Prehospital Analgesia Dr David Teubner 20/7/5

What is pain? Pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage. IASP 1986

Types of pain Lots of different calssifications Acute vs chronic

Acute pain Cause is known Temporary (< 6 weeks) Located in area of trauma Resolves spontaneously

Chronic pain Untreated pain may lead to neuronal changes which alter pain sensation and lead to chronic pain

History of prehospital analgesia US army ambulances in the 1860’s carried brandy for pain relief Even today there is very little scientific evidence for any of the techniques used

Analgesia myths No diagnosis = no analgesia Analgesia masks clinical signs We do a good job in providing analgesia Any dose of morphine will provide pain relief Analgesia causes dependence Analgesia causes adverse events

Time to analgesia Oligoanalgesia well recognised in EDs Frequent source of patient complaint

Assessment of pain Pain is unique to the individual, it is influenced by Age Race Gender Culture Emotional/cognitive state Prior experience

Measurement of pain Visual analogue scales Numerical rating scale Verbal or adjective rating scale (VRS/ARS): none, mild, moderate, severe, or unbearable.

Management of pain Non pharmacological Drugs –Methoxyflurane –Morphine

Non–pharmacological management Management of the underlying condition –Splinting fractures –Positioning Reassurance Others –Cognitive (guided imagery, music, distraction) –Behavioural (relaxation, breathing, biofeedback)

Morphine history Naturally derived from the opium poppy – Papaver somniferum Opium first used in about 4000 BC First medical use in 200 BC In the 16 th century Paracelcus called it laudanum (from latin laudare – to praise) First isolated in 1803 by Serturner who called it morphia. Now called morphine instead as most plant alkaloids end in “-ine”

Morphine Narcotic Opiod analgesic Bind to Opiod receptors to cause analgesia, euphoria, sedation, and respiratory/physical depression Stimulates emetic chemoreceptors. Peripheral vasodilitation and inhibition of baroreceptors. Histamine release is common 2-20 mg IV  Paeds mg/kg

Morphine indications Pain –Musculoskeletal –Chest –Abdominal

Contraindications Known allergy

Morphine - precautions Prepare to manage hypotension and respiratory depression -use w/ caution in COPD and Asthma Inhibits peristalsis Rapid injection increases incidence of adverse reactions Headache

Questions?