The utility of post-biopsy ultrasonography in detecting complications after percutaneous liver biopsy in children.

Abstract

Surveillance post image-guided percutaneous liver biopsy in children is variable. The aim of this study was to assess the value of 4-6-h post-procedure ultrasonography (US) in detecting post-liver-biopsy hemorrhage. This prospective study included pediatric patients who underwent US-guided percutaneous liver biopsies. All children had a US study obtained pre-procedure and one obtained 4-6h post-procedure; US examinations were deemed positive if abnormalities were present. We also reviewed any subsequent imaging that was performed within 7days (late imaging) at the discretion of the referring team. Changes in US findings (ΔUS) were graded by two radiologists using a descriptive non-validated scale (none, minimal, marked). Hemoglobin (Hb) levels were assessed pre-procedure and 4h post-procedure. The diagnostic accuracy of US changes for detecting post-procedural hemorrhage was calculated based on a drop in Hb >1.5g/dL or Hb >15% from baseline (ΔHb). We used a Kruskal-Wallis test to correlate the ΔHb with ΔUS. Association between late-imaging and post-procedure US findings was tested using a chi-square test. We included 224 biopsies. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of post-procedure US in detecting post-procedure hemorrhage ranged 26.3-42.1%, 72.4-93.3%, 0.22-0.42, and 0.87-0.88, respectively. No significant association was seen between the ΔHb and sonographic findings (P=0.068). No significant difference was seen in the need for late imaging between children who did and those who did not have positive US findings (P=0.814). The sensitivity and PPV of post-procedure US in detecting post-procedural hemorrhage are low. Our findings do not support routine post-procedure surveillance US.