Nociception Level Index-Directed Erector Spinae Plane Block in Open Heart Surgery: A Randomized Controlled Clinical Trial

Abstract

Background and Objectives: The erector spinae plane block (ESPB) is a multimodal opioid-sparing component, providing chest-wall analgesia of variable extent, duration, and intensity. The objective was to examine the ESPB effect on perioperative opioid usage and postoperative rehabilitation when used within a Nociception Level (NOL) index-directed anesthetic protocol. Materials and Methods: This prospective, randomized, controlled, open-label study was performed in adult patients undergoing on-pump cardiac surgery in a single tertiary hospital. Eighty-three adult patients who met eligibility criteria were randomly allocated to group 1 (Control, n = 43) and group 2 (ESPB, n = 40) and received general anesthesia with NOL index-directed fentanyl dosing. Preoperatively, group 2 also received bilateral single-shot ultrasound-guided ESPB (1.5 mg/kg/side 0.5% ropivacaine mixed with dexamethasone 8 mg/20 mL). Postoperatively, both groups received intravenous paracetamol (1 g every 6 h). Morphine (0.03 mg/kg) was administered for numeric rating scale (NRS) scores ≥4. Results: The median (IQR, 25th–75th percentiles) intraoperative fentanyl and 48 h morphine dose in group 2-to-group 1 were 1.2 (1.1–1.5) vs. 4.5 (3.8–5.5) µg·kg−1·h−1 (p < 0.001) and 22.1 (0–40.4) vs. 60.6 (40–95.7) µg/kg (p < 0.001). The median (IQR) time to extubation in group 2-to-group 1 was 90 (60–105) vs. 360 (285–510) min (p < 0.001). Two hours after ICU admission, 87.5% of ESPB patients were extubated compared to 0% of controls (p < 0.001), and 87.5% were weaned off norepinephrine compared to 46.5% of controls (p < 0.001). The median NRS scores at 0, 6, 12, 24, and 48 h after extubation were significantly decreased in group 2. There was no difference in opioid-related adverse events and length of stay. Conclusions: NOL index-directed ESPB reduced intraoperative fentanyl by 73.3% and 48 h morphine by 63.5%. It also hastened the extubation and liberation from vasopressor support and improved postoperative analgesia.

Nociception Control of Bilateral Single-Shot Erector Spinae Plane Block Compared to No Block in Open Heart Surgery—A Post Hoc Analysis of the NESP Randomized Controlled Clinical Trial

“…The original NESP trial was registered with (Identifier: NCT04338984) and was approved by the Institutional Review Board for Biomedical Research of Prof. Dr. C.C. Iliescu Emergency Institute for Cardiovascular Diseases, Bucharest, Romania (2019.07.26/18750) [ 18 ].…”

“…Detailed methods were previously reported [ 18 ]. In brief, all the patients received standard cardiac anesthesia monitoring.…”

“…In both groups, intraoperative fentanyl administration followed a standard protocol to attain optimum NAN balance defined as a NOL index between 10 and 25 (i.e., 10 ≤ target NOL index ≤ 25) on a scale from 0 (i.e., absence of nociception) to 100 (i.e., extreme nociception). The original NAN protocol is reiterated herein [ 18 ]: (1) after induction, start fentanyl at 2 µg·kg −1 ·h −1 in both groups; (2) if the NOL index is >25 for more than 60 s, increase the infusion by 0.5 µg·kg −1 ·h −1 and bolus 1 µg/kg; (3) if the NOL index is <10 for more than 60 s, decrease the infusion by 0.5 µg·kg −1 ·h −1 ; (4) after a dose change, allow an observation window of three minutes; and (5) stop the fentanyl infusion when it reaches 0.5 µg·kg −1 ·h −1 with the NOL index ≤ 25 for more than ten minutes ( Figure 1 ). After CPB initiation, fentanyl administration was left to the discretion of the attending anesthetist, who had to pursue hemodynamic stability within 15% of the mean arterial pressure recorded during optimum NAN balance.…”

“…In the NESP study, we provided a detailed sampling size calculation for the initial primary outcome (i.e., intraoperative fentanyl consumption) that gave a minimum number of patients per group of 28 [ 18 ]. For this post hoc study, statistical analyses were performed using NCSS 2022 Statistical Software (NCSS, v22.0.2, LLC, Kaysville, UT, USA).…”

“…We recently published the results of the NESP (Nociception Level Index-Directed Erector Spinae Plane Block in Open Heart Surgery) randomized controlled clinical trial [ 18 ]. In the NESP trial, we compared NOL index-directed general anesthesia (NDGA) to NDGA combined with preemptive bilateral single-shot ESPB.…”