小児用ネフロスコープの各種アクセスシースにおける流出パターンの生体内評価

To evaluate the outflow of the sheath of pediatric nephroscope with access sheath of various sizes in the boundaries of a standardized in vivo experimental set-up. Two female porcines of 10 kg each were used in this experiment. The experiment was performed with the use of a 7.5Fr Pediatric Nephroscope and two different access sheaths; 8.5/9.5Fr and 11/12Fr. The measurements of outflow were performed with the use of gravity irrigation and manual pump irrigation. Additionally, the presence of accessory instruments in the working channel was evaluated. Using the 8.5/9.5Fr access sheath, the outflow with gravity irrigation was estimated at 12.3±1.3 ml/min, while under manual pump irrigation conditions, the outflow was calculated at 13.9±1.6 ml/min. The presence of Laser Fiber in the working channel diminished the outflow to 10.05±1.85 ml/min and 12.4±1.9 ml/min with the use of gravity and manual pump irrigation, respectively. Moreover, the outflow was estimated at 5.05±1.5 ml/min and 5.8±1.4 ml/min with the utilization of gravity and manual pump irrigation, respectively, when the basket was inserted into the working channel. The outcomes were ameliorated with the use of 11/12Fr access sheath. Both access sheaths used in this experimental study presented adequate outflow, even when the working channel was used for the introduction of instruments. Although no monitoring of IRP and temperature was performed in our experiment the outflow values we recorded probably correspond to safe changes in IRP and temperature.