The Physiology of Circulatory Arrest in Humans

NCT06130033 | Recruiting

• 1 other identifier: H23-00172
• Study Type: observational
• Target: 50
• Locations: 1 country
• Sites: 1

Brief Summary

The purpose of this study is to better understand what happens in the brain during the dying process. This is a prospective observational study conducted at the end of life in the ICU at VGH. At the time of withdrawal of life sustaining therapies the investigators will monitor brain blood flow and oxygenation. The investigators will also collect blood samples to measure biomarkers of brain dysfunction. This may help us to determine when blood flow to the brain stops and when brain function ceases. This information may provide researchers and the medical community as a whole with important information as to the best timing for organ donation. This study is the first step in commencing a research program related to improving the organ donation process. Our goal is to determine how best to provide high quality organs to those who would otherwise die without an organ transplant.

Conditions

Circulatory Arrest

Outcome Measures

Primary Outcomes (1)

• Cerebral Hemodynamics

  To describe the timing and physiologic relationships between brain perfusion relative to cardiovascular function. Specifically, we will assess the pulse pressure (measured with an in situ radial arterial catheter) at which cerebral hemodynamics cease (measured with transcranial Doppler derived middle \[MCA-Fv\] and posterior cerebral artery blood flow velocities \[PCA-Fv\]) following withdrawal of life sustaining measures.

  Up to 52 weeks

Secondary Outcomes (4)

• Feasibility

  Up to 52 weeks

• Brain and Systemic Physiology

  Up to 52 weeks

• Oxygen Extraction Fraction

  Up to 52 weeks

• Brain Biomarker

  Up to 52 weeks

Other Outcomes (1)

• Pathology

  Up to 52 weeks

Interventions

Neuromonitoring DEVICE

Multimodal Neuromonitoring: Transcranial Doppler - middle cerebral artery blood flow velocity Jugular venous bulb oximetry - hemoglobin oxygen saturation at the jugular venous bulb Arterial blood pressure monitoring - mean arterial, systolic and diastolic pressure monitoring at the radial artery via an in situ radial arterial line catheter Pulmonary artery catheter - to measure continuous cardiac output and mixed venous oxygen saturation Near infrared spectroscopy - to measure regional cerebral saturation of oxygen

Eligibility Criteria

• Age: 19 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Critically ill patients who will undergoing palliative measures following prognostication.

You may qualify if:

• a) Age \> 18 years
• b) anticipated withdrawal of life-sustaining measures (WLSM) within the next 24 hours

You may not qualify if:

• No in-situ arterial line
• No legal authorized representative
• Neurological brain death declared

Sponsors & Collaborators

• University of British Columbia: lead

Study Sites (1)

Vancouver General Hospital

Vancouver, British Columbia, V5Z1M9, Canada

RECRUITING

Related Publications (1)

• Bird JD, Hornby L, Hirsch-Reinshagen V, Allen CP, Isac G, Gooderham PA, Shemie SD, Dhanani S, Thiara S, Stukas S, Grey R, Foster DA, Maier LE, LeBlanc AE, Kanji HD, Morelli TF, Agbay AM, Wellington CL, Chahal D, Belanger EC, Ren H, Mattu PS, Su S, Hrazdil CT, Percy J, Sangha P, Plewes LV, Sweet DD, Romano KR, Vu EN, Chittock DR, Dhingra VK, Henderson WR, Garraway NR, Morad Hameed S, Finlayson GN, MacLeod DB, Gibbons TD, Ainslie PN, Hoiland RL, Griesdale DE, Ronco JJ, Sekhon MS. Characterizing the physiology of circulatory arrest in humans. Nat Med. 2025 Oct;31(10):3542-3552. doi: 10.1038/s41591-025-03889-z. Epub 2025 Oct 16.

  PMID: 41102468 DERIVED

Biospecimen

Retention: SAMPLES WITH DNA

Arterial and jugular venous serum / plasma. Post-mortem brain and spinal cord tissue.

Study Officials

• Mypinder S Sekhon, MD PhD

  University of British Columbia

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Mypinder Sekhon, MD PhD

CONTACT

6048754111; myp@mail.ubc.ca

Rebecca Grey, BSc

CONTACT

604-875-4111; Rebecca.Grey@vch.ca

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: October 15, 2023
• First Posted: November 13, 2023
• Study Start: June 1, 2023
• Primary Completion (Estimated): June 1, 2026
• Study Completion (Estimated): June 1, 2026
• Last Updated: November 13, 2024

Record last verified: 2024-11

Locations

CA (1)