2018 年 44 巻 1 号 p. 15-23
In the medical scene of drug administration via tubes, catheter-type syringes should be changed whenever sliding of the syringe plunger deteriorates. We encountered a situation where the syringe plunger sliding worsened earlier than other preparations. However, there have been no reports investigating factors that impair plunger sliding. In this report, we evaluated the grime on the plunger gasket in relationship to the force for sliding resistance of the plunger.
Prescription drugs studied included “Gaster® Tablets 20 mg” and other four drugs. The number of pixels on the image corresponded to the amount of grime. The force applied on the plunger was measured using a digital force gauge.
We observed a correlation, albeit weak (R = 0.51), between the number of pixels and the force required to move the plunger. The force and particle number values were high for “Gaster® Tablets 20 mg”. We repeated the measurements with “Gaster® D Tablets 20 mg”. Lower values were obtained for “Gaster® D tablets 20 mg”. Talc, showed higher values so that the smaller the particle sizes, the higher the contents. Conversely, low substituted hydroxypropylcellulose and anhydrous dibasic calcium phosphate, of the type present in “Gaster® Tablets 20 mg” as an additive, gave lower values.
In conclusion, the grime on gaskets is a sign that the syringes need to be changed, and the content and particle size of the talc, which was an additive agent, is one of the factors that impair syringe plunger sliding.
