ベッドの高さの違いからみた移動援助時の患者の頚部筋負担及び看護師の作業効率への影響 The Difference of Nurse's Working Efficiency and the Influence to Patients Neck Muscle Loads in Patient Transfer at Different Heights of Beds

本研究では，ベッドの高さの違いによる看護師の作業効率の違いが患者の頚部筋負担に及ぼす影響を検証した．被験者（患者役）は健康高齢女性15名とし，1名の看護師役が患者役に，移動の援助を2つのベッドの高さ（易作業高：看護師役身長の49％，及び不易作業高：同32％）で実施した．異なるベッドの高さ間で，胸鎖乳突筋の積分筋電図，最大脊柱挙上角度，頚部後屈角度，援助の所要時間に有意差がみられた．これは不易作業高での援助時，看護師役が患者役の脊柱を挙上し，患者役の頚部がより後屈し，このような姿勢が安楽でないために患者役が無意識に顎を引き，頚部筋負担が増大したと考えられる．安楽でない姿勢を取る時間の延長も患者には負担であるといえる．看護師役の作業効率の低下は，患者役を動かすのに必要な分力の減少による所要時間の延長からわかる．つまり，不易作業高での援助時，看護師の作業効率は低下し，患者の頚部筋負担を増加させる．

This study examined the difference of nurses work efficiency by changing the height of beds, and how the difference of nurses working efficiency influences the patients neck muscle load. 15 healthy women over 70 years old participated in this experiment as the patient role. One researcher, assuming the nurse role, performed patient transfers in two different bed heights : easy and uneasy working height beds. When the bed was set to the uneasy working height, patients backbone was more lifted, and took more time to complete the transfer. These results show that nurses working efficiency is decreasing when patient transfer is performed at uneasy working height. Moreover, at the uneasy working height, patients neck hyperextension angle and integrated electromyogram of sternocleidomastoid muscles showed larger values than those of easy working height. The reason of this phenomenon is, as it is not comfortable lying with lifted backbones and retroflexed necks, patients attempted to draw in their chin unconsciously. Therefore, it can be said that, when patient transfer is performed at an uneasy working height, nurses working efficiency decreases and patients neck muscle load increases.