ObjectivesThis study aimed to validate the efficacy and safety of contrast-enhanced ultrasound-guided percutaneous transhepatic cholangiodrainage (CEUS-PTCD) as a biliary drainage procedure in patients with malignant biliary obstruction and stage 3 chronic kidney disease (CKD3). Materials and methodsBetween January 2019 and December 2023, 634 patients who underwent CEUS-PTCD were retrospectively enrolled in this study. During the procedure, imaging parameters such as the maximum diameter of the dilated bile duct, presence of ascites, detailed findings from CEUS, and clinical outcomes were meticulously recorded. Laboratory results, including serum bilirubin levels, liver function tests, and estimated glomerular filtration rate (eGFR), were evaluated in one day before and three days after procedure. The aforementioned parameters were compared using the paired-sample t test and the Wilcoxon test. ResultsA total of 66 (10.41 %) patients with malignant biliary obstruction and CKD3 were included in the final analysis (median age: 66, range: 30–89 years, 46 males and 20 females). Procedure records indicated that 23 patients (34.8 %) had a maximum biliary duct dilation diameter of ≤ 4 mm, while 5 patients (7.6 %) exhibited mild ascites. Additionally, 24 patients (36.4 %) had ultrasound contrast agent entry into both the biliary duct and bloodstream. All patients successfully achieved external bile drainage following CEUS-PTCD, with no significant complications observed during or after the intervention. Post-procedure, there was a statistically significant reduction in all previously elevated serum bilirubin and liver enzyme levels (P-values were less than 0.05). Furthermore, no statistically significant alterations in eGFR were observed prior to or following CEUS-PTCD across all patients (P = 0.295), including comparisons between groups with and without the ultrasound contrast agent into the bloodstream (P = 0.254). ConclusionCEUS-PTCD is a safe and effective biliary drainage procedure for patients with malignant biliary obstruction and CKD3.