Pupillometry pain index decreases intraoperative sufentanyl administration in cardiac surgery: a prospective randomized study

Nociception level index-directed superficial parasternal intercostal plane block vs erector spinae plane block in open-heart surgery: a propensity matched non-inferiority clinical trial

This single-center study explored the efficacy of superficial parasternal intercostal plane block (SPIPB) versus erector spinae plane block (ESPB) in opioid-sparing within Nociception Level (NOL) index-directed anesthesia for elective open-heart surgery. After targeted propensity matching, 19 adult patients given general anesthesia with preincisional SPIPB were compared to 33 with preincisional ESPB. We hypothesized that SPIPB is non-inferior to ESPB in reducing total intraoperative fentanyl consumption, with a non-inferiority margin (δ) set at 0.1 mg. Intraoperative fentanyl dosing targeted a NOL index ≤ 25. Postoperatively, paracetamol 1 g 6-hourly and morphine for numeric rating scale (NRS) ≥ 4 were administered. This study could not demonstrate that SPIPB was inferior to ESPB for total intraoperative fentanyl consumption, as the confidence interval for the median difference of 0.1 mg (95% CI 0.05-0.15) crossed the predefined δ, with the lower bound falling below and the upper bound exceeding δ, p = 0.558. SPIPB led to higher postoperative morphine use at 24 and 48 h: 0 (0-40.6) vs. 59.5 (28.5-96.1) µg kg-1, p < 0.001 and 22.2 (0-42.6) vs. 63.5 (28.5-96.1) µg kg-1, p = 0.001. Four times fewer SPIPB patients remained morphine-free at 48 h, p < 0.001, and their time to first morphine dose was three times shorter compared to ESPB patients, p = 0.001. SPIPB led to higher time-weighted average NRS scores at rest, 1 (0-1) vs. 1 (1-2), p = 0.004, and with movement, 2 (1-2) vs. 3 (2-3), p = 0.002, calculated over the 48-h period post-extubation. The SPIPB group had a significantly higher average NOL index, p = 0.003, and greater NOL index variability, p = 0.027. This study could not demonstrate that SPIPB was inferior to ESPB for intraoperative fentanyl consumption. Significant differences were observed in secondary outcomes, with SPIPB leading to higher postoperative morphine use, higher pain scores, and reduced nociception control.

Progress in the validation of nociception monitoring in guiding intraoperative analgesic therapy

PURPOSE OF REVIEW

This article summarizes the current level of validation for several nociception monitors using a categorized validation process to facilitate the comparison of performance.

RECENT FINDINGS

Nociception monitors improve the detection of a shift in the nociception and antinociception balance during anesthesia, guiding perioperative analgesic therapy. A clear overview and comparison of the validation process for these monitors is missing.

RESULTS

Within a 2-year time-frame, we identified validation studies for four monitors [analgesia nociception index (ANI), nociception level monitor (NOL), surgical pleth index (SPI), and pupillometry]. We categorized these studies in one out of six mandatory validation steps: developmental studies, clinical validation studies, pharmacological validation studies, clinical utility studies, outcome improvement studies and economical evaluation studies. The current level of validation for most monitors is mainly focused on the first three categories, whereas ANI, NOL, and SPI advanced most in the availability of clinical utility studies and provide confirmation of a clinical outcome improvement. Analysis of economical value for public health effects is not yet publicly available for the studied monitors.

SUMMARY

This review proposes a stepwise structure for validation of new monitoring technology, which facilitates comparison between the level of validation of different devices and identifies the need for future research questions.

Feasibility of the pupillary pain index as a guide for depth of analgesia during opioid-sparing anesthesia with continuous infusion of dexmedetomidine

BACKGROUND

The pupillary dilation reflex (PDR) is an objective indicator of analgesic levels in anesthetized patients. Through measurement of the PDR during increasing tetanic stimulation (10-60 mA), it is possible to obtain the pupillary pain index (PPI), a score that assesses the level of analgesia.

OBJECTIVES

The depth of analgesia during opioid-sparing anesthesia (OSA) with continuous infusion of dexmedetomidine in addition to general anesthesia was assessed.

DESIGN

Observational prospective feasibility pilot study SETTING: This study was performed in the operating rooms of the Spedali Civili University-affiliated hospital of Brescia, Italy.

PATIENTS

Forty-five adults who underwent elective open (5-cm incision) surgery under general anesthesia (78% inhalation anesthesia), from Feb. 18th to Aug. 1st, 2019, were enrolled. Exclusion criteria were as follows: implanted pacemaker or ICD, ophthalmological comorbidities, chronic opioid use, peripheral neuropathy, other adjuvant drugs, epidural analgesia, or locoregional block.

MAIN OUTCOME MEASURES

The first aim was to verify the feasibility of applying a study protocol to evaluate the depth of analgesia during intraoperative dexmedetomidine administration using an instrumental pupillary evaluation. The secondary outcome was to evaluate appropriate analgesia, drug dosage, anesthesia depth, heart rate, blood pressure, transient side effects, postoperative nausea and vomiting (PONV), and pain numerical rating scale (NRS) score.

RESULTS

Thirty out of 50 patients (60%) treated with dexmedetomidine during the study period were included in the DEX group (8 males, age 42 ± 13 years, BMI 45 ± 8), and 15 other patients were included in the N-DEX group (8 males, age 62 ± 13 years, BMI 26 ± 6). Patients who underwent bariatric, abdominal, or plastic surgery were enrolled. At least 3 pupillary evaluations were taken for each patient. PPI ≤ 3 was observed in 97% of patients in the DEX group and 53% in the N-DEX group. Additionally, the DEX group received less than half the remifentanil dose than the N-DEX group (0.13 ± 0.07 vs 0.3 ± 0.11 mcg kg-1 min-1). The average dose of dexmedetomidine administered was 0.17 ± 0.08 mcg kg-1 h-1.

CONCLUSION

The feasibility of applying the protocol was verified. An OSA strategy involving dexmedetomidine may be associated with improved analgesic stability: a randomized controlled trial is necessary to verify this hypothesis.

TRIAL REGISTRATION

Trial.gov registration number: NCT05785273.

Balanced Nonopioid General Anesthesia With Lidocaine Is Associated With Lower Postoperative Complications Compared With Balanced Opioid General Anesthesia With Sufentanil for Cardiac Surgery With Cardiopulmonary Bypass: A Propensity Matched Cohort Study

BACKGROUND

There are no data on the effect of balanced nonopioid general anesthesia with lidocaine in cardiac surgery with cardiopulmonary bypass. The main study objective was to evaluate the association between nonopioid general balanced anesthesia and the postoperative complications in relation to opioid side effects.

METHODS

Patients undergoing cardiac surgery with cardiopulmonary bypass between 2019 and 2021 were identified. After exclusion of patients for heart transplantation, left ventricular assistance device, and off-pump surgery, we classified patients according to an opioid general balanced anesthesia or a nonopioid balanced anesthesia with lidocaine. The primary outcome was a collapsed composite of postoperative complications that comprise respiratory failure and confusion, whereas secondary outcomes were acute renal injury, pneumoniae, death, intensive care unit (ICU), and hospital length of stay.

RESULTS

We identified 859 patients exposed to opioid-balanced general anesthesia with lidocaine and 913 patients exposed to nonopioid-balanced general anesthesia. Propensity score matching yielded 772 individuals in each group with balanced baseline covariates. Two hundred thirty-six patients (30.5%) of the nonopioid-balanced general anesthesia versus 186 patients (24.1%) presented postoperative composite complications. The balanced lidocaine nonopioid general anesthesia group was associated with a lower proportion with the postoperative complication composite outcome OR, 0.72 (95% CI, 0.58-0.92; P = .027). The number of patients with acute renal injury, death, and hospital length of stay did not differ between the 2 groups.

CONCLUSIONS

A balanced nonopioid general anesthesia protocol with lidocaine was associated with lower odds of postoperative complication composite outcome based on respiratory failure and confusion.

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

Background and Objectives: The erector spinae plane block (ESPB) is an analgesic adjunct demonstrated to reduce intraoperative opioid consumption within a Nociception Level (NOL) index-directed anesthetic protocol. We aimed to examine the ESPB effect on the quality of intraoperative nociception control evaluated with the NOL index. Materials and Methods: This is a post hoc analysis of the NESP (Nociception Level Index-Directed Erector Spinae Plane Block in Open Heart Surgery) randomized controlled trial. Eighty-five adult patients undergoing on-pump cardiac surgery were allocated to group 1 (Control, n = 43) and group 2 (ESPB, n = 42). Both groups received general anesthesia. Preoperatively, group 2 received bilateral single-shot ESPB (1.5 mg/kg/side 0.5% ropivacaine mixed with dexamethasone 8 mg/20 mL). Until cardiopulmonary bypass (CPB) was initiated, fentanyl administration was individualized using the NOL index. The NOL index was compared at five time points: pre-incision (T1), post-incision (T2), pre-sternotomy (T3), post-sternotomy (T4), and pre-CPB (T5). On a scale from 0 (no nociception) to 100 (extreme nociception), a NOL index > 25 was considered an inadequate response to noxious stimuli. Results: The average NOL index across the five time points in group 2 to group 1 was 12.78 ± 0.8 vs. 24.18 ± 0.79 (p < 0.001). The NOL index was significantly lower in the ESPB-to-Control group at T2 (12.95 ± 1.49 vs. 35.97 ± 1.47), T3 (13.28 ± 1.49 vs. 24.44 ± 1.47), and T4 (15.52 ± 1.49 vs. 34.39 ± 1.47) (p < 0.001) but not at T1 and T5. Compared to controls, significantly fewer ESPB patients reached a NOL index > 25 at T2 (4.7% vs. 79%), T3 (0% vs. 37.2%), and T4 (7.1% vs. 79%) (p < 0.001). Conclusions: The addition of bilateral single-shot ESPB to general anesthesia during cardiac surgery improved the quality of intraoperative nociception control according to a NOL index-based evaluation.

Pupillary reflex dilation and pain index evaluation during general anesthesia using sufentanil: a double-blind randomized controlled trial

Aim: In a single-center, double-blind, randomized controlled trial, we evaluated whether pupillometry-controlled use of sufentanil is better than free-choice administration of sufentanil by anesthesiologists. Patients & methods: 61 patients undergoing daycare gynecological or abdominal surgery were enrolled. A pupillometry pain index score chart was introduced for administration guidance of sufentanil. Results: The first objective, patient well-being, did not show a significant difference with painkiller usage and health state index at day 1 postoperatively. Secondly, we experienced difficulty in interpretation of the pupillometry score. Thirdly, opioid usage was higher in the intervention group (20.1 vs 14.8 mcg; p = 0.017). Conclusion: The use of pupillometry and pain index chart for bolus sufentanil with our protocol showed an unwanted higher sufentanil usage without a significant difference in patient wellbeing. (Ethics Committee EC17/28/319 of the University Hospital of Antwerp. Registration at clinicaltrials.gov NCT03248908.).