analgesics
Table of Contents
pain, analgesia and analgesics
see also anaesthetics
- Western Health policies (intranet only):
Mx of acute pain in the ED
- most analgesics have adverse effects, particularly as dose is increased
- ASK patient if they want more or any pain management - many will prefer to have some pain rather than excessive analgesics
- occult causes of pain (eg. HbS crises, sprained ankle with normal Xray) are often undertreated and thus staff may need to be aware of this tendency and give adequate relief.
- agitated demented patients usually benefit more from analgesics than sedatives - remember to look for causes of occult pain such as acute urinary retention
- propofol is NOT an analgesic, and use without analgesics for painful procedures may result in delayed post-traumatic stress type symptoms
- do NOT routinely give prophylactic anti-emetics such as metoclopramide (Maxolon) as risk of adverse reactions (dystonic reaction, restlessness, agitation, abdominal cramps from bloating) generally outweigh its prophylactic benefit.
- migraine headache is usually best Mx with iv chlorpromazine while opiates should be avoided
- avoid opiates and tramadol in back pain as there is evidence suggests they are of little benefit over non-steroidal anti-inflammatory drugs (NSAIDs) and do more harm, especially for chronic pain, instead consider a stat dose of corticosteroids such as 75mg prednisolone if acute disabling pain
- neuropathic pain is usually best managed by neural pain modulators rather than traditional analgesics
- patients with chronic pain should be Mx with consideration of chronic pain factors
- drug dependent patients with acute pain should be Mx as per acute pain Mx in drug dependent patients
options for Mx of severe pain in other patients in the ED setting
- severe acute pain in other patients should be addressed promptly usually with iv opiates +/- nerve block if appropriate
- local anaesthesia - including regional blocks
- intranasal fentanyl in children - ideally could be given at triage prior to Xray of suspected fractured limbs
- inhaled Penthrane - particularly for pre-hospital use but useful in ED eg. reduction dislocated patella
- inhaled nitrous oxide 50% or 70% for procedural pain eg. iv insertion in children and some fractures in children
- im/iv ketamine for procedural pain eg. fracture manipulation in children
- low dose ketamine 0.2-0.3mg/kg load over 10 minutes then infuse at same dose hourly is an excellent analgesic adjunct
- iv lignocaine
- consider trying lignocaine IV 1-1.5mg/kg IV slow infusion (over 5-20 min.) for renal colic in patients for whom opiates and NSAIDs are high risk - a study from Iran suggested it works faster and better than iv morphine 1)
- patient-controlled analgesia (PCA) - particularly for those going to wards with ongoing pain eg. fractured ribs
options for less severe pain
- if discharging patient home on codeine, ideally should assess its efficacy in that patient (genetic issues) by observing for 1 hour post-dose in ED, and if no benefit, consider using oxycodone instead.
- panadeine +/- non-steroidal anti-inflammatory drugs (NSAIDs) if no C/I such as dehydration, allergy, epigastric pain or PH PU
- eg. panadeine ii tabs qid plus either indomethacin 100mg PR bd or 25-50mg o tds
- non-steroidal anti-inflammatory drugs (NSAIDs) appear better for fracture pain than panadeine in children 2)
- avoid tramadol and tapentadol in the elderly in particular as they have adverse effects and may not be better than placebo, but may consider it in younger patients if above fail and wish to avoid opiates and opioids
- paracetamol
- non-drug strategies (see below)
other specific use options
- chlorpromazine (Largactil) iv with iv fluids for Mx of acute migraine
- GTN s/l, topical or iv for the adult patient with chest pain in the ED
palliative care pain Mx
- see also: end of life care
palliative care patients with chronic kidney disease
- paracetamol
- more powerful options include:
- hydromorphone 0.25-0.5mg s/c or 0.5-1.0mg orally prn
- fentanyl 12.5mcg s/c prn
- buprenorphine 100-200mcg s/lingual prn
- gabapentin or pregabalin may be useful for neuropathic pain
- methadone can be useful but complex pharmnacokinetics makes dosing challenging
- AVOID as metabolites renally excreted and toxicity may occur, or are nephrotoxic:
non-drug strategies to reduce pain
- elevate and splint injured limbs
- distraction techniques
- stress reduction
- physiotherapy
- cognitive behaviour therapy
- transcutaneous electric nerve stimulation (TENS)
- physical therapies:
- cold water immersions or alpha-lipoic acid may be tried in diabetic neuropathy
- ice massage - may help in herpetic neuralgia
Other references
analgesics.txt · Last modified: 2017/07/19 22:39 by 127.0.0.1