Unless they are contraindicated, non-opioid analgesics should always be used in the same way as for other patients when treating acute and postoperative pain, i.e. paracetamol and non-steroidal antiinflammatory drugs (NSAIDs). These medicines alone will most often provide adequate relief for moderate pain. Paracetamol is contraindicated in patients with acute hepatitis, while patients with moderate chronic liver affection can take paracetamol in normal therapeutic doses. A single dose of steroids can also provide better postoperative pain relief.
When treating moderate to severe pain, the choice is usually between treatment with opioids and regional anaesthesia/infiltration anaesthesia. Treatment with ketamine in sub-anaesthetic doses – for example 1 mg/kg/24 hours subcutaneously – may also be a possibility in special cases. In other patient populations, low-dosage ketamine has been found to have an opioid-saving effect with little risk of psychomimetic side effects (2). When using a catheter for epidural analgesia or for peripheral blockades, a continuous infusion or repeated doses of local anaesthetic can be given. Figure 1 shows an algorithm for the choice of postoperative pain treatment for OMT patients. If a regimen without opioids is chosen, it must be borne in mind that the patient still needs his/her usual substitution dose of opioid to avoid abstinence symptoms. If the route of administration for the substitution dose has to be changed, in most cases it will also be necessary to change the dose or the opioid.
When treating pain with opioids, using a pump with a combination of continuous infusion and bolus doses may be preferable to giving bolus doses alone. Medication from a pain pump can be given intravenously or as a subcutaneous infusion. Intravenous administration is easier to titrate, whereas subcutaneous infusion causes slower changes in the serum concentration and therefore presumably less sense of intoxication from the bolus doses.
Premedication with benzodiazepine or opioids should not routinely be given to OMT patients. Indications for premedication with benzodiazepine are intense anxiety and agitation. Several of the authors have experienced that the sedative effect of opioids can also be used to reduce anxiety and agitation before surgery. It is not clear how high the threshold should be for administering such premedication, but the majority of the authors support a restrictive policy.