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Canadian Respiratory Journal 2017
Topics: Extracorporeal Membrane Oxygenation; Humans; Hypoxia; Oxygen Inhalation Therapy; Respiration, Artificial; Respiratory Insufficiency
PubMed: 28588381
DOI: 10.1155/2017/2462818 -
Monaldi Archives For Chest Disease =... Nov 2022Oxygen is probably the most commonly prescribed drug in the emergency setting and is a life-saving modality as well. However, like any other drug, oxygen therapy may... (Review)
Review
Oxygen is probably the most commonly prescribed drug in the emergency setting and is a life-saving modality as well. However, like any other drug, oxygen therapy may also lead to various adverse effects. Patients with chronic obstructive pulmonary disease (COPD) may develop hypercapnia during supplemental oxygen therapy, particularly if uncontrolled. The risk of hypercapnia is not restricted to COPD only; it has also been reported in patients with morbid obesity, asthma, cystic fibrosis, chest wall skeletal deformities, bronchiectasis, chest wall deformities, or neuromuscular disorders. However, the risk of hypercapnia should not be a deterrent to oxygen therapy in hypoxemic patients with chronic lung diseases, as hypoxemia may lead to life-threatening cardiovascular complications. Various mechanisms leading to the development of oxygen-induced hypercapnia are the abolition of 'hypoxic drive', loss of hypoxic vasoconstriction and absorption atelectasis leading to an increase in dead-space ventilation and Haldane effect. The international guideline recommends a target oxygen saturation of 88% to 92% in patients with acute exacerbations of chronic obstructive pulmonary disease (AECOPD) and other chronic lung diseases at risk of hypercapnia. Oxygen should be administered only when oxygen saturation is below 88%. We searched PubMed, EMBASE, and the CINAHL from inception to June 2022. We used the following search terms: "Hypercapnia", "Oxygen therapy in COPD", "Oxygen-associated hypercapnia", "oxygen therapy", and "Hypoxic drive". All types of study are selected. This review will focus on the physiological mechanisms of oxygen-induced hypercapnia and its clinical implications.
Topics: Humans; Oxygen; Hypercapnia; Pulmonary Disease, Chronic Obstructive; Oxygen Inhalation Therapy; Lung Diseases; Hypoxia
PubMed: 36412131
DOI: 10.4081/monaldi.2022.2399 -
Respiratory Care Jun 2019For hypoxemic respiratory failure, the frontline treatment is supplemental oxygen. Since ARDS was first described, mechanical ventilation via an endotracheal tube... (Review)
Review
For hypoxemic respiratory failure, the frontline treatment is supplemental oxygen. Since ARDS was first described, mechanical ventilation via an endotracheal tube (invasive ventilation) has no doubt saved many patients. During the 1990s, noninvasive ventilation was found to be superior to invasive ventilation for exacerbations of COPD, acute cardiogenic pulmonary edema, and acute respiratory failure in patients who were immunocompromised. In the 2000s, less invasive high-flow nasal cannula (HFNC) therapy gained attention as an alternative means of respiratory support for patients who were critically ill. The HFNC system is simple: it requires only a flow generator, active heated humidifier, single heated circuit, and nasal cannula. While NIV interfaces add to anatomic dead space, HFNC delivery actually decreases dead space. Although the use of HFNC in adults who are critically ill has been dramatically increasing, the advantages and disadvantages of each element have not been well discussed. For now, although functional differences among the different HFNC systems seem to be minor, to avoid adverse clinical events, it is essential to know the advantages and disadvantages of each element.
Topics: Cannula; Equipment Design; Humans; Oxygen Inhalation Therapy; Respiratory Insufficiency
PubMed: 31110041
DOI: 10.4187/respcare.06718 -
Respiratory Care Jun 2018Long-term oxygen therapy (LTOT) at home has been demonstrated to improve survival in patients with COPD and severe resting hypoxemia. Support for LTOT is based on 2... (Review)
Review
Long-term oxygen therapy (LTOT) at home has been demonstrated to improve survival in patients with COPD and severe resting hypoxemia. Support for LTOT is based on 2 landmark trials published nearly 4 decades ago. These results form the basis for reimbursement and prescription of LTOT to this day. Recent work has demonstrated no outcome benefit of LTOT in stable COPD patients with moderate desaturation at rest or during activity. Oxygen therapy during activity and exercise has been shown to alleviate symptoms and maintain arterial oxygen saturation, but not improve long-term outcomes. Oxygen therapy in COPD has a number of physiologic, functional, and biologic effects, not all of which are completely understood. Oxygen therapy in exacerbations of COPD can be both helpful and harmful. New guidance on the use of oxygen therapy during pre-hospital care has been published in the United Kingdom. Technology for LTOT represents a challenge for physicians writing prescriptions, durable medical equipment suppliers, caregivers, and patients. New technology for automated control of LTOT shows promise but is hampered by regulatory processes and cost pressures. Recent changes in government reimbursement for home oxygen therapy also present challenges. This paper will review the current evidence regarding LTOT in COPD and the impact on mortality and functional outcomes as well as reviewing technological challenges.
Topics: Female; Humans; Hypoxia; Male; Oxygen Inhalation Therapy; Pulmonary Disease, Chronic Obstructive; Quality of Life; Treatment Outcome
PubMed: 29794207
DOI: 10.4187/respcare.06312 -
Respiratory Care Apr 2016High-flow nasal cannula (HFNC) oxygen therapy is carried out using an air/oxygen blender, active humidifier, single heated tube, and nasal cannula. Able to deliver... (Review)
Review
High-flow nasal cannula (HFNC) oxygen therapy is carried out using an air/oxygen blender, active humidifier, single heated tube, and nasal cannula. Able to deliver adequately heated and humidified medical gas at flows up to 60 L/min, it is considered to have a number of physiological advantages compared with other standard oxygen therapies, including reduced anatomical dead space, PEEP, constant F(IO2), and good humidification. Although few large randomized clinical trials have been performed, HFNC has been gaining attention as an alternative respiratory support for critically ill patients. Published data are mostly available for neonates. For critically ill adults, however, evidence is uneven because the reports cover various subjects with diverse underlying conditions, such as hypoxemic respiratory failure, exacerbation of COPD, postextubation, preintubation oxygenation, sleep apnea, acute heart failure, and conditions entailing do-not-intubate orders. Even so, across the diversity, many published reports suggest that HFNC decreases breathing frequency and work of breathing and reduces the need for respiratory support escalation. Some important issues remain to be resolved, such as definitive indications for HFNC and criteria for timing the starting and stopping of HFNC and for escalating treatment. Despite these issues, HFNC has emerged as an innovative and effective modality for early treatment of adults with respiratory failure with diverse underlying diseases.
Topics: Adult; Cannula; Critical Illness; Female; Humans; Humidity; Male; Nose; Oxygen; Oxygen Inhalation Therapy; Respiratory Insufficiency; Work of Breathing
PubMed: 27016353
DOI: 10.4187/respcare.04577 -
Respiratory Care Jul 2021Hypoxemia is common in postoperative patients and is associated with prolonged hospital stays, high costs, and increased mortality. This review discusses the... (Review)
Review
Hypoxemia is common in postoperative patients and is associated with prolonged hospital stays, high costs, and increased mortality. This review discusses the postoperative management of hypoxemia in regard to the use of conventional oxygen therapy, high-flow nasal cannula oxygen therapy, CPAP, and noninvasive ventilation. The recommendations made are based on the currently available evidence.
Topics: Cannula; Continuous Positive Airway Pressure; Humans; Hypoxia; Noninvasive Ventilation; Oxygen; Oxygen Inhalation Therapy
PubMed: 34006596
DOI: 10.4187/respcare.08929 -
The New England Journal of Medicine Jun 2015Whether noninvasive ventilation should be administered in patients with acute hypoxemic respiratory failure is debated. Therapy with high-flow oxygen through a nasal... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Whether noninvasive ventilation should be administered in patients with acute hypoxemic respiratory failure is debated. Therapy with high-flow oxygen through a nasal cannula may offer an alternative in patients with hypoxemia.
METHODS
We performed a multicenter, open-label trial in which we randomly assigned patients without hypercapnia who had acute hypoxemic respiratory failure and a ratio of the partial pressure of arterial oxygen to the fraction of inspired oxygen of 300 mm Hg or less to high-flow oxygen therapy, standard oxygen therapy delivered through a face mask, or noninvasive positive-pressure ventilation. The primary outcome was the proportion of patients intubated at day 28; secondary outcomes included all-cause mortality in the intensive care unit and at 90 days and the number of ventilator-free days at day 28.
RESULTS
A total of 310 patients were included in the analyses. The intubation rate (primary outcome) was 38% (40 of 106 patients) in the high-flow-oxygen group, 47% (44 of 94) in the standard group, and 50% (55 of 110) in the noninvasive-ventilation group (P=0.18 for all comparisons). The number of ventilator-free days at day 28 was significantly higher in the high-flow-oxygen group (24±8 days, vs. 22±10 in the standard-oxygen group and 19±12 in the noninvasive-ventilation group; P=0.02 for all comparisons). The hazard ratio for death at 90 days was 2.01 (95% confidence interval [CI], 1.01 to 3.99) with standard oxygen versus high-flow oxygen (P=0.046) and 2.50 (95% CI, 1.31 to 4.78) with noninvasive ventilation versus high-flow oxygen (P=0.006).
CONCLUSIONS
In patients with nonhypercapnic acute hypoxemic respiratory failure, treatment with high-flow oxygen, standard oxygen, or noninvasive ventilation did not result in significantly different intubation rates. There was a significant difference in favor of high-flow oxygen in 90-day mortality. (Funded by the Programme Hospitalier de Recherche Clinique Interrégional 2010 of the French Ministry of Health; FLORALI ClinicalTrials.gov number, NCT01320384.).
Topics: Acute Disease; Adult; Aged; Female; Humans; Hypoxia; Intubation, Intratracheal; Kaplan-Meier Estimate; Male; Middle Aged; Oxygen; Oxygen Inhalation Therapy; Positive-Pressure Respiration; Respiratory Insufficiency
PubMed: 25981908
DOI: 10.1056/NEJMoa1503326 -
Respiratory Care Jun 2017Oxygen is a colorless, odorless, tasteless gas that is utilized by the body for respiration. Oxygen has played a major role in respiratory care. Oxygen therapy is useful... (Review)
Review
Oxygen is a colorless, odorless, tasteless gas that is utilized by the body for respiration. Oxygen has played a major role in respiratory care. Oxygen therapy is useful in treating hypoxemia but is often thought of as a benign therapy. After many years of study, we have learned a great deal of the benefits and potential risk of this powerful drug. Today oxygen gas is cheap, widely available, and easy to administer. Oxygen delivery devices vary in cost from a few cents for a simple nasal cannula to $25-$50 for some humidified systems. Undoubtedly, oxygen therapy is an important tool and has saved many lives and improved others. However, oxygen therapy risk, cost, and benefits should be considered in the same way as other drugs and titrated to a measured end point to avoid excessive or inadequate dosing. Withholding oxygen can have a detrimental effect, yet continuing to provide oxygen therapy when it is no longer indicated can prolong hospitalization and increase the cost of care. This comprehensive review begins with an assessment of need and a review of physiologic effects, potential toxicities, and common delivery devices, and it ends with advances in oxygen therapy with a focus on the pediatric patient.
Topics: Administration, Inhalation; Child; Humans; Hypoxia; Oxygen; Oxygen Inhalation Therapy
PubMed: 28546370
DOI: 10.4187/respcare.05245 -
American Journal of Respiratory and... Sep 2021Oxygen supplementation is one of the most common interventions in critically ill patients. Despite over a century of data suggesting both beneficial and detrimental... (Review)
Review
Oxygen supplementation is one of the most common interventions in critically ill patients. Despite over a century of data suggesting both beneficial and detrimental effects of supplemental oxygen, optimal arterial oxygenation targets in adult patients remain unclear. Laboratory animal studies have consistently showed that exposure to a high Fi causes respiratory failure and early death. Human autopsy studies from the 1960s purported to provide histologic evidence of pulmonary oxygen toxicity in the form of diffuse alveolar damage. However, concomitant ventilator-induced lung injury and/or other causes of acute lung injury may explain these findings. Although some observational studies in general populations of critically adults showed higher mortality in association with higher oxygen exposures, this finding has not been consistent. For some specific populations, such as those with cardiac arrest, studies have suggested harm from targeting supraphysiologic Pa levels. More recently, randomized clinical trials of arterial oxygenation targets in narrower physiologic ranges were conducted in critically ill adult patients. Although two smaller trials came to opposite conclusions, the two largest of these trials showed no differences in clinical outcomes in study groups that received conservative versus liberal oxygen targets, suggesting that either strategy is reasonable. It is possible that some strategies are of benefit in some subpopulations, and this remains an important ongoing area of research. Because of the ubiquity of oxygen supplementation in critically ill adults, even small treatment effects could have a large impact on a global scale.
Topics: Adult; Animals; Critical Care; Critical Illness; Humans; Hyperoxia; Oxygen; Oxygen Inhalation Therapy; Respiratory Insufficiency
PubMed: 34086536
DOI: 10.1164/rccm.202102-0417CI -
Intensive Care Medicine Feb 2022Systematic review and network meta-analysis to investigate the efficacy of noninvasive respiratory strategies, including noninvasive positive pressure ventilation... (Meta-Analysis)
Meta-Analysis
PURPOSE
Systematic review and network meta-analysis to investigate the efficacy of noninvasive respiratory strategies, including noninvasive positive pressure ventilation (NIPPV) and high-flow nasal cannula (HFNC), in reducing extubation failure among critically ill adults.
METHODS
We searched databases from inception through October 2021 for randomized controlled trials (RCTs) evaluating noninvasive respiratory support therapies (NIPPV, HFNC, conventional oxygen therapy, or a combination of these) following extubation in critically ill adults. Two reviewers performed screening, full text review, and extraction independently. The primary outcome of interest was reintubation. We used GRADE to rate the certainty of our findings.
RESULTS
We included 36 RCTs (6806 patients). Compared to conventional oxygen therapy, NIPPV (OR 0.65 [95% CI 0.52-0.82]) and HFNC (OR 0.63 [95% CI 0.45-0.87]) reduced reintubation (both moderate certainty). Sensitivity analyses showed that the magnitude of the effect was highest in patients with increased baseline risk of reintubation. As compared to HFNC, no difference in incidence of reintubation was seen with NIPPV (OR 1.04 [95% CI 0.78-1.38], low certainty). Compared to conventional oxygen therapy, neither NIPPV (OR 0.8 [95% CI 0.61-1.04], moderate certainty) or HFNC (OR 0.9 [95% CI 0.66-1.24], low certainty) reduced short-term mortality. Consistent findings were demonstrated across multiple subgroups, including high- and low-risk patients. These results were replicated when evaluating noninvasive strategies for prevention (prophylaxis), but not in rescue (application only after evidence of deterioration) situations.
CONCLUSIONS
Our findings suggest that both NIPPV and HFNC reduced reintubation in critically ill adults, compared to conventional oxygen therapy. NIPPV did not reduce incidence of reintubation when compared to HFNC. These findings support the preventative application of noninvasive respiratory support strategies to mitigate extubation failure in critically ill adults, but not in rescue conditions.
Topics: Adult; Airway Extubation; Cannula; Critical Illness; Humans; Network Meta-Analysis; Noninvasive Ventilation; Oxygen Inhalation Therapy; Respiratory Insufficiency
PubMed: 34825256
DOI: 10.1007/s00134-021-06581-1