Objectives: Prior work on postoperative pain trajectories has examined pain score changes over time using daily averages of pain scores. However, little is known about the time required until patients consistently report minimal postoperative pain.
Materials and methods: We conducted a retrospective cohort study of surgical case data from 7293 adult patients to examine the impact of age, sex, and the type of surgery on the time to sustained postoperative pain relief (SuPPR). We defined SuPPR as the time required until a patient reports the first of multiple (2, 3, 4, or 5 sequential measurements; eg, SuPPR-2, SuPPR-3), uninterrupted, mild pain scores (≤4/10).
Results: Overall, SuPPR times ranged from 3 minutes for SuPPR-2 and 9 minutes for SuPPR-5 to 160.1 hours for SuPPR-2 and 183.1 hours for SuPPR-5. For the SuPPR-2 outcome, the median time to event was 10.9 hours (interquartile range, 3 to 26.1 h) after surgery. For the SuPPR-5 outcomes, the median time to event was 31.5 hours (interquartile range, 17.8 to 54.2 h) after surgery. The peak median difference between 2 sequential SuPPR definitions was between SuPPR-3 and SuPPR-2 at 9 hours, with subsequent decreases to 6.5 hours between SuPPR-4 and SuPPR-3, and 5.2 hours between SuPPR-5 and SuPPR-4. There were statistically different differences across SuPPR-2 through SuPPR-5 definitions by age, sex, and type of surgery.
Discussion: Although additional analyses are necessary, SuPPR may represent a novel method for evaluating acute pain service performance.