The effect of continuous bilateral parasternal block with lidocaine on patient-controlled analgesia opioid requirement and recovery after open heart surgery: a double-blind randomised controlled trial.

Background: We hypothesised that a continuous 72-h bilateral parasternal infusion of lidocaine at 2×35 mg h Methods: We randomly allocated 45 participants to a 72-h bilateral parasternal infusion of lidocaine or saline commencing after wound closure. The primary outcome was the cumulative patient-controlled analgesia (PCA) morphine consumption at 72 h. Secondary outcomes included total morphine requirement, pain, peak expiratory flow, and serum interleukin-6 concentration. In addition, we used an eHealth platform for a 3-month follow-up of pain, analgesic use, and Quality of Recovery-15 scores. Results: The 72-h PCA morphine requirement was significantly lower in the lidocaine than the saline group (10 mg [inter-quartile range: 5-19 mg] and 28.2 mg [inter-quartile range: 16-42.5 mg], respectively; Conclusions: After sternotomy for open heart surgery, a 72-h bilateral parasternal lidocaine infusion significantly decreased PCA and total morphine requirement. However, neither signs of decreased inflammatory response nor an improvement in recovery was seen. Clinical trial registration: EudraCT number 2018-004672-35.