Impacts of Low-Dose Dexmedetomidine on Sleep Quality in Mechanically Ventilated ICU Patients
NCT ID: NCT03335527
Last Updated: 2019-12-11
Study Results
Results pending
The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.
Basic Information
Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.
Recruitment Status
COMPLETED
Clinical Phase
PHASE4
Total Enrollment
80 participants
Study Classification
INTERVENTIONAL
Study Start Date
2017-11-17
Study Completion Date
2019-11-30
Brief Summary
Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.
Sleep disturbances frequently occur in intensive care unit (ICU) patients undergoing mechanical ventilation. In a previous study, sedative dose dexmedetomidine (median 0.6 microgram/kg/h) improved sleep quality in mechanically ventilated patients. However, for mechanically ventilated patients, light sedation is better than deep sedation for the outcomes, which is manifested as shortened length of ICU stay, shortened duration of mechanical ventilation, and decreased mortality. In a recent study of the investigators, non-sedative low-dose dexmedetomidine (0.1 microgram/kg/h) improved sleep quality in non-mechanically ventilated elderly patients admitted to the ICU after surgery. The investigators hypothesize that, in mechanically ventilated patients who are admitted to the ICU after surgery, low-dose dexmedetomidine may also improve sleep quality.
Detailed Description
Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.
Sleep is severely disturbed in mechanically ventilated ICU patients, especially those after surgery. Polysomnographic studies performed in these patients demonstrated a severe increase in sleep fragmentation, prolonged N1 and N2 sleep, reduced N3 and REM sleep, and an abnormal distribution of sleep because almost half of the total sleep time occurred during the daytime. Patients reported little or no sleep, poor sleep quality, frequent awakening, and daytime sleep.
Many factors are responsible for sleep disturbance in postoperative ICU patients with mechanical ventilation, these include the severity of surgical stress and illness, ICU environment, mechanical ventilation, pain, sedatives and analgesics, and various other therapy. Sleep disturbances produce harmful effects on postoperative outcomes. It is associated with increased prevalence of delirium, cardiac events and worse functional recovery. Moreover, patients with sleep disturbances are more sensitive to pain.
Unlike other sedative agents, dexmedetomidine exerts its sedative effects through an endogenous sleep-promoting pathway and produces a N2 sleep-like state. In mechanically ventilated ICU patients, nighttime infusion of sedative dose of dexmedetomidine (median 0.6 microgram/kg/h) preserved the day-night cycle of sleep and improved the sleep architecture by increasing sleep efficiency and stage N2 sleep.
Studies showed that, in mechanically ventilated patients, light sedation is better than deep sedation for patients' outcomes, including shortened duration of ventilation and length of ICU stay, and decreased mortality. Some studies even showed that no sedation (analgesia only) is better than sedation. In a recent study of non mechanical ventilated elderly patients who were admitted to the ICU after surgery, non-sedative low-dose dexmedetomidine infusion (at a rate of 0.1 microgram/kg/h during the night on the day of surgery) increased the percentage of stage N2 sleep (and decreased the percentage of N1 sleep), prolonged the total sleep time, increased the sleep efficiency, and improved the subjective sleep quality.
The investigators hypothesize that, in mechanically ventilated patients who were admitted to the ICU after surgery, low-dose dexmedetomidine infusion may also improve sleep quality.
Many factors are responsible for sleep disturbance in postoperative ICU patients with mechanical ventilation, these include the severity of surgical stress and illness, ICU environment, mechanical ventilation, pain, sedatives and analgesics, and various other therapy. Sleep disturbances produce harmful effects on postoperative outcomes. It is associated with increased prevalence of delirium, cardiac events and worse functional recovery. Moreover, patients with sleep disturbances are more sensitive to pain.
Unlike other sedative agents, dexmedetomidine exerts its sedative effects through an endogenous sleep-promoting pathway and produces a N2 sleep-like state. In mechanically ventilated ICU patients, nighttime infusion of sedative dose of dexmedetomidine (median 0.6 microgram/kg/h) preserved the day-night cycle of sleep and improved the sleep architecture by increasing sleep efficiency and stage N2 sleep.
Studies showed that, in mechanically ventilated patients, light sedation is better than deep sedation for patients' outcomes, including shortened duration of ventilation and length of ICU stay, and decreased mortality. Some studies even showed that no sedation (analgesia only) is better than sedation. In a recent study of non mechanical ventilated elderly patients who were admitted to the ICU after surgery, non-sedative low-dose dexmedetomidine infusion (at a rate of 0.1 microgram/kg/h during the night on the day of surgery) increased the percentage of stage N2 sleep (and decreased the percentage of N1 sleep), prolonged the total sleep time, increased the sleep efficiency, and improved the subjective sleep quality.
The investigators hypothesize that, in mechanically ventilated patients who were admitted to the ICU after surgery, low-dose dexmedetomidine infusion may also improve sleep quality.
Conditions
See the medical conditions and disease areas that this research is targeting or investigating.
Aged
Postoperative Period
Intensive Care Units
Mechanical Ventilation Complication
Sleep Disorders
Dexmedetomidine
Keywords
Explore important study keywords that can help with search, categorization, and topic discovery.
Aged
Postoperative period
Intensive Care Unit
Mechanical ventilation
Sleep quality
Dexmedetomidine
Study Design
Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.
Allocation Method
RANDOMIZED
Intervention Model
PARALLEL
Primary Study Purpose
PREVENTION
Blinding Strategy
QUADRUPLE
Participants
Caregivers
Investigators
Outcome Assessors
Study Groups
Review each arm or cohort in the study, along with the interventions and objectives associated with them.
Dexmedetomidine group
Dexmedetomidine is infused at a rate of 0.1 ug/kg/h during mechanical ventilation, for a maximum of 3 days
Group Type
EXPERIMENTAL
Dexmedetomidine
Intervention Type
DRUG
Dexmedetomidine is administered as a continuous intravenous infusion at a rate of 0.1-0.2 ug/kg/h (0.025-0.05 ml/kg/h) from study recruitment in the ICU during mechanical ventilation, for no more than 72 hours.
Placebo group
Placebo (normal saline) is infused at a same rate as in the dexmedetomidine group during mechanical ventilation, for a maximum of 3 days
Group Type
PLACEBO_COMPARATOR
Placebo (normal saline)
Intervention Type
DRUG
Placebo (normal saline) is administered as a continuous intravenous infusion at a rate of 0.025-0.05 ml/kg/h from study recruitment in the ICU during mechanical ventilation, for no more than 72 hours.
Interventions
Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.
Dexmedetomidine
Dexmedetomidine is administered as a continuous intravenous infusion at a rate of 0.1-0.2 ug/kg/h (0.025-0.05 ml/kg/h) from study recruitment in the ICU during mechanical ventilation, for no more than 72 hours.
Intervention Type
DRUG
Placebo (normal saline)
Placebo (normal saline) is administered as a continuous intravenous infusion at a rate of 0.025-0.05 ml/kg/h from study recruitment in the ICU during mechanical ventilation, for no more than 72 hours.
Intervention Type
DRUG
Other Intervention Names
Discover alternative or legacy names that may be used to describe the listed interventions across different sources.
Dexmedetomidine hydrochloride
Normal saline
Eligibility Criteria
Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.
Inclusion Criteria
* aged 18 years or older;
* admitted to the ICU after surgery;
* with an expected duration of mechanical ventilation of more than 12 hours (admitted before 21:00 on the day of surgery and extubated after 06:00 on the first day after surgery).
* admitted to the ICU after surgery;
* with an expected duration of mechanical ventilation of more than 12 hours (admitted before 21:00 on the day of surgery and extubated after 06:00 on the first day after surgery).
Exclusion Criteria
* refused to participate;
* aged less than 18 years;
* pregnant;
* preoperative history of schizophrenia, epilepsy, parkinsonism, or myasthenia gravis;
* inability to communicate in the preoperative period (coma, profound dementia, or language barrier);
* brain injury or neurosurgery;
* known preoperative left ventricular ejection fraction less than 30%, sick sinus syndrome, severe sinus bradycardia (\<50 beats per min), or second degree or greater atrioventricular block without pacemaker, systolic blood pressure less than 90 mmHg despite continuous infusions of vasopressors before the start of study drugs infusion;
* serious hepatic dysfunction (Child-Pugh class C);
* serious renal dysfunction (undergoing dialysis before surgery);
* less likelihood to survive for more than 24 hours;
* preoperative history of sleep disorders (requirement of hypnotics/sedatives during the last month) or history of obstructive sleep apnea syndrome (diagnosed with obstructive sleep apnea);
* allergy to the study drugs;
* other conditions that are considered unsuitable for study participation.
* aged less than 18 years;
* pregnant;
* preoperative history of schizophrenia, epilepsy, parkinsonism, or myasthenia gravis;
* inability to communicate in the preoperative period (coma, profound dementia, or language barrier);
* brain injury or neurosurgery;
* known preoperative left ventricular ejection fraction less than 30%, sick sinus syndrome, severe sinus bradycardia (\<50 beats per min), or second degree or greater atrioventricular block without pacemaker, systolic blood pressure less than 90 mmHg despite continuous infusions of vasopressors before the start of study drugs infusion;
* serious hepatic dysfunction (Child-Pugh class C);
* serious renal dysfunction (undergoing dialysis before surgery);
* less likelihood to survive for more than 24 hours;
* preoperative history of sleep disorders (requirement of hypnotics/sedatives during the last month) or history of obstructive sleep apnea syndrome (diagnosed with obstructive sleep apnea);
* allergy to the study drugs;
* other conditions that are considered unsuitable for study participation.
Minimum Eligible Age
18 Years
Eligible Sex
ALL
Accepts Healthy Volunteers
No
Sponsors
Meet the organizations funding or collaborating on the study and learn about their roles.
Peking University First Hospital
OTHER
Sponsor Role
lead
Responsible Party
Identify the individual or organization who holds primary responsibility for the study information submitted to regulators.
Dong-Xin Wang
Professor and Chairman, Department of Anesthesiology and Critical Care Medicine
Responsibility Role
PRINCIPAL_INVESTIGATOR
Principal Investigators
Learn about the lead researchers overseeing the trial and their institutional affiliations.
Dong-Xin Wang, MD, PhD
Role: PRINCIPAL_INVESTIGATOR
Peking University First Hospital
Locations
Explore where the study is taking place and check the recruitment status at each participating site.
Peking University First Hospital
Beijing, Beijing Municipality, China
Site Status
Countries
Review the countries where the study has at least one active or historical site.
China
References
Explore related publications, articles, or registry entries linked to this study.
Friese RS. Sleep and recovery from critical illness and injury: a review of theory, current practice, and future directions. Crit Care Med. 2008 Mar;36(3):697-705. doi: 10.1097/CCM.0B013E3181643F29.
Reference Type
BACKGROUND
Elliott R, McKinley S, Cistulli P. The quality and duration of sleep in the intensive care setting: an integrative review. Int J Nurs Stud. 2011 Mar;48(3):384-400. doi: 10.1016/j.ijnurstu.2010.11.006. Epub 2010 Dec 24.
Reference Type
BACKGROUND
Cooper AB, Thornley KS, Young GB, Slutsky AS, Stewart TE, Hanly PJ. Sleep in critically ill patients requiring mechanical ventilation. Chest. 2000 Mar;117(3):809-18. doi: 10.1378/chest.117.3.809.
Reference Type
BACKGROUND
Parsons EC, Kross EK, Caldwell ES, Kapur VK, McCurry SM, Vitiello MV, Hough CL. Post-discharge insomnia symptoms are associated with quality of life impairment among survivors of acute lung injury. Sleep Med. 2012 Sep;13(8):1106-9. doi: 10.1016/j.sleep.2012.05.010. Epub 2012 Jul 2.
Reference Type
BACKGROUND
Combes A, Costa MA, Trouillet JL, Baudot J, Mokhtari M, Gibert C, Chastre J. Morbidity, mortality, and quality-of-life outcomes of patients requiring >or=14 days of mechanical ventilation. Crit Care Med. 2003 May;31(5):1373-81. doi: 10.1097/01.CCM.0000065188.87029.C3.
Reference Type
BACKGROUND
Granja C, Lopes A, Moreira S, Dias C, Costa-Pereira A, Carneiro A; JMIP Study Group. Patients' recollections of experiences in the intensive care unit may affect their quality of life. Crit Care. 2005 Apr;9(2):R96-109. doi: 10.1186/cc3026. Epub 2005 Jan 31.
Reference Type
BACKGROUND
Aurell J, Elmqvist D. Sleep in the surgical intensive care unit: continuous polygraphic recording of sleep in nine patients receiving postoperative care. Br Med J (Clin Res Ed). 1985 Apr 6;290(6474):1029-32. doi: 10.1136/bmj.290.6474.1029.
Reference Type
BACKGROUND
Friese RS, Diaz-Arrastia R, McBride D, Frankel H, Gentilello LM. Quantity and quality of sleep in the surgical intensive care unit: are our patients sleeping? J Trauma. 2007 Dec;63(6):1210-4. doi: 10.1097/TA.0b013e31815b83d7.
Reference Type
BACKGROUND
Gehlbach BK, Chapotot F, Leproult R, Whitmore H, Poston J, Pohlman M, Miller A, Pohlman AS, Nedeltcheva A, Jacobsen JH, Hall JB, Van Cauter E. Temporal disorganization of circadian rhythmicity and sleep-wake regulation in mechanically ventilated patients receiving continuous intravenous sedation. Sleep. 2012 Aug 1;35(8):1105-14. doi: 10.5665/sleep.1998.
Reference Type
BACKGROUND
Elliott R, McKinley S, Cistulli P, Fien M. Characterisation of sleep in intensive care using 24-hour polysomnography: an observational study. Crit Care. 2013 Mar 18;17(2):R46. doi: 10.1186/cc12565.
Reference Type
BACKGROUND
Slatore CG, Goy ER, O'hearn DJ, Boudreau EA, O'Malley JP, Peters D, Ganzini L. Sleep quality and its association with delirium among veterans enrolled in hospice. Am J Geriatr Psychiatry. 2012 Apr;20(4):317-26. doi: 10.1097/JGP.0b013e3182487680.
Reference Type
BACKGROUND
Kjolhede P, Langstrom P, Nilsson P, Wodlin NB, Nilsson L. The impact of quality of sleep on recovery from fast-track abdominal hysterectomy. J Clin Sleep Med. 2012 Aug 15;8(4):395-402. doi: 10.5664/jcsm.2032.
Reference Type
BACKGROUND
Fernandes NM, Nield LE, Popel N, Cantor WJ, Plante S, Goldman L, Prabhakar M, Manlhiot C, McCrindle BW, Miner SE. Symptoms of disturbed sleep predict major adverse cardiac events after percutaneous coronary intervention. Can J Cardiol. 2014 Jan;30(1):118-24. doi: 10.1016/j.cjca.2013.07.009. Epub 2013 Oct 16.
Reference Type
BACKGROUND
Finan PH, Goodin BR, Smith MT. The association of sleep and pain: an update and a path forward. J Pain. 2013 Dec;14(12):1539-52. doi: 10.1016/j.jpain.2013.08.007.
Reference Type
BACKGROUND
Kanji S, Mera A, Hutton B, Burry L, Rosenberg E, MacDonald E, Luks V. Pharmacological interventions to improve sleep in hospitalised adults: a systematic review. BMJ Open. 2016 Jul 29;6(7):e012108. doi: 10.1136/bmjopen-2016-012108.
Reference Type
BACKGROUND
Stanchina ML, Abu-Hijleh M, Chaudhry BK, Carlisle CC, Millman RP. The influence of white noise on sleep in subjects exposed to ICU noise. Sleep Med. 2005 Sep;6(5):423-8. doi: 10.1016/j.sleep.2004.12.004. Epub 2005 Mar 31.
Reference Type
BACKGROUND
Freedman NS, Gazendam J, Levan L, Pack AI, Schwab RJ. Abnormal sleep/wake cycles and the effect of environmental noise on sleep disruption in the intensive care unit. Am J Respir Crit Care Med. 2001 Feb;163(2):451-7. doi: 10.1164/ajrccm.163.2.9912128.
Reference Type
BACKGROUND
Parthasarathy S, Tobin MJ. Effect of ventilator mode on sleep quality in critically ill patients. Am J Respir Crit Care Med. 2002 Dec 1;166(11):1423-9. doi: 10.1164/rccm.200209-999OC. Epub 2002 Sep 5.
Reference Type
BACKGROUND
Fanfulla F, Ceriana P, D'Artavilla Lupo N, Trentin R, Frigerio F, Nava S. Sleep disturbances in patients admitted to a step-down unit after ICU discharge: the role of mechanical ventilation. Sleep. 2011 Mar 1;34(3):355-62. doi: 10.1093/sleep/34.3.355.
Reference Type
BACKGROUND
Trompeo AC, Vidi Y, Locane MD, Braghiroli A, Mascia L, Bosma K, Ranieri VM. Sleep disturbances in the critically ill patients: role of delirium and sedative agents. Minerva Anestesiol. 2011 Jun;77(6):604-12.
Reference Type
BACKGROUND
Weinhouse GL, Watson PL. Sedation and sleep disturbances in the ICU. Crit Care Clin. 2009 Jul;25(3):539-49, ix. doi: 10.1016/j.ccc.2009.04.003.
Reference Type
BACKGROUND
Gabor JY, Cooper AB, Crombach SA, Lee B, Kadikar N, Bettger HE, Hanly PJ. Contribution of the intensive care unit environment to sleep disruption in mechanically ventilated patients and healthy subjects. Am J Respir Crit Care Med. 2003 Mar 1;167(5):708-15. doi: 10.1164/rccm.2201090.
Reference Type
BACKGROUND
Schiza SE, Simantirakis E, Bouloukaki I, Mermigkis C, Arfanakis D, Chrysostomakis S, Chlouverakis G, Kallergis EM, Vardas P, Siafakas NM. Sleep patterns in patients with acute coronary syndromes. Sleep Med. 2010 Feb;11(2):149-53. doi: 10.1016/j.sleep.2009.07.016. Epub 2010 Jan 18.
Reference Type
BACKGROUND
Nelson LE, Lu J, Guo T, Saper CB, Franks NP, Maze M. The alpha2-adrenoceptor agonist dexmedetomidine converges on an endogenous sleep-promoting pathway to exert its sedative effects. Anesthesiology. 2003 Feb;98(2):428-36. doi: 10.1097/00000542-200302000-00024.
Reference Type
BACKGROUND
Wunsch H, Kahn JM, Kramer AA, Wagener G, Li G, Sladen RN, Rubenfeld GD. Dexmedetomidine in the care of critically ill patients from 2001 to 2007: an observational cohort study. Anesthesiology. 2010 Aug;113(2):386-94. doi: 10.1097/ALN.0b013e3181e74116.
Reference Type
BACKGROUND
Pandharipande PP, Pun BT, Herr DL, Maze M, Girard TD, Miller RR, Shintani AK, Thompson JL, Jackson JC, Deppen SA, Stiles RA, Dittus RS, Bernard GR, Ely EW. Effect of sedation with dexmedetomidine vs lorazepam on acute brain dysfunction in mechanically ventilated patients: the MENDS randomized controlled trial. JAMA. 2007 Dec 12;298(22):2644-53. doi: 10.1001/jama.298.22.2644.
Reference Type
BACKGROUND
Xia ZQ, Chen SQ, Yao X, Xie CB, Wen SH, Liu KX. Clinical benefits of dexmedetomidine versus propofol in adult intensive care unit patients: a meta-analysis of randomized clinical trials. J Surg Res. 2013 Dec;185(2):833-43. doi: 10.1016/j.jss.2013.06.062. Epub 2013 Jul 24.
Reference Type
BACKGROUND
Alexopoulou C, Kondili E, Diamantaki E, Psarologakis C, Kokkini S, Bolaki M, Georgopoulos D. Effects of dexmedetomidine on sleep quality in critically ill patients: a pilot study. Anesthesiology. 2014 Oct;121(4):801-7. doi: 10.1097/ALN.0000000000000361.
Reference Type
BACKGROUND
Hughes CG, Girard TD, Pandharipande PP. Daily sedation interruption versus targeted light sedation strategies in ICU patients. Crit Care Med. 2013 Sep;41(9 Suppl 1):S39-45. doi: 10.1097/CCM.0b013e3182a168c5.
Reference Type
BACKGROUND
Treggiari MM, Romand JA, Yanez ND, Deem SA, Goldberg J, Hudson L, Heidegger CP, Weiss NS. Randomized trial of light versus deep sedation on mental health after critical illness. Crit Care Med. 2009 Sep;37(9):2527-34. doi: 10.1097/CCM.0b013e3181a5689f.
Reference Type
BACKGROUND
Balzer F, Weiss B, Kumpf O, Treskatsch S, Spies C, Wernecke KD, Krannich A, Kastrup M. Early deep sedation is associated with decreased in-hospital and two-year follow-up survival. Crit Care. 2015 Apr 28;19(1):197. doi: 10.1186/s13054-015-0929-2.
Reference Type
BACKGROUND
Porhomayon J, Joude P, Adlparvar G, El-Solh AA, Nader ND. The Impact of High Versus Low Sedation Dosing Strategy on Cognitive Dysfunction in Survivors of Intensive Care Units: A Systematic Review and Meta-Analysis. J Cardiovasc Thorac Res. 2015;7(2):43-8. doi: 10.15171/jcvtr.2015.10.
Reference Type
BACKGROUND
Toft P, Olsen HT, Jorgensen HK, Strom T, Nibro HL, Oxlund J, Wian KA, Ytrebo LM, Kroken BA, Chew M. Non-sedation versus sedation with a daily wake-up trial in critically ill patients receiving mechanical ventilation (NONSEDA Trial): study protocol for a randomised controlled trial. Trials. 2014 Dec 20;15:499. doi: 10.1186/1745-6215-15-499.
Reference Type
BACKGROUND
Nedergaard HK, Jensen HI, Lauridsen JT, Sjogaard G, Toft P. Non-sedation versus sedation with a daily wake-up trial in critically ill patients receiving mechanical ventilation--effects on physical function: study protocol for a randomized controlled trial: a substudy of the NONSEDA trial. Trials. 2015 Jul 23;16:310. doi: 10.1186/s13063-015-0856-1.
Reference Type
BACKGROUND
Nedergaard HK, Jensen HI, Stylsvig M, Lauridsen JT, Toft P. Non-sedation versus sedation with a daily wake-up trial in critically ill patients recieving mechanical ventilation - effects on long-term cognitive function: Study protocol for a randomized controlled trial, a substudy of the NONSEDA trial. Trials. 2016 Jun 1;17(1):269. doi: 10.1186/s13063-016-1390-5.
Reference Type
BACKGROUND
Wu XH, Cui F, Zhang C, Meng ZT, Wang DX, Ma J, Wang GF, Zhu SN, Ma D. Low-dose Dexmedetomidine Improves Sleep Quality Pattern in Elderly Patients after Noncardiac Surgery in the Intensive Care Unit: A Pilot Randomized Controlled Trial. Anesthesiology. 2016 Nov;125(5):979-991. doi: 10.1097/ALN.0000000000001325.
Reference Type
BACKGROUND
Su X, Meng ZT, Wu XH, Cui F, Li HL, Wang DX, Zhu X, Zhu SN, Maze M, Ma D. Dexmedetomidine for prevention of delirium in elderly patients after non-cardiac surgery: a randomised, double-blind, placebo-controlled trial. Lancet. 2016 Oct 15;388(10054):1893-1902. doi: 10.1016/S0140-6736(16)30580-3. Epub 2016 Aug 16.
Reference Type
BACKGROUND
International Conference on Harmonisation of technical requirements for registration of pharmaceuticals for human use.. ICH harmonized tripartite guideline: Guideline for Good Clinical Practice. J Postgrad Med. 2001 Jan-Mar;47(1):45-50. No abstract available.
Reference Type
BACKGROUND
Sun YM, Zhu SN, Zhang C, Li SL, Wang DX. Effect of low-dose dexmedetomidine on sleep quality in postoperative patients with mechanical ventilation in the intensive care unit: A pilot randomized trial. Front Med (Lausanne). 2022 Aug 31;9:931084. doi: 10.3389/fmed.2022.931084. eCollection 2022.
Reference Type
DERIVED
Other Identifiers
Review additional registry numbers or institutional identifiers associated with this trial.
2017[13]
Identifier Type: -
Identifier Source: org_study_id