Management of acute hypercapnic respiratory failure

Is disposable continuous positive airway pressure system effective for the management of acute hypercapnic respiratory failure?

AIM

This study aimed to investigate the effectiveness of disposable continuous positive airway pressure (DCPAP) system in decreasing the partial pressure of carbon dioxide (PaCO2) levels in patients with acute hypercapnic respiratory failure (AHRF).

MATERIAL AND METHODS

This retrospective observational study included patients treated in the emergency department (ED) with respiratory distress and PaCO2 > 45 mmHg. Patients were divided into two groups (DCPAP and non-DCPAP), depending on the treatment received to treat AHRF. The difference between the baseline PaCO2 levels in the first blood gas obtained from patients at the time of admission and the follow-up blood gas after treatment. Then, the calculated PaCO2 decrease was divided by the time elapsed to obtain the rate of decrease in PaCO2 levels in mmHg/min. The statistical analyses were performed using SPSS version 18.0 software. A p value of < 0.05 was considered statistically significant.

RESULTS

A total of 61 patients were included in the study, 31 patients in the DCPAP group and 30 patients in the non-DCPAP group. The mean age of the patients was 74.03 ± 10.04, and the male/female was 23/38. The study demonstrated a statistically significant difference between the DCPAP and non-DCPAP groups in terms of PaCO2 decreasing rate, and it was found to be twice higher in the DCPAP group (0.11 ± 0.07 mmHg/min) than in the non-DCPAP group (0.05 ± 0.06 mmHg/min).

CONCLUSION

The study demonstrated that the treatment of AHRF patients with a DCPAP provides a faster decrease in PaCO2 levels in hypercapnic patients compared to standard medical therapy alone.

High-flow nasal cannula versus non-invasive ventilation for acute hypercapnic respiratory failure in adults: a systematic review and meta-analysis of randomized trials

Background

Non-invasive ventilation (NIV) with bi-level positive pressure ventilation is a first-line intervention for selected patients with acute hypercapnic respiratory failure. Compared to conventional oxygen therapy, NIV may reduce endotracheal intubation, death, and intensive care unit length of stay (LOS), but its use is often limited by patient tolerance and treatment failure. High-flow nasal cannula (HFNC) is a potential alternative treatment in this patient population and may be better tolerated.

Research question

For patients presenting with acute hypercapnic respiratory failure, is HFNC an effective alternative to NIV in reducing the need for intubation?

Methods

We searched EMBASE, MEDLINE, and the Cochrane library from database inception through to October 2021 for randomized clinical trials (RCT) of adults with acute hypercapnic respiratory failure assigned to receive HFNC or NIV. The Cochrane risk-of-bias tool for randomized trials was used to assess risk of bias. We calculated pooled relative risks (RR) for dichotomous outcomes and mean differences (MD) for continuous outcomes, with corresponding 95% confidence intervals (CI) using a random-effects model.

Results

We included eight RCTs (n = 528) in the final analysis. The use of HFNC compared to NIV did not reduce the risk of our primary outcome of mortality (RR 0.86, 95% CI 0.48–1.56, low certainty), or our secondary outcomes including endotracheal intubation (RR 0.80, 95% CI 0.46–1.39, low certainty), or hospital LOS (MD − 0.82 days, 95% CI − 1.83–0.20, high certainty). There was no difference in change in partial pressure of carbon dioxide between groups (MD − 1.87 mmHg, 95% CI − 5.34–1.60, moderate certainty).

Interpretation

The current body of evidence is limited in determining whether HFNC may be either superior, inferior, or equivalent to NIV for patients with acute hypercapnic respiratory failure given imprecision and study heterogeneity. Further studies are needed to better understand the effect of HFNC on this population.

Hypercapnia from Physiology to Practice

Acute hypercapnic ventilatory failure is becoming more frequent in critically ill patients. Hypercapnia is the elevation in the partial pressure of carbon dioxide (PaCO₂) above 45 mmHg in the bloodstream. The pathophysiological mechanisms of hypercapnia include the decrease in minute volume, an increase in dead space, or an increase in carbon dioxide (CO₂) production per sec. They generate a compromise at the cardiovascular, cerebral, metabolic, and respiratory levels with a high burden of morbidity and mortality. It is essential to know the triggers to provide therapy directed at the primary cause and avoid possible complications.

Agreement and Correlation Between Arterial and Venous Blood pH, PO2, PCO2, Lactate, and HCO3

Retracted

Combined Renal-Pulmonary Extracorporeal Support with Low Blood Flow Techniques: A Retrospective Observational Study (CICERO Study)

BACKGROUND

Critically ill patients with acute respiratory failure frequently present concomitant lung and kidney injury, within a multiorgan failure condition due to local and systemic mediators. To face this issue, extracorporeal carbon dioxide removal (ECCO2R) systems have been integrated into continuous renal replacement therapy (CRRT) platforms to provide a combined organ support, with efficient clearance of CO2 with very low extracorporeal blood flows (<400 mL/min).

OBJECTIVES

To evaluate efficacy and safety of combined ECCO2R-CRRT support with PrismaLung®-Prismaflex® in patients affected by hypercapnic respiratory acidosis associated with AKI in a second level intensive care unit.

METHODS

We carried out a retrospective observational study enrolling patients submitted to PrismaLung®-Prismaflex® due to mild to moderate acute respiratory distress syndrome (ARDS) or acute exacerbation of chronic obstructive pulmonary disease (aeCOPD). The primary endpoints were the shift to protective ventilation and extubation of mechanically ventilated patients and the shift to invasive mechanical ventilation of patients receiving noninvasive ventilation (NIV). Clinical-laboratoristic data and operational characteristics of ECCO2R-CRRT were recorded.

RESULTS

Overall, 12/17 patients on mechanical ventilation shifted to protective ventilation, CO2 clearance was satisfactorily maintained during the whole observational period, and pH was rapidly corrected. Treatment prevented NIV failure in 4 out of 5 patients. No treatment-related complications were recorded.

CONCLUSION

ECCO2R-CRRT was effective and safe in patients with aeCOPD and ARDS associated with AKI.

Summary of recommendations and key points of the consensus of Spanish scientific societies (SEPAR, SEMICYUC, SEMES; SECIP, SENEO, SEDAR, SENP) on the use of non-invasive ventilation and high-flow oxygen therapy with nasal cannulas in adult, pediatric, and neonatal patients with severe acute respiratory failure

Non-invasive respiratory support (NIRS) in adult, pediatric, and neonatal patients with acute respiratory failure (ARF) comprises two treatment modalities, non-invasive mechanical ventilation (NIMV) and high-flow nasal cannula (HFNC) therapy. However, experts from different specialties disagree on the benefit of these techniques in different clinical settings. The objective of this consensus was to develop a series of good clinical practice recommendations for the application of non-invasive support in patients with ARF, endorsed by all scientific societies involved in the management of adult and pediatric/neonatal patients with ARF. To this end, the different societies involved were contacted, and they in turn appointed a group of 26 professionals with sufficient experience in the use of these techniques. Three face-to-face meetings were held to agree on recommendations (up to a total of 71) based on a literature review and the latest evidence associated with 3 categories: indications, monitoring and follow-up of NIRS. Finally, the experts from each scientific society involved voted telematically on each of the recommendations. To classify the degree of agreement, an analogue classification system was chosen that was easy and intuitive to use and that clearly stated whether the each NIRS intervention should be applied, could be applied, or should not be applied.

Summary of Recommendations and Key Points of the Consensus of Spanish Scientific Societies (SEPAR, SEMICYUC, SEMES; SECIP, SENEO, SEDAR, SENP) on the Use of Non-Invasive Ventilation and High-Flow Oxygen Therapy with Nasal Cannulas in Adult, Pediatric, and Neonatal Patients With Severe Acute Respiratory Failure

Non-invasive respiratory support (NIRS) in adult, pediatric, and neonatal patients with acute respiratory failure (ARF) comprises two treatment modalities, non-invasive mechanical ventilation (NIMV) and high-flow nasal cannula (HFNC) therapy. However, experts from different specialties disagree on the benefit of these techniques in different clinical settings. The objective of this consensus was to develop a series of good clinical practice recommendations for the application of non-invasive support in patients with ARF, endorsed by all scientific societies involved in the management of adult and pediatric/neonatal patients with ARF. To this end, the different societies involved were contacted, and they in turn appointed a group of 26 professionals with sufficient experience in the use of these techniques. Three face-to-face meetings were held to agree on recommendations (up to a total of 71) based on a literature review and the latest evidence associated with 3 categories: indications, monitoring and follow-up of NIRS. Finally, the experts from each scientific society involved voted telematically on each of the recommendations. To classify the degree of agreement, an analog classification system was chosen that was easy and intuitive to use and that clearly stated whether the each NIRS intervention should be applied, could be applied, or should not be applied.

Noninvasive ventilation and high-flow oxygen therapy for severe community-acquired pneumonia

PURPOSE OF REVIEW

We review the evidence on the use of noninvasive respiratory supports (noninvasive ventilation and high-flow nasal cannula oxygen therapy) in patients with acute respiratory failure because of severe community-acquired pneumonia.

RECENT FINDINGS

Noninvasive ventilation is strongly advised for the treatment of hypercapnic respiratory failure and recent evidence justifies its use in patients with hypoxemic respiratory failure when delivered by helmet. Indeed, such interface allows alveolar recruitment by providing high level of positive end-expiratory pressure, which improves hypoxemia. On the other hand, high-flow nasal cannula oxygen therapy is effective in patients with hypoxemic respiratory failure and some articles support its use in patients with hypercapnia. However, early identification of noninvasive respiratory supports treatment failure is crucial to prevent delayed orotracheal intubation and protective invasive mechanical ventilation.

SUMMARY

Noninvasive ventilation is the first-line therapy in patients with acute hypercapnic respiratory failure because of pneumonia. Although an increasing amount of evidence investigated the application of noninvasive respiratory support to hypoxemic respiratory failure, the optimal ventilatory strategy in this setting is uncertain. Noninvasive mechanical ventilation delivered by helmet and high-flow nasal cannula oxygen therapy appear as promising tools but their role needs to be confirmed by future research.

Summary of Recommendations and Key Points of the Consensus of Spanish Scientific Societies (SEPAR, SEMICYUC, SEMES; SECIP, SENEO, SEDAR, SENP) on the Use of Non-Invasive Ventilation and High-Flow Oxygen Therapy with Nasal Cannulas in Adult, Pediatric, and Neonatal Patients with Severe Acute Respiratory Failure

Non-invasive respiratory support (NIRS) in adult, pediatric, and neonatal patients with acute respiratory failure (ARF) comprises two treatment modalities, non-invasive mechanical ventilation (NIMV) and high-flow nasal cannula (HFNC) therapy. However, experts from different specialties disagree on the benefit of these techniques in different clinical settings. The objective of this consensus was to develop a series of good clinical practice recommendations for the application of non-invasive support in patients with ARF, endorsed by all scientific societies involved in the management of adult and pediatric/neonatal patients with ARF. To this end, the different societies involved were contacted, and they in turn appointed a group of 26 professionals with sufficient experience in the use of these techniques. Three face-to-face meetings were held to agree on recommendations (up to a total of 71) based on a literature review and the latest evidence associated with 3 categories: indications, monitoring and follow-up of NIRS. Finally, the experts from each scientific society involved voted telematically on each of the recommendations. To classify the degree of agreement, an analogue classification system was chosen that was easy and intuitive to use and that clearly stated whether the each NIRS intervention should be applied, could be applied, or should not be applied.

Summary of recommendations and key points of the consensus of Spanish scientific societies (SEPAR, SEMICYUC, SEMES; SECIP, SENEO, SEDAR, SENP) on the use of non-invasive ventilation and high-flow oxygen therapy with nasal cannulas in adult, pediatric, and neonatal patients with severe acute respiratory failure

Non-invasive respiratory support (NIRS) in adult, pediatric, and neonatal patients with acute respiratory failure (ARF) comprises two treatment modalities, non-invasive mechanical ventilation (NIMV) and high-flow nasal cannula (HFNC) therapy. However, experts from different specialties disagree on the benefit of these techniques in different clinical settings. The objective of this consensus was to develop a series of good clinical practice recommendations for the application of non-invasive support in patients with ARF, endorsed by all scientific societies involved in the management of adult and pediatric/neonatal patients with ARF. To this end, the different societies involved were contacted, and they in turn appointed a group of 26 professionals with sufficient experience in the use of these techniques. Three face-to-face meetings were held to agree on recommendations (up to a total of 71) based on a literature review and the latest evidence associated with 3 categories: indications, monitoring and follow-up of NIRS. Finally, the experts from each scientific society involved voted telematically on each of the recommendations. To classify the degree of agreement, an analogue classification system was chosen that was easy and intuitive to use and that clearly stated whether the each NIRS intervention should be applied, could be applied, or should not be applied.

Extubating to Noninvasive Ventilation: Noninvasive Ventilation from Intensive Care Unit to Home

Weaning to noninvasive ventilation in intensive care unit and bridging the patients to home with respiratory support is evolving as the technology of noninvasive ventilation is improving. In patients with chronic obstructive pulmonary disease exacerbation, timing of initiation of noninvasive ventilation is the key, as persistently hypercapnic patients show benefits. High-intensity pressure support seems to do better in comparison to low-intensity pressure support. In patients with obesity and hypercapnia, obesity hypoventilation cannot be ruled out especially in an inpatient setting, and it is crucial that these patients are discharged with noninvasive ventilation.

Dual Carbon Dioxide Capture to Achieve Highly Efficient Ultra-Low Blood Flow Extracorporeal Carbon Dioxide Removal

Extracorporeal CO₂ removal is a highly promising support therapy for patients with hypercapnic respiratory failure but whose clinical implementation and patient benefit is hampered by high cost and highly specialized expertise required for safe use. Current approaches target removal of the gaseous CO₂ dissolved in blood which limits their ease of clinical use as high blood flow rates are required to achieve physiologically significant CO₂ clearance. Here, a novel hybrid approach in which a zero-bicarbonate dialysis is used to target removal of bicarbonate ion coupled to a gas exchange device to clear dissolved CO₂, achieves highly efficiently total CO₂ capture while maintaining systemic acid-base balance. In a porcine model of acute hypercapnic respiratory failure, a CO₂-reduction of 61.4 ± 14.4 mL/min was achieved at a blood flow rate of 248 mL/min using pediatric-scale priming volumes. The dialyzer accounted for 81% of total CO₂ capture with an efficiency of 33% with a minimal pH change across the entire circuit. This study demonstrates the feasibility of a novel hybrid CO₂ capture approach capable of achieving physiologically significant CO₂ removal at ultralow blood flow rates with low priming volumes while leveraging widely available dialysis platforms to enable clinical adoption.

Noninvasive ventilation in acute respiratory failure: which recipe for success?

Noninvasive positive-pressure ventilation (NPPV) to treat acute respiratory failure has expanded tremendously over the world in terms of the spectrum of diseases that can be successfully managed, the locations of its application and achievable goals.

The turning point for the successful expansion of NPPV is its ability to achieve the same physiological effects as invasive mechanical ventilation with the avoidance of the life-threatening risks correlated with the use of an artificial airway.

Cardiorespiratory arrest, extreme psychomotor agitation, severe haemodynamic instability, nonhypercapnic coma and multiple organ failure are absolute contraindications for NPPV. Moreover, pitfalls of NPPV reduce its rate of success; consistently, a clear plan of what to do in case of NPPV failure should be considered, especially for patients managed in unprotected setting. NPPV failure is likely to be reduced by the application of integrated therapeutic tools in selected patients handled by expert teams.

In conclusion, NPPV has to be considered as a rational art and not just as an application of science, which requires the ability of clinicians to both choose case-by-case the best “ingredients” for a “successful recipe” (i.e.patient selection, interface, ventilator, interface,etc.) and to avoid a delayed intubation if the ventilation attempt fails.

Highlights in acute respiratory failure

Acute respiratory failure (ARF) is a devastating condition for patients that results from either impaired function of the respiratory muscle pump or from dysfunction of the lung. ARF is a challenging field for clinicians working both within and outside the intensive care unit (ICU) and respiratory high dependency care unit environment because this heterogeneous syndrome is associated with a high hospital morbidity and mortality rate, ethical issues in managing end of life decisions and increased consumption of healthcare resources.

ARF management requires an escalation therapeutic strategy based on application of a wide range of ventilatory and non-ventilatory interventions; there are many unanswered questions that need to be addressed in the near futurehttp://ow.ly/xbPi30iUP2y

Ten important articles on noninvasive ventilation in critically ill patients and insights for the future: A report of expert opinions

Background

Noninvasive ventilation is used worldwide in many settings. Its effectiveness has been proven for common clinical conditions in critical care such as cardiogenic pulmonary edema and chronic obstructive pulmonary disease exacerbations.

Since the first pioneering studies of noninvasive ventilation in critical care in the late 1980s, thousands of studies and articles have been published on this topic. Interestingly, some aspects remain controversial (e.g. its use in de-novo hypoxemic respiratory failure, role of sedation, self-induced lung injury). Moreover, the role of NIV has recently been questioned and reconsidered in light of the recent reports of new techniques such as high-flow oxygen nasal therapy.

Methods

We conducted a survey among leading experts on NIV aiming to 1) identify a selection of 10 important articles on NIV in the critical care setting 2) summarize the reasons for the selection of each study 3) offer insights on the future for both clinical application and research on NIV.

Results

The experts selected articles over a span of 26 years, more clustered in the last 15 years. The most voted article studied the role of NIV in acute exacerbation chronic pulmonary disease. Concerning the future of clinical applications for and research on NIV, most of the experts forecast the development of innovative new interfaces more adaptable to patients characteristics, the need for good well-designed large randomized controlled trials of NIV in acute “de novo” hypoxemic respiratory failure (including its comparison with high-flow oxygen nasal therapy) and the development of software-based NIV settings to enhance patient-ventilator synchrony.

Conclusions

The selection made by the experts suggests that some applications of NIV in critical care are supported by solid data (e.g. COPD exacerbation) while others are still waiting for confirmation. Moreover, the identified insights for the future would lead to improved clinical effectiveness, new comparisons and evaluation of its role in still “lack of full evidence” clinical settings.

Electronic supplementary material

The online version of this article (10.1186/s12871-017-0409-0) contains supplementary material, which is available to authorized users.

[Update: acute hypercapnic respiratory failure]

BACKGROUND

Hypercapnic respiratory failure is a frequent problem in critical care and mainly affects patients with acute exacerbation of COPD (AECOPD) and acute respiratory distress syndrome (ARDS). In recent years, the usage of extracorporeal CO₂ removal (ECCO₂R) has been increasing.

OBJECTIVE

Summarizing the state of the art in the management of hypercapnic respiratory failure with special regard to the role of ECCO₂R.

METHODS

Review based on a selective literature search and the clinical and scientific experience of the authors.

RESULTS

Noninvasive ventilation (NIV) is the therapy of choice in hypercapnic respiratory failure due to AECOPD, enabling stabilization in the majority of cases and generally improving prognosis. Patients in whom NIV fails have an increased mortality. In these patients, ECCO₂R may be sufficient to avoid intubation or to shorten time on invasive ventilation; however, corresponding evidence is sparse or even missing when it comes to hard endpoints. Lung-protective ventilation according to the ARDS network is the standard therapy of ARDS. In severe ARDS, low tidal volume ventilation may result in critical hypercapnia. ECCO₂R facilitates compensation of respiratory acidosis even under "ultra-protective" ventilator settings. Yet, no positive prognostic effects could be demonstrated so far.

CONCLUSION

Optimized use of NIV and lung-protective ventilation remains standard of care in the management of hypercapnic respiratory failure. Currently, ECCO₂R has to be considered an experimental approach, which should only be provided by experienced centers or in the context of clinical trials.

Current evidence for the effectiveness of heated and humidified high flow nasal cannula supportive therapy in adult patients with respiratory failure

High flow nasal cannula (HFNC) supportive therapy has emerged as a safe, useful therapy in patients with respiratory failure, improving oxygenation and comfort. Recently several clinical trials have analyzed the effectiveness of HFNC therapy in different clinical situations and have reported promising results. Here we review the current knowledge about HFNC therapy, from its mechanisms of action to its effects on outcomes in different clinical situations.