SECurement DEvice Testing
When trying to solve a problem, it's important to fully understand all the issues at hand. Correspondingly, we thought it was important to know the performance characteristics of some of the top selling adhesives and securement devices in order to reduce the number of IV failures that occur annually.
For the skin model, we took pig skin, shaved off the hair and clamped it down over a three-inch diameter PVC pipe that was cut in half to simulate a human arm. For the IV catheter model, we installed an IV catheter and secured it using four of the top selling adhesives according to their instructions for use. A constant force pulling at 1 meter/minute was applied from three different angles until the catheter failed. The pull was repeated seven times for each securement device from each of the three angles for a total of 21 pull tests per device. To the right is a video showing a sample of how the study was conducted.
The hand in each chart to the right shows the angle from which the pull occurred, the force at which the catheters had a loss of function (defined as pulling out of the skin 1 cm or torquing to an angle greater than 45 degrees is indicated by a circle), the point of initial dressing disruption (indicated by a square), and the point at which the catheter completely dislodged (indicated by the line dropping to zero). The information was averaged for the seven pulls and a chart produced for each angle of pull.
As was expected, the performance of the securement devices varied. The design of each device had a large impact on its performance. Some were easier to pull out from the side and others from the top, etc.
Consistently, forces slightly above 4 lbs led to either dressing disruption, loss of catheter function and with one securement, full dislodgement. Full dislodgement with the other securements tended to occur at forces greater than 8 lbs.
If forces above 4 lbs start to have undesired effects on the catheter/dressing and forces above 8 lbs dislodge the catheter, then what happens in-between? We theorize that the forces between 4 and 8 lbs are the ones that compromise the catheter, possibly causing phlebitis and/or infiltration.
We believe that some normal forces across an IV catheter are acceptable and occur with activities of daily living. There are clearly dangerous forces that lead to dislodgement of the IV catheter, and other forces can occur in the spectrum between normal and dangerous forces, which we call harmful forces. These zones of forces vary by securement design. We summarize all the previous charts into one final chart that shows the averages from all the pulls displayed in one straightforward graph below.