Postoperative analgesia for hepatic cryosurgery

Background : Hepatic cryosurgery is an alternative therapeutic choice for patients who are not eligible for surgical liver resection. As this procedure sometimes causes postoperative bleeding tendency, we investigated indication of intravenous patient-controlled analgesia (IVPCA) after this surgery. Methods : We measured pre- and postoperative platelet counts, coagulation profile and postoperative pain with IVPCA in 8 patients. Results : Platelet counts decreased from 9.83±5.38 (×10³ · ml^-1) to 5.91±4.56 (×10³ · ml^-1) postoperatively (P<0.01) and the maximum relative decrease was 72%. Platelet counts reached the maximum depression from 1 to 3 POD and in two patients it did not recover by 7 POD. Percentage of prothrombin activity decreased from 79.5±10.4 to 65.9±13.2 (P<0.01), with the nadir observed from 0 POD to 2 POD. In this study it was difficult to predict the extent of postoperative bleeding tendency beforehand. IVPCA with morphine provided adequate analgesia at rest. Althogh pain on moving seemed rather difficult to treat in two patients, IVPCA also helped patients walk with VAS score less than 55 mm in other patients. Conclusions : Considering the risk of bleeding tendency and epidural hematoma, we recommend IVPCA with opioid for postoperative pain in patients after hepatic cryosurgery instead of epidural analgesia and non-steroidal anti-inflammatory drugs.