Practice Advisory for Preoperative and Intraoperative Pain Management of Cardiac Surgical Patients: Part 2

Intraoperative Methadone Use Is Associated With Reduced Postoperative Pain and More Rapid Opioid Weaning After Coronary Artery Bypass Grafting

OBJECTIVE

To explore the association between intraoperative methadone use, postoperative pain, and opioid consumption after coronary artery bypass grafting (CABG) surgery.

DESIGN

Retrospective cohort study.

SETTING

Single academic medical center.

PARTICIPANTS

Patients undergoing isolated CABG over a 5-year period.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Demographic data, comorbidities, and intraoperative anesthetic medications were recorded. Primary study outcomes were average and maximum pain scores and morphine milligram equivalent consumption on the first 2 postoperative days (PODs). Linear mixed-effects regression models were used to examine the effect of intraoperative methadone use on study outcomes. Among 1,338 patients, 78.6% received intraoperative methadone (0.2 mg/kg). Patients who did not receive methadone had higher average (estimated [Est], 0.48; 95% confidence interval [CI], 0.22-0.73; p < 0.001) and maximum postoperative (Est, 0.49; 95% CI, 0.23-0.75; p < 0.001) pain scores over PODs 0 to 2. For postoperative opioid consumption, there was a significant intraoperative methadone use-time interaction effect on postoperative opioid use (odds ratio [OR], 2.21; 95% CI, 1.74-2.80; p < 0.001). Across PODs 0 to 2, patients who received intraoperative methadone had a faster decline in postoperative opioid use than those who did not receive intraoperative methadone. Patients who did not receive intraoperative methadone were extubated slightly faster (OR, 0.82; 95% CI, 0.72-0.93; p < 0.01).

CONCLUSIONS

Our data suggest that the use of intraoperative methadone is safe, reduces postoperative pain, and expedites weaning from postoperative opioids after CABG surgery.

Perioperative Pain Management for Thoracic Surgery: A Multi-Layered Approach

Cardiothoracic surgeries frequently pose unique challenges in the management of perioperative acute pain that require a multifaceted and personalized approach in order to optimize patient outcomes. This article discusses various analgesic strategies including regional anesthesia techniques such as thoracic epidurals, erector spinae plane blocks, and serratus anterior plane blocks and underscores the significance of perioperative multimodal medications, while providing nuanced recommendations for their use. This article further attempts to provide evidence for the efficacy of the different modalities and compares the effectiveness of the choice of analgesia. The roles of Acute Pain Services (APS) and Transitional Pain Services (TPS) in mitigating opioid dependence and chronic postsurgical pain are also discussed. Precision medicine is also presented as a potential way to offer a patient tailored analgesic strategy. Supported by various randomized controlled trials and meta-analyses, the article concludes that an integrated, patient-specific approach encompassing regional anesthesia and multimodal medications, while also utilizing the services of the Acute Pain Service can help to enhance pain management outcomes in cardiothoracic surgery.

Superficial parasternal intercostal plane blocks in cardiac surgery: a systematic review and meta-analysis

PURPOSE

Traditional multimodal analgesic strategies have several contraindications in cardiac surgery patients, forcing clinicians to use alternative options. Superficial parasternal intercostal plane blocks, anesthetizing the anterior cutaneous branches of the thoracic intercostal nerves, are being explored as a straightforward method to treat pain after sternotomy. We sought to evaluate the literature on the effects of superficial parasternal blocks on pain control after cardiac surgery.

METHODS

We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs). We searched MEDLINE, Embase, CENTRAL, and Web of Science databases for RCTs evaluating superficial parasternal intercostal plane blocks in adult patients undergoing cardiac surgery via midline sternotomy published from inception to 11 March 2022. The prespecified primary outcome was opioid consumption at 12 hr. The risk of bias was assessed with the Cochrane Collaboration Risk of Bias Tool, and the quality of evidence was evaluated using the grading of recommendations, assessments, development, and evaluations. Outcomes were analyzed with a random-effects model. All subgroups were prespecified.

RESULTS

We reviewed 1,275 citations. Eleven RCTs, comprising 756 patients, fulfilled the inclusion criteria. Only one study reported the prespecified primary outcome, precluding the possibility of meta-analysis. This study reported a reduction in opioid consumption (-11.2 mg iv morphine equivalents; 95% confidence interval [CI], -8.2 to -14.1) There was a reduction in opioid consumption at 24 hr (-7.2 mg iv morphine equivalents; 95% CI,  -5.6 to -8.7; five trials; 436 participants; moderate certainty evidence). All five studies measuring complications reported that none were detected, which included a sample of 196 blocks.

CONCLUSION

The literature suggests a potential benefit of using superficial parasternal blocks to improve acute postoperative pain control after cardiac surgery via midline sternotomy. Future studies specifying dosing regimens and adjuncts are required.

STUDY REGISTRATION

PROSPERO (CRD42022306914); first submitted 22 March 2022.

Peripheral Regional Anesthetic Techniques in Cardiac Surgery: A Systematic Review and Meta-Analysis

OBJECTIVE

The aim of this systematic review was to investigate postoperative pain outcomes and adverse events after peripheral regional anesthesia (PRA) compared to no regional anesthesia (RA), placebo, or neuraxial anesthesia in children and adults undergoing cardiac surgery.

DESIGN

A systematic review and meta-analysis with an assessment of the risk of bias (Cochrane RoB 1) and certainty of evidence (Grading of Recommendations, Assessment, Development, and Evaluation).

SETTING

Randomized controlled trials (RCTs).

PARTICIPANTS

Adults and children undergoing heart surgery.

INTERVENTIONS

Any kind of PRA compared to no RA or placebo or neuraxial anesthesia.

MEASUREMENTS AND MAIN RESULTS

In total, 33 RCTs (2,044 patients) were included-24 of these had a high risk of bias, and 28 were performed in adults. Compared to no RA, PRA may reduce pain intensity at rest 24 hours after surgery (mean difference [MD] -0.81 points, 95% CI -1.51 to -0.10; I2 = 92%; very low certainty evidence). Peripheral regional anesthesia, compared to placebo, may reduce pain intensity at rest (MD -1.36 points, 95% CI -1.59 to -1.13; I2 = 54%; very low certainty evidence) and during movement (MD -1.00 points, 95% CI -1.34 to -0.67; I² = 72%; very low certainty evidence) 24 hours after surgery. No data after pediatric cardiac surgery could be meta-analyzed due to the low number of included trials.

CONCLUSIONS

Compared to no RA or placebo, PRA may reduce pain intensity at rest and during movement. However, these results should be interpreted cautiously because the certainty of evidence is only very low.