Evaluation of pain management following cardiac surgery in an adult critical care unit in London, England

Abstract

Introduction: Effective pain management in the postoperative period is crucial for recovery after cardiac surgery. Various analgesic regimens, including opioid-based medications, patient-controlled analgesia (PCA), and adjunctive non-opioid therapies, are utilized in the critical care unit to manage pain. However, there is considerable variability in these practices, with differences in the choice of PCA drugs, opioid use, and adjunctive analgesics. The aim of this evaluation was to assess the current analgesic practices in a critical care setting, evaluate their efficacy in pain control, and gather patient feedback to optimize pain management protocols and provider education for improved postoperative outcomes. A secondary objective was to identify which if any analgesic regimen demonstrated superior efficacy, considering pain intensity reduction, adverse effect profile, and patient-reported outcomes. Method(s): The study was conducted over a four-week period in June 2024 at St Bartholomew's Hospital in London, England. Observational data were collected in real-time. All data were anonymized and recorded using a secure Microsoft Forms spreadsheet. The data collected included patient demographics (age, sex), surgical procedure type, preoperative renal function, prior analgesic use, and analgesics prescribed during the first 72 hours post-surgery. Analgesic regimens documented included the type and dose of PCA drugs (fentanyl, morphine, oxycodone), as well as the use of adjunctive analgesics like paracetamol. Additionally, pain and nausea scores were recorded, along with PCA adjustments and discontinuation times. Side effects of sedation, nausea, and vomiting were tracked. Patient-reported pain experiences and adverse effects were collected through structured patient interviews. Descriptive statistics were used to summarize the findings and identify patterns in analgesic use and outcomes. This study did not require ethics approval as it was a clinical evaluation. Result(s): Data from 57 patients showed that 16 (28%) received fentanyl PCA, 31 (54%) morphine PCA, and 10 (17.5%) oxycodone PCA. Only five patients (8.8%) required a PCA drug change. Fentanyl was associated with lower average pain scores (<1) and fewer nausea incidents compared to morphine and oxycodone. Fentanyl required fewer adjunctive analgesics than oxycodone (33.3% vs. 50%); however, morphine required fewer adjunctive analgesics than fentanyl (26.7% vs 33.3%). A total of 57 patients met the inclusion criteria and were analysed. Of these, 16 (28%) received fentanyl PCA, 31 (54%) received morphine PCA, and 10 (17.5%) received oxycodone PCA. Only five patients (8.8%) required a change in their PCA drug during the observation period. Fentanyl was associated with the lowest average pain scores (<1) and fewer episodes of nausea compared to both morphine and oxycodone. Additionally, fentanyl patients required fewer adjunctive analgesics (33.3%) compared to oxycodone (50%), while morphine had the fewest adjunctive analgesics required (26.7%). Conclusion(s): Opioid-based analgesia remains an effective strategy for managing postoperative pain following cardiac surgery. The current analgesic protocols at the hospital were found to be generally satisfactory in terms of pain control and adverse effects. These findings suggest fentanyl may offer superior pain control with a more favourable side-effect profile compared to other opioid regimens. However, further studies are needed to refine pain management strategies.