デジタル吊秤による白内障手術時の眼灌流液の使用量測定

Monitoring of irrigating solution during cataract surgery using an elctronic hanging scale

白内障手術中の灌流液の重量の変化をデジタル吊秤で測定した。手術開始時に秤の目盛を0に設定し，以後は透明な袋に入った灌流液の重量をマイナスで表示させた。重量を密度1.00662g/mlで割った値を使用した灌流液の容積とした。白内障手術を行った234眼での灌流液使用量の平均は，超音波乳化吸引時104ml，灌流・吸引時45ml，手術全体で149mlであった。核硬度が上がると超音波乳化吸引時の使用量が増加したが，灌流・吸引時の値には差がなかった。この方法による灌流液の測定は，一般の点滴にも応用が可能である。

We devised a method to monitor the volume of irrigating solution during cataract surgery by means of elctronic hanging scale. The indicator of the scale was set at zero at the start of surgery. During surgery,the weight of irrigating solution contained in a tranparent bag was shown in minus units. The actually used volume of irrigating solution was calculated as weight divided by density,1.00662 g/ml. In 234 cataract surgeries,the volume of irrigating solution averaged 104 ml during phacoemulsification-aspiration（PEA）and 45 ml during irrigation-aspiration,totalling 149 ml. Eyes with hard nucleus needed greater amount of irrigating solution during PEA but not during irrigation-aspiration. The present method can also be applied to intravenous drip infusion.