There are seven critical but often neglected factors that negatively affect the administration of CT contrast, according to an educational review published on 28 August in Insights into Imaging.
How IV contrast media is delivered is definitely a source of CT imaging variability, and uncovering hidden factors that contribute to this variability is key to improving patient care, wrote a team led by Michael C. McDermott, PhD, of Maastricht University Medical Center in the Netherlands.
"There remain several critical, but not commonly known, sources of error associated with contrast-medium injections," the group noted. "Elimination of these hidden sources of error where possible can bring immediate benefits and help to drive standardized and optimized contrast-media injections."
How IV contrast media is administered is a rarely considered source of CT imaging variability, McDermott and colleagues wrote, noting that previous research on CT contrast administration has focused on scan acquisition parameters (tube voltage, tube current), patient-related factors (body weight, cardiac output), and variations in contrast injection protocols (flow rate, volume, concentration).
But there are variables that are often not considered that affect contrast administration, they explained, offering the following list:
- The selection of optimal IV catheters
- Degraded contrast performance due to longer tubing sets
- Variability associated with the mechanical injection system technology
- Operator errors (such as incorrect filling of syringes or reservoirs)
- Unwanted exchange of fluids (i.e., contrast trades places with saline) due to gravity and density
- Wasted contrast media and inefficient saline flushes
- Departure from the programmed injection flow rate
To eliminate suboptimal CT contrast administration, McDermott and colleagues suggested that radiology departments evaluate the gravity flow rate of the catheters being used; switch to shorter tubing sets; and assess the "value chain" of contrast-enhanced exams, from the injection system and operator skill to exam setup procedures.
In any case, becoming aware of these less commonly known factors and addressing them leads to better patient care, quality improvements, and financial benefits, according to the group.
When contrast enhancement is unexpectedly suboptimal, we often blame intrinsic patient factors or are just puzzled without knowing what to do," the team wrote. "Understanding these critical but commonly neglected technical factors is an opportunity for wider awareness and correction where possible."
The complete study can be found here.
