Implementation of new protocol for pain management following cardiac surgery

Abstract

Aims: We assessed the implementation and effectiveness of an updated protocol designed to improve pain management in cardiac surgery patients. The new updated protocol was recommended systemic pain assessment every four hours unless patients were unstable, using the numerical rating score (NRS) after the endotracheal extubation. Our secondary aim was to analyze the factors predicting patients’ postoperative pain to guide development of future pain management protocols. Methods: Fifty patients undergoing cardiac surgery with median sternotomy were evaluated in this audit. Perioperative details and details regarding analgesic administration were collected. High-risk patients were classified as ones with a history of substance misuse, chronic pain, and preoperative opioid use. Pain was measured at rest, on coughing and on moving, for the first three postoperative days (POD), using 11-point NRS (0–10). Pain was considered “unacceptable” if it was NRS ≥4 at rest, and NRS ≥8 on activity. A univariate and multivariate mixed model linear regression was used to investigate factors that may contribute to pain following cardiac surgery. Results: On POD1 38% of patients reported unacceptable pain at rest, and 27% reported unacceptable pain on coughing or moving. There was limited implementation of the new protocol, thus we cannot comment on the effectiveness of the updated protocol. Multivariate analysis demonstrated an overall significant interaction effect between postoperative day and risk (p = 0.032). It was found that high-risk patients reported pain to be greater than pain reported by low-risk patients on POD3 (2.14, CI −0.32 to 4.26, p = 0.054). Use of preoperative gabapentin did not affect pain at rest nor pain on coughing or moving (p > 0.5). Conclusion: The new pain protocol was not followed in the majority of patient cases. Preoperatively, only 25 (56%) patients received gabapentin. No patients received patient-controlled analgesia (PCA) postoperatively. Seven (15%) patients identified as high risk received no differential pharmacological management contrary to the updated protocol. It is believed that e-mail is not sufficient to implement a new protocol such as this, thus resulting in protocol implementation failure. However, it was found that postoperative pain differed between high-and low-risk patients, especially at rest. This indicates that risk assessment and individualized pain protocols are important to optimize postoperative pain management following cardiac surgery. We have discussed the efforts required to improve future protocol implementation and pain management across disciplines.