Total Hip Arthroplasty 2019

Total hip arthroplasty-specific evidence

Data table: Paracetamol and NSAIDs/COX-2-selective inhibitors for pain management after THA

Arguments for…

• IV paracetamol was compared with placebo in two studies (Sinatra 2012; Takeda 2019), which showed lower pain intensity scores over the first 24 h and lower morphine consumption in the paracetamol groups.
• One study found no difference between IV and oral administration of paracetamol on postoperative pain outcomes (Westrich 2019).
• Paracetamol, anti-inflammatory drugs and placebo were recently compared in two studies (Camu 2017; Thybo 2019). When taken individually, both drugs improved postoperative pain outcomes, whereas parecoxib plus paracetamol did not improve pain scores over parecoxib alone in one study (Camu 2017), and paracetamol combined with ibuprofen did not result in a clinically relevant improvement over ibuprofen alone (Thybo 2019).
• Three studies showed analgesic benefit of NSAID administration vs placebo (Gombotz 2010; McQuay 2016; Moodie 2013).
  • Regular IV diclofenac and orphenadrine infusions after surgery and at 12 h reduced morphine PCA consumption postoperatively vs placebo (Gombotz 2010).
  • One study showed that a combination of oral dexketoprofen 25 mg with tramadol 75 mg was superior to both medications alone for postoperative pain control (McQuay 2016).
  • In a three-group study, ketorolac improved pain scores and morphine consumption compared with a novel protein kinase C-epsilon inhibitor and placebo (Moodie 2013).
• Three of four studies found benefits for postoperative pain with pre-incisional COX-2-selective inhibitor administration (Bao 2012; Renner 2012; Ittichaikulthol 2010; Peng 2018).
  • Two studies found that oral etoricoxib 2 h before surgery (Renner 2012), or IV parecoxib or oral celecoxib 1 h before surgery (Ittichaikulthol 2010) were associated with significantly lower postoperative pain scores and morphine consumption when compared with placebo.
  • These benefits were not found in another study with a 30-min pre-incisional IV parecoxib infusion (Peng 2018).
  • Another study directly compared 30-min pre- vs. 30-min post-incisional IV 40 mg parecoxib administration (Bao 2012) and found lower pain scores up to 6 h postoperatively and lower morphine consumption up to 24 h postoperatively with a pre-incisional protocol.
• A single study compared IV paracetamol with IV metamizole and found clinically insignificant reductions in morphine consumption and pain scores with metamizole (Oreskovic 2014), although pain scores in both groups were always lower than 40 mm on a VAS.

PROSPECT Recommendations

• The basic analgesic regimen should include the combination of paracetamol (Grade A) and an NSAID or a COX-2-selective inhibitor (Grade A) administered pre-operatively or intra-operatively and continued post-operatively.
  • The administration of paracetamol in combination with NSAID or COX-2-selective inhibitors is recommended unless contraindicated. Procedure-specific evidence suggests a limited impact of paracetamol when added to a regimen including COX-2-selective inhibitors or NSAIDs, but paracetamol is recommended as part of basic postoperative analgesia in general as side effects are minor.
  • There is insufficient evidence to determine whether pre-operative administration has an advantage over postoperative administration of COX-2-selective inhibitors.
  • There is no procedure-specific evidence to choose a specific NSAID or COX-2-selective inhibitor.