High-Flow Oxygen Therapy in the Perioperative Setting and Procedural Sedation: A Review of Current Evidence

High-flow oxygen therapy (HFOT) is a respiratory support system, through which high flows of humidified and heated gas are delivered to hypoxemic patients. Several mechanisms explain how HFOT improves arterial blood gases and enhances patients' comfort. Some mechanisms are well understood, but others are still unclear and under investigation. HFOT is an interesting oxygen-delivery modality in perioperative medicine that has many clinical applications in the intensive care unit (ICU) and the operating room (OR). The purpose of this article was to review the literature for a comprehensive understanding of HFOT in the perioperative period, as well as its uses in procedural sedation. This review will focus on the HFOT definition, its physiological benefits, and their mechanisms, its clinical uses in anesthesia, and when it is contraindicated.

Psychological Factors Influencing Adherence to NIV in Neuromuscular Patients Dependent on Non Invasive Mechanical Ventilation: Preliminary Results

BACKGROUND

Non-invasive ventilation (NIV) is associated with improvement of both morbility and mortality in patients affected by neuromuscular diseases with chronic respiratory failure. Several studies have also shown that long-term NIV positively impacts the patient's quality of life and perception of disease status. Its effectiveness is likely related to the adherence to NIV. Several factors, patient- and not patient-related, may compromise adherence to NIV, such as physical, behavioral, familiar, and social issues. Few data are currently available on the role of psychological factors in influencing NIV adherence.

MATERIALS AND METHODS

In this pilot study, we evaluated the adherence to NIV in a group of 15 adult patients with neuromuscular diseases (Duchenne muscular dystrophy, myotonic dystrophy, and amyotrophic lateral sclerosis) in relation to their grade of depression assessed by the Beck Depression Inventory (BDI) questionnaire. Other data were collected, such as clinical features (age and sex), use of anxiolytic drugs, the presence of a family or professional caregiver, the quality of patient-physician relationship, the beginning of psychological support after BDI screening, and the family acceptance of NIV. NIV adherence was definied as the use of NIV for at least 4 h per night on 70% of nights in a month.

RESULTS

The overall rate of NIV adherence was 60%. Based on the BDI questionnaire, patients who were non-adherent to NIV had a higher rate of depression, mainly observed in the oldest patients. The acceptance of NIV by the family and positive physician-patient interaction seem to favor NIV adherence.

CONCLUSION

Depression can interfere with NIV adherence in patients with neuromuscolar diseases.

The Use of High-Flow Nasal Cannula and Non-Invasive Mechanical Ventilation in the Management of COVID-19 Patients: A Prospective Study

High-flow nasal cannula (HFNC) and ventilator-delivered non-invasive mechanical ventilation (NIV) were used to treat acute respiratory distress syndrome (ARDS) due to COVID-19 pneumonia, especially in low- and middle-income countries (LMICs), due to lack of ventilators and manpower resources despite the paucity of data regarding their efficacy. This prospective study aimed to analyse the efficacy of HFNC versus NIV in the management of COVID-19 ARDS. A total of 88 RT-PCR-confirmed COVID-19 patients with moderate ARDS were recruited. Linear regression and generalized estimating equations (GEEs) were used for trends in vital parameters over time. A total of 37 patients were on HFNC, and 51 were on NIV. Patients in the HFNC group stayed slightly but not significantly longer in the ICU as compared to their NIV counterparts (HFNC vs. NIV: 8.00 (4.0-12.0) days vs. 7.00 (2.0-12.0) days; p = 0.055). Intubation rates, complications, and mortality were similar in both groups. The switch to HFNC from NIV was 5.8%, while 37.8% required a switch to NIV from HFNC. The resolution of respiratory alkalosis was better with NIV. We conclude that in patients with COVID-19 pneumonia with moderate ARDS, the duration of treatment in the ICU, intubation rate, and mortality did not differ significantly with the use of HFNC or NIV for respiratory support.

Effects of Different Anticoagulation Doses on Moderate-to-Severe COVID-19 Pneumonia With Hypoxemia

Background COVID-19 is a prothrombotic disease that can cause thromboembolism and microthrombi, which could lead to multiorgan failure and death. Since COVID-19 is a relatively new disease, there are guidelines for anticoagulation dosing for COVID-19 patients without consensus on the dosing. We studied the effects of different doses of anticoagulation in hospitalized patients with COVID-19 pneumonia and hypoxemia on any differences in need for high-flow oxygen, mechanical ventilation, and mortality. We also analyzed the patient population who benefited most from anticoagulation. Methodology We performed a retrospective chart review of all patients who were admitted with the diagnosis of COVID-19 infection with positive polymerase chain reaction, pneumonia (confirmed either by chest X-ray or CT chest), and hypoxemia (oxygen saturation of <94%, while on room air). These patients were studied for outcomes (the need for high-flow oxygen, the requirement for mechanical ventilation, and overall mortality) for different doses of anticoagulation (prophylactic, escalated, and therapeutic). Results The sample consists of 132 subjects, predominantly males (116, 87%), with a mean age of 59 years and a standard deviation of 15. About one-third of the participants had diabetes, and more than 50% had hypertension. Additionally, 27 (20.3%) had a history of heart disease, and 70 (53%) of the subjects were admitted to the intensive care unit (ICU) at some point during the study. Among those admitted to the ICU, about 11 (8%) subjects required mechanical ventilation and 16 (12%) passed away during the study. Those who died had higher use of high-flow oxygen, noninvasive mechanical ventilation, and invasive mechanical ventilation and had a longer stay on mechanical ventilation. There was no significant difference in mortality or need for mechanical ventilation for any strategy of anticoagulation. Conclusions Different doses of anticoagulation did not show any statistically significant relationship between the need for mechanical ventilation and mortality. More patients on high-flow oxygen had received escalated doses of anticoagulation as compared to those who were not on high-flow oxygen. Anticoagulation levels did not have any statistically significant effect on overall survival of patients.

The role of prone positioning in patients with SARS-CoV-2-related respiratory failure in non-intensive care unit

BACKGROUND

Prone positioning (PP) is an established and commonly used lung recruitment method for intubated patients with severe acute respiratory distress syndrome, with potential benefits in clinical outcome. The role of PP outside the intensive care unit (ICU) setting is debated.

OBJECTIVES

We aimed at assessing the role of PP in death and ICU admission in non-intubated patients with acute respiratory failure related to COronaVIrus Disease-19 (COVID-19) pneumonia.

DESIGN

This is a retrospective analysis of a collaborative multicenter database obtained by merging local non-interventional cohorts.

METHODS

Consecutive adult patients with COVID-19-related respiratory failure were included in a collaborative cohort and classified based on the severity of respiratory failure according to the partial arterial oxygen pressure to fraction of inspired oxygen ratio (PaO₂/FiO₂) and on clinical severity by the quick Sequential Organ Failure Assessment (qSOFA) score. The primary study outcome was the composite of in-hospital death or ICU admission within 30 days from hospitalization.

RESULTS

PP was used in 114 of 536 study patients (21.8%), more commonly in patients with lower PaO₂/FiO₂ or receiving non-invasive ventilation and less commonly in patients with known comorbidities. A primary study outcome event occurred in 163 patients (30.4%) and in-hospital death in 129 (24.1%). PP was not associated with death or ICU admission (HR 1.17, 95% CI 0.78-1.74) and not with death (HR 1.01, 95% CI 0.61-1.67) at multivariable analysis; PP was an independent predictor of ICU admission (HR 2.64, 95% CI 1.53-4.40). The lack of association between PP and death or ICU admission was confirmed at propensity score-matching analysis.

CONCLUSION

PP is used in a non-negligible proportion of non-intubated patients with COVID-19-related severe respiratory failure and is not associated with death but with ICU admission. The role of PP in this setting merits further evaluation in randomized studies.

COVID-19 Pneumonia Complicated by Pneumomediastinum: A Case Report

Coronavirus disease 2019 (COVID-19) is a pandemic that spread rapidly around the world, causing an enormous overload on the health systems of the different affected countries. Among the many different manifestations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, an uncommon complication is the development of pneumomediastinum. In the clinical case presented, the patient was diagnosed with COVID-19 pneumonia and due to severe refractory hypoxemia, she was submitted to therapy with non-invasive ventilation (NIV). After initial stabilization and improvement, there was unexpected clinical deterioration and pneumomediastinum was diagnosed. The purpose of this report is to highlight the importance of considering pneumomediastinum as a complication of COVID-19 pneumonia in cases subjected to non-invasive ventilation.

Mallampati Score Is an Independent Predictor of Active Oxygen Therapy in Patients with COVID-19

Mallampati score has been identified and accepted worldwide as an independent predictor of difficult intubation and obstructive sleep apnea. We aimed to determine whether Mallampati score assessed on the first patient medical assessment allowed us to stratify the risk of worsening of conditions in patients hospitalized due to COVID-19. A total of 493 consecutive patients admitted between 13 November 2021 and 2 January 2022 to the temporary hospital in Pyrzowice were included in the analysis. The clinical data, chest CT scan, and major, clinically relevant laboratory parameters were assessed by patient-treating physicians, whereas the Mallampati score was assessed on admission by investigators blinded to further treatment. The primary endpoints were necessity of active oxygen therapy (AOT) during hospitalization and 60-day all-cause mortality. Of 493 patients included in the analysis, 69 (14.0%) were in Mallampati I, 57 (11.6%) were in Mallampati II, 78 (15.8%) were in Mallampati III, and 288 (58.9%) were in Mallampati IV. There were no differences in the baseline characteristics between the groups, except the prevalence of chronic kidney disease (p = 0.046). Patients with Mallampati IV were at the highest risk of AOT during the hospitalization (33.0%) and the highest risk of death due to any cause at 60 days (35.0%), which significantly differed from other scores (p = 0.005 and p = 0.03, respectively). Mallampati IV was identified as an independent predictor of need for AOT (OR 3.089, 95% confidence interval 1.65−5.77, p < 0.001) but not of all-cause mortality at 60 days. In conclusion, Mallampati IV was identified as an independent predictor of AOT during hospitalization. Mallampati score can serve as a prehospital tool allowing to identify patients at higher need for AOT.

Pneumomediastinum and Pneumothorax Following Non-invasive Respiratory Support in Patients With Severe COVID-19 Disease

The coronavirus disease-2019 (COVID-19) pandemic led to an increased number of patients with pneumothorax and pneumomediastinum owing to complications attributed to viral pneumonia regardless of the use of mechanical invasive ventilation and the elapsed time of infection. The pathophysiology remains unknown. However, the Macklin effect is shown as the most plausible mechanism along with possible barotrauma secondary to a high-flow nasal cannula and noninvasive mechanical ventilation. We present two cases of patients who developed pneumomediastinum and tension pneumothorax. One of the patients was studied during infection and the other after recovery. Both received appropriate and timely treatments with successful outcomes. It is important to be aware of these potentially fatal complications as early management can reduce the associated morbidity and mortality.

Heart Failure Patients and Implications of Obesity: A Single-Center Retrospective Study

Background and objective The prevalence of heart failure (HF) is on the rise; currently, it affects around five million people in the United States (US) and the prevalence is expected to rise from 2.42% in 2012 to 2.97% in 2030. HF is a leading cause of hospitalizations and readmissions, accounting for a major economic burden to the US healthcare system. Obesity is a widely accepted risk factor of HF; however, data regarding its independent association with HF mortality and morbidity is heterogeneous. Globally, more than two-thirds of deaths attributable to high body mass index (BMI) are due to cardiovascular diseases (CVD). This study aimed to investigate the potential role of obesity (BMI >30 Kg/m2) in HF patients in terms of 30-day readmissions, in-hospital mortality, and the use of noninvasive positive pressure ventilation (NIPPV). Methods In this single-center, retrospective study, all adult (age: >18 years) patients who were hospitalized with a primary diagnosis of HF at the Abington Jefferson Hospital from January 2015 to January 2018 were included. Demographic characteristics were collected manually from electronic medical records. Outcomes were 30-day readmission due to HF, all-cause in-hospital mortality, and requirement for NIPPV. Multivariable logistic regression analysis was conducted to investigate the association of obesity with HF outcomes. Results A total of 1,000 patients were initially studied, of these 800 patients were included in the final analysis based on the inclusion criteria. Obese patients showed higher odds for 30-day readmissions and the use of NIPPV compared to non-obese patients. There was no significant difference in in-hospital mortality in obese vs. non-obese patients. Conclusions Based on our findings, BMI >30 Kg/m2 is an independent risk factor for HF readmissions. Additionally, our results highlight the importance of guidelines-directed medical therapy (GDMT) for HF exacerbation, a low threshold for use of NIPPV in obese patients, promotion of lifestyle modifications including weight loss, and early follow-up after discharge to prevent HF readmissions in the obese population.

COPD, Pulmonary Fibrosis and ILAs in Aging Smokers: The Paradox of Striking Different Responses to the Major Risk Factors

Aging and smoking are associated with the progressive development of three main pulmonary diseases: chronic obstructive pulmonary disease (COPD), interstitial lung abnormalities (ILAs), and idiopathic pulmonary fibrosis (IPF). All three manifest mainly after the age of 60 years, but with different natural histories and prevalence: COPD prevalence increases with age to >40%, ILA prevalence is 8%, and IPF, a rare disease, is 0.0005–0.002%. While COPD and ILAs may be associated with gradual progression and mortality, the natural history of IPF remains obscure, with a worse prognosis and life expectancy of 2–5 years from diagnosis. Acute exacerbations are significant events in both COPD and IPF, with a much worse prognosis in IPF. This perspective discusses the paradox of the striking pathological and pathophysiologic responses on the background of the same main risk factors, aging and smoking, suggesting two distinct pathophysiologic processes for COPD and ILAs on one side and IPF on the other side. Pathologically, COPD is characterized by small airways fibrosis and remodeling, with the destruction of the lung parenchyma. By contrast, IPF almost exclusively affects the lung parenchyma and interstitium. ILAs are a heterogenous group of diseases, a minority of which present with the alveolar and interstitial abnormalities of interstitial lung disease.

Preemptive high-flow nasal cannula treatment in severe bronchiolitis: Results from a high-volume, resource-limited pediatric emergency department

BACKGROUND

The aims of this study were to evaluate the outcomes of patients with severe bronchiolitis who received preemptive high-flow nasal cannula (HFNC) treatment according to the authors' protocol, and to identify potential baseline characteristics that might predict patients who will not benefit from HFNC.

METHODS

This was a retrospective chart review of patients with severe bronchiolitis, who received preemptive HFNC treatment according to the authors' protocol and who were admitted to the pediatric emergency department between January 1, 2015, and December 31, 2016.

RESULTS

Eighty-four patients in total were enrolled over the 2 year period. Twenty-three patients (27.3%) failed HFNC. Of these, four responded to non-invasive mechanical ventilation and 19 required subsequent invasive ventilation. According to logistic regression analysis, existence of a chronic condition, significant tachycardia, existence of dehydration, and a venous pH <7.30 at admission were found to be predictors of HFNC failure. There were no cases of pneumothorax or any other reported adverse effects related to HFNC therapy.

CONCLUSIONS

Preemptive HFNC treatment, complying with a preestablished protocol, might be a safe way to support patients with severe bronchiolitis in high-volume, resource-limited pediatric emergency departments. The existence of a chronic condition, significant tachycardia, dehydration, and a venous pH <7.30 at admission could be risk factors for preemptive HFNC treatment failure in severe bronchiolitis.

Treatment of acute respiratory failure in the course of COVID-19. Practical hints from the expert panel of the Assembly of Intensive Care and Rehabilitation of the Polish Respiratory Society

In 2019, a pandemic began due to infection with a novel coronavirus, SARS-CoV-2. In many cases, this coronavirus leads to the development of the COVID-19 disease. Lung damage in the course of this disease often leads to acute hypoxic respiratory failure and may eventually lead to acute respiratory distress syndrome (ARDS). Respiratory failure as a result of COVID-19 can develop very quickly and a small percent of those infected will die because of it. There is currently no treatment for COVID-19, therefore the key therapeutic intervention centers around the symptomatic treatment of respiratory failure. The main therapeutic goal is to main-tain gas exchange, mainly oxygenation, at an appropriate level and prevent the intensification of changes in the lung parenchyma. Depending on the severity of hypoxemia different techniques can be used to improve oxygenation. Medical staff dealing with COVID-19 patients should be familiar with both, methods used to treat respiratory failure and the epidemiological risks arising from their use. In some patients, conventional (passive) oxygen therapy alone is sufficient. In patients with worsening respiratory failure high flow nasal oxygen therapy (HFNOT) may be effective. The continuous positive airway pressure (CPAP) and non-invasive ventilation (NIV) methods can be used to a limited extent. With further disease progression, invasive ventilation must be used and in special situations, extracorporeal membrane oxygenation (ECMO) can also be administered. The authors of this article set themselves the goal of presenting the most current knowledge about the epidemiology and patho-physiology of respiratory failure in COVID-19, as well as the methods of its treatment. Given the dynamics of the developing pandemic, this is not an easy task as new scientific data is presented almost every day. However, we believe the knowledge contained in this study will help doctors care for patients with COVID-19. The main target audience of this study is not so much pneumonologists or intensivists who have extensive experience in the application of the techniques discussed here, but rather doctors of other specializations who must master new skills in order to help patients during the time of a pandemic.

Covid-19: A systemic disease treated with a wide-ranging approach: A case report

At the end of December 2019, the Health Commission of the city of Wuhan, China, alerted the World Health Organization (WHO) to a pneumonia cluster in the city. The cause was identified as being a new virus, later named SARS-CoV-2. We can distinguish three clinical phases of the disease with a distinct pathogenesis, manifestations and prognosis. Here, we describe the case of a 45-year-old male, successfully treated for Coronavirus disease (COVID-19). The patient was feeling sick in early April 2020; he had a fever and pharyngodynia. When he came to our COVID hospital, his breathing was normal. The nasopharyngeal swab specimen turned out positive. High-resolution computed tomography (HRCT) showed mild interstitial pneumonia. The patient was admitted to our department and treated with hydroxychloroquine, ritonavir, darunavir, azithromycin and enoxaparin. On day seven of the disease, the patient's respiratory condition got worse as he was developing acute respiratory distress syndrome (ARDS). He was given tocilizumab and corticosteroids and was immediately treated with non-invasive mechanical ventilation (NIMV). His condition improved, and in the ensuing days, the treatment gradually switched to a high-flow nasal cannula (HFNC); after 18 days, the patient's clinical condition was good.The successful results we have been able to obtain are closely associated with avoidance of invasive ventilation that may lead to intensive care unit (ICU)-related superinfections. In our opinion, it is fundamental to understand that COVID-19 is a systemic disease that is a consequence of an overwhelming inflammatory response, which can cause severe medical conditions, even in young patients.

Refractory Acute Respiratory Distress Syndrome Secondary to COVID-19 Successfully Extubated to Average Volume-assured Pressure Support Non-invasive Ventilator

Coronavirus disease 2019 (COVID-19) is a respiratory illness caused by the highly infectious novel SARS-CoV-2 coronavirus spread by droplet transmission. Consequently, the use of respiratory devices that may potentially promote aerosolization like non-invasive positive pressure ventilation (NIPPV) for diseases such as obstructive sleep apnea (OSA), advanced chronic obstructive lung disease, pulmonary hypertension (PH), and neuromuscular respiratory disease has been called into question. We present a case of a patient with history of OSA and PH convalescing from refractory acute respiratory distress syndrome (ARDS) secondary to COVID-19 who was successfully extubated to average volume-assured pressure support (AVAPS).

A 74-year-old male with medical history notable for OSA on NIPPV, PH, and hypertension presented with respiratory failure secondary to COVID-19 confirmed on polymerase chain reaction (PCR) test. His respiratory status worsened leading to ARDS requiring intubation. He was initially extubated to high flow nasal cannula (HFNC) due to hospital policy to avoid NIPPV due to concerns of viral dissemination. He did not tolerate HFNC and required re-intubation for prolonged period. He was then medically optimized for a second attempt and extubated two days later to AVAPS with an anti-viral filter and negative pressure room with a goal of optimizing his critical illness myopathy and pre-existing OSA and PH. He tolerated extubation well, and over the next five days was weaned from alternating AVAPS/HFNC to eventually requiring two liters nasal cannula in the day and AVAPS mode at night.

This case highlights a potential therapeutic option for patients with severe respiratory failure secondary to COVID-19. This patient’s pre-existing comorbidities of OSA and PH markedly increased his risk for extubation failure on HFNC. The use of AVAPS after his second extubation attempt helped ensure ventilation and oxygenation non-invasively. COVID-19 can lead to prolonged dependence on mechanical ventilation. This pandemic has the potential to create medical resource scarcities, especially in rural areas where ventilators and trained personnel are already in short supply. By using AVAPS mode, this patient was able to rehabilitate his myopathy and participate in intermittent weaning of HFNC to ultimately simple nasal cannula.

AVAPS is useful tool to facilitate extubation, as it allows non-invasive support of respiratory dynamics, particularly in those with co-morbidities such as OSA and PH. Further, larger scale studies are needed to determine its exact role during the COVID-19 pandemic.

Chronic Vaping Related Tracheomalacia (TM): A Case of Vaping Induced Altered Innate Immunity that Culminated in Severe TM

Tracheomalacia (TM) is a weakness of the trachea either due to impaired cartilage integrity or atrophy of muscular elastic fibers. We present the first-ever case of chronic vaping induced altered immunological defenses that led to frequent pulmonary infections, ultimately culminating in severe TM which we successfully treated with positive airway pressure (PAP) therapy. A 53-year-old male presented with hypoxia and pneumonia refractory to outpatient antibiotics and steroids. He underwent bronchoscopy which showed severe TM, prompting transfer to our institution. He started vaping seven years ago and noted frequent bronchitis requiring antibiotics and steroids along with 10 life-time surgeries. He underwent repeat bronchoscopy noting TM, worst 3 cm above the carina and extending 4 cm proximally. The lesion was deemed not suitable for stenting, so PAP therapy was initiated. Bronchoalveolar lavage (BAL) confirmed 40% alveolar macrophages positive for lipid in Oil-O-Red stain consistent with EVALI. He tolerated PAP therapy with significant improvement in his ground glass opacities (GGO) and TM on subsequent imaging. TM is generally defined as >50% narrowing in the sagittal diameter. It is often further characterized into primary (congenital) or secondary (acquired) causes. Notable secondary causes include postintubation, chronic infection/bronchitis, chronic inflammation, and frequent steroid exposure -- all present in this case. Furthermore, there is existing literature that chronic inflammation due to irritants like cigarette smoke may be an important contributor to the development of TM. However, such data are lacking for EVALI. Our patient started experiencing repeated bronchitis episodes after he started vaping, leading to chronic inflammation and frequent antibiotics/steroids. Given his additional risk factor of multiple surgeries, this case not only presents a perfect storm for TM, but also a novel manifestation of EVALI. This case, to our knowledge, is the first-ever manifestation of EVALI presenting with TM. Management with PAP therapy helped avoid major surgery.

Dexmedetomidine Improves Cardiovascular and Ventilatory Outcomes in Critically Ill Patients: Basic and Clinical Approaches

Dexmedetomidine (DEX) is a highly selective α2-adrenergic agonist with sedative and analgesic properties, with minimal respiratory effects. It is used as a sedative in the intensive care unit and the operating room. The opioid-sparing effect and the absence of respiratory effects make dexmedetomidine an attractive adjuvant drug for anesthesia in obese patients who are at an increased risk for postoperative respiratory complications. The pharmacodynamic effects on the cardiovascular system are known; however the mechanisms that induce cardioprotection are still under study. Regarding the pharmacokinetics properties, this drug is extensively metabolized in the liver by the uridine diphosphate glucuronosyltransferases. It has a relatively high hepatic extraction ratio, and therefore, its metabolism is dependent on liver blood flow. This review shows, from a basic clinical approach, the evidence supporting the use of dexmedetomidine in different settings, from its use in animal models of ischemia-reperfusion, and cardioprotective signaling pathways. In addition, pharmacokinetics and pharmacodynamics studies in obese subjects and the management of patients subjected to mechanical ventilation are described. Moreover, the clinical efficacy of delirium incidence in patients with indication of non-invasive ventilation is shown. Finally, the available evidence from DEX is described by a group of Chilean pharmacologists and clinicians who have worked for more than 10 years on DEX.

The effects of non-invasive mechanic ventilator modes on intraocular pressure in COPD patients with hypercapnic respiratory failure

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is not fully reversible disease that is characterized by progressive restricting airflow. Non-invasive mechanical ventilation (NIMV) treatment can be used in COPD patients who had type 2 respiratory failure. This study aimed to determine the effect of BPAP S/T and AVAPS modes on intraocular pressure (IOP), central corneal thickness (CCT) in 40 type 2 respiratory failure patients with COPD.

METHODS

Forty patients with type 2 respiratory failure who were hospitalized between June and December 2018 with the diagnosis of COPD exacerbations were included to the study. Patients followed up without NIMV for 12 hours after the end of exacerbations treatments end. After IOP, visual acuity and CCT were measured in all patients at the same time (11.00 am), same NIMV treatment was applied to the patients for 4 hours (AVAPS-BPAP S/T). Then the measurements were repeated. The effects of these NIMV modes on IOP were evaluated.

RESULTS

After NIMV treatment, it was observed that the mean IOP increased statistically significantly (13.3 vs 12.3 mm Hg; P = 0.001). After treatment with NIMV, there was a decrease for CCT close to statistical significance (P = 0.057) CONCLUSION: As a result; increased IOP and thinning of CCT after NIMV treatment has been shown. The type of NIMV and the level of inspiratory pressure needed in hypercapnic respiratory failure seem to affect IOP and it should be cautiously used to increase IOP.

Respiratory Mechanics and Diaphragmatic Dysfunction in COPD Patients Who Failed Non-Invasive Mechanical Ventilation

Background

Although non-invasive mechanical ventilation (NIV) is the gold standard treatment for patients with acute exacerbation of COPD (AECOPD) developing respiratory acidosis, failure rates still range from 5% to 40%. Recent studies have shown that the onset of severe diaphragmatic dysfunction (DD) during AECOPD increases risk of NIV failure and mortality in this subset of patients. Although the imbalance between the load and the contractile capacity of inspiratory muscles seems the main cause of AECOPD-induced hypercapnic respiratory failure, data regarding the influence of mechanical derangement on DD in this acute phase are lacking. With this study, we investigate the impact of respiratory mechanics on diaphragm function in AECOPD patients experiencing NIV failure.

Methods

Twelve AECOPD patients with respiratory acidosis admitted to the Respiratory ICU of the University Hospital of Modena from 2017 to 2018 undergoing mechanical ventilation (MV) due to NIV failure were enrolled. Static respiratory mechanics and end-expiratory lung volume (EELV) were measured after 30 mins of volume control mode MV. Subsequently, transdiaphragmatic pressure (Pdi) was calculated by means of a sniff maneuver (Pdisniff) after 30 mins of spontaneous breathing trial. Linear regression analysis and Pearson’s correlation coefficient served to assess associations.

Results

Average Pdisniff was 23.3 cmH₂O (standard deviation 29 cmH₂O) with 3 patients presenting bilateral diaphragm palsy. Pdisniff was directly correlated with static lung elastance (r=0.69, p=0.001) while inverse correlation was found with dynamic intrinsic PEEP (r=−0.73, p=0.007). No significant correlation was found with static intrinsic PEEP (r=−0.55, p=0.06), EELV (r=−0.4, p=0.3), airway resistance (r=−0.2, p=0.54), chest wall, and total elastance (r=−0-01, p=0.96 and r=0.3, p=0.36, respectively). Significant linear inverse correlation was found between Pdisniff and the ratio between Pdi assessed at tidal volume and Pdi sniff (r=−0.82, p=0.02).

Conclusion

The causes of extreme DD in AECOPD patients who experienced NIV failure might be predominantly mechanical, driven by a severe dynamic hyperinflation that overlaps on an elastic lung substrate favoring volume overload.

High-flow nasal cannula oxygen therapy to treat acute respiratory failure in patients with acute exacerbation of idiopathic pulmonary fibrosis

Background:

Some patients with idiopathic pulmonary fibrosis (IPF) develop acute exacerbation (AE-IPF) leading to severe acute respiratory failure (ARF); despite conventional supportive therapy, the mortality rate remains extremely high. The aim of this study was to assess how a treatment algorithm incorporating high-flow nasal cannula (HFNC) oxygen therapy affects the short-term mortality of patients with AE-IPF who develop ARF.

Method and design:

A retrospective cohort analysis was conducted.

Patients and interventions:

The study consisted of 17 patients with AE-IPF admitted to a respiratory intensive care unit (RICU) for ARF managed using a treatment algorithm incorporating HFNC. The outcome measure was mortality rate during their stay in the RICU.

Results:

Implementation of the treatment algorithm led to a successful outcome in nine patients and to a negative one in eight patients (47.1%) who died within 39 days of being admitted to the RICU. The survival rate was 70.6% (±0.1 %) at 15 days, 52.9% (±0.1%) at 30 days, 35.3% (±0.1%) at 90 days, and 15.6% (±9.73 %) at 365 days. Overall, 4 out of 10 patients who did not respond to conventional oxygen therapy showed a satisfactory response to HFNC.

Conclusions:

Short-term mortality fell to below 50% when a treatment algorithm incorporating HFNC was implemented in a group of patients with AE-IPF admitted to a RICU for ARF. Patients not responding to conventional oxygen therapy seemed to benefit from HFNC.

The reviews of this paper are available via the supplementary material section.

Trends in the Use and Outcomes of Mechanical Ventilation among Patients Hospitalized with Acute Exacerbations of COPD in Spain, 2001 to 2015

(1) Background: We examine trends (2001–2015) in the use of non-invasive ventilation (NIV) and invasive mechanical ventilation (IMV) among patients hospitalized for acute exacerbation of chronic obstructive pulmonary disease (AE-COPD). (2) Methods: Observational retrospective epidemiological study, using the Spanish National Hospital Discharge Database. (3) Results: We included 1,431,935 hospitalizations (aged ≥40 years) with an AE-COPD. NIV use increased significantly, from 1.82% in 2001–2003 to 8.52% in 2013–2015, while IMV utilization decreased significantly, from 1.39% in 2001–2003 to 0.67% in 2013–2015. The use of NIV + invasive mechanical ventilation (IMV) rose significantly over time (from 0.17% to 0.42%). Despite the worsening of clinical profile of patients, length of stay decreased significantly over time in all types of ventilation. Patients who received only IMV had the highest in-hospital mortality (IHM) (32.63%). IHM decreased significantly in patients with NIV + IMV, but it remained stable in those receiving isolated NIV and isolated IMV. Factors associated with use of any type of ventilatory support included female sex, lower age, and higher comorbidity. (4) Conclusions: We found an increase in NIV use and a decline in IMV utilization to treat AE-COPD among hospitalized patients. The IHM decreased significantly over time in patients who received NIV + IMV, but it remained stable in patients who received NIV or IMV in isolation.

Trends in epidemiology and outcomes of respiratory distress syndrome in the United States

BACKGROUND

The management practices of Respiratory Distress Syndrome (RDS) in the newborn have changed over time. We examine the trends in the epidemiology, resource utilization, and outcomes (mortality and bronchopulmonary dysplasia [BPD]) of RDS in preterm neonates ≤34 weeks gestational age (GA) in the United States.

METHODS

In this retrospective serial cross-sectional study, we used ICD-9 codes to classify preterm infants GA ≤34 weeks between 2003 and 2014 from the National Inpatient Sample as having RDS or not. Trends in the prevalence of infants defined as RDS by ICD-9 code (ICD9-RDS), length of stay, BPD, and mortality were analyzed using Cochran-Armitage and Jonckheere-Terpstra tests and multivariable logistic regression.

RESULTS

Of 1 526 186 preterm live births with GA ≤34 weeks, 554 409 had ICD9-RDS (260 cases per 1000 live births) with the prevalence increasing from 170 to 361 (P_trend  < 0.001) and associated decrease in all-cause mortality (7.6% to 6.1%; P_trend  < 0.001) from 2003 to 2014. Increased utilization of non-invasive mechanical ventilation (NIMV) (69.5% to 74.3%; P_trend  < 0.001) was associated with decreased invasive mechanical ventilation (IMV) use >96 h (60.4 to 56.6%; P_trend  < 0.001). Exclusive NIMV use increased from 16.8% to 29.1% (P_trend  < 0.0001). BPD incidence decreased from 14% to 12.5% (P_trend  < 0.001). LOS increased from 32 days to 38 days (P_trend  < 0.001) and cost increased from $49,521 to $55,394 (P_trend  < 0.001).

CONCLUSION

From 2003 to 2014, the assigned ICD9-RDS diagnosis, and utilization of NIMV increased and mortality among infants assigned the ICD9-RDS diagnosis decreased. With higher survival, hospital cost increased incrementally, indicating the importance of ongoing analysis of appropriate reimbursement for the care provided at tertiary centers for preterm infants.

Electromyography-Based Respiratory Onset Detection in COPD Patients on Non-Invasive Mechanical Ventilation

To optimize long-term nocturnal non-invasive ventilation in patients with chronic obstructive pulmonary disease, surface diaphragm electromyography (EMGdi) might be helpful to detect patient-ventilator asynchrony. However, visual analysis is labor-intensive and EMGdi is heavily corrupted by electrocardiographic (ECG) activity. Therefore, we developed an automatic method to detect inspiratory onset from EMGdi envelope using fixed sample entropy (fSE) and a dynamic threshold based on kernel density estimation (KDE). Moreover, we combined fSE with adaptive filtering techniques to reduce ECG interference and improve onset detection. The performance of EMGdi envelopes extracted by applying fSE and fSE with adaptive filtering was compared to the root mean square (RMS)-based envelope provided by the EMG acquisition device. Automatic onset detection accuracy, using these three envelopes, was evaluated through the root mean square error (RMSE) between the automatic and mean visual onsets (made by two observers). The fSE-based method provided lower RMSE, which was reduced from 298 ms to 264 ms when combined with adaptive filtering, compared to 301 ms provided by the RMS-based method. The RMSE was negatively correlated with the proposed EMGdi quality indices. Following further validation, fSE with KDE, combined with adaptive filtering when dealing with low quality EMGdi, indicates promise for detecting the neural onset of respiratory drive.

Predictors of prolonged mechanical ventilation in patients admitted to intensive care units: A systematic review

OBJECTIVE

Although intensive care medicine has evidenced a significant growth in recent decades, the number of patients requiring prolonged mechanical ventilation (PMV) still represents a considerable burden on health-care expenditure. The prediction of the need for PMV seems to provide a plausible cost-effective intervention. The objective of this study is to systematically review the predictors of the need for PMV of adult patients admitted to intensive care units (ICUs) due to medical and surgical needs.

METHODS

We conducted a systematic search on three online databases (PubMed, Embase, and MEDLINE) till February 20, 2019. The search process employed several combinations of specific keywords and Boolean operators.

RESULTS

A total of 15 articles were included in the study. Based on pooling the outcomes of odds ratios (ORs) and their respective 95% confidence intervals (CIs) as reported from logistic regression analyses, the pooled PMV incidence in 8220 patients (69.59% males) was 17.67 cases per 100 ICU admissions (95% CI 13.69-21.65). We could not conduct a meta-analysis of ORs and 95% CIs due to the significant heterogeneity observed between the included studies (P < 0.001, I2 = 97%). Pre-operative/preadmission kidney dysfunction and chronic obstructive pulmonary disease were the most significant independent predictors of the need for PMV. Following cardiac surgeries, repeated or emergency surgery, prolonged cardiopulmonary bypass time, and the need for blood transfusion were predictors of the need for PMV.

CONCLUSION

Within the study limitations, several predictors were identified, which could be further investigated using a unified PMV definition. Successful prediction of the need for PMV would assist clinicians in identifying and adjusting a "weaning strategy" as well as improving patient care to reduce morbidity. Furthermore, establishing specialized weaning units could be warranted based on PMV incidence and prediction in the local settings.

Severity of acidosis affects long-term survival in COPD patients with hypoxemia after intensive care unit discharge

Background

Patients admitted to the intensive care unit (ICU) with acute respiratory failure (ARF) due to COPD have high mortality and morbidity. Acidosis has several harmful effects on hemodynamics and metabolism, and the current knowledge regarding the relationship between respiratory acidosis severity on the short- and long-term survival of COPD patients is limited. We hypothesized that COPD patients with severe acidosis would have a poorer short- and long-term prognosis compared with COPD patients with mild-to-moderate acidosis.

Patients and methods

This retrospective observational cohort study was conducted in a level III respiratory ICU of a tertiary teaching hospital for chest diseases between December 1, 2013, and December 30, 2014. Subject characteristics, comorbidities, ICU parameters, duration of mechanical ventilation, length of ICU stay, ICU mortality, use of domiciliary noninvasive mechanical ventilation (NIMV) and long-term oxygen therapy (LTOT), and short- and long-term mortality were recorded. Patients were grouped according to their arterial blood gas (ABG) values during ICU admission: severe acidotic (pH≤7.20) and mild-to-moderate acidotic (pH 7.21–7.35). These groups were compared with the recorded data. The mortality predictors were analyzed by logistic regression test in the ICU and the Cox regression test for long-term mortality predictors.

Results

During the study period, a total of 312 COPD patients admitted to the ICU with ARF, 69 (72.5% male) in the severe acidosis group and 243 (79% male) in the mild-to-moderate acidosis group, were enrolled. Group demographics, comorbidities, duration of mechanical ventilation, and length of ICU stay were similar in the two groups. The severe acidosis group had a significantly higher rate of NIMV failure (60.7% vs 40%) in the ICU. Mild-to-moderate acidotic COPD patients using LTOT had longer survival after ICU discharge than those without LTOT. On the other hand, severely acidotic COPD patients without LTOT showed shorter survival than those with LTOT. Kaplan–Meier cumulative survival analysis showed that the 28-day and 1-, 2-, and 3-year mortality rates were 12.2%, 36.2%, 52.6%, 63.3%, respectively (p=0.09). The Cox regression analyses showed that older age, PaO₂/FiO₂ <300 mmHg, and body mass index ≤20 kg/m² was associated with mortality of all patients after 3 years.

Conclusion

Severely acidotic COPD patients had a poorer short- and long-term prognosis compared with mild-to-moderate acidotic COPD patients if acute and chronic hypoxemia was predominant.

COPD 2017: A Year in Review

In this review, we focused on original manuscripts published in the 2017 that provided additional information on the clinical and therapeutic features of the chronic obstructive pulmonary disease (COPD). We have chosen eight of these studies, collected in four topics concerning the pharmacological treatment (tiotropium) of mild-moderate patients, the pharmacological (fluticasone furoate/vilanterol/umeclidinium) and non-pharmacological treatment (non-invasive mechanical ventilation) of severe patients, the etiology of acute exacerbation of COPD involving seasonal airway pathogens and the role of eosinophils with particular interest to the monoclonal antibody directed against interleukin-5 (mepolizumab). For each topic, we report a brief description of studies, take-home messages, and brief comments.

Effects of Modes, Obesity, and Body Position on Non-invasive Positive Pressure Ventilation Success in the Intensive Care Unit: A Randomized Controlled Study

OBJECTIVES

Different outcomes and success rates of non-invasive positive pressure ventilation (NPPV) in patients with acute hypercapnic respiratory failure (AHRF) still pose a significant problem in intensive care units. Previous studies investigating different modes, body positioning, and obesity-associated hypoventilation in patients with chronic respiratory failure showed that these factors may affect ventilator mechanics to achieve a better minute ventilation. This study tried to compare pressure support (BiPAP-S) and average volume targeted pressure support (AVAPS-S) modes in patients with acute or acute-on-chronic hypercapnic respiratory failure. In addition, short-term effects of body position and obesity within both modes were analyzed.

MATERIAL and METHODS

We conducted a randomized controlled study in a 7-bed intensive care unit. The course of blood gas analysis and differences in ventilation variables were compared between BiPAP-S (n=33) and AVAPS-S (n=29), and between semi-recumbent and lateral positions in both modes.

RESULTS

No difference was found in the length of hospital stay and the course of PaCO2, pH, and HCO3 levels between the modes. There was a mean reduction of 5.7±4.1 mmHg in the PaCO2 levels in the AVAPS-S mode, and 2.7±2.3 mmHg in the BiPAP-S mode per session (p<0.05). Obesity didn't have any effect on the course of PaCO2 in both the modes. Body positioning had no notable effect in both modes.

CONCLUSION

Although the decrease in the PaCO2 levels in the AVAPS-S mode per session was remarkably high, the course was similar in both modes. Furthermore, obesity and body positioning had no prominent effect on the PaCO2 response and ventilator mechanics. Post hoc power analysis showed that the sample size was not adequate to detect a significant difference between the modes.

Extracorporeal carbon dioxide removal in acute exacerbations of chronic obstructive pulmonary disease

Extracorporeal carbon dioxide removal (ECCO2R) has been proposed as an adjunctive intervention to avoid worsening respiratory acidosis, thereby preventing or shortening the duration of invasive mechanical ventilation (IMV) in patients with exacerbation of chronic obstructive pulmonary disease (COPD). This review will present a comprehensive summary of the pathophysiological rationale and clinical evidence of ECCO2R in patients suffering from severe COPD exacerbations.

Pediatric Respiratory Support Technology and Practices: A Global Survey

Objective: This global survey aimed to assess the current respiratory support capabilities for children with hypoxemia and respiratory failure in different economic settings. Methods: An online, anonymous survey of medical providers with experience in managing pediatric acute respiratory illness was distributed electronically to members of the World Federation of Pediatric Intensive and Critical Care Society, and other critical care websites for 3 months. Results: The survey was completed by 295 participants from 64 countries, including 28 High-Income (HIC) and 36 Low- and Middle-Income Countries (LMIC). Most respondents (≥84%) worked in urban tertiary care centers. For managing acute respiratory failure, endotracheal intubation with mechanical ventilation was the most commonly reported form of respiratory support (≥94% in LMIC and HIC). Continuous Positive Airway Pressure (CPAP) was the most commonly reported form of non-invasive positive pressure support (≥86% in LMIC and HIC). Bubble-CPAP was used by 36% HIC and 39% LMIC participants. ECMO for acute respiratory failure was reported by 45% of HIC participants, compared to 34% of LMIC. Oxygen, air, gas humidifiers, breathing circuits, patient interfaces, and oxygen saturation monitoring appear widely available. Reported ICU patient to health care provider ratios were higher in LMIC compared to HIC. The frequency of respiratory assessments was hourly in HIC, compared to every 2–4 h in LMIC. Conclusions: This survey indicates many apparent similarities in the presence of respiratory support systems in urban care centers globally, but system quality, quantity, and functionality were not established by this survey. LMIC ICUs appear to have higher patient to medical staff ratios, with decreased patient monitoring frequencies, suggesting patient safety should be a focus during the introduction of new respiratory support devices and practices.

Prevalence and outcomes of diaphragmatic dysfunction assessed by ultrasound technology during acute exacerbation of COPD: A pilot study

BACKGROUND AND OBJECTIVE

The prevalence and clinical consequences of diaphragmatic dysfunction (DD) during acute exacerbations of COPD (AECOPD) remain unknown. The aim of this study was (i) to evaluate the prevalence of DD as assessed by ultrasonography (US) and (ii) to report the impact of DD on non-invasive mechanical ventilation (NIV) failure, length of hospital stay and mortality in severe AECOPD admitted to respiratory intensive care unit (RICU).

METHODS

Forty-one consecutive AECOPD patients with respiratory acidosis admitted over a 12-month period to the RICU of the University Hospital of Modena were studied. Diaphragmatic ultrasound (DU) was performed on admission before starting NIV. A change in diaphragmatic thickness (ΔTdi) less than 20% during spontaneous breathing was considered to confirm the presence of dysfunction (DD+). NIV failure and other clinical outcomes (duration of mechanical ventilation MV, tracheostomy, length of hospital stay and mortality) were recorded.

RESULTS

A total of 10 out of 41 patients (24.3%) presented DD+, which was significantly associated with steroid use (P = 0.002, R-squared = 0.19). DD+ correlated with NIV failure (P < 0.001, R-squared = 0.27), longer intensive care unit (ICU) stay (P = 0.02, R-squared = 0.13), prolonged MV (P = 0.023, R-squared = 0.15) and need for tracheostomy (P = 0.006, R-squared = 0.20). Moreover, the Kaplan-Meyer survival estimates showed that NIV failure (log-rank test P value = 0.001, HR = 8.09 (95% CI: 2.7-24.2)) and mortality in RICU (log-rank test P value = 0.039, HR = 4.08 (95% CI: 1.0-16.4)) were significantly associated with DD+.

CONCLUSION

In hospitalized AECOPD patients submitted to NIV, severe DD was seen in almost one-quarter of patients. DD may cause NIV failure, and impacts on the use of clinical resources and on the patient's short-term mortality.

Efficacy of non-invasive mechanical ventilation in the general ward in patients with chronic obstructive pulmonary disease admitted for hypercapnic acute respiratory failure and pH < 7.35: a feasibility pilot study

AIM

To date non-invasive (NIV) mechanical ventilation use is not recommended in chronic obstructive pulmonary disease (COPD) patients with acute respiratory failure (ARF) and pH < 7.30 outside a 'protected environment'. We assessed NIV efficacy and feasibility in improving arterial blood gases (ABG) and in-hospital outcome in patients with ARF and severe respiratory acidosis (RA) admitted to an experienced rural medical ward.

METHODS

This paper is a prospective pilot cohort study conducted in the General Medicine Ward of Budrio's District Hospital. Two hundred and seventy-two patients with ARF were admitted to our Department, 112, meeting predefined inclusion criteria (pH < 7.35, PaCO2 > 45 mmHg). Patients were divided according to the severity of acidosis into: group A (pH < 7.26), group B (7.26 ≤ pH < 7.30) and group C (7.30 ≤ pH < 7.35). ABG were assessed at admission, at 2-6 h, 24 h, 48 h and at discharge.

RESULTS

Group A included 55 patients (24 men, mean age: 80.8 ± 8.3 years), group B 31 (12 men, mean age: 80.3 ± 9.4 years) and group C 26 (15 men, mean age: 78.6 ± 9.9 years). ABG improved within the first hours in 92/112 (82%) patients, who were all successfully discharged. Eighteen percent (20/112) of the patients died during the hospital stay, no significant difference emerged in mortality rate (MR) within the groups (23%, 16% and 8%, for groups A, B and C, respectively) and between patients with or without pneumonia: 8/29 (27%) versus 12/83 (14%). On multivariable analysis, only age and Glasgow Coma Scale had an impact on the clinical outcome.

CONCLUSION

In a non-'highly protected' environment such as an experienced medical ward of a rural hospital, NIV is effective not only in patients with mild, but also with severe forms of RA. MR did not vary according to the level of initial pH.

High intensity positive pressure ventilation and long term pulmonary function responses in severe stable COPD. A delicate and difficult balance

Method to improve minute ventilation (MV) during spontaneous breathing (SB) in stable severe chronic obstructive pulmonary disease (COPD) have a great clinical relevant in long term outcome. In this scenario, recommendations of early use of high-Intensity non-invasive Positive pressure Ventilation (HI-NPPV) or intelligent Volume Assured Pressure (iVAP) Support in Hypercapnic COPD have been proposed by safe therapeutics options. We analyze in this letter, Ekkernkamp et al. study that described the effect of HI-NPPV compared with SB on MV in patients receiving long-term treatment. We consider that interpretation of relationships between ABG, functional parameters, and respiratory mechanics reported need clarifications. Further prospective large clinical trials identifying the best mode of ventilation according to the characteristics in severe stable COPD are necessary to balance an effective approach and response on clinical symptoms and long-term effects.

Invasive and non-invasive mechanical ventilation

Early recognition of patients who might potentially require ventilatory support is a key goal of critical care outreach programs and an important skill for all hospital medical staff. Decisions about the initiation and timing of invasive ventilation can be difficult and early discussion with critical care colleagues is essential. Appropriateness of invasive ventilatory support may also be an issue requiring advanced discussion with patients and their families. In the past 10–15 years, the role of non-invasive ventilation (NIV) has expanded, not least in an attempt to minimize the complications inherent with invasive ventilation. As such, NIV is now considered first-line therapy in some conditions (chronic obstructive pulmonary disease, pulmonary oedema, mild-to-moderate hypoxaemic respiratory failure in immunocompromised patients), and a ‘trial of NIV’ is often considered in respiratory failure resulting from an increasingly wide range of causes. When using NIV, the importance of the environment (setting, monitoring and experience of staff) and forward planning cannot be overemphasized. When used for other than the standard indications, NIV should be employed in a high-dependency/intensive care setting only in patients for whom invasive ventilation would be considered.