High-Dose Sedation and Analgesia During Extracorporeal Membrane Oxygenation: A Focus on the Adjunctive Use of Ketamine

Ketamine infusion for sedation in a patient on extracorporeal membrane oxygenation (ECMO)

Introduction: we sought to explore the efficacy of ketamine in a patient on extracorporeal membrane oxygenation (ECMO) receiving ketamine for sedation by investigating the utility of plasma ketamine concentrations.Case report: retrospective chart review of one critically ill patient on ECMODiscussion: This was a descriptive review of serial plasma ketamine concentrations in an ECMO patient. Although no reference plasma concentrations exist in ECMO patients, ketamine levels appeared to be lower than those seen in surgical patients not on ECMO.Conclusion: At this point, no reference plasma concentrations exist for ketamine in ECMO patients, further research may help understand the effects of ECMO on ketamine disposition and that lower ketamine concentrations may be used for effective analgesia or sedation.

Analgosedation in Critically Ill Adults Receiving Extracorporeal Membrane Oxygenation Support

Extracorporeal membrane oxygenation (ECMO) is an increasingly utilized intervention for cardiopulmonary failure. Analgosedation during ECMO support is essential to ensure adequate pain and agitation control and ventilator synchrony, optimize ECMO support, facilitate patient assessment, and minimize adverse events. Although the principles of analgosedation are likely similar for all critically ill patients, ECMO circuitry alters medication pharmacodynamics and pharmacokinetics. The lack of clinical guidelines for analgosedation during ECMO, especially at times of medication shortage, can affect patient management. Here, we review pharmacological considerations, protocols, and special considerations for analgosedation in critically ill adults receiving ECMO support.

A Narrative Review of the Impact of Extracorporeal Membrane Oxygenation on the Pharmacokinetics and Pharmacodynamics of Critical Care Therapies

Objective:

Extracorporeal membrane oxygenation (ECMO) utilization is increasing on a global scale, and despite technological advances, minimal standardized approaches to pharmacotherapeutic management exist. This objective was to create a comprehensive review for medication dosing in ECMO based on the most current evidence.

Data Sources:

A literature search of PubMed was performed for all pertinent articles prior to 2022. The following search terms were utilized: ECMO, pharmacokinetics, pharmacodynamics, sedation, analgesia, antiepileptic, anticoagulation, antimicrobial, antifungal, nutrition. Retrospective cohort studies, case-control studies, case series, case reports, and ex vivo investigations were reviewed.

Study Selection and Data Extraction:

PubMed (1975 through July 2022) was the database used in the literature search. Non-English studies were excluded. Search terms included both drug class categories, specific drug names, ECMO, and pharmacokinetics.

Data Synthesis:

Medications with high protein binding (>70%) and high lipophilicity (logP > 2) are associated with circuit sequestration and the potential need for dose adjustment. Volume of distribution changes with ECMO may also impact dosing requirements of common critical care medications. Lighter sedation targets and analgosedation may help reduce sedative and analgesia requirements, whereas higher antiepileptic dosing is recommended. Vancomycin is minimally affected by the ECMO circuit and recommendations for dosing in critically ill adults are reasonable. Anticoagulation remains challenging as optimal aPTT goals have not been established.

Relevance to Patient Care and Clinical Practice:

This review describes the anticipated impacts of ECMO circuitry on sedatives, analgesics, anticoagulation, antiepileptics, antimicrobials, antifungals, and nutrition support and provides recommendations for drug therapy management.

Conclusions:

Medication pharmacokinetic/pharmacodynamic parameters should be considered when determining the potential impact of the ECMO circuit on attainment of therapeutic effect and target serum drug concentrations, and should guide therapy choices and/or dose adjustments when data are not available.

Management of procedural pain in the intensive care unit

Pain is a common experience for inpatients, and intensive care unit (ICU) patients undergo more pain than other departmental patients, with an incidence of 50% at rest and up to 80% during common care procedures. At present, the management of persistent pain in ICU patients has attracted considerable attention, and there are many related clinical studies and guidelines. However, the management of transient pain caused by certain ICU procedures has not received sufficient attention. We reviewed the different management strategies for procedural pain in the ICU and reached a conclusion. Pain management is a process of continuous quality improvement that requires multidisciplinary team cooperation, pain-related training of all relevant personnel, effective relief of all kinds of pain, and improvement of patients' quality of life. In clinical work, which involves complex and diverse patients, we should pay attention to the following points for procedural pain: (1) Consider not only the patient's persistent pain but also his or her procedural pain; (2) Conduct multimodal pain management; (3) Provide combined sedation on the basis of pain management; and (4) Perform individualized pain management. Until now, the pain management of procedural pain in the ICU has not attracted extensive attention. Therefore, we expect additional studies to solve the existing problems of procedural pain management in the ICU.

Clinical outcomes associated with sedation and analgesia in patients supported with venoarterial extracorporeal membrane oxygenation

Sedatives and analgesics are frequently used in critically ill adult patients requiring mechanical ventilation in the intensive care unit, but optimal agent selection and dosing in patients supported with venoarterial extracorporeal membrane oxygenation remain poorly defined. This retrospective study evaluated whether sedative and analgesic agent selection and dosing had any impact on clinical outcomes after venoarterial extracorporeal membrane oxygenation decannulation. The primary endpoint of our study was the incidence of delirium within 48 h after venoarterial extracorporeal membrane oxygenation decannulation in patients who received an empiric ⩾50% sedation reduction of benzodiazepines (N = 22, group 2) compared to those who did not (N = 10, group 1) and those who required no sedatives within 24 h prior to venoarterial extracorporeal membrane oxygenation decannulation (N = 21, group 3). Secondary endpoints included time to extubation after decannulation, need for tracheostomy after decannulation, intensive care unit length of stay after decannulation, total hospital length of stay, and in-hospital mortality. Delirium within 48 h after decannulation was observed in 47% of all patients and did not differ between the three groups (50% vs 50% vs 43%, p = 0.9). No differences were observed in the secondary endpoints; though there was a trend toward shorter duration of mechanical ventilation and intensive care unit length of stay in patients who received an empiric ⩾50% sedation reduction. Our study suggests that we may need more than a 50% reduction in sedation but prospective studies with a larger sample size are warranted to evaluate how sedative/analgesic selection and dosing affect important clinical outcomes.

Delayed Onset of Central Diabetes Insipidus With Ketamine Sedation: A Report of 2 Cases

Ketamine is being prescribed with greater frequency due to an emphasis on multimodal analgesia. With increasing use, uncommon adverse effects associated with ketamine are likely to surface. Limited reports of transient central diabetes insipidus (DI) occurring early after initiation (ie, within 10 hours) of ketamine have been reported. We present 2 cases of delayed onset (32 hours or more after initiation), ketamine-induced, transient central DI in patients cannulated for venovenous extracorporeal membranous oxygenation. No other causes of central DI were determined based upon physical examination or laboratory data, and both patients responded to treatment with desmopressin/vasopressin. The Naranjo adverse drug reaction probability scale noted a probable causation for each case. These cases demonstrate the possibility of a rare but serious complication of ketamine. Improvement after discontinuation of ketamine and administration of desmopressin/vasopressin appear to support a drug-effect association.

Perspectives on adjunctive use of ketamine for analgosedation during extracorporeal membrane oxygenation

Analgosedation on ECMO is more than the choice of any drug, it has to be context specific. Ketamine may be considered as an adjunctive therapy in patients requiring high-dose opioids and sedatives during ECMO support with difficulty to achieve a target RASS. Considering ketamine provides analgesia while maintaining airway reflexes, it could be useful for early ECMO weaning and use of ECMO in awake, non-intubated, spontaneously breathing patients with respiratory failure ('awake' ECMO), especially for patients having considerable waiting periods while being bridged to transplant. The hemodynamic effects of ketamine may provide the benefit of decreasing vasopressor requirements, thereby potentially improving microcirculation. In this context, the effects on end-organ function and the need for renal replacement therapy should be investigated. Pharmacokinetic and pharmacodynamic studies on ketamine ex- and in vivo are of utmost importance to delineate its pharmacological profile and effectiveness during ECMO therapy and to create admissible future study hypothesis.

Perioperative Management of the Adult Patient on Venovenous Extracorporeal Membrane Oxygenation Requiring Noncardiac Surgery

The use of venovenous extracorporeal membrane oxygenation is increasing worldwide. These patients often require noncardiac surgery. In the perioperative period, preoperative assessment, patient transport, choice of anesthetic type, drug dosing, patient monitoring, and intraoperative and postoperative management of common patient problems will be impacted. Furthermore, common monitoring techniques will have unique limitations. Importantly, patients on venovenous extracorporeal membrane oxygenation remain subject to hypoxemia, hypercarbia, and acidemia in the perioperative setting despite extracorporeal support. Treatments of these conditions often require both manipulation of extracorporeal membrane oxygenation settings and physiologic interventions. Perioperative management of anticoagulation, as well as thresholds to transfuse blood products, remain highly controversial and must take into account the specific procedure, extracorporeal membrane oxygenation circuit function, and patient comorbidities. We will review the physiologic management of the patient requiring surgery while on venovenous extracorporeal membrane oxygenation.

Medicating patients during extracorporeal membrane oxygenation: the evidence is building

This article is one of ten reviews selected from the Annual Update in Intensive Care and Emergency Medicine 2017. Other selected articles can be found online at http://ccforum.com/series/annualupdate2017 . Further information about the Annual Update in Intensive Care and Emergency Medicine is available from http://www.springer.com/series/8901 .