Effectiveness of continuous infusion of local anesthetic for pain control after median sternotomy: A single-center retrospective chart review

Abstract

After cardiac surgery via median sternotomy, postoperative pain impairs coughing and ambulation, potentially resulting in atelectasis and prolonged recovery. Opioid analgesics are typically given postoperatively but can cause complications such as constipation, sedation, confusion, and long-term abuse. In an effort to improve postoperative pain control, we examined the safety and effectiveness of continuous ropivacaine infusion for sternotomy-related pain. We performed a single-center, retrospective, observational chart review of patients who underwent coronary artery bypass grafting, valve surgery, or both via full median sternotomy. Patients were excluded if they had a previous history of chronic opioid use, required extracorporeal membrane oxygenation postoperatively, could not be extubated within 48 h, or died within 96 h of the initial operation. We identified 149 patients who met the study criteria: 71 who received continuous ropivacaine via an elastomeric pump (47.7%), and 78 (control group) who received no local anesthetic (52.3%). Median total opioid use and pain scores were not significantly different between patients who received ropivacaine via an elastomeric pump and control patients. Both groups had similar rates of ambulation by postoperative day 4 (69% vs. 63%; p = 0.43). The ropivacaine group was more often able to wean from oxygen by postoperative day 4 (43.7% vs. 26%; p = 0.021) and had a shorter median time to extubation (15.3 h vs. 16.6 h; p = 0.0017) and a shorter median hospital stay (6.9 d vs. 8.1 d; p = 0.0001). However, a multivariable analysis did not show the use of ropivacaine to be a predictor of shorter length of stay, so it is likely that other contributing factors caused the ropivacaine recipients to be discharged from the hospital earlier. In conclusion, continuous infusion of ropivacaine at the sternotomy site appears feasible and safe in cardiac surgery patients; however, its effectiveness in reducing pain scores or opioid use remains questionable and should be further studied with prospective randomized trials. Studies of other methods to reduce opioid use may also be warranted.