Table 1

Patient characteristics, primary and secondary outcomes

Intervention (n=34)Control (n=34)P value
Patient characteristics
 Age, mean (SD)32.3 (5.7)31.5 (4.9)n.s.
 Weight (kg), median (range)84.5 (57–119)84.5 (63–106)n.s.
 BMI, kg/m2 (SD)31.2 (5.5)30.2 (3.4)n.s.
Primary outcome
 Oral morphine equivalents 0–24, mean (SD)65.3 (47.9)94.3 (60.0)0.03
Secondary outcomes
 Oral morphine equivalents 0–6 hours, mean (SD)15.3 (17.3)34.7 (31.2)<0.003*
 Oral morphine equivalents 6–12 hours, mean (SD)24.9 (19.7)27.7 (28.6)n.s.
 Oral morphine equivalents 12–18 hours, mean (SD)13.5 (12.5)19.9 (15.3)n.s.
 Oral morphine equivalents 18–24 hours, mean (SD)11.7 (13.7)12.1 (13.2)n.s.
 NRS score at rest 0–6 hours, median (IQR)0.8 (0.3–2.0)2.1 (0.8–2.9)<0.01*
 NRS score at rest 6–12 hours, median (IQR)2.8 (1.0–4.0)2.8 (1.5–5.0)n.s.
 NRS score at rest 12–24 hours, median (IQR)2.0 (1.0–4.0)2.3 (1.5–4.5)n.s.
 NRS score at activity 0–6 hours, median (IQR)1.3 (0.8–2.0)2.5 (1.3–3.6)<0.003*
 NRS score at activity 6–12 hours, median (IQR)3.3 (2.0–5.0)4.0 (2.5–5.5)n.s.
 NRS score at activity 12–24 hours, median (IQR)3.25 (2.0–5.0)4.0 (3.0–5.5)n.s.
 NRS score max at PCA pump 0–6 hours, median (IQR)3.5 (0.0–4.0)5.0 (4.0–6.0)<0.002*
 NRS score max at PCA pump 6–12 hours, median (IQR)4.5 (0.0–6.0)5.0 (3.0–6.0)n.s.
 NRS score max at PCA pump 12–18 hours, median (IQR)4.0 (0.0–5.0)4.0 (0.0–5.0)n.s.
 NRS score max at PCA pump 18–24 hours, median (IQR)3.0 (0.0–4.0)3.0 (0.0–4.0)n.s.
 Time to first opioid in hours, mean (SD)4.0 (2.5)5.6 (3.3)<0.03
 Nausea/vomiting, n3/09/0n.s.
 Time to ambulation in hours, mean (SD)4.7 (3.1)4.6 (1.8)n.s.
 Time to sitting up in bed in hours, mean (SD)4.2 (3.0)4.3 (1.9)n.s.

  • The highest recorded NRS value in each 6-hour period was registered.

  • *When adjusting the p value with a factor 4 due to repeated measures (Bonferroni correction) in the six hourly intervals, differences between groups in regard to NRS pain scores in the first 6 hours continue to be statistically significant.

  • BMI, body mass index; NRS, numerical rating scale; PCA, patient-controlled analgesia; n.s., not significant.