Thoracic Paravertebral Block With Methylene Blue Visual Confirmation for Postoperative Pain After VATS Lobectomy

The paravertebral space is identified under ultrasound guidance and after negative aspiration a 3 ml test dose of anesthetic is injected. After observing widening of the paravertebral space and anterior pleural displacement to confirm the correct needle positioning, a bolus dose of 20 mL 0.5% ropivacaine with a solution of 1 ml 1% methylene blue and 4 ml of saline will be injected in the paravertebral space. At the start of the surgery, the spread of the solution of anesthetic and methylene blue will be assessed through visualization in thoracoscopy and if necessary the block will be repeated. After the surgery, intravenous acetaminophen will be administered 3 times daily and tramadol 50 mg will be prescribed as rescue analgesic.

The epidural catheter will be placed using the loss of resistance technique, and after ruling out intravenous or intrathecal catheter placement with a negative aspiration test dose, an initial dose of 10 mL 0.25% bupivacaine will be injected. Continuous infusion will be started with with 0.125 % bupivacaine + fentanyl 0.5 mcg/ ml at 6-10 ml/hour will be started based on the patient weight for 48 hours postoperatively. After the surgery, intravenous acetaminophen will be administered 3 times daily and tramadol 50 mg will be prescribed as rescue analgesic.