Chest Tube-Delivered Bupivacaine to Decrease Postoperative Pain After Cardiac Surgery

Background:

After heart surgery, patients require temporary chest tubes - plastic drains placed inside the chest to prevent fluid building up around the heart and lungs. These tubes are often very painful and can limit breathing, coughing, and movement, which necessitates usage of painkiller medication (opioids and non-steroidal anti-inflammatory drugs (NSAIDs)) that have negative side effects and can prolong hospital recovery. Despite this common problem, routine care lacks simple, add-on strategies that directly numb pain at the chest tube sites rather than relying solely on whole-body painkiller medicine.

Purpose:

To determine whether injecting a long-acting numbing medicine (bupivacaine 0.5%) through chest tubes safely reduces pain and lowers opioid and NSAID use compared with placebo.

Objective:

With ethics approval, data access, and study procedures already in place before May, the specific objective for this studentship is to collect and analyze data to evaluate the short-term effect of bupivacaine versus placebo on:

* Mean pain scores from initial recovery to chest tube removal * Total mean opioid and NSAID use

Methods:

This single-centre, 1:1 block randomized, double-blind, placebo-controlled trial will enroll 60 adults undergoing coronary artery bypass (procedure to bypass blocked blood vessels supplying heart muscle using healthy blood vessels) at the Foothills Medical Centre. Patients receive either 10 mL bupivacaine 0.5% or normal saline (saltwater placebo) through chest tubes by heart surgeons whenever pain hits ≥3/10 using the Numeric Rating Scale (0 = no pain; 10 = most intense pain), from initial recovery to chest tube removal. Standard pain care will continue for all patients. The study team will record pain scores, opioid and NSAID doses, and any side effects for each group. Interval pain reduction will be measured 30, 60, 120 and 240 minutes post injection. Mean pain reduction and total painkiller use will be compared between the two groups.