[Continuous venous infusion of buprenorphine with autonomous elastomeric system in the control of postoperative pain]

We herein evaluated the analgesic effectiveness of low doses of buprenorphine with or without a primer and the practicality and usefulness of a constant flow disposable infusion set (Infusor Baxter 2 ml/h). Our series consists of 300 patients, seen between January 1992 and December 1993, randomly distributed in three groups of 100 patients each. All patients were informed before operation about the use of pain Visual Analogical Scale (VAS) and how the infusor works. At the end of the operation all patients had an infusor positioned with a 0.01 mg/kg supplied of buprenorphine diluted to 60 ml with Ringer's Lactate solution. In addition to this, group B patients received an i.v. primer of 0.003 mg/kg of buprenorphine diluted to 10 ml with saline solution and group C patients received an i.v. primer of 0.5 mg/kg of ketorolac diluted to 10 ml with saline solution. VAS, systolic arterial pressure, diastolic arterial pressure, heart rate, respiratory rate, request of analgesics and side effects were evaluated at one hour (T0), six hours (T1), 12 hours (T2), 24 hours (T3) and 36 hours (T4) after operation. Group B and C patients showed significant reduction in VAS compared to group A patients at T0 and T1 but the difference disappeared starting from T2. Group B and C patients showed blood pressure, heart rate and respiratory rate values significantly reduced compared to group A patients at T0 and T1. Such values however then stabilized. Side effects encountered were nausea and vomiting in different percentages in the three groups.(ABSTRACT TRUNCATED AT 250 WORDS)