Invited Presidential Lecture: Critical Care Psychiatry: Unique Challenges in the Management of Sleep, Pain & Delirium During ECMO Treatment

Extracorporeal membrane oxygenation (ECMO) therapy has been around since the 1970s and has completely changed how critical care physicians view supportive therapy for certain patients. ECMO therapy is a supportive therapy provided by a mechanical extracorporeal circuit that is able to directly oxygenate and remove carbon dioxide from the blood. By performing this, ECMO can provide cardiac, respiratory, or combined cardiopulmonary supportive therapy in cases of failure. ECMO therapy also places less emphasis on invasive mechanical ventilation, which prevents barotrauma and gives rest to the lungs. Therefore, they are used for several different conditions, which more recently have included the management of an increasing number of cases of COVID-19 induced pneumonia. Despite its numerous advantages, the use of ECMO carries the risk of multiple complications. These include bleeding (30-50%), thromboembolism (up to 16%), and neurologic injury (up to 10%), including anoxic brain injury, coma, stroke and encephalopathy/delirium (Bartlett 2021). While delirium prevention and mitigation strategies exist for critical care patients (Maldonado 2008, Barr, Fraser et al. 2013, Maldonado 2017), they must be modified in the management of patients on ECMO and prioritizes proactive management of hyperactive and mixed delirium states. ECMO further complicates the situation by altering the pharmacokinetics and pharmacodynamics of analgesics and sedatives, including an increase in the circulating volume of blood, altered renal and hepatic blood flow, effects of flow rates and drug–circuit interactions (Dagan, Klein et al. 1994, Shekar, Fraser et al. 2012, Shekar, Roberts et al. 2012, Dzierba, Abrams et al. 2017, Cheng, Abdul-Aziz et al. 2018). Chief among these changes is the problem of drug sequestration within the ECMO circuit. The polyvinyl chloride (PVC) tubing and membrane oxygenator (MO) used in ECMO have both been shown to add a large volume for distribution of drugs, as well as a large surface area for adsorption of drugs onto a foreign surface (i.e., sequester drug) within the ECMO circuit (Bhatt-Meht and Annich 2005, Preston, Hodge et al. 2007). Specifically, a given substances lipophilicity and protein binding properties with determine the risk of sequestration, which might dramatically affect the amount of drug received by the patient, further affecting clinical effectiveness, which will in turn determine the clinician’s success in safely managing hypnosis, pain and delirium among patients requiring ECMO treatment.

NOTE: THERE IS NO Q&A FOLLOWING THIS PRESENTATION