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Key messages
1. Intravenous opioid PCA provides better analgesia than conventional parenteral opioid
regimens (S) (Level I [Cochrane review]).
2. Opioid administration by intravenous PCA leads to higher opioid consumption (R), a higher
incidence of pruritus (R), and no difference in other opioid‐related adverse effects (S) or
hospital stay (S) compared with traditional methods of intermittent parenteral opioid
administration (Level I [Cochrane review]).
3. In settings where there are high nurse‐patient ratios there may be no difference in
effectiveness of PCA and conventional parenteral opioid regimens (N) (Level I).
4. Patient preference for intravenous PCA is higher when compared with conventional
regimens (U) (Level I).
5. The addition of ketamine to PCA morphine does not improve analgesia or reduce the
incidence of opioid‐related side effects (U) (Level I).

6. Iontophoretic fentanyl PCA may not be as effective as intravenous morphine PCA, with
more patients withdrawing from studies because of inadequate pain relief (Level I).
7. There is little evidence that one opioid via PCA is superior to another with regards to
analgesic or adverse effects in general; although on an individual patient basis, one opioid
may be better tolerated than another (U) (Level II).
8. There is no analgesic benefit in adding naloxone to the PCA morphine solution; however in
ultra‐low doses the incidence of nausea and pruritus may be decreased (U) (Level II).
9. The addition of a background infusion to intravenous PCA does not improve pain relief or
sleep, or reduce the number of PCA demands (U) (Level II).
10. Subcutaneous PCA opioids can be as effective as intravenous PCA (U) (Level II).
11. Intranasal PCA opioids can be as effective as intravenous PCA (U) (Level II).
12. The risk of respiratory depression with PCA is increased when a background infusion is CHAPTER 7
used (U) (Level IV).
The following tick boxes  represent conclusions based on clinical experience and expert
opinion.

 Adequate analgesia needs to be obtained prior to commencement of PCA. Initial orders for
bolus doses should take into account individual patient factors such as a history of prior
opioid use and patient age. Individual PCA prescriptions may need to be adjusted (U).
 The routine addition of antiemetics to PCA opioids is not encouraged, as it is of no benefit
compared with selective administration (U).
 PCA infusion systems must incorporate antisyphon valves and in non‐dedicated lines,
antireflux valves (U).
 Drug concentrations should be standardised within institutions to reduce the chance of
programming errors (U).
 Operator error remains a common safety problem (N).

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