Early prediction of extracorporeal membrane oxygenation eligibility for severe acute respiratory distress syndrome in adults

Outcomes of extracorporeal life support for respiratory failure in children with primary immunodeficiencies

OBJECTIVE

Extracorporeal Membrane Oxygenation (ECMO) may serve as a life-saving rescue therapy in critically ill children with respiratory failure. While survival rates of ECMO in children with secondary immunodeficiency is considered relatively poor, survival rates in children with primary immunodeficiencies (PID) has yet to be thoroughly investigated.

DESIGN

Retrospective analysis of prospectively collected data from children (29 days-18 years old). PID patients were identified by using International Classification of Diseases (ICD) codes.

SETTING

Data were retrieved from Extracorporeal Life Support Organization Registry (1989-2018).

INTERVENTIONS

ECMO for a pulmonary support indication. The survival-to-discharge rate was calculated and factors influencing outcomes were compared between survivors and non-survivors.

MEASUREMENTS AND MAIN RESULTS

A total of 73 eligible ECMO runs were included. The survival-to-discharge rate in pediatric PID patients was 45.2%. No differences were noted in survival based on type of immunodeficiency (p = 0.42) or decade of support (p = 0.98). There was no difference in the rate of pre-ECMO infection in survivors versus non-survivors (p = 0.69). The survival-to-discharge rate in patients with a culture positive infection during the ECMO run was 45.0% versus 45.3% in those with no infection (p = 0.98). In multivariate analysis, only cardiac complications (OR 5.09, 95% CI: 1.15-22.53), pulmonary complications (OR: 13.00, 95% CI: 1.20-141.25), and neurologic complications (OR: 9.86, 95% CI: 1.64-59.21) were independently associated with increased mortality.

CONCLUSION

Children with a PID who require extracorporeal life support due to respiratory failure have a reasonable chance of survival and should be considered candidates for ECMO. The presence of a pre-ECMO infection should not be considered an ECMO contraindication.

Evolution of Acute Respiratory Distress Syndrome in Emergency and Critical Care: Therapeutic Management before and during the Pandemic Situation

Background and Objectives: Acute respiratory distress syndrome is a life-threatening lung condition that prevents enough oxygen from getting to the lungs and blood. The causes can be varied, although since the COVID-19 pandemic began there have been many cases related to this virus. The management and evolution of ARDS in emergency situations in the last 5 years was analyzed. Materials and Methods: A systematic review was carried out in the PubMed and Scopus databases. Using the descriptors Medical Subject Headings (MeSH), the search equation was: “Emergency health service AND acute respiratory distress syndrome”. The search was conducted in December 2021. Quantitative primary studies on the care of patients with ARDS in an emergency setting published in the last 5 years were included. Results: In the initial management, adherence to standard treatment with continuous positive airway pressure (CPAP) is recommended. The use of extracorporeal membrane reduces the intensity of mechanical ventilation or as rescue therapy in acute respiratory distress syndrome (ARDS). The prone position in both intubated and non-intubated patients with severe ARDS is associated with a better survival of these patients, therefore, it is very useful in these moments of pandemic crisis. Lack of resources forces triage decisions about which patients are most likely to survive to start mechanical ventilation and this reflects the realities of intensive care and emergency care in a resource-limited setting. Conclusions: adequate prehospital management of ARDS and in emergency situations can improve the prognosis of patients. The therapeutic options in atypical ARDS due to COVID-19 do not seem to vary substantially from conventional ARDS.

Practices in Triage and Transfer of Critically Ill Patients: A Qualitative Systematic Review of Selection Criteria

OBJECTIVES

To identify and appraise articles describing criteria used to prioritize or withhold a critical care admission.

DATA SOURCES

PubMed, Embase, Medline, EBM Reviews, and CINAHL Complete databases. Gray literature searches and a manual review of references were also performed. Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines were followed.

STUDY SELECTION

We sought all articles and abstracts of original research as well as local, provincial, or national policies on the topic of ICU resource allocation. We excluded studies whose population of interest was neonatal, pediatric, trauma, or noncritically ill. Screening of 6,633 citations was conducted.

DATA EXTRACTION

Triage and/or transport criteria were extracted, based on type of article, methodology, publication year, and country. An appraisal scale was developed to assess the quality of identified articles. We also developed a robustness score to further appraise the robustness of the evidence supporting each criterion. Finally, all criteria were extracted, evaluated, and grouped by theme.

DATA SYNTHESIS

One-hundred twenty-nine articles were included. These were mainly original research (34%), guidelines (26%), and reviews (21%). Among them, we identified 200 unique triage and transport criteria. Most articles highlighted an exclusion (71%) rather than a prioritization mechanism (17%). Very few articles pertained to transport of critically ill patients (4%). Criteria were classified in one of four emerging themes: patient, condition, physician, and context. The majority of criteria used were nonspecific. No study prospectively evaluated the implementation of its cited criteria.

CONCLUSIONS

This systematic review identified 200 criteria classified within four themes that may be included when devising triage programs including the coronavirus disease 2019 pandemic. We identified significant knowledge gaps where research would assist in improving existing triage criteria and guidelines, aiming to decrease arbitrary decisions and variability.

National trends in volume-outcome relationships for extracorporeal membrane oxygenation

BACKGROUND

The use of extracorporeal membrane oxygenation (ECMO) has emerged as a common therapy for severe cardiopulmonary dysfunction. We aimed to describe the relationship of institutional volume with patient outcomes and examine transfer status to tertiary ECMO centers.

MATERIALS AND METHODS

Using the National Inpatient Sample, we identified adult patients who received ECMO from 2008 to 2014. Individual hospital volume was calculated as tertiles of total institutional discharges for each year independently.

RESULTS

Of the total 18,684 adult patients placed on ECMO, 2548 (13.6%), 5278 (28.2%), and 10,858 (58.1%) patients were admitted to low-, medium-, and high-volume centers, respectively. Unadjusted mortality at low-volume hospitals was less than that of medium- (43.7% versus 50.3%, P = 0.03) and high-volume hospitals (43.7% versus 55.6%, P < 0.001). Length of stay and cost were reduced at low-volume hospitals compared to both medium- and large-volume institutions (all P < 0.001). In high-volume institutions, transferred patients had greater postpropensity-matched mortality (58.5% versus 53.7%, P = 0.05) and cost ($190,299 versus $168,970, P = 0.009) compared to direct admissions. On exclusion of transferred patients from propensity analysis, mortality remained greater in high-volume compared to low-volume centers (50.2% versus 42.8%, P = 0.04). Predictors of mortality included treatment at high-volume centers, respiratory failure, and cardiogenic shock (all P < 0.001).

CONCLUSIONS

Our findings show increased in-hospital mortality in high-volume institutions and in patients transferred to tertiary centers. Whether this phenomenon represents selection bias or transfer from another facility deserves further investigation and will aid with the identification of surrogate markers for quality of high-risk interventions.

Update in Management of Severe Hypoxemic Respiratory Failure

Mortality related to severe-moderate and severe ARDS remains high. We searched the literature to update this topic. We defined severe hypoxemic respiratory failure as Pao₂/Fio₂ < 150 mm Hg (ie, severe-moderate and severe ARDS). For these patients, we support setting the ventilator to a tidal volume of 4 to 8 mL/kg predicted body weight (PBW), with plateau pressure (Pplat) ≤ 30 cm H₂O, and initial positive end-expiratory pressure (PEEP) of 10 to 12 cm H₂O. To promote alveolar recruitment, we propose increasing PEEP in increments of 2 to 3 cm provided that Pplat remains ≤ 30 cm H₂O and driving pressure does not increase. A fluid-restricted strategy is recommended, and nonrespiratory causes of hypoxemia should be considered. For patients who remain hypoxemic after PEEP optimization, neuromuscular blockade and prone positioning should be considered. Profound refractory hypoxemia (Pao₂/Fio₂ < 80 mm Hg) after PEEP titration is an indication to consider extracorporeal life support. This may necessitate early transfer to a center with expertise in these techniques. Inhaled vasodilators and nontraditional ventilator modes may improve oxygenation, but evidence for improved outcomes is weak.