In this trial , 103 patients diagnosed with primary or metastatic liver cancer were recruited before transcatheter arterial infusion ( TAI ) of cisplatin or oxaliplatin and randomized to either group A ( 51 patients who were treated with the antiemetic tropisetron and acustimulation at the K1 acupoint for 20 minutes approximately 1 to 2 hours before TAI on the first day and then daily for the subsequent 5 days ) or group B ( 52 patients who were treated with tropisetron and electrostimulation at a placebo point on the heel ) .