A Retrospective Cohort Analysis of Analgosedation Requirements in COVID-19 Compared to Non-COVID-19 Extracorporeal Membrane Oxygenation Patients

BACKGROUND

Reports have described increased sedation requirements in patients with acute respiratory distress syndrome (ARDS) while on extracorporeal membrane oxygenation (ECMO) and for intubated COVID-19 patients. Thus, the objective of this study was to assess the analgosedation requirements of COVID-19 patients receiving ECMO compared to non-COVID-19 ECMO patients.

METHODS

This retrospective, observational cohort study included adult patients with ARDS requiring venovenous or venopulmonary arterial ECMO admitted to a single intensive care unit from January 2017 to December 2021. Patients were categorized as COVID-19 ECMO or non-COVID-19 ECMO. The primary outcome was median daily dosing of parenteral analgosedative medications. Pertinent secondary outcomes included incidence of extubation or tracheostomy and change in sedation following tracheostomy or addition of oral agents.

RESULTS

A total of 109 patients were evaluated; 63 COVID-19 ECMO patients and 46 non-COVID ECMO patients. The primary outcome was statistically higher in the COVID-19 compared to non-COVID-19 patients for propofol (4131.0 mg vs 2704.8 mg, P < .001), dexmedetomidine (1581.4 mcg vs 1081.3 mcg, P  =  .016), and parenteral morphine equivalents ([PME], 209.3 mg vs 154.1 mg, P  =  .027), but only propofol remained significant after adjustment for weight (31.1 mcg/kg/day vs 37.7 mcg/kg/day, P  =  .014). COVID-19 was significantly associated with increased propofol and PME requirements after adjustment for confounders on linear regression analysis. COVID-19 patients had more days with non-zero dose for propofol (8 days vs 7 days), dexmedetomidine (13 days vs 8.5 days), and PME (17 days vs 8.5 days). The only interventions that were associated with reductions in propofol dose were tracheostomy and antipsychotics.

CONCLUSIONS

COVID-19 patients on ECMO had significantly longer durations and higher doses of propofol, dexmedetomidine, and parenteral opioids over the first 28 days of cannulation. The only interventions that were associated with statistical reductions in propofol were antipsychotics and tracheostomy.

Practices surrounding antimicrobial use in patients managed with extracorporeal membrane oxygenation: An international survey

PURPOSE

This study aimed to survey critical care clinicians and characterize their perception of antimicrobial dosing strategies in patients receiving extracorporeal membrane oxygenation (ECMO).

METHODS

International, cross-sectional survey distributed to members of the Society of Critical Care Medicine in October 2022.

RESULTS

Respondents were primarily physicians (45%), with 92% practicing in North America. Ninety-seven percent of respondents reported antimicrobial dosing in critically ill patients to be challenging, due to physiological derangements seen in the patient population. Eighty-seven percent reported consideration of physicochemical drug properties when dosing antimicrobials in ECMO-supported patients, with lipophilicity (83%) and degree of protein binding (74%) being the two most common. Respondents' approach to antimicrobial dosing strategies did not significantly differ in critically ill ECMO-supported patients, compared to patients with equal severity of illness not receiving ECMO support.

CONCLUSION

Approaches to antimicrobial dosing strategies do not significantly differ among respondents between critically ill patients on ECMO support, compared to patients with equal severity of illness not receiving ECMO support. These findings were unexpected considering the added physiologic complexity of the ECMO circuit to critically ill adult patients and the need for well designed and adequately powered studies to inform empiric dosing guidance for ECMO-supported patients.

The Influence of Extracorporeal Membrane Oxygenation on Antibiotic Pharmacokinetics

Extracorporeal membrane oxygenation (ECMO) is becoming increasingly utilized to support critically ill patients who experience life-threatening cardiac or pulmonary compromise. The provision of this intervention poses challenges related to its complications and the optimization of medication therapy. ECMO's mechanical circulatory support is facilitated via various devices and equipment that have been shown to sequester lipophilic- and protein-bound medications, including anti-infectives. Since infectious outcomes are dependent on achieving specific anti-infectives' pharmacodynamic targets, the understanding of these medications' pharmacokinetic parameters in the setting of ECMO is important to clinicians. This narrative, non-systematic review evaluated the findings of the most recent and robust pharmacokinetic analyses for commonly utilized anti-infectives in the setting of ECMO. The data from available literature indicates that anti-infective pharmacokinetic parameters are similar to those observed in other non-ECMO critically ill populations, but considerable variability in the findings was observed between patients, thus prompting further evaluation of therapeutic drug monitoring in this complex population.

Knowledge gaps and research priorities in adult veno-arterial extracorporeal membrane oxygenation: a scoping review

PURPOSE

This scoping review aims to identify and describe knowledge gaps and research priorities in veno-arterial extracorporeal membrane oxygenation (VA-ECMO).

METHODS

An expert panel was recruited consisting of eight international experts from different backgrounds. First, a list of priority topics was made. Second, the panel developed structured questions using population, intervention, comparison and outcomes (PICO) format. All PICOs were scored and prioritized. For every selected PICO, a structured literature search was performed.

RESULTS

After an initial list of 49 topics, eight were scored as high-priority. For most of these selected topics, current literature is limited to observational studies, mainly consisting of retrospective cohorts. Only for ECPR and anticoagulation, randomized controlled trials (RCTs) have been performed or are ongoing. Per topic, a summary of the literature is stated including recommendations for further research.

CONCLUSIONS

This scoping review identifies and presents an overview of knowledge gaps and research priorities in VA-ECMO. Current literature is mostly limited to observational studies, although with increasing attention for this patient population, more RCTs are finishing or ongoing. Translational research, from preclinical trials to high-quality or randomized controlled trials, is important to improve the standard practices in this critically ill patient population. Take-home message This scoping review identifies and presents an overview of research gaps and priorities in VA-ECMO. Translational research, from preclinical trials to high-quality or randomized controlled trials, is important to improve the standard practices in this critically ill patient population.

Neuroprognostication Under ECMO After Cardiac Arrest: Are Classical Tools Still Performant?

BACKGROUND

According to international guidelines, neuroprognostication in comatose patients after cardiac arrest (CA) is performed using a multimodal approach. However, patients undergoing extracorporeal membrane oxygenation (ECMO) may have longer pharmacological sedation and show alteration in biological markers, potentially challenging prognostication. Here, we aimed to assess whether routinely used predictors of poor neurological outcome also exert an acceptable performance in patients undergoing ECMO after CA.

METHODS

This observational retrospective study of our registry includes consecutive comatose adults after CA. Patients deceased within 36 h and not undergoing prognostic tests were excluded. Veno-arterial ECMO was initiated in patients < 80 years old presenting a refractory CA, with a no flow < 5 min and a low flow ≤ 60 min on admission. Neuroprognostication test performance (including pupillary reflex, electroencephalogram, somatosensory-evoked potentials, neuron-specific enolase) toward mortality and poor functional outcome (Cerebral Performance Categories [CPC] score 3-5) was compared between patients undergoing ECMO and those without ECMO.

RESULTS

We analyzed 397 patients without ECMO and 50 undergoing ECMO. The median age was 65 (interquartile range 54-74), and 69.8% of patients were men. Most had a cardiac etiology (67.6%); 52% of the patients had a shockable rhythm, and the median time to return of an effective circulation was 20 (interquartile range 10-28) minutes. Compared with those without ECMO, patients receiving ECMO had worse functional outcome (74% with CPC scores 3-5 vs. 59%, p = 0.040) and a nonsignificant higher mortality (60% vs. 47%, p = 0.080). Apart from the neuron-specific enolase level (higher in patients with ECMO, p < 0.001), the presence of prognostic items (pupillary reflex, electroencephalogram background and reactivity, somatosensory-evoked potentials, and myoclonus) related to unfavorable outcome (CPC score 3-5) in both groups was similar, as was the prevalence of at least any two such items concomitantly. The specificity of each these variables toward poor outcome was between 92 and 100% in both groups, and of the combination of at least two items, it was 99.3% in patients without ECMO and 100% in those with ECMO. The predictive performance (receiver operating characteristic curve) of their combination toward poor outcome was 0.822 (patients without ECMO) and 0.681 (patients with ECMO) (p = 0.134).

CONCLUSIONS

Pending a prospective assessment on a larger cohort, in comatose patients after CA, the performance of prognostic factors seems comparable in patients with ECMO and those without ECMO. In particular, the combination of at least two poor outcome criteria appears valid across these two groups.

Impact of CytoSorb Hemoadsorption on Sedation Requirements in Patients With Severe COVID-19 on Venovenous Extracorporeal Membrane Oxygenation

Hemoadsorption with CytoSorb has been used as an adjunct in the treatment of severe coronavirus disease 2019 (COVID-19)-related respiratory failure. It remains unknown if CytoSorb hemoadsorption will alter sedative and analgesic dosing in critically ill patients on venovenous extracorporeal membrane oxygenation (VV-ECMO). We conducted a retrospective review of patients with severe COVID-19 requiring VV-ECMO for respiratory support. Patients who were enrolled in a clinical study of CytoSorb were compared with patients on VV-ECMO alone. Data were collected for the 72-hour CytoSorb therapy and an additional 72 hours post-CytoSorb, or a corresponding control time period. Sedative and analgesic doses were totaled for each day and converted to midazolam or fentanyl equivalents, respectively. The primary endpoint, change in sedative and analgesic requirements over time, were compared using a two-way mixed analysis of variance. Of the 30 patients cannulated for VV-ECMO for COVID-19, 4 were excluded, leaving 8 patients in the CytoSorb arm and 18 in the Control. There was no effect of CytoSorb therapy on midazolam equivalents over the 72-hour therapy (p = 0.71) or the 72 hours post-CytoSorb (p = 0.11). In contrast, there was a significant effect of CytoSorb therapy on fentanyl equivalents over the first 72 hours (p = 0.01), but this was not consistent over the 72-hours post-CytoSorb (p = 0.23). CytoSorb therapy led to significant increases in analgesic requirements without impacting sedative requirements. Further research is needed to define the relevance of CytoSorb hemoadsorption on critical care pharmacotherapy.

ECLS-associated infections in adults: what we know and what we don't yet know

Extracorporeal life support (ECLS) is increasingly used in the management of patients with severe cardiopulmonary disease. Infections are frequently the etiologies underlying the respiratory, and occasionally cardiac, failure that necessitates ECLS. Just as importantly, infections are among the most commonly reported adverse events during ECLS. Infections in this setting may be the sequelae of prolonged critical illness or of underlying immune dysregulation; they may be hospital-acquired infections, and they may or may not be attributable to the presence of ECLS itself, the latter being an aspect that can be difficult to determine. Current registry data and evidence from the literature offer some insights, but also leave open many questions regarding the nature and significance of infections reported both before and during ECLS, including the question of any causal link between ECLS and the development of infections. An ongoing lack of consistency in the identification, diagnosis, management, and prevention of infections during ECLS is limiting our ability to interpret literature data and thus highlighting the need for more rigorous investigation and standardization of definitions. This review aims to characterize the current understanding of infections associated with the use of ECLS, taking into account data from the updated Extracorporeal Life Support Organization Registry, which provides important context for understanding the epidemiology and outcomes of these patients.