PCA

• Patient-Controlled Analgesia (PCA)


  An effective method of pain relief that gives the patient a sense of control over their pain
• How PCA works


  1. A needle attached to an IV line is placed into a vein

  2. A computerized pump lets the patient release pain medicine by pressing a handheld button
• PCA pump

  • A computerized machine that gives the patient medicine for pain when they press a button
  • Usually supplies opioid pain-controlling medicines like morphine, fentanyl and hydromorphone
  • Medicine is usually delivered only when the patient presses the button (bolus), but a continuous rate may be added by the doctor if needed (basal rate)
• Indications for PCA

  • Major operation
  • Marked incident pain
  • Cancer pain
• Advantages of PCA


  • Patients can titrate their analgesia to their pain
  • Patients are in "control"
  • Rapid response to demand for analgesia
  • Reduced patient anxiety compared with other analgesia techniques
  • Fewer complications when opioids are administered this way
  • Excellent analgesia for the majority of patients
  • Increased staff, patient and family satisfaction
  • Decreased staff workload
• Safety factors for PCA


  • PCA is safer than IM or IV opioid boluses
  • The patient should be the only person to use the handset/button
  • The PCA should be set up and supervised by experienced staff
  • The PCA program should be standardised according to a fixed protocol to eliminate error
• Routes of administration for PCA

  • Intravenous
  • Intramuscular
  • Subcutaneous
  • Epidural
• Components of a PCA system


  • A pump with an accuracy of at least ±5% of the programmed dose
  • The remote demand button connected to the pump and activated by the patient
  • An anti-siphon and backflow valve

  
• Bolus dose


  • When the patient presses the remote button, the PCA delivers the programmed bolus dose
  • In cases of severe pain or in patients with large opioid requirements the bolus dose may be several times higher than the usual protocol
• Lockout time


  • Lockout time is usually set at 5 minutes
  • The PCA will not deliver a dose during lockout time, even if the patient presses the button
  • This allows each bolus to reach peak effect before the patient has another bolus
  • Lockout time reduces the risk of overdose
• Good tries / Bad tries

  • A good try is when the PCA delivers a bolus dose of analgesia
  • A bad try is when the patient presses the button during the lockout time and no bolus dose is delivered
  • Knowing the proportion of good and bad tries allows to adjust the PCA settings to meet the patient's needs or whether further patient education is required
• Dose duration


  • Dose duration is normally set as 'stat'
  • Alaris PCA 'stat' is 70 seconds
  • The dose duration may be increased to prevent problems such as light-headedness or nausea associated with a rapid peak of onset of analgesia
• Patient selection for PCA


  • Surgical
  • Medical
  • Trauma
  • Burns
  • Oncology
• Contraindications to PCA


  • Inability to understand the concept of PCA
  • Children not wishing to control their own analgesia
• Problems in practice and safety features


  • The ability of the patient to co-operate and understand is essential
  • Availability of trained staff to program the device and monitor the patient is vital
  • In the PCA mode, the patient may awaken in severe pain because no boluses were administered during sleep
  • Some PCA devices require special giving sets and syringes
  • Technical errors can be fatal