A Systematic Review of Multimodal Analgesic Effectiveness on Acute Postoperative Pain After Adult Cardiac Surgery

Aim: To synthesise the best available empirical evidence about the effectiveness of multimodal analgesics on pain after adult cardiac surgery.

Design: A systematic review with meta-analysis.

Methods: Indexed full-text papers or abstracts, in any language, of randomised controlled trials of adult patients undergoing cardiac surgery investigating multimodal postoperative analgesic regimen effect on mean level of patient-reported pain intensity at rest.

Data sources: Eight databases, via two platforms and three trial registries were searched from 1 January 1995 to 1 June 2024 returning 3823 citations.

Results: Of the 123 full-text papers assessed, 29 were eligible for inclusion. Data were independently extracted by a minimum of two reviewers in Covidence. There were 2195 participants, aged 60.4 ± 6.6 (range 40-79) years, who were primarily male (n = 1522, 76.1%), randomised in the included studies. Risk of bias was high and reporting quality was poor. Patient-reported pain was measured at rest in 28 (96.6%) trials. Data were suitable for pooled analysis from 10 (34.5%) of these trials with an average rest pain intensity of 3.3 (SD 1.5) in the control and 2.7 (SD 1.9) in the intervention groups, respectively. No trials compared combinations of nonopioid, opioid-agonist-antagonist, partial opioid agonists or full opioid agonists. Most trials (n = 11, 37.9%) compared two different full opioid options for less than 72 h (n = 24, 82.7%).

Conclusions: Robust trials are needed to determine which multimodal analgesic combination will optimise patient recovery after adult cardiac surgery. There is an urgent need to test and refine high-quality end-point measures.

Implications for patient care: Adequate assessment precedes ideal pain treatment. The findings from this review reveal neither are sufficient, and the impact of suboptimal pain management on postoperative recovery is grossly underinvestigated.

Impact: The optimal combination of multimodal analgesics is unknown despite being recommended in best practice guidelines for enhanced recovery after cardiac surgery. Almost 30% of adults continue to experience ongoing pain up to a year after cardiac surgery, and findings from this review reveal a dearth of robust empirical evidence for optimal pain management, and heterogeneity in the way pain is assessed, measured and managed. This review provides a premise for robust trials focused on acute postoperative recovery in cardiac surgery and beyond.

Reporting method: This review was conducted in accordance with the PRISMA-P statement.

Patient or public contribution: There was no patient or public contribution.

Protocol registration: PROSPERO: CRD42022355834.