Postoperative Pain Management Guidelines
Basic Analgesic Regimen
- The foundation of postoperative pain management should include a combination of acetaminophen and NSAIDs or COX-2 selective inhibitors, administered pre-operatively or intra-operatively and continued postoperatively 1, 2
- Acetaminophen should be administered at the beginning of postoperative analgesia as it is better and safer than other drugs, with typical dosing of 1g every 6 hours 3, 4
- NSAIDs (when not contraindicated) should be used for moderate pain when used alone, and in multimodal analgesia to reduce morphine consumption and related side effects 3, 5
- A single intra-operative dose of intravenous dexamethasone 8-10 mg is recommended for its analgesic and anti-emetic effects 1, 2
Regional Analgesia Techniques
- Epidural and regional anesthesia is recommended in emergency general surgery, whenever feasible and if not delaying emergency procedures 6
- Single-shot fascia iliaca block or local infiltration analgesia is recommended, especially if there are contraindications to basic analgesics and/or in patients with high expected postoperative pain 1, 2
- Patients with neuraxial anesthesia must be monitored and assessed adequately 6
Opioid Management
- Opioids should be reserved as rescue analgesics in the postoperative period 1, 2
- Patient-controlled analgesia (PCA) is recommended when IV route is needed in patients with adequate cognitive functions, starting with bolus injection in opioid naïve patients 3, 6
- The intramuscular route should be avoided in postoperative pain management 6
Adjuvant Medications
- Small doses of ketamine (maximum dose of 0.5 mg/kg/h after anesthesia induction) are recommended in surgeries with high risk of acute pain or chronic postoperative pain, and in patients with vulnerability to pain 7
- Gabapentinoids can be considered as a component in multimodal analgesia, though systematic preoperative use is not recommended 3, 7
- Coxib administration may be considered if there are no contraindications 5, 4
Special Considerations
- For patients with obstructive sleep apnea syndrome (OSAS), reduce opioid use as much as possible to prevent possible cardiopulmonary complications 5, 8
- Be aware that younger age and female gender could be risk factors for acute postoperative pain 5, 8
Monitoring and Assessment
- Regular assessment of pain using validated pain scales is essential 5, 4
- After a pain intervention is completed, reassess patients for both pain control and adverse reactions at appropriate intervals 5, 4
- A combined nurse service with clinician supervision provides better outcomes in acute postoperative pain management 5, 8
- When a significant change in worsening pain level is reported, reevaluate the patient for possible postoperative complications 5, 4
Common Pitfalls and Caveats
- NSAIDs should be used cautiously in patients with colon or rectal anastomoses due to potential correlation with dehiscence and wound healing inhibition 3
- Avoid exceeding maximum toxic doses of local anesthetics, particularly for peri-prosthetic orthopedic infiltrations 7
- Neuraxial administration of magnesium, benzodiazepines, neostigmine, tramadol, and ketamine should be avoided 6
- Caution is needed when using acetaminophen in patients with liver disease 3
- Avoid combining coxibs and NSAIDs as their combination seems to increase the incidence of myocardial infarction and affects kidney function 9
Multimodal Approach to Postoperative Pain Management
Basic Analgesic Regimen
- A combination of two non-opioid drugs (NSAID and acetaminophen) should always be used to reduce the need for opioid rescue analgesics, as recommended by the Anaesthesia society 10
Regional Anesthesia Techniques
- Landmark-based or ultrasound-guided caudal block with long-acting local anesthetics can be used for lower extremity or abdominal procedures, as part of multimodal analgesia, according to the Anaesthesia society 10
- Brachial plexus blocks with long-acting local anesthetics can be used for upper extremity procedures, as part of multimodal analgesia, according to the Anaesthesia society 10
Opioid Management
- For breakthrough pain in PACU (Post-Anesthesia Care Unit), intravenous fentanyl or other suitable agents can be used, as recommended by the Anaesthesia society 10
- On the ward, consider oral or intravenous tramadol or nalbuphine as rescue medications, as recommended by the Anaesthesia society 10
Adjuvant Medications
- Glucocorticoids, such as dexamethasone 10 mg, have shown benefit in postoperative pain outcomes, reducing pain scores, opioid consumption, and enabling earlier ambulation, according to the Anaesthesia society 11
Special Considerations
Pediatric Patients
- For pediatric patients, ibuprofen can be dosed at 10 mg/kg every 8 hours, as recommended by the Anaesthesia society 10
- For pediatric patients, diclofenac can be dosed at 1 mg/kg every 8 hours, as recommended by the Anaesthesia society 10
- For pediatric patients, paracetamol can be dosed at 15 mg/kg every 6 hours, with a maximum daily dose of 60 mg/kg, as recommended by the Anaesthesia society 10