IschemiaISCALERTNCT04893473
New Method for Real-time Detection of Tissue Ischemia
An observational study of Ischemia and Blood Circulation Disorder, run by Oslo University Hospital at 1 site in Norway.
Trial summary
This is a prospective, single arm, open, single centre clinical investigation designed to examine the feasibility and safety of the IscAlert™ device in patients scheduled for limb (arm/leg) surgery with tourniquet. IscAlert is measuring carbon dioxide 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
- How many people
- 0 participants
- Where
- 1 siteNorway
- Study dates
- 14 May 2021to 14 May 2021
- Phase
- Observational
- Are there results?
- None posted in the registry
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
Study population: Patients who need limb surgery with tourniquet cuff
Who may be able to join
- Patients must be scheduled for orthopedic limb surgery with planned use of tourniquet.
- Subject must be ≥ 18 years
- Able to give written signed informed consent
- Tourniquet planned to be used > 30 minutes
Who cannot join
- Sign of inflammation/infection, hematoma, and traumatized tissue at insertion site
- Chronic use of anticoagulants
Trial locations and contacts
1 site in 1 country.
About this study
Official title: New Method for Real-time Detection of Tissue Ischemia; IscAlert™ - Study
This is a prospective, single arm, open, single centre clinical investigation designed to examine the feasibility and safety of the IscAlert™ device in patients scheduled for limb (arm/leg) surgery with tourniquet. IscAlert is measuring carbon dioxide in muscular and subcutaneous tissue. IscAlert is inserted into normal muscle and subcutaneous tissue in ischemic (operated limb with a tourniquet) and non-ischemic limb (non-operated limb).After the tourniquet is inflated, ischemia develops in the muscles and subcutaneous tissue. This will result in an increase in carbon dioxide, which will be detected by the sensor on the operated extremity, while the sensor on the non-operated will show normal values. After releasing the tourniquet cuff, the muscle will be reperfused and the carbon dioxide level is expected to decrease into normal levels. 50 number of patients will be enrolled to undergo the procedures. The IscAlert will be removed from the patient before the patient is discharged from the operating room, but in 25 of the patients, IscAlert™ will be inserted for 72 hours in the operated extremity after the end of surgery. After this, the sensors are removed.250 Devices is planned to be used in this clinical study.
Read the detailed description
This is a prospective, single arm, open, single centre clinical investigation designed to examine the feasibility and safety of the IscAlert™ device in patients scheduled for limb (arm/leg) surgery with tourniquet.
50 number of patients will be enrolled to undergo the procedures detailed in this clinical investigational plan using 250 devices.
IscAlert is 0.8 mm in diameter and in vitro testing, shows stable and accurate measurements of tissue carbon dioxide . More than 100 animal experiments have been done with the sensor. The experiments have shown that the sensor detects ischemia (Increased carbon dioxide-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 outside the sterile area. The electrical signals are redirected to a personal computer approved for clinical use which continuously records tissue pressures of carbon dioxide .
IscAlert is inserted into normal muscle and subcutaneous tissue proximal on the limb to be operated. The insertion is distal to the blood cuff, and far away from the surgery 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 after anesthesia induction. Also, the insertion can be compared to an intramuscular injection.
An identical IscAlert catheter is also inserted in the opposite extremity that is not to be operated and serves as a reference value. After the tourniquet is inflated, ischemia develops in the muscles and subcutaneous tissue. This will result in an increase in carbon dioxide, which will be detected by the sensor on the operated extremity, while the sensor on the non-operated will show normal values.
After releasing the tourniquet cuff, the muscle will be reperfused and the carbon dioxide level is expected to decrease into normal levels within 15 - 45 minutes. In 25 patients, the biosensors will be removed from the patient before the patient is discharged from the operating room, but in 25 of the patients, IscAlert will be inserted for 72 hours in the operated extremity after the end of surgery to identify drifting of the sensors. After this, the sensors are removed.
The primary objective is to evaluate the ability of the IscAlert device to measure carbon dioxide levels in ischemic and non-ischemic limb musculature and subcutaneous tissue in patients who experience orthopedic surgery with limb tourniquet and to assess the safety/efficacy using device IscAlert.
Our hypotheses are:
- The IscAlert device will be able to detect the presence of ischemia in muscle and subcutaneous tissue, whereby carbon dioxide levels, measured by IscAlert, will be higher in ischemic musculature than non-ischemic musculature in patients undergoing orthopedic limb surgery.
- No clinically significant bleeding or infection will occur using IscAlert in this clinical study.
- Being tested
- IscAlert
- Keywords
- Ischemia, Carbon dioxide, Biosensor, Musculature, Subcutaneous, Surgery, Orthopedic, Limb
- Medical subject headings
- Ischemia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
IscAlertDevice
3 IscAlert sensors in the limb undergoing surgery and two control sensors in the opposite limb are inserted and carbon dioxide is measured continuously.
| Study group | Role | What they receive |
|---|---|---|
| Group 1 | Patients scheduled for limb (arm/leg) surgery with tourniquet where IscAlert is removed immediately after surgery.
All patients will receive 3 sensors in the limb undergoing surgery and two control sensors in the opposite limb. The sensor in the opposite extremity which is not to be operated serves as a reference value for carbon dioxide. Receives: Device: IscAlert | |
| Group 2 | Patients scheduled for limb (arm/leg) surgery with tourniquet where IscAlert is removed 72 hours after surgery.
All patients will receive 3 sensors in the limb undergoing surgery and two control sensors in the opposite limb. The sensor in the opposite extremity which is not to be operated serves as a reference value for carbon dioxide. Receives: Device: IscAlert |
What is being measured
The primary outcome is the main question the study is designed to answer.
Tissue carbon dioxide level
Tissue carbon dioxide level (kPa) during insertion period
Measured: 72 hours
Secondary outcomes (8)
Bleeding
Amount of blood from insertion site (ml)
Measured: 72 hours
Infection
Infection from insertion site at the discretion of the investigator (yes or no)
Measured: 1 week
Arterial carbon dioxide level
Blood gass analysis of carbon dioxide during surgery (kPa)
Measured: 2 hours
Arterial lactate level
Blood gass analysis of lactate during surgery (mmol/L)
Measured: 2 hours
Arterial pH level
Blood gass analysis of pH during surgery
Measured: 2 hours
Arterial Oxygen level
Blood gass analysis of Oxygen during surgery (Kpa)
Measured: 2 hours
Time of tourniquet
Minutes of inflated tourniquet during surgery (minutes)
Measured: 2 hours
End-tidal level of carbon dioxide
End-tidal level of carbon dioxide during anesthesia (kPa)
Measured: 2 hours
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted19 May 2021
- Study start14 May 2021 (estimated)
- Primary completion14 May 2021
- Study completion14 May 2021
Why it stopped: Send in by another researcher. This is terminated to avoid two identical studies
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
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 0 participants (actual)
Sponsor and investigators
- Lead sponsor
- Oslo University Hospital
- Sponsor type
- University, hospital or other
- Collaborators
- European Commission
- Responsible party
- Principal investigator, Espen Lindholm, Oslo University Hospital
- Investigators
- Magne Røkkum, Md, Ph.d, Principal investigator, Oslo University Hospital
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04893473
- Sponsor's protocol ID
- 1-20
- Acronym
- ISCALERT
- Status last verified
- May 2021
- First submitted
- 10 Aug 2020
- Last updated
- 24 May 2021
- 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 24 May 2021. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- New Method for Real-time Detection of Tissue Ischemia; IscAlert™ - Study
- ClinicalTrials.gov ID
- NCT04893473
- Acronym / sponsor ID
- ISCALERT / 1-20
- Keywords
- Ischemia, Carbon dioxide, Biosensor, Musculature, Subcutaneous, Surgery, Orthopedic, Limb
- Study type
- Observational
- Recruitment status
- WithdrawnReason stopped: Send in by another researcher. This is terminated to avoid two identical studies
- Enrolment
- 0 participants (actual)
- Lead sponsor
- Oslo University HospitalUniversity, hospital or other
- Collaborators
- European Commission
- Study start
- 14 May 2021 (estimated)
- Primary completion
- 14 May 2021 (actual)
- Study completion
- 14 May 2021 (actual)
- First posted
- 19 May 2021 (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.
This is a prospective, single arm, open, single centre clinical investigation designed to examine the feasibility and safety of the IscAlert™ device in patients scheduled for limb (arm/leg) surgery with tourniquet. IscAlert is measuring carbon dioxide in muscular and subcutaneous tissue. IscAlert is inserted into normal muscle and subcutaneous tissue in ischemic (operated limb with a tourniquet) and non-ischemic limb (non-operated limb).After the tourniquet is inflated, ischemia develops in the muscles and subcutaneous tissue. This will result in an increase in carbon dioxide, which will be detected by the sensor on the operated extremity, while the sensor on the non-operated will show normal values. After releasing the tourniquet cuff, the muscle will be reperfused and the carbon dioxide level is expected to decrease into normal levels. 50 number of patients will be enrolled to undergo the procedures. The IscAlert will be removed from the patient before the patient is discharged from the operating room, but in 25 of the patients, IscAlert™ will be inserted for 72 hours in the operated extremity after the end of surgery. After this, the sensors are removed.250 Devices is planned to be used in this clinical study.
Detailed description
This is a prospective, single arm, open, single centre clinical investigation designed to examine the feasibility and safety of the IscAlert™ device in patients scheduled for limb (arm/leg) surgery with tourniquet.
50 number of patients will be enrolled to undergo the procedures detailed in this clinical investigational plan using 250 devices.
IscAlert is 0.8 mm in diameter and in vitro testing, shows stable and accurate measurements of tissue carbon dioxide . More than 100 animal experiments have been done with the sensor. The experiments have shown that the sensor detects ischemia (Increased carbon dioxide-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 outside the sterile area. The electrical signals are redirected to a personal computer approved for clinical use which continuously records tissue pressures of carbon dioxide .
IscAlert is inserted into normal muscle and subcutaneous tissue proximal on the limb to be operated. The insertion is distal to the blood cuff, and far away from the surgery 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 after anesthesia induction. Also, the insertion can be compared to an intramuscular injection.
An identical IscAlert catheter is also inserted in the opposite extremity that is not to be operated and serves as a reference value. After the tourniquet is inflated, ischemia develops in the muscles and subcutaneous tissue. This will result in an increase in carbon dioxide, which will be detected by the sensor on the operated extremity, while the sensor on the non-operated will show normal values.
After releasing the tourniquet cuff, the muscle will be reperfused and the carbon dioxide level is expected to decrease into normal levels within 15 - 45 minutes. In 25 patients, the biosensors will be removed from the patient before the patient is discharged from the operating room, but in 25 of the patients, IscAlert will be inserted for 72 hours in the operated extremity after the end of surgery to identify drifting of the sensors. After this, the sensors are removed.
The primary objective is to evaluate the ability of the IscAlert device to measure carbon dioxide levels in ischemic and non-ischemic limb musculature and subcutaneous tissue in patients who experience orthopedic surgery with limb tourniquet and to assess the safety/efficacy using device IscAlert.
Our hypotheses are:
- The IscAlert device will be able to detect the presence of ischemia in muscle and subcutaneous tissue, whereby carbon dioxide levels, measured by IscAlert, will be higher in ischemic musculature than non-ischemic musculature in patients undergoing orthopedic limb surgery.
- No clinically significant bleeding or infection will occur using IscAlert in this clinical study.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Group 1 | – | Device: IscAlertPatients scheduled for limb (arm/leg) surgery with tourniquet where IscAlert is removed immediately after surgery. All patients will receive 3 sensors in the limb undergoing surgery and two control sensors in the opposite limb. The sensor in the opposite extremity which is not to be operated serves as a reference value for carbon dioxide. |
| Group 2 | – | Device: IscAlertPatients scheduled for limb (arm/leg) surgery with tourniquet where IscAlert is removed 72 hours after surgery. All patients will receive 3 sensors in the limb undergoing surgery and two control sensors in the opposite limb. The sensor in the opposite extremity which is not to be operated serves as a reference value for carbon dioxide. |
Who may qualify
- Ages
- 18 to 100 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Patients who need limb surgery with tourniquet cuff
Key inclusion criteria (4 listed)
- Patients must be scheduled for orthopedic limb surgery with planned use of tourniquet.
- Subject must be ≥ 18 years
- Able to give written signed informed consent
- Tourniquet planned to be used > 30 minutes
Key exclusion criteria (2 listed)
- Sign of inflammation/infection, hematoma, and traumatized tissue at insertion site
- Chronic use of anticoagulants
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 |
|---|---|---|
| IscAlert3 IscAlert sensors in the limb undergoing surgery and two control sensors in the opposite limb are inserted and carbon dioxide is measured continuously. | Device | Group 1, Group 2 |
Primary outcome
Tissue carbon dioxide level
Time frame: 72 hours
Tissue carbon dioxide level (kPa) during insertion period
8 secondary outcomes
Bleeding
Time frame: 72 hours
Infection
Time frame: 1 week
Arterial carbon dioxide level
Time frame: 2 hours
Arterial lactate level
Time frame: 2 hours
Arterial pH level
Time frame: 2 hours
Arterial Oxygen level
Time frame: 2 hours
Time of tourniquet
Time frame: 2 hours
End-tidal level of carbon dioxide
Time frame: 2 hours
Results and safety
The study was withdrawn before enrolling participants, so there are no results.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 24 May 2021.
- Individual participant dataSharing planned: No. No plan to share IPD to other researchers
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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?
An observational study of 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 4 inclusion and 2 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: withdrawn, as of the sponsor's last update on 24 May 2021. 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?
The study was withdrawn before enrolling participants, so there are no results.
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 carbon dioxide level (time frame: 72 hours). 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 24 May 2021; AzTrials last refreshed its copy on 1 Nov 2026.