Cardiopulmonary Resuscitation, Death, Sudden, Cardiac, Out-Of-Hospital Cardiac Arrest, Therapeutic Hypothermia
Conditions
Keywords
Return of Spontaneous Circulation
Brief summary
The PRE-hospital Cooling to improvE carDiac arrEst Neurological outComEs (PRECEDENCE) study is a pilot feasibility trial evaluating the implementation of pre-hospital targeted temperature management (TTM) using a wearable surface cooling device (CarbonCool® vest) in adult out-of-hospital cardiac arrest (OHCA) patients with return of spontaneous circulation (ROSC). The study aims to assess feasibility, fidelity, acceptability, and safety of initiating cooling in the field by emergency medical services (EMS) prior to hospital arrival. Results will inform the design of a larger definitive trial to determine the clinical effectiveness of early pre-hospital TTM in improving neurological outcomes.
Detailed description
Background: Despite advances in resuscitation, neurological recovery after out-of-hospital cardiac arrest (OHCA) remains poor. Current hospital-initiated targeted temperature management (TTM) often begins several hours after ROSC, potentially missing the optimal neuroprotective window. Early or ultra-early cooling during the pre-hospital phase may mitigate ischemia-reperfusion brain injury, but evidence from real-world EMS settings is limited. Rationale: The PRECEDENCE study tests the operational feasibility of initiating TTM in the pre-hospital environment using a novel, power-free CarbonCool® cooling vest designed for rapid application by paramedics immediately after ROSC. The vest provides conductive surface cooling without interfering with resuscitation, transport, or diagnostics. Study Design: PRECEDENCE is a pilot feasibility trial conducted by the Singapore Civil Defence Force (SCDF) and collaborating hospital. Eligible OHCA patients attended by SCDF Division 4 paramedics will be allocated to either (a) pre-hospital TTM using the CarbonCool® vest or (b) standard pre-hospital care, depending on predefined eligibility and operational criteria. Both groups will be prospectively followed through hospital discharge. Outcomes: The primary outcome is feasibility of implementing pre-hospital TTM, evaluated through recruitment rates, intervention delivery, protocol fidelity, and provider acceptability. Secondary outcomes include hospital TTM uptake, time from ROSC to target temperature, neurological outcome at discharge (CPC 1-2), and predefined safety endpoints (overshoot cooling \< 33 °C, hemodynamically significant bradyarrhythmias, and skin injury). Significance: By assessing real-world feasibility and safety of early pre-hospital cooling, this pilot will provide critical implementation data and guide protocol refinements for a future multi-division or national randomized trial.
Interventions
DEVICECarbonCool® Cooling Vest
The CarbonCool® vest is a power-free, thermoplastic polyurethane (TPU) surface cooling device containing a proprietary carbon-based cooling medium capable of high heat exchange (35 W/mK). It is designed for rapid pre-hospital application and continuous cooling during patient transport.
Sponsors
Singapore General Hospital
Singapore Civil Defence Force
National University Heart Centre, Singapore
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Masking description
This is an open-label study. Masking of participants, care providers, and outcome assessors is not feasible due to the visible and operational nature of the cooling intervention in the pre-hospital environment. All analyses will be performed by the research team using de-identified data to minimize potential assessment bias.
Intervention model description
This study design to evaluate the feasibility of implementing pre-hospital targeted temperature management (TTM) using a wearable cooling vest compared with standard pre-hospital care. Eligible out-of-hospital cardiac arrest (OHCA) patients who achieve return of spontaneous circulation (ROSC) are assigned to the intervention (CarbonCool® vest) based on predefined clinical eligibility and operational criteria. They will be compared against historical controls as well as eligible patients (by inclusion/exclusion criteria) managed by EMS from Divisions 1 to 3. Both groups are prospectively observed for safety, and clinical outcomes.
Eligibility
Sex/Gender
ALL
Age
16 Years to 80 Years
Healthy volunteers
No
Inclusion criteria
1. Out-of-hospital cardiac arrest (OHCA) of any rhythm attended by Singapore Civil Defence Force (SCDF) paramedics. 2. Return of spontaneous circulation (ROSC) achieved in the pre-hospital setting. 3. Age ≥16 years and ≤80 years. 4. Patient remains comatose after ROSC, with Glasgow Coma Scale (GCS) ≤8.
Exclusion criteria
1. Age \>80 years. 2. Traumatic cause of cardiac arrest. 3. Tympanic temperature \<34°C at time of assessment. 4. Pregnant females. 5. Termination of resuscitation in the Emergency Department. 6. Withdrawal of life support within 24 hours of Coronary Care Unit (CCU) admission.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Recruitment feasibility | Through study completion, anticipated to be one year | Proportion of EMS-attended, eligible OHCA patients who received pre-hospital TTM |
| Intervention feasibility | Through study completion, anticipated to be one year | Proportion of recruited OHCA patients receiving the TTM protocol as intended |
| Proportion of cases with complete adherence of workflow and case report forms | Through study completion, anticipated to be one year | Adherence of paramedics to workflow and case report forms |
| Acceptability of Intervention Measure (AIM) | Time frame within 3 months of case recruitment | Paramedic acceptability of the intervention will be assessed using the validated Acceptability of Intervention Measure (AIM). The AIM consists of a 4-item questionnaire rated on a 5-point Likert scale, with higher scores indicating greater acceptability of the intervention. Range score between 4 to 20. |
| Intervention Appropriateness Measure (IAM) | Time frame within 3 months of case recruitment | Perceived appropriateness of the intervention will be evaluated using the validated Intervention Appropriateness Measure (IAM). The IAM is a 4-item questionnaire rated on a 5-point Likert scale, with higher scores indicating greater perceived fit and relevance of the intervention for prehospital care. Range score between 4 to 20. |
| Feasibility of Intervention Measure (FIM) scores | Time frame within 3 months of case recruitment | Feasibility of implementing the intervention in the operational prehospital setting will be assessed using the validated Feasibility of Intervention Measure (FIM). The FIM comprises 4 items rated on a 5-point Likert scale, with higher scores indicating greater perceived feasibility. Range score between 4 to 20. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Proportion of Eligible OHCA Patients Receiving Hospital TTM | 6 hours | Percentage of out-of-hospital cardiac arrest (OHCA) patients who meet inclusion criteria and subsequently receive targeted temperature management (TTM) in hospital. |
| Time to Achieve Target Core Temperature After ROSC | 12 hours | Duration (in minutes) from return of spontaneous circulation (ROSC) to achievement of target core temperature |
| Good Neurological Outcome at Hospital Discharge | To hospital discharge, with an average of 30 days | Proportion of patients with a Cerebral Performance Category (CPC) score of 1 or 2 at hospital discharge. |
Countries
Singapore
Contacts
CONTACTShir Lynn Lim, MBBS
Outcome results
None listed