Multimodal analgesia

What it means (core concept)

• Multimodal analgesia = using 2 or more analgesic techniques/drugs that work by different mechanisms.
• Aim: better pain relief with fewer opioid-related problems (nausea, sedation, respiratory depression, ileus, urinary retention, delirium).
• Think in layers: baseline simple analgesics + targeted regional/local techniques + opioids only as needed (rescue).
• Choose options based on surgery type, patient factors (renal/liver function, asthma, bleeding risk), and expected pain severity.

Why it matters on day 1

• Most post-op pain plans should include regular paracetamol unless contraindicated.
• NSAIDs can be very effective opioid-sparing drugs but need basic safety checks (kidneys, bleeding risk, asthma history, GI risk).
• Regional anaesthesia and local infiltration can dramatically reduce opioid needs—know what’s been done (block type, local anaesthetic dose, catheter).
• Good analgesia supports early mobilisation, breathing/coughing, and reduced complications.

Common building blocks (practical overview)

• Paracetamol: regular dosing is a foundation; check total daily dose and liver disease/alcohol excess risk.
• NSAIDs (e.g., ibuprofen/naproxen/diclofenac/ketorolac): strong for inflammatory pain; avoid or use cautiously in renal impairment, active bleeding/high bleeding risk, peptic ulcer disease, severe heart failure, and some asthma patients.
• Opioids (e.g., morphine/oxycodone/fentanyl): use the lowest effective dose; plan for side effects (antiemetic, laxative if ongoing).
• Local anaesthetic techniques: wound infiltration, surgeon-delivered local, fascial plane blocks, neuraxial (spinal/epidural).
• Adjuncts in selected patients: gabapentinoids (limited routine role due to sedation/dizziness), ketamine (opioid-tolerant or severe pain), alpha-2 agonists (specialist use), lidocaine infusion (selected cases).
• Non-drug measures: reassurance, positioning, splinting wounds, ice/heat when appropriate, early physiotherapy.

A simple approach to prescribing (safe starter template)

• Step 1: Regular baseline analgesia: paracetamol (unless contraindicated).
• Step 2: Add an NSAID if appropriate and not contraindicated; document reason if omitted.
• Step 3: PRN opioid for breakthrough pain (start low, reassess effect and sedation).
• Step 4: If moderate–severe pain expected: consider regional/local techniques early (pre-op or intra-op) and plan post-op follow-up.
• Step 5: Anticipate side effects: antiemetic PRN; laxative if opioids likely >24–48 h; consider urinary retention risk.
• Step 6: Reassess regularly: pain score at rest and on movement, sedation score, respiratory rate, nausea, itch, and function (deep breath/cough/mobilise).

First-time scenarios you will meet

• PACU patient in pain despite opioids: check surgical site, block status, timing of last analgesics, and consider non-opioid options; avoid repeated opioid boluses if sedation/respiratory rate is falling.
• Patient with CKD: paracetamol usually OK; avoid NSAIDs; opioid doses may need reduction (risk of accumulation); seek senior advice for alternatives.
• Elderly/frail: higher sensitivity to opioids and gabapentinoids; prioritise regional techniques and simple analgesics; use small opioid doses with close monitoring.
• Asthma history: NSAIDs may trigger bronchospasm in some; clarify previous NSAID tolerance; avoid if history of NSAID-exacerbated respiratory disease.
• Anticoagulated patient: neuraxial and some deep blocks may be contraindicated; check local guidelines and timing of anticoagulants; consider superficial blocks/local infiltration instead.
• Opioid-tolerant patient: expect higher requirements; continue baseline opioid where appropriate; consider ketamine/regional techniques; involve acute pain team early.

Monitoring and documentation (what good looks like)

• Document: pain plan, what was given, what regional technique was performed, and any limits (e.g., avoid NSAIDs).
• Use a structured assessment: pain score (rest/movement), sedation score, respiratory rate, oxygen requirement, nausea/vomiting, itch, and ability to mobilise/breathe deeply.
• Escalate early if pain is severe, rapidly worsening, or out of keeping with expected post-op course.