Postoperative Pain Management

Core Multimodal Analgesic Regimen

The American College of Surgeons recommends postoperative pain management should be built on a foundation of multimodal analgesia combining acetaminophen with NSAIDs, administered pre-operatively or intra-operatively and continued postoperatively, with opioids strictly reserved as rescue medication only when non-opioid therapy fails 1
Acetaminophen 1g every 6 hours should be initiated at the beginning of postoperative analgesia as it is safer than other drugs and forms the cornerstone of pain management 1
NSAIDs should be added when not contraindicated for moderate pain and to reduce morphine consumption and related side effects 1
A single intra-operative dose of dexamethasone 8-10 mg IV is strongly recommended for its analgesic and anti-emetic effects 1

Oral administration should be preferred over intravenous route whenever feasible and drug absorption can be reasonably warranted 2
The intramuscular route must be avoided in postoperative pain management 2

Epidural and regional anesthesia is recommended in emergency general surgery whenever feasible and if not delaying emergency procedures 1
Single-shot fascia iliaca block or local infiltration analgesia is recommended, especially with contraindications to basic analgesics or in patients with high expected postoperative pain 1
Patients with neuraxial anesthesia must be monitored and assessed adequately 1
Neuraxial administration of magnesium, benzodiazepines, neostigmine, tramadol, and ketamine should be avoided 1

Opioids should be reserved strictly as rescue analgesics in the postoperative period, not as first-line therapy 1
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 1
Avoid initial infusion of opioids via PCA in opioid-naïve patients 3

Small doses of ketamine (maximum 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 1
Gabapentinoids can be considered as a component in multimodal analgesia, though systematic preoperative use is not recommended 1
Coxib administration may be considered if there are no contraindications 1

Postoperative pain assessment at rest and on movement is strongly recommended using validated pain scales (numeric rating scale 0-10) to improve patient management 4
After a pain intervention, reassess patients for both pain control and adverse reactions at appropriate intervals 1
A sudden increase in pain, especially with tachycardia, hypotension, or hyperthermia, requires urgent comprehensive assessment as this may herald postoperative complications (bleeding, anastomotic leaks, deep vein thrombosis) 5

Emergency general surgery is associated with more severe postoperative pain than elective surgery; specific attention should be given to this patient group 4
Reduce opioid use as much as possible to prevent cardiopulmonary complications in patients with obstructive sleep apnea syndrome 1

NSAIDs should be used cautiously in patients with colon or rectal anastomoses due to potential correlation with dehiscence and wound healing inhibition 1
Renal insufficiency (creatinine clearance <50 mL/min) is a contraindication to NSAIDs 6
Avoid combining coxibs and NSAIDs as their combination increases myocardial infarction incidence and affects kidney function 1

Adequate education for the patient and family about surgical and anesthesiologic treatment, options, plan, and aims of pain management should be performed whenever possible 4

Uncontrolled postoperative pain leads to tachycardia, arterial hypertension, increased abdominal wall and chest muscle rigidity, resulting in altered ventilation, hypoxemia, difficulties coughing, and increased risk of respiratory infectious complications 5