Ries M D, Rauscher L A, Hoskins S, Lott D, Richman J A, Lynch F
Department of Orthopaedic Surgery, University of California, San Francisco Medical Center 94143, USA.
Clin Orthop Relat Res. 1998 Nov(356):154-60. doi: 10.1097/00003086-199811000-00022.
Twenty-eight patients who underwent unilateral total knee arthroplasty and 20 patients who underwent simultaneous bilateral total knee arthroplasties participated in this study and were randomized to have either a fluted or round 10-mm diameter femoral intramedullary alignment rod used during surgery. The intramedullary rods were cannulated and connected with pressure tubing to a monitor which provided measurements of pressure at the tip of each rod. Arterial blood gas measurements on room air were obtained before and on the morning after surgery. An arterial line was placed and an arterial blood gas measurement was obtained at the time of skin incision and again after tourniquet release. Pulmonary shunt was calculated from the arterial blood gas measurements. Intramedullary pressure during rod insertion was significantly higher for the groups of patients having the round compared with the fluted rod. The change in pulmonary shunt during surgery was lowest for the patients in the unilateral group having the fluted rod and highest for the patients in the bilateral group having the round rod. A fluted rather than a round intramedullary alignment rod should be used to minimize intramedullary pressure and pulmonary shunting during unilateral and bilateral total knee arthroplasties.
28例行单侧全膝关节置换术的患者和20例行同期双侧全膝关节置换术的患者参与了本研究，并被随机分为在手术中使用带槽或圆形直径10毫米股骨髓内定位杆两组。髓内杆为中空的，并通过压力管连接到一个监测器，该监测器可提供每根杆尖端的压力测量值。在手术前及术后早晨采集患者在室内空气中的动脉血气测量值。放置动脉导管，并在皮肤切开时及松开止血带后再次采集动脉血气测量值。根据动脉血气测量值计算肺分流。与带槽杆组相比，圆形杆组患者在插入杆时的髓内压力显著更高。手术期间，单侧组使用带槽杆的患者肺分流变化最小，双侧组使用圆形杆的患者肺分流变化最大。在单侧和双侧全膝关节置换术中，应使用带槽而非圆形的髓内定位杆，以尽量减少髓内压力和肺分流。
