IschemiaEDIRNCT05297266
Early Discovery of Ischemia After Replantation Surgery of the Extremities
A study testing IscAlert in people with Ischemia and Blood Circulation Disorder, run by Oslo University Hospital at 1 site in Norway.
Trial summary
Investigators will test if changes in CO2 is detected postoperatively in ischemic tissue in a replanted extremity of a traumatically amputated upper or lower extremity. IscAlert is measuring continuously CO2 in muscular and subcutaneous tissue. Read more about this study
- Who is it for?
- Ages 18 to 100 years
- Conditions the study is for
- Ischemia, Blood Circulation Disorder, Carbon Dioxide
- What is being tested?
- IscAlert
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 60 participants
- Where
- 1 siteNorway
- Study dates
- 15 Nov 2022to 30 Sep 2027
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 100 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Patients must be in need of extremity replantation surgery
- Subject must be ≥ 18 years
- Able to give written signed informed consent
Who cannot join
- None
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Early Discovery of Ischemia After Replantation Surgery of the Extremities (EDIR-study) ; An Open, Prospective, Intervention Study
Investigators will test if changes in CO2 is detected postoperatively in ischemic tissue in a replanted extremity of a traumatically amputated upper or lower extremity. IscAlert is measuring continuously CO2 in muscular and subcutaneous tissue. IscAlert is inserted distal to the operative field into normal muscle and/or subcutaneous tissue in the replanted extremity. Local tissue CO2 and temperature will be monitored continuously postoperatively for the next 10 days. If a reduced or totally obstructed blood flow appear (thrombosis), an increase in tissue CO2 and a lower local temperature will emerge rapidly as a sign of ischemia. This will be detected by the sensor which will alarm the investigators. This will lead to assessment of the replanted extremity and if restricted blood flow is diagnosed, a reoperation will be performed. After reoperation new sensors will be implanted for another ten days if applicable. Sixty patients will be enrolled to undergo the procedures. The IscAlert will be removed from the patient before the patient is discharged from the hospital or a maximum of 10 days (the event that occurs first). 500 devices is planned to be used in this clinical study.
Read the detailed description
This is an open, prospective, interventional, single-center clinical investigation designed to examine the feasibility and safety of the IscAlert™ device in patients scheduled for extremity replant surgery. Sixty patients will be enrolled to undergo the procedures using a total of 400 devices depending on the injuries.
IscAlert is 0.8 mm in diameter and in vitro testing, shows stable and accurate measurements of pCO2. More than 200 animal experiments have been done with the sensor. The experiments have shown that the sensor detects ischemia (Increased CO2-measurements) in real time in the following organs and tissues: Brain, heart, liver, kidneys, pancreas, intestines, musculature and subcutaneous tissue. Sensitivity and specificity are close to 100%. The sensors are inserted into tissue by a split needle technique. The split needle is the size of a 3-gauge peripheral venous catheter. In animal studies, no complications have been detected when using the sensor.
The IscAlert catheters are connected to an electronics unit that is fixed to the skin with an adhesive plaster or glue outside the sterile area. The electrical signals are redirected to a PC approved for clinical use which continuously records tissue pressures of CO2.
IscAlert is inserted into normal muscle and/or subcutaneous tissue distal on the replanted limb to be operated at the end of surgery or immediate postoperatively. The insertion is far away from the operating field. The insertion is done under sterile conditions in accordance with standard sterility criteria at the hospital. No pain during insertion will occur because of insertion is performed during anesthesia (general or regional). Also, the insertion can be compared to an intramuscular injection.
Postoperatively, the IscAlert sensor will continuously monitoring tissue CO2 and temperature. If ischemia occur, for examples caused by a thrombus, an increase in tissue CO2 and a lower temperature will evolve. This will be detected by the sensor which will alarm the investigators. This will lead to assessment of the replanted extremity and if restricted blood flow is diagnosed or suspected, a reoperation will be performed.
Sixty patients will be enrolled to undergo the procedures. The IscAlert will be removed from the patient before the patient is discharged from the hospital or a maximum of 10 days (the event that occurs first). Approximately 500 devices in 80 injured extremities is planned to be used in this clinical study.
The primary objective is to compare CO2-levels in the replanted extremity in individuals who has undergone extremity replantation surgery and investigate if CO2-level is different in patient diagnosed with obstructed blood flow vs. patients with sufficient blood flow in the replanted extremity.
Our hypotheses are:
- The IscAlert™ device will be able to detect the presence of ischemia in the extremity replant by increased pCO2 levels and decrease in tissue temperature, measured by IscAlert™.
- By using the IscAlert™ device monitoring ischemic events, an early treatment for ischemia could lead to higher incidence of replantation survival rates, and less revision surgery caused by replantation thrombosis.
- No clinically significant bleeding or infection will occur using IscAlert™ in this clinical study.
- Conditions
- Ischemia, Blood Circulation Disorder, Carbon Dioxide, Biosensing Techniques, Amputation, Traumatic
- Being tested
- IscAlert
- Keywords
- Ischemia, Biosensor, Replantation, Carbon dioxide, Traumatic amputation, Orthopedic surgery, Limb
- Medical subject headings
- Ischemia, Amputation, Traumatic
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
IscAlertDevice
Insertion of a CO2- and temperature sensor in the distal part of the replanted extremity
| Study group | Role | What they receive |
|---|---|---|
| Patients with replanted extremity monitored by tissue CO2 | Experimental | Patients with traumatic amputation of a limb who are undergoing replantation surgery and are monitored postoperatively with IscAlert biosensor measuring local tissue CO2 and temperature in the replanted extremity Receives: Device: IscAlert |
What is being measured
The primary outcome is the main question the study is designed to answer.
Tissue CO2-level
Tissue CO2-level (kPa) during insertion period
Measured: 10 days
Secondary outcomes (5)
Bleeding
Amount of blood from insertion site (ml)
Measured: 10 days
Infection
Infection from insertion site at the discretion of the investigator (yes or no)
Measured: 30 days
Length of stay at hospital
Number of days from end of initial operation to primary hospital discharge + Number of days from transfer from primary hospital to discharge from secondary hospital.
Measured: 30 days
Time to reduced blood flow in replanted extremity
Number of days and hours from primary replant surgery end to obstructed blood flow is diagnosed.
Measured: 10 days
Number of re-operations
Number of reoperations caused by replant necrosis/ischemia in the replanted extremity
Measured: 30 days
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted28 Mar 2022
- Study start15 Nov 2022
- Primary completion30 Jun 2025
- Study completion30 Sep 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for IschemiaStudies of the same condition, open and under way.
- More trials run by Oslo University HospitalThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Diagnosis
- Allocation
- Not applicable
- Intervention model
- Single group
- Model description
- Prospective, interventional. Sixty patients (80 injured extremities) will receive tissue CO2 monitoring in the replanted extremity after traumatic amputation replant surgery.
- Masking
- None (open label)
- Enrolment
- 60 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Oslo University Hospital
- Sponsor type
- University, hospital or other
- Collaborators
- Sensocure AS
- Responsible party
- Principal investigator, Magne Røkkum, Oslo University Hospital
- Investigators
- Magne Røkkum, MD, Ph.D, Principal investigator, Oslo University Hospital
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05297266
- Sponsor's protocol ID
- REK SØR-ØST B, ref 340841
- Acronym
- EDIR
- Status last verified
- Apr 2026
- First submitted
- 17 Mar 2022
- Last updated
- 28 Apr 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: No plan to share IPD to other researchers
Study at a glance
From the registry record, last updated by the sponsor on 28 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Early Discovery of Ischemia After Replantation Surgery of the Extremities (EDIR-study) ; An Open, Prospective, Intervention Study
- ClinicalTrials.gov ID
- NCT05297266
- Acronym / sponsor ID
- EDIR / REK SØR-ØST B, ref 340841
- Conditions
- Ischemia, Blood Circulation Disorder, Carbon Dioxide, Biosensing Techniques, Amputation, Traumatic
- Keywords
- Ischemia, Biosensor, Replantation, Carbon dioxide, Traumatic amputation, Orthopedic surgery, Limb
- Study type
- Interventional
- Recruitment status
- Active, not recruiting
- Enrolment
- 60 participants (estimated)
- Lead sponsor
- Oslo University HospitalUniversity, hospital or other
- Collaborators
- Sensocure AS
- Study start
- 15 Nov 2022 (actual)
- Primary completion
- 30 Jun 2025 (actual)
- Study completion
- 30 Sep 2027 (estimated)
- First posted
- 28 Mar 2022 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Investigators will test if changes in CO2 is detected postoperatively in ischemic tissue in a replanted extremity of a traumatically amputated upper or lower extremity. IscAlert is measuring continuously CO2 in muscular and subcutaneous tissue. IscAlert is inserted distal to the operative field into normal muscle and/or subcutaneous tissue in the replanted extremity. Local tissue CO2 and temperature will be monitored continuously postoperatively for the next 10 days. If a reduced or totally obstructed blood flow appear (thrombosis), an increase in tissue CO2 and a lower local temperature will emerge rapidly as a sign of ischemia. This will be detected by the sensor which will alarm the investigators. This will lead to assessment of the replanted extremity and if restricted blood flow is diagnosed, a reoperation will be performed. After reoperation new sensors will be implanted for another ten days if applicable. Sixty patients will be enrolled to undergo the procedures. The IscAlert will be removed from the patient before the patient is discharged from the hospital or a maximum of 10 days (the event that occurs first). 500 devices is planned to be used in this clinical study.
Detailed description
This is an open, prospective, interventional, single-center clinical investigation designed to examine the feasibility and safety of the IscAlert™ device in patients scheduled for extremity replant surgery. Sixty patients will be enrolled to undergo the procedures using a total of 400 devices depending on the injuries.
IscAlert is 0.8 mm in diameter and in vitro testing, shows stable and accurate measurements of pCO2. More than 200 animal experiments have been done with the sensor. The experiments have shown that the sensor detects ischemia (Increased CO2-measurements) in real time in the following organs and tissues: Brain, heart, liver, kidneys, pancreas, intestines, musculature and subcutaneous tissue. Sensitivity and specificity are close to 100%. The sensors are inserted into tissue by a split needle technique. The split needle is the size of a 3-gauge peripheral venous catheter. In animal studies, no complications have been detected when using the sensor.
The IscAlert catheters are connected to an electronics unit that is fixed to the skin with an adhesive plaster or glue outside the sterile area. The electrical signals are redirected to a PC approved for clinical use which continuously records tissue pressures of CO2.
IscAlert is inserted into normal muscle and/or subcutaneous tissue distal on the replanted limb to be operated at the end of surgery or immediate postoperatively. The insertion is far away from the operating field. The insertion is done under sterile conditions in accordance with standard sterility criteria at the hospital. No pain during insertion will occur because of insertion is performed during anesthesia (general or regional). Also, the insertion can be compared to an intramuscular injection.
Postoperatively, the IscAlert sensor will continuously monitoring tissue CO2 and temperature. If ischemia occur, for examples caused by a thrombus, an increase in tissue CO2 and a lower temperature will evolve. This will be detected by the sensor which will alarm the investigators. This will lead to assessment of the replanted extremity and if restricted blood flow is diagnosed or suspected, a reoperation will be performed.
Sixty patients will be enrolled to undergo the procedures. The IscAlert will be removed from the patient before the patient is discharged from the hospital or a maximum of 10 days (the event that occurs first). Approximately 500 devices in 80 injured extremities is planned to be used in this clinical study.
The primary objective is to compare CO2-levels in the replanted extremity in individuals who has undergone extremity replantation surgery and investigate if CO2-level is different in patient diagnosed with obstructed blood flow vs. patients with sufficient blood flow in the replanted extremity.
Our hypotheses are:
- The IscAlert™ device will be able to detect the presence of ischemia in the extremity replant by increased pCO2 levels and decrease in tissue temperature, measured by IscAlert™.
- By using the IscAlert™ device monitoring ischemic events, an early treatment for ischemia could lead to higher incidence of replantation survival rates, and less revision surgery caused by replantation thrombosis.
- No clinically significant bleeding or infection will occur using IscAlert™ in this clinical study.
Study design
- Primary purpose
- Diagnosis
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
- Model description
- Prospective, interventional. Sixty patients (80 injured extremities) will receive tissue CO2 monitoring in the replanted extremity after traumatic amputation replant surgery.
| Arm | Type | Receives |
|---|---|---|
| Patients with replanted extremity monitored by tissue CO2 | Experimental | Device: IscAlertPatients with traumatic amputation of a limb who are undergoing replantation surgery and are monitored postoperatively with IscAlert biosensor measuring local tissue CO2 and temperature in the replanted extremity |
Who may qualify
- Ages
- 18 to 100 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (3 listed)
- Patients must be in need of extremity replantation surgery
- Subject must be ≥ 18 years
- Able to give written signed informed consent
Key exclusion criteria (1 listed)
- None
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| IscAlertInsertion of a CO2- and temperature sensor in the distal part of the replanted extremity | Device | Patients with replanted extremity monitored by tissue CO2 |
Primary outcome
Tissue CO2-level
Time frame: 10 days
Tissue CO2-level (kPa) during insertion period
5 secondary outcomes
Bleeding
Time frame: 10 days
Infection
Time frame: 30 days
Length of stay at hospital
Time frame: 30 days
Time to reduced blood flow in replanted extremity
Time frame: 10 days
Number of re-operations
Time frame: 30 days
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 28 Apr 2026.
- Individual participant dataSharing planned: No. No plan to share IPD to other researchers
Related trials for Ischemia
Active, not recruiting
The OCTOBER Trial - European Trial on Optical Coherence Tomography Optimized Bifurcation Event Reduction (OCTOBER)
Ischaemic Heart Disease, Ischemic Heart Disease
Not yet recruiting
New Biomarkers for Organ Viability Assessment During Hypothermic Machine Perfusion in Liver Transplantation: the Role of Extemporaneous Histological Examination.
Liver Transplantation (LT), Early Allograft Dysfunction
Not yet recruitingPhase 3
TicAgreLor Versus Placebo to Prevent Cerebral ISCHemia in anEuRysmal Low Grade SAH A Double Blinded Randomised Controlled Study
Subarachnoid Hemorrhage, Aneurysmal, Brain Ischemia
Recruiting
Randomized Prospective Trial on the Cost-Effectiveness of Photon-Counting CT Versus Energy-Integrating Detector CT in Suspected Chronic Coronary Syndrome
Computed Tomography Angiography, Coronary Artery Disease
Not yet recruitingObservational study
The GEIR (Grupo español de Ictus Retina) Registry: Rationale and Design of the First Nationwide Multicentre Retinal Stroke Registry in Spain
Retinal Artery Occlusion, Central Retinal Artery Occlusion
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Magne Røkkum, MD, Ph.D principal investigator
Oslo University Hospital
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing IscAlert in people with Ischemia and Blood Circulation Disorder, run by Oslo University Hospital at 1 site in Norway.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 1 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: under way, not looking for participants, as of the sponsor's last update on 28 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Norway. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Tissue CO2-level (time frame: 10 days). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 28 Apr 2026; AzTrials last refreshed its copy on 8 Nov 2026.