Reducing pre-operative delays in urgent cardiac surgery: evidence for waiting-time effect on post-operative length of stay

Background According to the National Institute of Cardiovascular Outcomes Research (NICOR) report in 2022, the mean waiting time for urgent coronary artery bypass graft (CABG) surgery in the United Kingdom is 10 days, rather than the recommended 7 days. We conducted a service evaluation of the acute cardiac pathway in our hospital. Methods All patients who received cardiac surgery in 2022 were considered. 611 patients had cardiac surgery; 585 had elective or acute cardiac surgery; 580 had complete data for analysis. Data were reported in counts and percentages. We determined the associations between pre-operative length of stay and post-operative outcomes using negative binomial analysis. Fine-Gray model was used to address survival bias. Results Median pre-operative LOS for urgent patients referred directly to CHH was 12 days (IQR 8.0-16.5, p < 0.001). Each additional pre-operative day were associated with an increase of stay (LOS) by 3.2%. Sensitivity analysis on the pre-operative LOS rate ratio shows that this effect is purely confined to the urgent population; RR 1.030, p < 0.001 and absent in elective patients; RR 0.976, p 0.3966. The effect is enhanced in patients presenting to Castle Hill Hospital (CHH) directly as we were able to capture the full duration of their in-hospital LOS; RR 1.035, p < 0.001. Other factors that impact post-operative LOS were presenting ejection fraction (EF), type of surgery and age. Conclusion Pre-operative LOS was independently associated with prolonged post-operative stay. This effect is confined to the urgent population supporting a service improvement focus on reducing in-hospital delays for the urgent pathway.