Propofol total intravenous anaesthesia versus inhalational anaesthesia for acute postoperative pain in patients with morphine patient-controlled analgesia: a large-scale retrospective study with covariate adjustment

BACKGROUND: To compare the postoperative analgesic effect of propofol total intravenous anaesthesia (TIVA) versus inhalational anaesthesia (GAS) in patients using morphine patient-controlled analgesia (PCA). METHODS: A retrospective cohort study was performed in a single tertiary university hospital. Adult patients who used PCA morphine after general anaesthesia across 15 types of surgeries were included. Patients who received propofol TIVA were compared to those who had inhalational anaesthesia. Primary outcomes assessed were postoperative numerical rating scale (NRS) pain scores and postoperative opioid consumption. RESULTS: Data from 4202 patients were analysed. The overall adjusted NRS pain scores were significantly lower in patients who received propofol TIVA at rest (GEE: β estimate of the mean on a 0 to 10 scale = -0.56, 95% CI = (-0.74 to -0.38), p < 0.001; GAS as reference group) and with movement (β estimate = -0.89, 95% CI = (-1.1 to -0.69), p < 0.001) from postoperative days (POD) 1–3. Propofol TIVA was associated with lower overall adjusted postoperative morphine consumption (β estimate = -3.45, 95% CI = (-4.46 to -2.44), p < 0.001). Patients with propofol TIVA had lower adjusted NRS pain scores with movement for hepatobiliary/pancreatic (p < 0.001), upper gastrointestinal (p < 0.001) and urological surgeries (p = 0.005); and less adjusted postoperative morphine consumption for hepatobiliary/pancreatic (p < 0.001), upper gastrointestinal (p = 0.006) and urological surgeries (p = 0.002). There were no differences for other types of surgeries. CONCLUSION: Propofol TIVA was associated with statistically significant, but small reduction in pain scores and opioid consumption in patients using PCA morphine. Subgroup analysis suggests clinically meaningful analgesia possibly for hepatobiliary/pancreatic and upper gastrointestinal surgeries. TRIAL REGISTRATION: This study is registered at ClinicalTrials.gov (NCT03875872). SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12871-022-01683-9.