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Understanding Your Anaesthetic for Hip or Knee Replacement

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Understanding Your Anaesthetic for Hip or Knee Replacement

1. Types of Anaesthesia

  • Spinal Anaesthesia:
    • Injection into lower back, numbing lower body.
    • You remain awake and aware.
    • Estimated Time:
      • Injection: 5-10 minutes
      • Numbness duration: 2-4 hours
    • Further information: Refer to leaflet "Your Spinal Anaesthetic."
  • General Anaesthesia:
    • Induces a deep sleep-like state; you feel nothing.
    • Medication given through vein, inhaled, or combination.
    • Estimated Time:
      • Induction (falling asleep): 5-15 minutes
      • Total anaesthesia duration: Typically 2-5 hours (dependent on surgery)
  • Nerve Block:
    • Injection near nerves supplying leg, creating numbness and pain relief.
    • Requires a spinal or general anaesthetic in combination.
    • Estimated Time: Injection: 15-30 minutes. Pain relief duration: 12-24 hours.
    • Further information: Refer to leaflet on Peripheral nerve blocks.
  • Local Anaesthetic Infiltration (Wound Infiltration):
    • Injection around the joint during surgery to enhance post-operative comfort.
    • Can be used with spinal or general anaesthesia.
    • Estimated Time: Injection: 5-10 minutes.
  • Sedation:
    • Used with spinal anaesthesia to promote relaxation and sleepiness.
    • Levels range from light to deep; memory of the procedure may vary.
    • Estimated Time: Effects last approximately 30-60 minutes after the operation.
    • Further information: Refer to leaflet "Sedation Explained."

2. Preparing for Your Operation

  • Preoperative Assessment Clinic (Preassessment):
    • Purpose: Evaluate overall health, activity levels, and order necessary tests.
    • Estimated Time: Clinic visit: 60-90 minutes.
    • What to bring: List of medications or medicines in original packaging.
    • Topics covered: Health history, activity levels, allergies, anaesthesia options.
  • Improving Your Health Before Surgery:
    • Lifestyle changes can lead to quicker recovery and fewer complications.
    • Refer to leaflet on "Preparing for Your Surgery" for more information.

3. On the Day of Your Operation

  • Starting the Anaesthesia:
    • May occur in anaesthetic room or operating theatre.
    • Monitoring of heart rate, blood pressure, and oxygen levels.
    • Estimated Time: Preparation and monitoring setup: 15-30 minutes.
  • Cannula Insertion:
    • A thin tube inserted into a vein for medication administration.
    • Local anaesthetic cream may be used to numb the area if desired.
  • During the Operation:
    • Anaesthetist closely monitors your condition and adjusts anaesthesia as needed.
    • Communication is possible if you are awake or sedated.
  • After the Operation – Recovery Room:
    • Closely monitored for recovery from anaesthesia.
    • One-to-one care from healthcare professional.
    • Monitoring of vital signs and administration of pain relief and fluids.
    • Estimated Time: Recovery room stay: Typically 2-4 hours.
  • Pain Relief:
    • Focus on minimising pain after surgery.
    • Methods: Pills/tablets/liquids, injections.
    • Patient-Controlled Analgesia (PCA):
      • A system that allows you to administer small doses of pain medication through a pump, at intervals you choose (within pre-set limits).
      • A small tube (catheter) is placed in a vein, usually in your arm or leg.
      • The pump is programmed by your anaesthetist with a "background" infusion (a small, continuous dose) and a "patient-controlled" dose that you can press a button to request.
      • There is a lockout period between button presses to prevent over-medication.
      • PCA allows for more personalised pain management and can reduce the need for larger doses of medication.
      • Your nurse will explain how to use the PCA pump and answer any questions you have.
      • Important: Do not hesitate to ask your nurse for help or if you are experiencing pain.

4. Going Home and When to Seek Help

  • Discharge:
    • Dependent on recovery speed, health condition, surgery type, and anaesthesia.
    • Cannot drive after surgery; arrange transportation.
  • Follow-up:
    • Information provided on exercises and wound care.
  • When to Seek Help:
    • Severe or increasing pain.
    • Pain and swelling at surgical site.
    • Chest pain or breathing difficulty.
    • Fever.

5. Frequently Asked Questions (FAQ)

  • Q: What type of anaesthesia is best for me? A: Discussed with your anaesthetist based on your medical history and surgery specifics.
  • Q: Will I feel any pain during the procedure? A: No, with appropriate anaesthesia.
  • Q: How long will the effects of the anaesthesia last? A: Varies depending on the type of anaesthesia.
  • Q: What are the risks associated with anaesthesia? A: Discussed with your anaesthetist.
  • Q: What is PCA and how does it work? A: See the "Patient-Controlled Analgesia (PCA)" section above.

6. Glossary of Terms

  • Anaesthesia: Preventing pain and sensation.
  • Cannula: Thin tube inserted into a vein.
  • Epidural: Type of regional anaesthesia.
  • Induction: Process of putting a patient under general anaesthesia.
  • Nerve Block: Type of regional anaesthesia numbing a specific area.
  • Patient-Controlled Analgesia (PCA): System allowing patients to administer pain medication.
  • Regional Anaesthesia: Type of anaesthesia numbing a specific region.
  • Sedation: State of reduced awareness.