The use of an infusion pump in arthroscopy

The use of an infusion pump is an effective method of irrigating the joint in arthroscopy. A Sarns roller blood pump is used to pump fluid into the joint through the arthroscope with outflow by gravity drainage through a plastic cannula. Flow and pressure can be adjusted independently. Measurements were made of calf, knee, and thigh swelling after arthroscopy in 42 patients; the average swelling of each was less than 1 cm. In 45 patients, the average rate of flow through the joint was 45 mm/min, with a measured outflow of 40 mm/min. Intraarticular pressure greater than 200 mm Hg can be obtained with the pump, compared with maximum pressures only slightly greater than 100 mm Hg with gravity inflow alone. The operator must carefully monitor the system; retention of excessive fluid can lead to postoperative swelling and morbidity.