Postoperative Pain in Patients Undergoing Cancer Surgery and Intravenous Patient-Controlled Analgesia Use: The First and Second 24 h Experiences.

Introduction: Postoperative cancer pain imposes severe physical and psychological problems. We aimed to investigate the pain experiences of patients with cancer after surgery, analyze the impact of infusion volume by patient-controlled analgesia (PCA), and explore the variations between day 1 and day 2.

Methods: Data were retrospectively extracted from a large health data platform. Descriptive statistics were presented for the demographic and clinical profiles of patients. Multiple logistic regression analyses were performed to evaluate associations between intensity of pain and PCA use after adjustment for risk factors.

Results: Among 11,383 patients with cancer, the incidence of pain (moderate to severe pain) was 93.3% (18.3%) at the first 24 h after operation, while the respect values decreased to 91.1% and 9.5% at the second 24 h. Further, female patients consistently experienced higher risk of pain over the whole 48 h postoperatively. Surgical sites were related to pain risk, with the highest risk among the respiratory system (OR 2.077, 95% CI 1.392-3.100). High doses of continuous volume (OR 2.453, 95% CI 1.742-3.456) and total volume (OR 2.830, 95% CI 2.037-3.934) of infusions were related to 1-3-fold elevated pain risk. Additionally, the observed associations were mostly repeated and could be up to over 10 times when pain was evaluated with number of PCA pump compressions instead of Numerical Rating Scale (NRS).

Conclusions: High risk of postoperative cancer pain, particularly among the high PCA dose group, could possibly indicate inadequate pain control, and presence of modifiable risk factors warrants more aggressive pain management strategies perioperatively.