Ketamine infusion for patients receiving extracorporeal membrane oxygenation support: a case series

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.

Neurocritical Care of Mechanical Circulatory Support Devices

PURPOSE OF REVIEW

Mechanical circulatory support (MCS) devices have demonstrated improved survival outcomes in otherwise refractory cardiopulmonary failure but are associated with significant neurologic morbidity and mortality. This review aims to characterize MCS-associated brain injury and discuss the neurocritical care of this population.

RECENT FINDINGS

We found no practice guidelines or specific management strategies for the neurocritical care of patients with MCS devices. Acute brain injury was commonly observed in short-term and durable MCS devices. There is emerging evidence that a standardized neurological monitoring and management algorithm for MCS device-associated brain injury is feasible and potentially improves neurological outcomes. While MCS devices are associated with significant neurologic morbidity and mortality, there is scant evidence regarding optimal neuromonitoring and neurocritical care. With the increase in use of MCS devices for both short-term and durable applications, improved outcomes will depend on early identification and intervention of neurologic complications and further research into their pathophysiology.

Reducing Opioid Use in Patients Undergoing Cardiac Surgery - Preoperative, Intraoperative, and Critical Care Strategies

Patients undergoing cardiothoracic surgery are exposed to opioids in the operating room and intensive care unit and after hospital discharge. Opportunities exist to reduce perioperative opioid use at all stages of care and include alternative oral and intravenous medications, novel intraoperative regional anesthetic techniques, and postoperative opioid-sparing sedative and analgesic strategies. In this review, currently used and investigational strategies to reduce the opioid burden for cardiothoracic surgical patients are explored.

Simultaneous quantitative LC-MS method of ketamine, midazolam and their metabolites (dehydronorketamine, norketamine and 1hydroxymidazolam) for its application in patients on extracorporeal membrane oxygenation (ECMO) therapy

Ketamine (Ket) and midazolam (MDZ) are commonly administered drugs in the intensive care setting for analgesia and sedation. Ket and MDZ are metabolized to dehydro-norketamine (DHNK), nor-ketamine (NK) and 1-hydroxy midazolam (1HMDZ). Limited studies evaluating their pharmacokinetics exists in patients on extracorporeal membrane oxygenation (ECMO) therapy. Therefore, we developed a quantitative, high-performance liquid chromatography-mass spectrometry (with single ion monitoring) method to simultaneously detect Ket, MDZ and their (DHNK, NK and 1HMDZ) metabolites in human plasma. Considerable sensitivity was obtained for the analytes using a C₁₈ HILIC column operated by a high-performance liquid chromatography system coupled with a Thermo Exactive Orbitrap mass spectrometer. Calibration curves were developed for analyte molecules (n = 5) in the presence of carbamazepine (CBZ) as an internal standard. The lower limits of quantitation (LLOQ) for Ket and MDZ were 20 and 10 ng/mL, respectively with the LLOQ for DHNK, NK and 1HMDZ at 470, 320 and 150 ng/ml. Moreover, the percent coefficient of variance and precision for inter- and intra-day runs were within the standards set forth by the ICH and FDA guidelines. This method is sensitive and has been successfully applied to an ongoing pharmacokinetic study in patients on ECMO therapy.

Overview of Pharmacological Considerations in Extracorporeal Membrane Oxygenation

Extracorporeal membrane oxygenation has become more widely used in recent years. Although this technology has proven to be lifesaving, it is not devoid of complications contributing to significant morbidity and mortality. Nurses who care for patients receiving extracorporeal membrane oxygenation should further their understanding of changes in medication profiles due to complex interactions with the extracorporeal membrane oxygenation circuitry. The aim of this comprehensive review is to give nurses a better understanding of analgesic, sedative, anti-infective, and anticoagulation medications that are frequently used to treat patients receiving extracorporeal membrane oxygenation.

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.

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.

Sedation Practice in Extracorporeal Membrane Oxygenation-Treated Patients with Acute Respiratory Distress Syndrome: A Retrospective Study

Our objective was to characterize sedation management in adult patients with severe respiratory distress syndrome (ARDS) treated with venovenous extracorporeal membrane oxygenation (VV-ECMO). We conducted a retrospective chart review of these patients treated at Toronto General Hospital between January 2012 and October 2015. Medications administered (sedative, analgesic, paralytic, and antipsychotic), sedation depth (Sedation Agitation Scale [SAS] score) delirium assessments, and mobilization were recorded daily. Forty-five adults (33 males, median age 47 years; interquartile range [IQR], 35-56]) with ARDS (median PaO2/FiO2 71; IQR 59-83) because of respiratory infection (91%) were treated with VV-ECMO for a median of 11 days (IQR, 7-17). After ECMO initiation, 96% patients were deeply sedated (SAS score < 3) with continuous infusions of midazolam (49%), propofol (18%), or both (29%) and 98% were receiving opioid infusions (93% fentanyl). Patients were deeply sedated for a median of 6 days (IQR, 3-10) after cannulation before transitioning to intermediate or light sedation (SAS score ≥ 3). Before ECMO discontinuation, 77% of surviving patients were intermediately or lightly sedated, 20% were receiving no sedatives, and 9% were receiving no opioids. During ECMO, 58% had positive delirium assessment and 24% experienced agitation (SAS ≥ 6). During ECMO support, 71% received physical therapy that occurred after a median of 7 days (IQR, 4-12) after cannulation. In conclusion, we found that although patients were deeply sedated for a prolonged duration after VV-ECMO initiation, many were able to safely achieve light sedation and active mobilization.

Role of Methadone in Extracorporeal Membrane Oxygenation: Two Case Reports

Extracorporeal membrane oxygenation (ECMO) affects pharmacokinetics/dynamics of drugs in unpredictable ways. Anecdotally, ECMO patients require high doses of opioids and sedatives, leading to concerns of tolerance. Methadone is a long-acting synthetic opioid with antagonist properties at the n-methyl-d-aspartate (NMDA) receptor. It has been shown to improve spontaneous breathing trials and weaning from mechanical ventilation; however, there is no literature describing its use in ECMO. We describe two patients from the cardiac surgery intensive care unit at Cedars Sinai (Los Angeles, CA) on ECMO for over 30 days maintained on methadone.

Medication Complications in Extracorporeal Membrane Oxygenation

The need for extracorporeal membrane oxygenation (ECMO) therapy is a marker of disease severity for which multiple medications are required. The therapy causes physiologic changes that impact drug pharmacokinetics. These changes can lead to exposure-driven decreases in efficacy or increased incidence of side effects. The pharmacokinetic changes are drug specific and largely undefined for most drugs. We review available drug dosing data and provide guidance for use in the ECMO patient population.

Sedation and Mobilization During Venovenous Extracorporeal Membrane Oxygenation for Acute Respiratory Failure: An International Survey

OBJECTIVES

To characterize sedation, analgesia, delirium, and mobilization practices in patients supported with venovenous extracorporeal membrane oxygenation for severe acute respiratory failure.

DESIGN

Cross-sectional electronic survey administered January 2016 to March 2016.

SETTING

Three-hundred ninety-four extracorporeal membrane oxygenation centers registered with the Extracorporeal Life Support Organization.

SUBJECTS

Extracorporeal membrane oxygenation medical directors and program coordinators.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

We analyzed responses from 209 respondents (53%), mostly from academic centers (63%); 41% respondents provide venovenous extracorporeal membrane oxygenation to adults exclusively. Following venovenous extracorporeal membrane oxygenation initiation, 97% respondents administer sedative/analgesic infusions, and the sedation target was "sedated" or "very sedated" for 59%, "calm and cooperative" for 25%, and "unarousable" for 16%. Use of daily sedation interruption and a sedation/analgesia protocol was reported by 51% and 39%, respectively. Midazolam (48%) and propofol (19%) were reported as the most frequently used sedatives; fentanyl (44%) and morphine (20%) the most frequent opioids. Use of a delirium scale was reported by 55% respondents. Physical therapy was reported by 84% respondents, with 41% initiating it within 72 hours after cannulation. Mobilization goals varied from range of motion exercises (81%) to ambulation (22%). The most frequently perceived barriers to mobilization were hemodynamic instability, hypoxemia, and dependency on venovenous extracorporeal membrane oxygenation support.

CONCLUSIONS

The majority of respondents reported targeting moderate to deep sedation following cannulation, with the use of sedative and opioid infusions. There is considerable variability surrounding early physical therapy and mobilization goals for patients with acute respiratory failure supported by 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 .

Adult venovenous extracorporeal membrane oxygenation for severe respiratory failure: Current status and future perspectives

Extracorporeal membrane oxygenation (ECMO) for severe acute respiratory failure was proposed more than 40 years ago. Despite the publication of the ARDSNet study and adoption of lung protective ventilation, the mortality for acute respiratory failure due to acute respiratory distress syndrome has continued to remain high. This technology has evolved over the past couple of decades and has been noted to be safe and successful, especially during the worldwide H1N1 influenza pandemic with good survival rates. The primary indications for ECMO in acute respiratory failure include severe refractory hypoxemic and hypercarbic respiratory failure in spite of maximum lung protective ventilatory support. Various triage criteria have been described and published. Contraindications exist when application of ECMO may be futile or technically impossible. Knowledge and appreciation of the circuit, cannulae, and the physiology of gas exchange with ECMO are necessary to ensure lung rest, efficiency of oxygenation, and ventilation as well as troubleshooting problems. Anticoagulation is a major concern with ECMO, and the evidence is evolving with respect to diagnostic testing and use of anticoagulants. Clinical management of the patient includes comprehensive critical care addressing sedation and neurologic issues, ensuring lung recruitment, diuresis, early enteral nutrition, treatment and surveillance of infections, and multisystem organ support. Newer technology that delinks oxygenation and ventilation by extracorporeal carbon dioxide removal may lead to ultra-lung protective ventilation, avoidance of endotracheal intubation in some situations, and ambulatory therapies as a bridge to lung transplantation. Risks, complications, and long-term outcomes and resources need to be considered and weighed in before widespread application. Ethical challenges are a reality and a multidisciplinary approach that should be adopted for every case in consideration.