注射器の内筒操作技術に関する研究

抄録

The objectives of the current research were to clarify differences in beginners' and nurses' techniques for manipulation of a syringe and to propose methods of education for mastering quick and accurate techniques. In this paper, differences in techniques for manipulation of a syringe by nursing students and nurses are discussed from two perspectives. One is the effects of combining the syringe and injection needle in terms of the pressure in the syringe. The other is differences in methods of grasping the syringe. Based on these results, problems relating to adjustment of the force used by a nurse to manipulate a syringe and contact of the fingertip with the plunger become apparent.
For measurement of the pressure in the syringe, a processed syringe is connected to a strain gauge type of force conversion device and strain is converted to pressure. For pressing of the plunger, hypodermic injection and extrusion of a drug solution into a vial were performed. For drawing of the plunger, collection of blood and suctioning from a plastic ampule were performed.
With regard to pressure in the syringe, the maximum gauge pressure was large for a finer injection needle when the syringe was the same size in all techniques for nursing students as well as nurses. In simulated hypodermic injection, nursing students had a larger maximum gauge pressure with a larger syringe with the same injection needle. However, nurses considered the effects on the body and adjusted force so that the maximum gauge pressure did not increase. Because extrusion from a syringe and suctioning from an ampule are techniques that do not insert a needle in the body, nurses added substantial force and manipulated the syringe in a short period of time. In addition, limits for the addition of force were also considered.
Based on classification of patterns of waveforms with regard to drawing of the plunger in suctioning from an ampule, nursing students often had multiple valley-shaped waveforms. Patterns produce waveforms like this because the syringe is passed from hand to hand. Differences in the appearance of waveforms due to the size of the syringe were noted for nurses, indicating separate use of methods of manipulating a syringe plunger as needed.
With regard to the grasping of a syringe, nursing students grasp it so as not place their fingertip in contact with the plunger. This is because they are taught in class not to make contact with the plunger based on the perspective of preventing infection. However, a majority of nurses make contact with the plunger when drawing the plunger. That is, making contact with the plunger for drawing of the plunger is a technique in which the plunger is easy to manipulate. Nurses may have adopted an efficient method in clinical settings. Even if the stance that contact with the plunger should be avoided to prevent infection is learned, making contact with the plunger as experience is acquired leads one to conclude that education in techniques for manipulation of injections is vague. Having nurses change the techniques they have acquired is difficult, so sterile gloves should be worn as a general rule when manipulating a syringe.
In the future, force added to the suction head of a syringe plunger will be measured and the relationship with internal pressure will be verified.