect of lung lavage via fiber bronchoscope combined with non-invasive positive pressure ventilation on the blood gas results and systemic state of patients with COPD complicated by severe pneumonia

Objective: To discuss the effect of lung lavage via fiber bronchoscope combined with non-invasive positive pressure ventilation on the blood gas results and systemic state of patients with COPD complicated by severe pneumonia. Methods: A total of 68 patients with COPD complicated by severe pneumonia who were treated in the hospital between November 2015 and April 2017 were collected, retrospectively analyzed and then divided into the group A (n=35) who received noninvasive positive pressure ventilation and the group B (n=33) who received lung lavage via fiber bronchoscope combined with non-invasive positive pressure ventilation. The differences in arterial blood gas and serum index levels were compared between the two groups before and after treatment. Results: Before treatment, there was no statistically significant difference in arterial blood gas index levels as well as serum contents of inflammatory mediators, stress hormones and myocardial enzyme spectrum indexes between the two groups. After treatment, arterial blood gas indexes PH and PaO2 levels of group B were higher than those of group A;serum inflammatory mediators HMGB1, PCT and hs-CRP contents were lower than those of group A;serum stress hormones Cor, AngⅠ and AngⅡcontents were lower than those of group A;serum myocardial enzyme spectrum indexesα-HBDH and cTn-Ⅰ contents were lower than those of group A. Conclusion: Lung lavage via fiber bronchoscope combined with non-invasive positive pressure ventilation can effectively optimize the arterial blood gas levels, reduce systemic inflammatory stress state and protect the myocardial function of patients with COPD complicated by severe pneumonia.

COVID-19 managed with early non-invasive ventilation and a bundle pharmacotherapy: A case report

BACKGROUND The coronavirus disease 2019(COVID-19)pandemic has become an immense public health burden,first in China and subsequently worldwide.Developing effective control measures for COVID-19,especially measures that can halt the worsening of severe cases to a critical status is of urgent importance.CASE SUMMARY A 52-year-old woman presented with a high fever(38.8°C),chills,dizziness,and weakness.Epidemiologically,she had not been to Wuhan where COVID-19 emerged and did not have a family history of a disease cluster.A blood test yielded a white blood cell count of 4.41×109/L(60.6±2.67%neutrophils and 30.4±1.34%lymphocytes).Chest imaging revealed bilateral ground-glass lung changes.Based on a positive nasopharyngeal swab nucleic acid test result and clinical characteristics,the patient was diagnosed with COVID-19.Following treatment with early non-invasive ventilation and a bundle pharmacotherapy,she recovered with a good outcome.CONCLUSION Early non-invasive ventilation with a bundle pharmacotherapy may be an effective treatment regimen for the broader population of patients with COVID-19.

Non-Invasive Positive Pressure Ventilation (NIPPV) in the Pregnant Patient: A Case Series

Rationale: Acute respiratory failure is an uncommon complication of pregnancy. However, it is the most frequent organ dysfunction associated with obstetric admissions to an intensive care unit. The obstetric population is a different group due to its physiology and the presence of the fetus that lacks evidence in the literature within the subject of ventilatory support. Noninvasive positive pressure ventilation (NIPPV) is often avoided due to the lack of knowledge on the safety and efficacy of this modality. Currently, there are no guidelines for the management of respiratory failure in pregnancy. Objectives: To provide evidence in support of the use of NIPPV as a safe and reasonable modality for pregnant patients with respiratory failure. Methods: We retrospectively reviewed medical records of 29 pregnant patients of the Obstetric Critical Care Unit of a tertiary hospital in Panamá City who received NIPPV from 2013 to 2015. Failure to response was defined as the lack of increase in the paO2/FiO2 ratio or clinical deterioration 6 hours after initiating NIPPV. Demographics, indication for NIPPV, duration of treatment, as well as maternal and fetal outcomes were collected. Measurements and Main Results: Mean age was 28.4 ± 6 years, mean body mass index 27.4 ± 3.3, and mean gestational age at admission was 305/7 ± 5 weeks. Twenty-four patients (82.8%) met the criteria for acute lung injury (ALI) and an additional two (6.9%) for acute respiratory distress syndrome (ARDS). The mean duration of ventilation was 50.6 ± 17.27 hours. Statistically significant differences were noted between the paO2/FiO2 ratios in failure and successful patients within 2 hours of NIPPV therapy (P = 0.007) and paO2/FiO2 ratio within 6 hours of NIPPV therapy (P = 0.03). Success was defined when the patient was administered NIPPV, resulting in an improvement (increase in pa/FiO2 ratio) of her ventilatory parameters. Three patients (10.3%) failed to respond to NIPPV and needed to be converted to invasive mechanical ventilation. Patients who required intubation had a longer duration of ICU stay (P = 0.006) and overall hospital stay (P = 0.03). None of patients presented aspiration during NIPPV therapy. Conclusion: The current series is the largest report of pregnant patients requiring ventilatory support who received NIPPV as first line of therapy. This report shows the usefulness of this ventilation modality, avoiding intubation with its risks, of a significant number of patients, especially ventilator-associated pneumonia.

Cardiopulmonary Stability on a Patient with Hip Fracture and Severe Pulmonary Hypertension, Anesthetized with Lumbar-Sacral Plexus Block and Non-Invasive Ventilation: Case Report

Background: Pulmonary hypertension is defined as a mean arterial pressure in the pulmonary artery exceeding 20 mm Hg at rest, measured by means of right heart catheterization. Patients with pulmonary hypertension undergoing surgical procedures such as hemiarthroplasty present a high risk of fatal complications. Nonetheless, there are no widely accepted protocols explaining their perioperative care in great detail. Case presentation: We present a case with an 89-years-old patient, with comorbidities such as GOLD 4D chronic obstructive pulmonary disease (COPD) and, as a consequence of this, severe pulmonary hypertension with signs of right ventricular dysfunction, thus requiring of pulmonary vasodilator, that has suffered a subcapital hip fracture requiring urgent surgery. Surgery is carried out successfully, under regional lumbar-sacral plexus block and sedation assisted by non-invasive ventilation. Conclusion: Multidisciplinary specialized treatment, preoperative optimization, as well as the careful selection of both the surgical and anesthetic techniques to be used, are among the strategies that improve the perioperative outcome in patients with pulmonary hypertension with right ventricle systolic dysfunction. Regional lumbar-sacral plexus block plus sedation is a technique that maintains hemodynamic stability;however, these patients require advance measures and postoperative monitoring under intensive care.

Non-Invasive Pressure Support Ventilation in Major Lung Resection for High Risk Patients: Does It Matter?

Background and purpose: Patients with severely impaired pulmonary function have an increased operative risk for major lung resection. The clinical benefits of pre- and perioperative, non-invasive pressure support ventilation (NIPSV) have up to now not been extensively evaluated. Patients with severely reduced pulmonary function were investigated in this prospective and randomised single centre clinical trial. Methods: Standard pulmonary evaluation was performed in all patients before major lung resection. To predict postoperative pulmonary function, a lung perfusion-ventilation scan was carried out. All patients enrolled in the study were instructed preoperatively on how to use a NIPSV respirator. Af-ter lung resection patients were randomised either for continuation of NIPSV or for standard treatment. Results: Of the 52 patients assessed, 21 patients met the inclusion criteria for the study protocol. Predicted mean postoperative FEV1 was 1.10 L (range 0.92 - 1.27 L). Lobectomy was performed in 14 patients, pneumonectomy in 6 patients and a segmentectomy in 1 patient. No inhospital deaths occurred. Pulmonary complications (reintubation, pneumonia) were more frequent in the NIPSV group than in the control group (3 patients versus 1 patient), without statistical significance (p = 0.31). Conclusions: We observed no mortality and a low morbidity in this high risk group. Postoperative continuation of NIPSV had no beneficial effect on the clinical outcome. Preoperative conditioning with NIPSV, however, seems to be a suitable tool for patients with severely impaired pulmonary function. This study may serve therefore as basis for further investigations for the potential clinical benefits of prophylactic NIPSV in major lung surgery.

Use of inflammatory markers as predictor for mechanical ventilation in COVID-19 patients with stagesⅢb-Ⅴchronic kidney disease?

BACKGROUND Studies have shown elevated C-reactive protein(CRP)to predict mechanical ventilation(MV)in patients with coronavirus disease 2019(COVID-19).Its utility is unknown in patients with chronic kidney disease(CKD),who have elevated baseline CRP levels due to chronic inflammation and reduced renal clearance.AIM To assess whether an association exists between elevated inflammatory markers and MV rate in patients with stagesⅢb-ⅤCKD and COVID-19.METHODS We conducted a retrospective cohort study on patients with COVID-19 and stagesⅢb-ⅤCKD.The primary outcome was the rate of invasive MV,the rate of noninvasive MV,and the rate of no MV.Statistical analyses used unpaired t-test for continuous variables and chi-square analysis for categorical variables.Cutoffs for variables were CRP:100 mg/L,ferritin:530 ng/mL,D-dimer:0.5 mg/L,and lactate dehydrogenase(LDH):590 U/L.RESULTS 290 were screened,and 118 met the inclusion criteria.CRP,D-dimer,and ferritin were significantly different among the three groups.On univariate analysis for invasive MV(IMV),CRP had an odds ratio(OR)-5.44;ferritin,OR-2.8;LDH,OR-7.7;D-dimer,OR-3.9,(P<0.05).The admission CRP level had an area under curve-receiver operator characteristic(AUROC):0.747 for the IMV group(sensitivity-80.8%,specificity-50%)and 0.663 for the non-IMV(NIMV)group(area under the curve,sensitivity-69.2%,specificity-53%).CONCLUSION Our results demonstrate a positive correlation between CRP,ferritin,and D-dimer levels and MV and NIMV rates in CKD patients.The AUROC demonstrates a good sensitivity for CRP levels in detecting the need for MV in patients with stagesⅢb-ⅤCKD.This may be because of the greater magnitude of increased inflammation due to COVID-19 itself compared with increased inflammation and reduced clearance due to CKD alone.

Mechanical ventilation and outcomes in COVID-19 patients admitted to intensive care unit in a low-resources setting: A retrospective study

Objective:To describe the strategies and outcomes of mechanical ventilation in a poorly equipped facility.Methods:This retrospective descriptive study included patients with COVID-19 who were admitted to the intensive care unit(ICU)and mechanically ventilated between September 1,2020,and May 31,2021.Data were collected from medical records and databases.Results:54 Patients aged(62.9±13.3)years were included.Among these cases,79.6%had at least one comorbidity.On admission,all patients had hypoxia.The median peripheral oxygen saturation in room air was 76%(61%,83%).Non-invasive ventilation(NIV)was performed in 75.9%of the patients,and invasive mechanical ventilation(IMV)in 68.5%.IMV was performed on patients due to severe coma(8.1%),failure of standard oxygen therapy(27.0%),and failure of NIV(64.9%).An arterial blood gas test was performed in 14.8%of the patients.NIV failed in 90.2%of cases and succeeded in 9.8%.IMV was successful in 5.4%of cases,vs.94.6%of mortality.The overall mortality rate of patients on ventilation in the ICU was 88.9%.The causes of death included severe respiratory distress syndrome(85.2%),multiple organ failure(14.8%),and pulmonary embolism(13.0%).Conclusions:The ventilation management of COVID-19 patients in the ICU with NIV and IMV in a scarce resource setting is associated with a high mortality rate.Shortcomings are identified in ventilation strategies,protocols,and monitoring.Required improvements were also proposed.

Hygrometry behavior during high-flow nasal oxygen therapy and non-invasive mechanical ventilation:A narrative review of bench to clinical studies

Recently,there has been growing interest in knowing the best hygrometry level during high-flow nasal oxygen and non-invasive ventilation(NIV)and its potential influence on the outcome.Various studies have shown that breathing cold and dry air results in excessive water loss by nasal mucosa,reduced mucociliary clearance,in-creased airway resistance,reduced epithelial cell function,increased inflammation,sloughing of tracheal epithe-lium,and submucosal inflammation.With the Coronavirus Disease 2019 pandemic,using high-flow nasal oxygen with a heated humidifier has become an emerging form of non-invasive support among clinicians.However,we cannot always assume stable humidification.Similarly,there are no clear guidelines for using humidification dur-ing NIV,although humidification of inspired gas during invasive ventilation is an accepted standard of care.NIV disturbs the normal physiological system that warms and humidifies inspired gases.If NIV is supplied through an intensive care unit ventilator that utilizes anhydrous gases from compressed wall air and oxygen,the risk of dry-ness increases.In addition,patients with acute respiratory failure tend to breathe through the mouth during NIV,which is a less efficient route than nasal breathing for adding heat and moisture to the inspired gas.Obstructive sleep apnea syndrome is one of the most important indications for chronic use of NIV at home.Available data suggest that up to 60%of patients with obstructive sleep apnea syndrome who use continuous positive airway pressure therapy experience nasal congestion and dryness of the mouth and nose.Therefore,humidifying the inspired gas in NIV may be essential for patient comfort and compliance with treatment.We aimed to review the available bench and clinical studies that addressed the utility of hygrometry in NIV and nasal high-flow oxygen and discuss the technical limitations of different humidification systems for both systems.

Effect of metronome rates on the quality of bag-mask ventilation during metronome-guided 30:2 cardiopulmonary resuscitation:A randomized simulation study

BACKGROUND: Metronome guidance is a feasible and effective feedback technique to improve the quality of cardiopulmonary resuscitation(CPR). The rate of the metronome should be set between 100 to 120 ticks/minute and the speed of ventilation may have crucial effect on the quality of ventilation. We compared three different metronome rates(100, 110, 120 ticks/minute) to investigate its effect on the quality of ventilation during metronome-guided 30:2 CPR.METHODS: This is a prospective, randomized, crossover observational study using a Respi Trainer r. To simulate 30 chest compressions, one investigator counted from 1 to 30 in cadence with the metronome rate(1 count for every 1 tick), and the participant performed 2 consecutive ventilations immediately following the counting of 30. Thirty physicians performed 5 sets of 2 consecutive(total 10) bag-mask ventilations for each metronome rate. Participants were instructed to squeeze the bag over 2 ticks(1.0 to 1.2 seconds depending on the rate of metronome) and defl ate the bag over 2 ticks. The sequence of three different metronome rates was randomized.RESULTS: Mean tidal volume significantly decreased as the metronome rate was increased from 110 ticks/minute to 120 ticks/minute(343±84 m L vs. 294±90 m L, P=0.004). Peak airway pressure significantly increased as metronome rate increased from 100 ticks/minute to 110 ticks/minute(18.7 vs. 21.6 mm Hg, P=0.006).CONCLUSION: In metronome-guided 30:2 CPR, a higher metronome rate may adversely affect the quality of bag-mask ventilations. In cases of cardiac arrest where adequate ventilation support is necessary, 100 ticks/minute may be better than 110 or 120 ticks/minute to deliver adequate tidal volume during audio tone guided 30:2 CPR.

Respiratory Volume Monitoring to Assess the Effect of Airway Maneuvers on Ventilation during Upper Endoscopy

Introduction: Propofol use during endoscopic procedures has become increasingly popular and assessing and maintaining airway patency is a significant challenge. Anesthesiologists often use airway maneuvers to maintain airway patency and ventilation during procedural sedation. A novel, non-invasive, Respiratory Volume Monitor (RVM) that provided continuous, real-time measurements of minute ventilation (MV), tidal volume (TV) and respiratory rate (RR) was used to monitor respiratory performance before, during, and after endoscopic procedures, quantify MV changes before and after airway maneuvers, and to quantify propofol-induced respiratory depression. Methods: RVM traces were obtained from 25 patients undergoing sedation for endoscopic procedures. Airway maneuvers were performed in 19/25 patients. All 25 patients received propofol as the primary sedative. Results: Forty-five airway maneuvers were performed. During these maneuvers, all respiratory parameters increased relative to pre-maneuver levels. On average, MV increased by 24% ± 5% (mean ± SEM), TV 14% ± 5% and RR: 17% ± 6%. The cohort average MVBASELINE was 9.5 ± 0.7 L/min (TV = 670 ± 60 ml, RR = 15 ± 0.7). Following propofol MV decreased transiently, reaching nadir five minutes after the last dose of propofol at 82% ± 10% of baseline (MV = 7.5 ± 1.0 L/min). The reduction in MV was driven by reduction in TV, not RR. Conclusions: Data demonstrated that RVM was able to track changes in ventilation and was able to quantify respiratory changes following airway maneuvers. All patients had a significant reduction in ventilatory volumes after propofol. Five minutes after the last dose of propofol, MV and TV were significantly reduced while RR was not, suggesting that monitoring respiratory rate alone was not a sufficient indicator of respiratory status.

Need for oxygen therapy and ventilatory support in premature infants in a hospital in Southern Brazil

BACKGROUND Prematurity in newborns is a condition that is associated with worse hospital outcomes when compared to birth to term.A preterm infant(PI)is classified when gestational age(GA)<37 wk.AIM To analyze prognostic indicators related to the use of oxygen therapy,noninvasive ventilation(continuous positive airway pressure)and mechanical ventilation(MV)in PI.METHODS This is a retrospective cohort.The sample was composed of PIs from a private hospital in southern Brazil.We included neonates with GA<37 wk of gestation in the period of January 1,2018 to December 31,2018.For data collection,electronic records were used in the Tasy Philips^(TM)system,identifying the variables:maternal age,type of birth,prenatal information,GA,Apgar score,birth weight,neonatal morbidities,vital signs in the 1st hour at birth,need for oxygen therapy,continuous positive airway pressure and MV,hospitalization in the neonatal intensive care unit,length of stay and discharge or death.RESULTS In total,90 PI records were analyzed.The median(p25-p75)of GA was 34.0(31.9-35.4)wk,and there were 45(50%)males.The most common morbidity among PIs was the acute respiratory discomfort syndrome,requiring hospitalization in the neonatal intensive care unit in 76(84.4%)cases.The utilization rate of oxygen therapy,continuous positive airway pressure and MV was 12(13.3%),37(41.1%)and 13(14.4%),respectively.The median(p25-p75)length of stay was 12.0(5.0-22.2)d,with 10(11.1%)deaths.A statistical association was observed with the use of MV and GA<28 wk,lower maternal age,low birth weight,Apgar<8 and neonatal deaths.CONCLUSION The identification of factors related to the need for MV in prematurity may help in the indication of a qualified team and technologies to promptly meet the unforeseen events that may occur after birth.

Clinical Study of P_(ET)CO_2 in One-lung Ventilation

Fourty-eight patients (ASA physical status Ⅰ - Ⅱ) undergoing selected thoracotomy and pulmonectomy were studied. They were divided into two groups according to different respiratory modes, two-lung ventilation (TLV) and onelung ventilation (OLV) or TLV and OLV with a Bain cyclic system for CPAP on the side of operated lung. PETCO2 and PaCO2 were measured after 30 min TLV,30 min and 60 min OLV, and repeated TLV (R-TLV) 30 min after pulmonectomy, to evaluate the difference between PETCO2 and PaCO2 in OLV and to observethe effect of abating hypoxemia and discharge of CO2 in OLV with Bain system.Our results showed that the PaCO2 and PETCO2 in different test groups were normal though the measured values in OLV were slightly higher than that in TLV (P<0. 05) , and then they were recovered after R-TLV (P>0. 05). There was nosignificant difference between group 1. and 2. in OLV (P>0. 05). There was aclose correlation between PETCO2 and PaCO2 (P<0. 05). The differences of the calculated P(a-ET)CO2 and radio of PETCO2/PaCO2 in different ventilation modes were not significant. Hypoxemia in OLV was corrected by Bain system, but the discharge of CO2 was not affected. The results showed that measurement of PET CO2 as a non-invasive procedure can be commonly used to monitor OLV.