Venous Thromboembolism
Conditions
Keywords
low molecular weight heparin, enoxaparin, Lovenox, Insuflon, subcutaneous catheter, once or twice daily dosing of subcutaneous enoxaparin
Brief summary
The purpose of this study is to ascertain whether subcutaneous ports are an effective and reliable way to administer the low molecular weight heparin (LMWH) enoxaparin to patients for the prevention or treatment of venous thromboembolism.
Detailed description
Subcutaneous ports have recently been used to administer Low Molecular Weight Heparin (LMWH) to patients for the prevention or treatment of venous thromboembolism; however, no studies have been performed to evaluate the ports' reliability in delivering this type of drug. Hence, it is not known whether absorption of the drug is constant over the seven-day lifespan of the port. Although the use of subcutaneous ports is not currently the standard of care, health care providers are more frequently using this as an alternative method to direct injection of LMWH, particularly in pediatric patients. The main advantage of subcutaneous ports is the decreased number of needle sticks when using the ports to administer the medication. However, it is possible that, due to potential repeated bleeding into the subcutaneous space at the port site or other factors, drug absorption may decrease over the seven day lifespan of the port, resulting in a decrease of plasma drug level. Subtherapeutic LMWH levels and, hence, ineffective anticoagulation may result. This study's aim is to determine if the current use of subcutaneous ports is a safe, effective and reliable way of administering LMWH for the purpose of anticoagulation.
Interventions
DEVICEInsuflon
Indwelling subcutaneous catheter indicated for subcutaneous infusion of medication by injection. Maximum lifespan: 7 days or 75 injections.
Sponsors
IntraPump Infusion Systems
Laboratory Corporation of America
University of North Carolina, Chapel Hill
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
SUPPORTIVE_CARE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Subjects receiving once or twice daily dosing of therapeutic doses of subcutaneous Enoxaparin. * Subject has been on the same dose of Enoxaparin for at least one week. * Anticipated length of Enoxaparin treatment at least 4 weeks. * Age ≥ 18 years. * Subject demonstration of proper subcutaneous catheter care during one education session with the investigator.
Exclusion criteria
* Chronic renal insufficiency with glomerular filtration rate \< 30 mL/min. * Pregnancy * Venous thromboembolism within the last 4 weeks.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Average Subcutaneous Anti-Xa Blood Levels | approximately 3 months | Blood levels taken from the first and last visits (when available) were combined to get an average. The anti-Xa test reports the low molecular weight heparin concentration in the blood. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Percent Difference of Each Participant's Subcutaneous Anti-Xa Levels | 6 time points (for each participant) in approximately 3 months | Anti-Xa subcutaneous blood levels are displayed in percent difference to show normal fluctuations of anti-Xa levels without using the port. A percent difference is calculated by the current value has the previous value subtracted from it; this new number is divided by the absolute value of the previous value; then this new number is multiplied by 100. This allows each set of data to be compared to itself. Anti-Xa tests measure the concentration of low molecular weight heparin in the blood. |
| Percent Difference of Each Participant's Anti-Xa Levels Without Port and Day One of Using the Port | approximately 3 months | Comparing subcutaneous baseline (without port) anti-Xa levels with day one of using the port. A percent difference is calculated by the current value has the previous value subtracted from it; this new number is divided by the absolute value of the previous value; then this new number is multiplied by 100. This allows each set of data to be compared to itself. Anti-Xa tests measure the concentration of low molecular weight heparin in the blood. |
| Percent Difference of Each Participant's Anti-Xa Blood Levels Between Day 1 and Day 7 | 7 days | Comparing anti-Xa levels from the first day of using the port and the last day of using the port. A percent difference is calculated by the current value has the previous value subtracted from it; this new number is divided by the absolute value of the previous value; then this new number is multiplied by 100. This allows each set of data to be compared to itself. Anti-Xa tests measure the concentration of low molecular weight heparin in the blood. |
| Standard Deviation of Participant's Own Glomerular Filtration Rate (GFR) | 6 time points in approximately 3 months | GFR was calculated from a creatinine blood level to establish a safe renal function that would validate anti-Xa levels. Low molecular weight heparin is primarily cleared from the body by the kidneys. Any condition that decreases kidney function can potentially decrease LMWH clearance, increasing its concentration in the blood and increasing the potential for excessive bleeding. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Insuflon All participants in the study will use the subcutaneous catheter twice for a period of one week each to inject the enoxaparin. For the remainder of the study the participants will inject subcutaneously. | 21 |
| Total | 21 |
Withdrawals & dropouts
| Period | Reason | FG000 |
|---|---|---|
| Overall Study | Lost to Follow-up | 3 |
Baseline characteristics
| Characteristic | Insuflon |
|---|---|
| Age, Categorical <=18 years | 0 Participants |
| Age, Categorical >=65 years | 6 Participants |
| Age, Categorical Between 18 and 65 years | 15 Participants |
| Age, Continuous | 58.4 years STANDARD_DEVIATION 15.6 |
| Region of Enrollment United States | 21 participants |
| Sex: Female, Male Female | 15 Participants |
| Sex: Female, Male Male | 6 Participants |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | — / — |
| other Total, other adverse events | 1 / 21 |
| serious Total, serious adverse events | 0 / 21 |
Outcome results
Primary
Average Subcutaneous Anti-Xa Blood Levels
Blood levels taken from the first and last visits (when available) were combined to get an average. The anti-Xa test reports the low molecular weight heparin concentration in the blood.
Time frame: approximately 3 months
Population: Participants were separated into the two dosing schedules, since the target anti-Xa level is different for the two different types of doses. The once daily dosing sub-group was analyzed for this primary outcome measure.
| Arm | Measure | Value (MEAN) |
|---|---|---|
| All Participants | Average Subcutaneous Anti-Xa Blood Levels | 1.43 IU/mL |
Secondary
Percent Difference of Each Participant's Anti-Xa Blood Levels Between Day 1 and Day 7
Comparing anti-Xa levels from the first day of using the port and the last day of using the port. A percent difference is calculated by the current value has the previous value subtracted from it; this new number is divided by the absolute value of the previous value; then this new number is multiplied by 100. This allows each set of data to be compared to itself. Anti-Xa tests measure the concentration of low molecular weight heparin in the blood.
Time frame: 7 days
Population: All participants, excluding two outliers of 97% and 150%
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| All Participants | Percent Difference of Each Participant's Anti-Xa Blood Levels Between Day 1 and Day 7 | 16 Percent |
Secondary
Percent Difference of Each Participant's Anti-Xa Levels Without Port and Day One of Using the Port
Comparing subcutaneous baseline (without port) anti-Xa levels with day one of using the port. A percent difference is calculated by the current value has the previous value subtracted from it; this new number is divided by the absolute value of the previous value; then this new number is multiplied by 100. This allows each set of data to be compared to itself. Anti-Xa tests measure the concentration of low molecular weight heparin in the blood.
Time frame: approximately 3 months
Population: Twenty participants, excluding one outlier of 97%.
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| All Participants | Percent Difference of Each Participant's Anti-Xa Levels Without Port and Day One of Using the Port | 14 Percent |
Secondary
Percent Difference of Each Participant's Subcutaneous Anti-Xa Levels
Anti-Xa subcutaneous blood levels are displayed in percent difference to show normal fluctuations of anti-Xa levels without using the port. A percent difference is calculated by the current value has the previous value subtracted from it; this new number is divided by the absolute value of the previous value; then this new number is multiplied by 100. This allows each set of data to be compared to itself. Anti-Xa tests measure the concentration of low molecular weight heparin in the blood.
Time frame: 6 time points (for each participant) in approximately 3 months
Population: All participants were represented with a baseline fluctuation in percent difference.
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| All Participants | Percent Difference of Each Participant's Subcutaneous Anti-Xa Levels | 12 Percent |
Secondary
Standard Deviation of Participant's Own Glomerular Filtration Rate (GFR)
GFR was calculated from a creatinine blood level to establish a safe renal function that would validate anti-Xa levels. Low molecular weight heparin is primarily cleared from the body by the kidneys. Any condition that decreases kidney function can potentially decrease LMWH clearance, increasing its concentration in the blood and increasing the potential for excessive bleeding.
Time frame: 6 time points in approximately 3 months
Population: Included all participants who had at lease one visit and one blood draw.
| Arm | Measure | Value (MEAN) |
|---|---|---|
| All Participants | Standard Deviation of Participant's Own Glomerular Filtration Rate (GFR) | 6.75 mL/min |