Complication After Interpleural Analgesia

Abstract

To the Editor: We report an unusual complication after interpleural analgesia. A 76-yr-old male patient was scheduled for a left ureteronephrectomy because of ureter carcinoma. General anesthesia was induced with thiopental, fentanyl, and atracurium and maintained with midazolam, fentanyl, atracurium, and low concentrations of isoflurane in air. At the end of the procedure, while the patient was still in the semilateral position, an interpleural catheter was introduced on the midaxillary line at the level of the fourth intercostal interspace. Subsequently, a bolus of 10 mL 0.5% bupivacaine with 1:200,000 adrenaline was injected. The trachea was eventually extubated, and the patient transferred to the recovery room. The recovery room nurse was instructed to connect the interpleural catheter to a pump that was to deliver plain 0.25% bupivacaine at a rate of 6 mL/h. The nurse prepared a 50-mL plastic syringe with 0.25% bupivacaine and connected it to the interpleural catheter. At this point, she was urgently called by another patient, so she just put the syringe on the patient's bed without fixing it within the driving pump. When she came back 10 min later, she was struck by the fact that the syringe now contained only 10 mL. Checks were made, and it turned out that nobody had touched the syringe. The most likely explanation is that the syringe was emptied due to the negative interpleural pressure generated by the patient's breathing. Our patient was not affected by the two bupivacaine boluses (150 mg in 20 min) and made an uneventful recovery. N. Milliet, MD W. Studer, MD Department of Anesthesia Kantonsspital Basel, Switzerland