1. Pain assessment - acute vs chronic pain, pain scales, reassessment
2. Physiology of surgical pain - nociception, stress response, sensitization
3. Preoperative planning - risk assessment, informed expectations, opioid use history
4. Pharmacological analgesia - paracetamol, NSAIDs, opioids, ketamine, local anaesthetics, adjuvants
5. Regional and neuraxial techniques - wound infiltration, peripheral nerve blocks, epidural and spinal analgesia
6. Multimodal analgesia and ERAS - opioid-sparing combinations and early recovery
7. Postoperative pain management - PCA, monitoring, complications, discharge analgesia
8. Special situations - children, older adults, pregnancy, renal/hepatic impairment, opioid tolerance and chronic pain
9. Complications and safety - respiratory depression, nausea/vomiting, constipation, NSAID risks, local anaesthetic toxicity
10. Chronic postsurgical pain - prevention and recognition

1. Pain assessment - acute vs chronic pain, pain scales, reassessment
2. Physiology of surgical pain - nociception, stress response, sensitization
3. Preoperative planning - risk assessment, informed expectations, opioid use history
4. Pharmacological analgesia - paracetamol, NSAIDs, opioids, ketamine, local anaesthetics, adjuvants
5. Regional and neuraxial techniques - wound infiltration, peripheral nerve blocks, epidural and spinal analgesia
6. Multimodal analgesia and ERAS - opioid-sparing combinations and early recovery
7. Postoperative pain management - PCA, monitoring, complications, discharge analgesia
8. Special situations - children, older adults, pregnancy, renal/hepatic impairment, opioid tolerance and chronic pain
9. Complications and safety - respiratory depression, nausea/vomiting, constipation, NSAID risks, local anaesthetic toxicity
10. Chronic postsurgical pain - prevention and recognition

• Full concise surgery notes
• Drugs and usual perioperative doses
• Regional analgesia techniques
• Postoperative pain management
• Exam short notes and viva questions

Surgical Pain Management - Concise Exam Notes

Definition and importance

1. Assessment of pain

• Assess preoperatively: previous analgesic use, opioid tolerance, chronic pain, substance use, renal/hepatic disease, respiratory disease, bleeding risk, allergies, and patient expectations.
• Measure pain repeatedly using:
  • Visual analogue scale (VAS)
  • Numeric rating scale (NRS 0-10)
  • Verbal rating scale
  • Behavioural scales in non-communicative patients
• Assess pain at rest and on movement/coughing.
• Record sedation level, respiratory rate, oxygenation, nausea/vomiting, bowel function, and analgesic adverse effects.

2. Principles of management

1. Treat pain early and reassess regularly.
2. Use an individualized plan based on patient, procedure, and comorbidity.
3. Prefer multimodal analgesia.
4. Use regional anaesthesia where appropriate.
5. Use opioids for rescue or moderate-severe pain, not as the only strategy.
6. Combine analgesia with non-drug measures and early mobilization.
7. Ensure safe monitoring, particularly after opioids or neuraxial analgesia.

3. Multimodal analgesic regimen

4. Opioid analgesia

• Opioids act mainly through mu receptors in the central nervous system.
• Routes: oral, IV, subcutaneous, intrathecal, or epidural.
• IV opioids are useful when oral intake is not possible or pain is severe; convert to oral medication when stable and tolerating diet.
• Avoid routine intramuscular injections because absorption is unpredictable and injections are painful.
• Use the lowest effective dose for the shortest period.

Common complications

• Respiratory depression
• Excess sedation
• Nausea and vomiting
• Constipation / ileus
• Urinary retention
• Pruritus
• Delirium, especially in older adults
• Tolerance, dependence, and opioid-induced hyperalgesia

Management of opioid adverse effects

• Reduce dose or stop opioid where appropriate.
• Add or optimize non-opioid and regional analgesia.
• Give antiemetic for nausea/vomiting.
• Prescribe bowel regimen if opioids continue.
• If respiratory depression occurs: airway support, oxygen, close monitoring, and titrated naloxone when clinically indicated.

5. Patient-controlled analgesia (PCA)

Advantages

• Timely analgesia
• Reduces delay in nurse-administered doses
• Patient autonomy
• Avoids repeated IM injections

Safety points

• Only the patient should press the PCA button. Do not permit “PCA by proxy.”
• Review demand dose, lockout interval, total dose received, unsuccessful demands, sedation, respiratory rate, and oxygenation.
• Avoid or use specialist supervision for background infusions in opioid-naive or high-risk patients.

6. Regional and neuraxial analgesia

A. Local infiltration and wound catheters

• Local anaesthetic infiltrated into incision or delivered through catheter.
• Simple and opioid-sparing.
• Useful for minor to moderate procedures.

B. Peripheral nerve blocks

• Examples: brachial plexus block, femoral/adductor canal block, fascia iliaca block, TAP block, paravertebral block.
• Provide site-specific analgesia and reduce systemic opioid need.
• Can be single shot or continuous catheter infusion.

C. Epidural analgesia

• Local anaesthetic with or without opioid through an epidural catheter.
• Especially useful after major thoracic, upper abdominal, and major lower-limb surgery.
• Produces superior dynamic analgesia compared with systemic opioid therapy in suitable patients.

7. Non-pharmacological measures

• Preoperative counselling and realistic expectations
• Reassurance and communication
• Positioning and splintage of incision during coughing
• Ice or heat where appropriate
• Physiotherapy, breathing exercises, and early mobilization
• Relaxation, distraction, music, and sleep support

8. Enhanced Recovery After Surgery (ERAS)

• Preoperative counselling and optimization
• Non-opioid baseline analgesia where appropriate
• Regional/local techniques
• Minimal effective opioid use
• Prevention of postoperative nausea and vomiting
• Early feeding, mobilization, and removal of tubes/drains where appropriate

9. Special situations

Elderly

• Start with lower doses and titrate carefully.
• Higher risk of delirium, falls, renal impairment, and respiratory depression.
• Avoid excessive sedation.

Renal impairment

• Avoid or limit NSAIDs.
• Some opioids and active metabolites accumulate, so choose and dose carefully.

Hepatic impairment

• Reduce paracetamol total dose.
• Use opioids cautiously due to impaired metabolism.

Opioid-tolerant patient

• Continue baseline opioid requirement where feasible.
• Expect higher postoperative analgesic needs.
• Plan early with acute pain or anaesthesia team.
• Use strong multimodal and regional techniques.

Obstructive sleep apnoea / respiratory disease

• Minimize opioids and sedatives.
• Prefer regional techniques and enhanced monitoring.

10. Chronic postsurgical pain

Risk factors

• Severe acute postoperative pain
• Nerve injury
• Pre-existing pain
• Anxiety/depression
• Younger age
• Opioid use before surgery

Prevention

• Good acute pain control
• Multimodal analgesia
• Avoid unnecessary nerve injury
• Identify and refer persistent neuropathic pain early

Short exam answer: “Outline postoperative pain management”