Abstract: Objective To investigate risk factors of moderate and severe pain in patients with hepatocellular carcinoma (HCC) after radiofrequency ablation (RFA).Methods One hundred and two patients with HCC who underwent computed tomography (CT)-guided percutaneous RFA under general anesthesia were enrolled. According to the visual analog scale (VAS) within 24 hours after operation, patients were divided into moderate and severe pain group (VAS ≥ 3 points) and non moderate/severe pain group (VAS < 3 points). Clinical data of the patients including gender, age, American Society of Anesthesiologists (ASA[A1]) classification, history of cirrhosis and liver surgery, preoperative pain, tumor size, tumor location, distance between tumor and liver capsule, tumor number, ablation number, ablation time and operation time were collected. Multivariate logistic regression analysis was performed to screen the risk factors for moderate and severe pain after operation.Results Fifty-six patients (54.9%) had moderate or severe pain within 24 hours after operation. Compared with the non moderate/severe pain group, the proportion of preoperative pain, tumor size > 1.5cm and ablation time > 12min in the moderate and severe pain group were higher (P<0.05). Multivariate logistic regression analysis showed that tumor focus > 1.5 cm and ablation time > 12 min were independent risk factors of moderate and severe pain in HCC patients after RFA (P<0.05).Conclusion Tumor size > 1.5 cm or RFA time > 12 min are positively related to the occurrence of moderate and severe pain in HCC patients after operation. Prompt analgesic treatment after RFA should be paid more attention to.

Key words: Hepatocellular carcinoma, Radiofrequency ablation, Pain, Risk factors