Postoperative pain

Background

Acute pain is common after surgery, and for many it will be moderate or severe
Postoperative pain is associated with poor clinical outcomes, patient dissatisfaction, and long-term morbidity including chronic pain
Normal healing can take up to 3 months; pain lasting beyond this time is assumed to be pathologic

Typical postoperative pain is nociceptive, well-localized, described as sharp, aching, or throbbing

Results in decreases in quality of life, sleep, physical activities, and mental status
May result in chronic pain

Regional or neuraxial anaesthetic is preferred for those at high risk of postoperative pain
Intraoperative lidocaine or ketamine infusions can be considered

First-line: acetaminophen 500 to 1000 mg PO q6h for 3 to 5 days, plus one of:
- Celecoxib 100 to 200 PO bid for 3 to 5 days, or
- Ibuprofen 200 to 800 mg PO bid for 3 to 5 days, or
- Naproxen 250 to 500 mg PO bid for 3 to 5 days
If NPO: acetaminophen 1000 mg IV q6h (if available) for 3 to 5 days plus ketorolac 15 mg IV q8h for 3 days
As well as one of the following:
- Oxycodone 5 to 10 mg PO q4h prn
- Hydromorphone 1 to 2 mg PO q4h prn
- Morphine 5 to 15 mg PO q4h prn

Standing acetaminophen and NSAIDs, if possible
Consider patient-controlled anaesthesia (PCA)
Consider postoperative regional anaesthetic
Consider intravenous ketamine
- Intermittent infusion: 0.1 mg/kg IV q4h, titrated to maximum dose of 0.35 mg/kg
- Continuous infusion: 0.1 mg/kg/h IV continuous infusion, titrated to maximum dose 0.25 mg/kg/h
Consider lidocaine infusion
Consider cannabinoids
Consider gabapentinoids