theatre and surgery
Optimal analgesia for
major open surgery
This article aims to explore the various modalities available for providing analgesia for major
open abdominal surgery and the evidence surrounding their use, risks and benefits
Ben L Morrison MBBS
BSc (Hons) FRCA
Clinical Fellow in
Anaesthesia for Major
Oncological Surgery
William J Fawcett MBBS
FRCA FFPMRCA
Consultant in
Anaesthesia and Pain
Medicine, Department
of Anaesthesia, Royal
Surrey County Hospital
Foundation Trust, UK
Effective analgesia after major surgery is not only
a humanitarian requirement, but is regarded as
fundamental to the overall anaesthetic process,
having a key role in achieving the best patient
outcomes. The adoption of multimodal analgesia,
since its description in 1993, 1 was driven by the
need to avoid both the short-term effects of opioids
and mitigate against the possible impact they may
have on longer-term intrinsic immunological
mechanisms protecting against infection and
long-term cancer growth and recurrence. Opioid-
sparing analgesia also facilitates early mobilisation
and enteral feeding with subsequent early return
of bowel function. Optimising analgesia is
recognised as a key component of an effective
enhanced recovery after surgery (ERAS)
programme, which by reducing the surgical stress
response, allowing early mobilisation and return to
normal gut function, has led to improvements in
outcomes for a number of surgical specialties
worldwide, especially colorectal surgery. 2
Furthermore, the concept of ‘procedure-specific
analgesia’ is fundamental as it can be unwise to
extrapolate analgesic techniques from one surgical
procedure to another.
To achieve effective opioid-sparing analgesia
several other treatment of modalities have been
described including:
• Local anaesthetic nerve blockade
• Systemic analgesics
• Non-analgesic methods (such as
acupuncture, transcutaneous electrical nerve
stimulation (TENS) and hypnosis) The last method
is outside the scope of this article and is not
considered further.
Opioid analgesia
Opioid use remains widespread despite well-known
adverse effects including sedation, respiratory and
cough depression, dysphoria, post-operative nausea
and vomiting (PONV), a delayed return to normal
gastrointestinal (GI) function and urinary
retention. More recently there has been a focus on
other issues surrounding perioperative opioid use
such as tolerance, opioid-induced hyperalgesia and
the immunosuppressive effects of opioids. 3,4
There is no doubt that opioids are very effective
analgesics and should not be withheld from
patients if other methods provide inadequate
analgesia. Indeed, the use of opioids in the
immediate post-operative period probably has little
deleterious effect. The aim should not be total
avoidance but conscientious use as part of
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a multi-modal approach. 1 There remains an
important role for opioids in patient-controlled
analgesia (PCA), particularly in patients for whom
regional analgesia may not be possible. Patients
must have a satisfactory pain score prior to
commencing PCA to achieve adequate effect.
Patient education remains an important aspect of
opioid use. The prolonged use of opioids should be
avoided and increased doses may be required for
patients already using regular opioids. The use of
opioids is not restricted to systemic use but
commonly as an adjunct to epidural and
intrathecal techniques.
Morphine is considered the gold-standard
opioid, with others such as codeine and tramadol
frequently used. Codeine is renowned for causing
constipation and its variable metabolism should
be considered in certain populations such as
paediatrics. 5 Tramadol has effects on opioid
receptors alongside inhibition of serotonin and
noradrenaline reuptake. This results in effective
analgesia but is also causes side effects that