Percutaneous procedures of the liver can be very painful and range from bliliary drain insertions to tumor ablation procedures. The study will randomize patients in two groups, one receiving a paravertebral nerve block prior to the procedure and one receiving a sham procedure in which saline will be injected in the paravertebral space. Pain scores and use of IV sedation will be monitored post procedure and both groups will be compared to assess whether paravetebral nerve blocks are effective at reducing pain in patients receiving such procedures.