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volume of local anaesthetic was given, the concentration required to produce effective motor
blockade decreased as patient age increased (Li et al, 2006 Level III‐1). Combinations of a local
anaesthetic and opioid are commonly used for epidural analgesia so it would seem reasonable
to use lower infusion rates in older patients (Macintyre & Upton, 2008).
Older patients may be more susceptible to some of the adverse effects of epidural analgesia,
including hypotension (Crawford et al, 1996; Simon et al, 2002; Veering, 2006).

11.2.7 Intrathecal opioid analgesia
Intrathecal morphine using a variety of doses provided more effective pain relief after major
surgery compared with other opioid analgesia, although the risk of respiratory depression and
pruritus was greater (Meylan et al, 2009 Level I). Advanced patient age is considered by some to
be a risk factor for respiratory depression and it has been suggested that patients over the age
of 70 years be monitored in an intensive care setting (Gwirtz et al, 1999 Level IV). However,
others report that older patients (average age 69 years) given up to 200 mcg intrathecal
morphine at the time of spinal anaesthesia for peripheral vascular and other surgery have
been safely nursed on general wards by nursing staff who have received additional education
and managed by an acute pain service (APS) according to strict guidelines (Lim & Macintyre,
2006 Level IV).
The ‘optimal’ dose of intrathecal morphine that should be given to older patients remains
unknown and any evidence for the ‘best’ dose remains inconsistent. Intrathecal morphine
doses of 200 mcg given in addition to general anaesthesia in older patients (average age
70 years) undergoing abdominal aortic surgery led to better postoperative analgesia and
reduced postoperative analgesia requirements compared with those given general
anaesthesia only; no conclusion could be made about adverse effects as total patients
numbers were small (Blay et al, 2006 Level II).
A comparison of three doses of intrathecal morphine (50 mcg, 100 mcg and 200 mcg) given to
older patients after hip surgery concluded that the 100 mcg dose provided the best balance
between good pain relief and pruritus; there was no difference seen in the incidences of
nausea and vomiting or respiratory depression (Murphy et al, 2003 Level II).
Use of intrathecal morphine in addition to IV PCA morphine after colorectal surgery led to
better pain relief and lower PCA morphine requirements compared with PCA morphine alone,
but sedation was increased and there were no differences in time to ambulation, duration of
hospital stay or incidence of confusion (Beaussier et al, 2006 Level II).
CHAPTER 11 Possible advantages of regional blockade in older patients include a reduction in the incidence
Other regional analgesia
11.2.8

of side effects compared with central neuraxial blockade (Zaric et al, 2006 Level II). Patient
outcome may also be improved when older patients receive regional rather than opioid
analgesia after surgery. After fixation of a fractured hip, those who received patient‐controlled
femoral nerve analgesia in addition to regular paracetamol and metamizol were less likely to
develop postoperative delirium, were able to sit at the bedside at an earlier stage, and
required no SC morphine compared with those given just paracetamol and metamizol, 28% of
whom required additional morphine analgesia (Rosario et al, 2008 Level IV).
The duration of action of sciatic nerve (Hanks et al, 2006 Level III‐2) and brachial plexus blocks
(Paqueron et al, 2002 Level III‐2) is prolonged in the older patient.
In older (greater than 65 years of age) patients undergoing urological surgery via a flank
incision, paravertebral blockade of the lumbar plexus using either ropivacaine or bupivacaine

406 Acute Pain Management: Scientific Evidence