"Awake" Extracorporeal Membrane Oxygenation Combined With Continuous Renal Replacement Therapy For the Treatment of Severe Chemical Gas Inhalation Lung Injury

Sedation management and processed EEG-based solutions during venovenous extracorporeal membrane oxygenation: a narrative review of key challenges and potential benefits

Extracorporeal membrane oxygenation (ECMO) is an established technique for managing severe cardiorespiratory failure. However, it is invasive and requires profound analgo-sedation during initiation and often throughout the therapy. Managing sedation in venovenous (VV) ECMO patients is particularly challenging due to the impact of ECMO circuits on pharmacokinetics and specific patient requirements. This can lead to unpredictable sedative effects and require multiple drugs at higher doses. Additionally, sedation is usually managed with traditional scoring methods, which are subjective and invalid during neuromuscular blockade. These uncertainties may impact outcomes. Recent clinical practice increasingly focuses on reducing sedation to enable earlier physiotherapy and mobilisation, particularly in patients awaiting transplants or receiving mechanical circulatory support. In this context, processed electroencephalogram-based (pEEG) sedation monitoring might be promising, having shown benefits in general anaesthesia and intensive care. However, the technology has limitations, and its benefits in ECMO practice have yet to be formally evaluated. This review provides insights into the challenges of ECMO sedation, including pharmacokinetics, unique ECMO requirements, and the implications of inadequate sedation scores. Finally, it includes a brief overview of the practicality and limitations of pEEG monitoring during VV-ECMO, highlighting a significant research gap.

Extracorporeal Membrane Oxygenation Without Invasive Ventilation for Respiratory Failure in Adults: A Systematic Review

OBJECTIVES

Extracorporeal membrane oxygenation (ECMO) is an advanced treatment for acute severe respiratory failure. Patients on ECMO are frequently maintained sedated and immobilized until weaning from ECMO, first, and then from mechanical ventilation. Avoidance of sedation and invasive ventilation during ECMO may have potential advantages. We performed a systematic literature review to assess efficacy and safety of awake ECMO without invasive ventilation in patients with respiratory failure.

DATA SOURCES

PubMed, Web of Science, and Scopus were searched for studies reporting outcome of awake ECMO for adult patients with respiratory failure.

STUDY SELECTION

We included all studies reporting outcome of awake ECMO in patients with respiratory failure. Studies on ECMO for cardiovascular failure, cardiac arrest, or perioperative support and studies on pediatric patients were excluded. Two investigators independently screened and selected studies for inclusion.

DATA EXTRACTION

Two investigators abstracted data on study characteristics, rate of awake ECMO failure, and mortality. Primary outcome was rate of awake ECMO failure (need for intubation). Pooled estimates with corresponding 95% CIs were calculated. Subgroup analyses by setting were performed.

DATA SYNTHESIS

A total of 57 studies (28 case reports) included data from 467 awake ECMO patients. The subgroup of patients with acute respiratory distress syndrome showed a pooled estimate for awake ECMO failure of 39.3% (95% CI, 24.0-54.7%), while in patients bridged to lung transplantation, pooled estimate was 23.4% (95% CI, 13.3-33.5%). Longest follow-up mortality was 121 of 439 (pooled estimate, 28%; 95% CI, 22.3-33.6%). Mortality in patients who failed awake ECMO strategy was 43 of 74 (pooled estimate, 57.2%; 95% CI, 40.2-74.3%). Two cases of cannula self-removal were reported.

CONCLUSIONS

Awake ECMO is feasible in selected patients, although the effect on outcome remains to be demonstrated. Mortality is almost 60% in patients who failed awake ECMO strategy.

Kidney involvement in coronavirus-associated diseases (Review)

Since 2003, coronaviruses have caused multiple global pandemic diseases, including severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS) and coronavirus disease 2019 (COVID-19). Clinical and autopsy findings suggest that the occurrence of kidney injury during infection may negatively affect the clinical outcomes of infected patients. The authoritative model predicts that outbreaks of other novel coronavirus pneumonias will continue to threaten human health in the future. The aim of the present systematic review was to summarize the basic knowledge of coronavirus, coronavirus infection-associated kidney injury and the corresponding therapies, in order to provide new insights for clinicians to better understand the kidney involvement of coronavirus so that more effective therapeutic strategies can be employed against coronavirus infection in the future.

Effect of CRRT combined with low-flow ECMO on canines with ARDS and hypercapnia

To observe the effect of continuous renal replacement therapy (CRRT) combined with low-flow extracorporeal membrane oxygenation (ECMO) of V-V mode on anti-inflammation, improving oxygenation and reducing P_aCO₂ in canines with acute respiratory distress syndrome (ARDS) and hypercapnia. A total of 30 healthy adult canines were randomly divided into sham group (n = 10), ECMO (EC) group (n = 10) and CRRT + ECMO (CR + EC) group (n = 10). Sham group was only treated with invasive mechanical ventilation. EC group was also treated with ECMO. CR + EC group was treated with CRRT combined with low-flow ECMO of V-V mode besides invasive mechanical ventilation. The results showed that hazard ratio was lower in the CR + EC group. Inflammatory factors, OI values, and PaCO₂ levels were lower in the CR + EC group. There was no significant difference in the levels of MAP, CO and T among the three groups. No significant complications or death was developed in the three groups. Compared with ECMO group at T3, T6 and T9, IL-6 [(276.13 ± 8.32, 262.04 ± 7.15, 259.33 ± 7.31)ng/L VS (352.67 ± 19.24, 360.24 ± 23.58, 362.21 ± 25.24)ng/L] and TNF-α [(50.14 ± 1.75, 50.45 ± 1.81, 48.03 ± 1.24) ng/L VS (70.25 ± 3.02, 72.45 ± 3.25, 76.69 ± 2.18)ng/L] in CR + EC group were decreased (P < 0.0001). Compared with sham group, IL-6 [(343.76 ± 21.97, 345.91 ± 19.89, 340.34 ± 22.17)ng/L]and TNF-α [(68.10 ± 2.96, 67.31 ± 3.01, 70.34 ± 3.35)ng/L] of T3, T6 and T9 in CR + EC group were lower (P < 0.0001). These findings indicated that CRRT combined with low-flow ECMO of V-V mode had a positive effect on anti-inflammation, oxygenation improvement and surplus blood CO₂ removal in canines with ARDS and hypercapnia. These results provide a promising treatment regimen for ARDS.