Transesophageal Echocardiography Monitored Embolic Events during the Total Knee Replacement: Hemodynamic Changes and Embolic Composition / 대한마취과학회지

BACKGROUND: The present study was aimed to determine the alterations of hemodynamics and embolic composition during the course of total knee replacement. METHODS: A retrospective analysis was performed using data acquired from 20 patients who underwent 10 unilateral and 10 bilateral total knee replacement under general anesthesia. Transesophageal echocardiography and Swan-Ganze catheterization were placed following induction of anesthesia, then images and changes were recorded throughout the procedure. All patients were performed using fluted intramedullary rods inserted into an overdrilled femoral entrance hole in conjunction with the application of a tourniquet. RESULTS: We found echogenic emboli in 8 out of 20 patients during cannulation of the femoral canal and performing femoral and tibial saw cuts, then we detected echogenic emboli in all 20 patients during tourniquet deflation. Echogenic emboli consistently filled the right atrium and ventricle with very small size embolic materials for 19 7 minutes during total knee replacement. Heart rate exhibited no change, Mean arterial pressure decreased and mean pulmonary artery pressure increased after tourniquet deflation. After tourniquet deflation, free fatty acid increased in lipid profile. No patient had postoperative complications related echogenic emboli. CONCLUSION: All patients exhibited echogenic emboli during certain stages of total knee replacement. Although all patients were asymtomatic in our study, one should be cautioned when performing total knee replacement in patients with little physiologic reserve and large embolic events.

Spinal Anesthesia Using 0.5% Hyperbaric Bupivacine/Fentanyl Mixture for Cesarean Section / 대한마취과학회지

BACKGROUND: The last two decades have seen an increase in the incidence of cesarean section. Spinal anesthesia has been popular in cesarean delivery because of the ease and effectiveness, as well as the rapidity in estabilishing adequate levels of analgesia. The clinical effects of subarachnoid administeration of preservative-free fentanyl were assessed in 30 healthy women who underwent cesarean section with spinal anesthesia using 0.5% hyperbaric bupivacaine. METHODS: Sixty parturients were allocated to group I; bupivacaine (n=30) only and group II; bupivacaine/fentanyl mixture (n=30) in random order. The dose of bupivacaine varied from 9~10 mg depending on the patients height. Maximum level of sensory blockade, time to reach T4 level, incidence of hypotension, time to get complete motor recovery, perioperative analgesic effect and complications were evaluated. RESULTS: There were no differences in maximum level of analgesia, time to reach T4 level and to get complete motor recovery, and incidence of hypotension between two groups. However, duration of analgesia was longer in group II with the bupivacaine/fentanyl mixture (191.9 +/- 77.6 min) than in group I with the bupivacaine alone (74.2 +/- 30.8 min). Spinal anesthesia was excellent in 100% of the fentanyl mixture group but in 80% of the bupivacine only group. CONCLUSION: 0.5% hyperbaric bupivacaine mixed with 25 g fentanyl provided improved perioperative analgesia without affecting the onset of sensory blockade and duration of motor blockade.