One hundred and six adult patients undergoing elective cardiac surgery with cardiopulmonary bypass.
Patients were randomized into 2 groups. Patients in group 1 (ESP block group, n = 53) received ultrasound-guided bilateral ESP block with 3 mg/kg of 0.375% ropivacaine before anesthesia induction at the T6 transverse process level. Patients in group 2 (paracetamol and tramadol group, n = 53) received paracetamol (1 gm every 6 hours) and tramadol (50 mg every 8 hours) intravenously in the postoperative period. The primary study outcome was to evaluate pain at rest using an 11-point numeric rating scale (NRS). Mann-Whitney U test was used for comparing NRS scores.
Measurements and Main Results
The postoperative pain level after extubation and duration of analgesia during which NRS was < 4 of 10 was compared between the groups. The median pain score at rest after extubation in group 1 was 0 of 10 until hour 6, 3 of 10 at hour 8, and 4 of 10 at hours 10 and 12 postextubation. These were significantly less in comparison with group 2 (p = 0.0001). Patients in group 1 had a significantly higher mean duration of analgesia (8.98 ± 0.14 hours), during which NRS was < 4 of 10, compared with group 2 (4.60 ± 0.12 hours) (p = 0.0001).
ESP block safely provided significantly better pain relief at rest for longer duration as compared to intravenous paracetamol and tramadol.