Assessment of a new infusion pump for epidural PCA.

The use of epidural fentanyl by patient-controlled analgesia (PCA) may be a useful method of providing high-quality postoperative analgesia on the general surgical ward. The successful use of this technique requires an infusion pump with specific characteristics. Three Provider 5500, newly-developed, battery-powered PCA pumps, were tested to determine their accuracy, threshold of occlusion alarm limits and stored volume characteristics. These measurements were repeated following the in-line addition of an 18 gauge epidural catheter and two 0.2 micron filters. Pumps delivered on average within 3% of stated infusion rates and within 3% of bolus dose size. Occlusion pressures generated were between 1200 and 1360 mmHg, while the mean stored volume was 0.12 ml. Accuracy of delivery was maintained at lower voltage inputs. Addition of the catheter failed to alter the accuracy of the pumps tested. Siphoning of fluid was possible on disconnection of cartridge from pump. This problem did not occur with the addition of an epidural catheter and filter. This device has features which make it suitable for the safe delivery of epidural PCA. Care, however, needs to be taken on changing cartridges to prevent accidental administration of a drug bolus to the patient.