Anaesthesia | Pain | Multi-modal Analgesia

Multi-modal Analgesia
Session Overview
Description
This session describes the optimization of pain control through the rational combination of drug and non-drug modalities.

Learning Objectives
By the end of this session you will be able to:

• Outline a rational strategy for analgesic drug combinations
• List examples of mixed pains which require the combined use of nociceptive and neuropathic analgesics
• Identify the differences between additive and synergistic analgesia
• List examples of enhanced drug interactions and side effects
• List conditions and their non-drug therapies that can optimize analgesia and function

Prerequisites
Before commencing this session you should:

• Be familiar with the pharmacology of WHO analgesia drugs and neuropathic adjuvants
• Be familiar with the recognition of nociceptive and neuropathic pains

The processing of nociception involves multiple neural pathways, transmitters and receptors. This suggests that there will never be a single ‘magic bullet’ analgesic agent or therapy. Optimum pain control therefore requires a multi-modal approach using several analgesic therapies.

Complete analgesia for severe pain is unlikely to occur, with the most realistic result being 50 % pain relief and this is the most commonly used end point in analgesic drug trials. Partial analgesia can be further improved by the addition of a second analgesic which acts by a different mechanism to the first drug.

Number needed to treat (NNT) can be maintained or improved with lower doses of the individual drugs, with a possible improvement in side effect profile.