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life in haemophilia patients; biopsychosocial assessment and treatment should be considered
(Wallny et al, 2001 Level IV).
Many haemophilia patients use Factor VIII to decrease pain associated with a bleeding episode
(Wallny et al, 2001 Level IV). Higher‐dose Factor VIII replacement reduced the number of
patients with restricted joint movement after an acute haemarthrosis (Aronstam et al, 1983,
Level II). Joint aspiration may reduce pain and improve joint function (Baker, 1992).
Although there is no good evidence available, opioids, simple analgesics, cold therapy and
bandaging have been used in treating acute pain associated with haemophilia. NsNSAIDS have
been used to provide analgesia in haemophilic arthropathy, but there are no data on their use
in acute haemarthrosis. Coxibs may be of benefit due to a lack of platelet inhibitory effects
(see Section 4.2). IM analgesics should be avoided due to the risk of bleeding.
The porphyrias
The acute porphyrias are a group of inherited disorders of haem biosynthesis. The most
common autosomal dominant forms are acute intermittent porphyria, variegate porphyria and
hereditary coproporphyria. The disorder of haem biosynthesis leads to accumulation of
neurotoxic aminolaevulinic acid (ALA) and porphyrin metabolites, which can result in
peripheral, visceral and autonomic neuropathies (eg clinical features might include motor
weakness, abdominal pain and tachycardia) as well as central nervous system (CNS) toxicity
(neuropsychiatric symptoms, seizures, brainstem and pituitary dysfunction); some patients
may have a cutaneous photosensitivity (Visser & Goucke, 2008).
Pain management in acute porphyria is based on treatment of the disease, including
resuscitation and supportive care, ceasing ‘triggers’, the early administration of hem arginate
(Herrick et al, 1989 Level II), and possibly high‐dose IV dextrose or cimetidine administration
('disease modifying agents') (Rogers, 1997).
Specific evidence for pain management in acute porphyria is limited. Analgesia is based largely
on the use of IV and (later) oral opioids (Anderson et al, 2005; Herrick & McColl, 2005). Opioids
such as pethidine (Deeg & Rajamani, 1990) or tramadol, and other ‘analgesics’ (such as tricyclic
antidepressants [TCAs]) that lower seizure threshold should be avoided in acute porphyria,
because of increased seizure risk.
The safety of nsNSAIDs or coxibs in acute porphyria has not been established; paracetamol,
buscopan (for colic) or N 2O in oxygen, are considered safe (Anderson et al, 2005; Stoelting &
Dierdorf, 1993). CHAPTER 9
There may be a place for IV low‐dose ketamine or regional analgesia, although the safety of
these approaches has not been established in acute porphyria. Ketamine does not induce ALA
synthetase in rats (Harrison et al, 1985) and has been used for anaesthesia in porphyria patients
without apparent problems (Capouet et al, 1987). However one case report noted increased
porphyrin levels in a patient after induction with ketamine (Kanbak, 1997).
As metoclopramide is contraindicated and the safety of 5HT3 antagonists is as yet unclear,
droperidol has been suggested as the antiemetic of choice in acute porphyria (Anderson et al,
2005).

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