Pregabalin and dexamethasone for postoperative pain control: a randomized controlled study in hip arthroplasty

Background. Optimal pain treatment with minimal side-effects is essential for early mobility and recovery in patients undergoing total hip arthroplasty. We investigated the analgesic effect of pregabalin and dexamethasone in this surgical procedure. Methods. One hundred and twenty patients were randomly allocated to either Group A (placebo), Group B (pregabalin 300 mg), or Group C (pregabalin 300 mg+dexamethasone 8 mg). The medication and acetaminophen 1 g were given before operation. Spinal anaesthesia was performed. Postoperative pain treatment was with acetaminophen 1 g three times daily and patient-controlled i.v morphine, 2.5 mg bolus. Nausea was treated with ondansetron. Morphine consumption, pain intensity at rest and during mobilization, nausea and vomiting, sedation, dizziness, and consumption of ondansetron were recorded 2, 4, and 24 h after operation. P < 0.05 was considered statistically significant. Results. Twenty-four hour morphine consumption was significantly reduced in Groups B [mean (sd) 24 (14) mg] and C [25 (19) mg] compared with Group A [47 (28) mg]. Vomiting was reduced in Group C compared with Group B (P=0.03). Sedation was significantly increased in Group B compared with the other groups. Conclusions. Pregabalin resulted in a 50% reduction in 24 h postoperative morphine requirements. This was not associated with a reduced incidence of nausea or vomiting. Pregabalin resulted in increased levels of sedation. Combining pregabalin and dexamethasone provided no additional effects on pain or opioid requirements.