KetAmine and Recovery After Mechanical VentilAtion ( KARMA ) (KARMA)

Intensive Care Treatment With Adjuvant KetAmine and Recovery After Mechanical ventilAtion: a Multicenter Doubleblind Randomized Controlled Trial.

Invasive mechanical ventilation of critically ill patients in the intensive care unit (ICU) is associated with significant morbidity and mortality, as well as a severe prognosis in survivors, in terms of functional, psychological, and cognitive sequelae. During the initial phase, invasive mechanical ventilation aims to promote oxygenation and reduce respiratory effort, with most patients receiving continuous intravenous sedation comprising gamma-aminobutyric acid (GABA) agonists (propofol, midazolam), and opioids. This continuous intravenous sedation is associated with complications, particularly hemodynamic issues (e.g., hypotension, vasopressor dependency), and neurological concerns (e.g., coma, delayed awakening, withdrawal syndrome upon discontinuation of sedation) during the acute phase and is linked to prolonged mechanical ventilation and long-term neurocognitive sequelae.

The use of ketamine as an alternative sedative agent in ICU has garnered considerable attention in recent years. Ketamine has a rapid onset of action and a short duration of effect, potentially beneficial bronchodilatory effects, and minimal impact on hemodynamics or respiratory drive. It also provides effective analgesia. Due to its action on N-methyl-D-aspartate (NMDA) glutamatergic receptors, its mechanism of action differs from other commonly used agents such as propofol and benzodiazepines. Furthermore, emerging research suggests that ketamine may have anti-inflammatory/immunomodulatory and neuroprotective properties that could be advantageous in critically ill patients.

Recent observational studies utilizing low-dose ketamine have suggested an improvement in neurological complications in ICU (e.g., coma, delirium) while other authors have raised concerns about potential renal and hepatic toxicity associated with high doses of ketamine used for sedation. Despite its increasing use, there is currently a lack of high-quality data on the efficacy and safety of ketamine use for sedation in critically ill patients.

In this trial, we hypothesise that, critically ill patients requiring unplanned invasive mechanical ventilation, adjunctive treatment with low dose of ketamine will translate into better outcomes, with higher numbers of days alive outside of the hospital.

The study is a multicenter, randomised, double-blinded placebo-controlled superiority trial involving adult patients requiring unplanned mechanical ventilation, and sedation for more than 6 hours in the ICU. Patients will be randomised within 48 hours following initiation of mechanical ventilation adhering to a 1:1 allocation of ketamine or placebo.

Patients will be randomized to receive either intravenous ketamine or placebo as an adjunctive sedative agent during ICU stay for a maximum duration of 14 days.

Follow-up visits will be performed at day 3, day 14, ICU discharge, day 60, and day 90 after randomization.

The primary endpoint, "days alive and at home," will be assessed at day 60. The end of the research visit is the day 90 follow-up visit. If the patient has been discharged from the hospital, the day-90 visit will consist of telephone contact with the patient by a centralized research assistant and he also will complete the scales at D90.

Data collected by phone consist in Vital status, scales's results and Retrieval of Adverse Events if the patient has been discharged home or with the medical team of the healthcare structure if the patient has been discharged to another structure.

Study Overview

• Status: Not yet recruiting
• Conditions: Critical Illness
• Intervention / Treatment: Drug: Intervention Group; Drug: Placebo

Detailed Description

Phase III study Prospective, multicenter, superiority, double-blind, randomized controlled study with two arms (1:1).

The study includes a screening/baseline visit (V0), followed by daily assessments during the intervention period (V1 to V4), and post-discharge (V5) follow-up visits at Day 60 (V6) and Day 90 (V7).

At screening and baseline (within 48 hours prior to Day 1), eligibility is confirmed, and informed consent is obtained when possible. In cases where prior consent cannot be obtained, deferred consent procedures are applied in accordance with French legislation. Baseline data include medical history, comorbidities, concomitant treatments, clinical examination, and pregnancy testing when applicable.

Randomization is performed at Day 1 (V1). From Day 1 to Day 14 (V4), patients will be receive either intravenous ketamine or placebo as an adjunctive sedative agent during ICU stay for a maximum duration of 14 days.

Until ICU discharge (V5), patients undergo daily assessments including clinical examination, vital status, organ dysfunction (Sequential Organ Failure Assessment [SOFA] score), At Day 14 (V4), opioid and sedative consumption during the treatment period will be quantified.

At Day 60 (V6), ventilator-free days and vasopressor-free days will be assessed.

Duration of delirium and coma are assessed using the RASS/CAM-ICU, at V 4, during the first 14 days following randomization.

Biological monitoring includes daily measurement of serum creatinine and liver function parameters (ASAT, ALAT, gamma-GT, and bilirubin) to evaluate potential renal and hepatic toxicity. Adverse events are collected throughout the ICU stay, and assessed at Day 60 (V6) At ICU discharge (V5), a clinical evaluation and morbidity/mortality assessment are performed if the patient is still hospitalized.

The primary endpoint-the number of days alive and at home-is assessed at Day 60. Secondary outcomes, including mortality (all-cause deaths), are assessed at both Day 60 (V6) and Day 90(V7).

• Study Type: Interventional
• Enrollment (Estimated): 640
• Phase: Phase 3

Contacts and Locations

• Study Contact: Name: Romain Prof SONNEVILLE, MD-PHD; Phone Number: 0033 1 40 25 61 39; Email: romain.sonneville@aphp.fr
• Study Contact Backup: Name: Matthieu Prof LEGRAND, M.D., Ph.D.; Email: Matthieu.Legrand@ucsf.edu

Study Locations

• France
  • Paris, France, 75018
    • Department of Intensive Care Medicine, APHP.Nord, hôpital Bichat Claude Bernard,
    • Contact: Romain Prof SONNEVILLE, MD-PHD; Phone Number: 0033 1 40 25 61 39; Email: romain.sonneville@aphp.fr

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria :

1. Patients over 18 years of age
2. Signed informed consent or inclusion under the emergency provisions of the law (ArticleL1122 -1-3 of the PHC / modified by Order n°2016-800 of June 16 2016 - art. 2)
3. Need for unplanned invasive mechanical ventilation
4. Need for continuous intravenous sedative agents (propofol, midazolam or dexmedetomidine) for more than 6 hours.
5. Affiliation to a social security system (excluding "Aide Médicale d'Etat" [AME])

Exclusion Criteria

1. Refusal to participate in the study
2. Acute brain injuries (i.e. acute stroke, traumatic brain injury, cardiac arrest, brain infections) or conditions (status epilepticus or coma with suspected/confirmed intracranial hypertension at admission requiring deep sedation)
3. Psychosis
4. Status asthmaticus
5. Current liver failure with Model for End-Stage Liver Disease (MELD) > 30
6. Initiation of mechanical ventilation > 48 hours
7. Expected lifespan < 24 hours
8. Patients already receiving a continuous infusion of ketamine
9. Currently participating in another interventional clinical trial investigating sedation or protocols using Ketamine or another drug which may interact with Ketamine or which may have an impact on the evaluation of the trial's judgement criteria.
10. Positive highly sensitive pregnancy test
11. Persons deprived of liberty
12. Persons on a protective judicial measure
13. Breastfeeding
14. Severe arterial hypertension (mean arterial pressure>130 mmHg) despite treatment
15. Hypersensitivity to the active substances or any of the excipients
16. Known contraindications to ketamine according to the SmPC (Severe heart failure, history of stroke, severe uncontrolled hypertension, severe aneurysmal disease, pheochromocytoma)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Intervention group; Ketamine will be started at a dose of 0.2 mg/kg/hour for 4 hours and then adjusted as necessary (+/-0.1 mg/kg/hour every 4 hours) from 0 to 0.6 mg/kg/hour to maintain a targeted RASS of -1 to 0, in addition to standard per local sedation and pain protocols. Duration of treatment: 14 days in maximum	Drug: Intervention Group; Ketamine ® is supplied in 250 mg/5 ml vials containing sterile solution for dilution in sodium chlorure 0.9% for infusions.
Placebo Comparator: Control group; Intravenous placebo will be started at a dose of 0.2 mg/kg/hour for 4 hours and adjusted as necessary (+/-0.1 mg/kg/hour every 4 hours) from 0 to 0.6 mg/kg/hour to maintain a targeted RASS of -1 to 0, in addition to standard sedation per local protocol. Duration of treatment : 14 days in maximum	Drug: Placebo; Placebo : NaCl 0.9% (vials)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of days patients are alive and spent at home	This endpoint will be collected by an independent research assistant, blinded to randomization groups, , and not involved in data monitoring onsite.	At 60 days after ketamine initiation

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of days alive free of encephalopathy	Number of days spent alive without coma or delirium measured on the CAM-ICU	During 14 days after randomization
number of days spent alive without invasive mechanical ventilation	ventilation-free days	At day 60
Number of days spent alive without infusion norepinephrine infusion during ICU stay	Vasopressors-free days	At day 60
Mortality	Defined by the prevalence of all-cause deaths	At Day 60 et Day 90
Renal toxicity,	Defined by the proportion of patients with a KDIGO stage ≥2	At Day 60
Liver toxicity	Defined by the highest bilirubin and phosphatase alkaline level	At Day 60
Quantification of opioid and sedative consumption	During the treatment period, in each arms during the first 14 days	Within the 14 days after randomization
Mean daily pain (BPS)	Mean daily Behavioral Pain Scale (BPS) score assessed during the first 14 days.	During the first 14 days after randomisation
Cumulative incidence of hallucination events		During 14 days after randomization
Mean daily sedation score (RASS)	Mean daily Richmond Agitation-Sedation Scale (RASS) score assessed during the first 14 days.	During the first 14 days after randomisation

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Presence of anxiety and depression, defined by a score ≥11 on the anxiety and depression components of the Hospital Anxiety and Depression scale, respectively at 90 days;	Defined by a score ≥11 on the anxiety and depression components of the Hospital Anxiety and Depression scale, respectively . This outcome will be reported in an ancillary analysis separated from the main report of the trial.	At Day 90
Acute posttraumatic stressdisorder (PTSD)-related	Measured on the ICU memory tool. This outcomes will be reported in an ancillary analysis separated from the main report of the trial	. At Day 90

Collaborators and Investigators

• Sponsor: Assistance Publique - Hôpitaux de Paris
• Investigators: Principal Investigator: Romain Prof SONNEVILLE, MD-PHD, APHP

Publications and helpful links

General Publications

• Devlin JW, Skrobik Y, Gelinas C, Needham DM, Slooter AJC, Pandharipande PP, Watson PL, Weinhouse GL, Nunnally ME, Rochwerg B, Balas MC, van den Boogaard M, Bosma KJ, Brummel NE, Chanques G, Denehy L, Drouot X, Fraser GL, Harris JE, Joffe AM, Kho ME, Kress JP, Lanphere JA, McKinley S, Neufeld KJ, Pisani MA, Payen JF, Pun BT, Puntillo KA, Riker RR, Robinson BRH, Shehabi Y, Szumita PM, Winkelman C, Centofanti JE, Price C, Nikayin S, Misak CJ, Flood PD, Kiedrowski K, Alhazzani W. Clinical Practice Guidelines for the Prevention and Management of Pain, Agitation/Sedation, Delirium, Immobility, and Sleep Disruption in Adult Patients in the ICU. Crit Care Med. 2018 Sep;46(9):e825-e873. doi: 10.1097/CCM.0000000000003299.
• Amer M, Hylander Moller M, Alshahrani M, Shehabi Y, Arabi YM, Alshamsi F, Ingi Sigurethsson M, Rehn M, Chew MS, Kalliomaki ML, Lewis K, Al-Suwaidan FA, Al-Dorzi HM, Al-Fares A, Alsadoon N, Bell CM, Groth CM, Parke R, Mehta S, Wischmeyer PE, Al-Omari A, Olkkola KT, Alhazzani W. Ketamine Analgo-sedation for Mechanically Ventilated Critically Ill Adults: A Rapid Practice Guideline from the Saudi Critical Care Society and the Scandinavian Society of Anesthesiology and Intensive Care Medicine. Anesth Analg. 2025 Aug 1;141(2):309-326. doi: 10.1213/ANE.0000000000007173. Epub 2025 Jul 14.
• de Tymowski C, Depret F, Dudoignon E, Legrand M, Mallet V; Keta-Cov Research Group. Ketamine-induced cholangiopathy in ARDS patients. Intensive Care Med. 2021 Oct;47(10):1173-1174. doi: 10.1007/s00134-021-06482-3. Epub 2021 Jul 27. No abstract available.
• Legrand M, Constantin JM, Burry L, Sonneville R. Ketamine and Traumatic Memory After Intensive Care Unit Discharge: Patient Population and Sedation Concerns. Anesth Analg. 2025 Oct 1;141(4):e48-e49. doi: 10.1213/ANE.0000000000007643. Epub 2025 Jul 17. No abstract available.

Study record dates

Study Major Dates

• Study Start (Estimated): October 19, 2026
• Primary Completion (Estimated): December 19, 2029
• Study Completion (Estimated): January 19, 2030

Study Registration Dates

• First Submitted: May 5, 2026
• First Submitted That Met QC Criteria: May 13, 2026
• First Posted (Actual): May 15, 2026

Study Record Updates

• Last Update Posted (Actual): May 15, 2026
• Last Update Submitted That Met QC Criteria: May 13, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Ketamine; Critical illness; Sedation; Delirium; Mechanical ventilation; Intensive care unit (ICU)
• Additional Relevant MeSH Terms: Neurologic Manifestations; Nervous System Diseases; Mental Disorders; Pathologic Processes; Disease Attributes; Confusion; Neurobehavioral Manifestations; Neurocognitive Disorders; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Delirium; Critical Illness
• Other Study ID Numbers: APHP240938

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No