早産児の侵害受容性刺激に対する顔面表情運動の定量的検討

Computerized Quantitative Analysis of Facial Motion of Nociceptive Stimulus on Preterm Infants

はじめに

　新生児は，年長児や成人に比べ，痛みに対して敏感であり，その影響を長期的に受ける。特に，出生体重1000g未満で出生した早産児の場合，学童期に痛みを描いた絵をみた時の情緒的反応の程度はNICU入院期間に相関することが明らかにされている（Grunau，1998）。NICUにおける痛みのケアの重要性を示す結果である。

　痛みのケアにおいては予防が不可欠であるが，避けることができない痛みについては，痛み体験を的確にアセスメントし，鎮痛法を実施し，その効果を判定しなければならない。そのためには痛みを測定する方法が必要である。

　The purpose of this study was to analyze quantitatively facial motion of nociceptive stimulus on preterm infants for developing pain assessment tool. Subjects were seven preterm infants who met the inclusion criteria of being less than 32 weeks gestational age at birth and having no neurologic abnormalities, and whose parents gave consent. Data was collected at twenty sessions for routine procedures (heel stick, venipuncture). Each session had three phases (quiet, disinfection, stick/puncture). Facial motions were videotaped and analyzed quantitatively with computer, and heart rate and respiratory rate were observed with cardio-respiratory monitor.

　Results were as follows : 1) Six points on upper face were used for measurement of the most noticable facial motion of nociceptive stimulus and no significant difference was found for each of the two point distances, for all six points ; 2) the area of shape formed with four points was useful for analysis quantitatively of facial motion of nociceptive stimulus on preterm infants ; 3) Four points were as follows : right upper orbital, left upper orbital, midway between right upper orbital and left upper orbital, nasin ; 4) Heart rate and respiratory rate were not specific pain response because no significant difference was found between disinfection phase and stick/puncture phase.