Pain Flashcards
Describe how pain can be assessed.
Subjectively - ask pt to grade pain, mild, moderate,severe
Objectively - clinical features of pain - tachycardia, tachypnoea, hen, sweating, flushing - unwillingness to mobilise or agitation in those less able to communicate pain.
Assess when mobile, when taking a deep breath and when in bed
What are the consequences of poor post-op pain control?
Slower recovery
Its are reluctant to mobilise, in turn resulting in slower restoration of function and rehabilitation
Pt in pain following abdominal surgery will not breathe as deeply - inadequate ventilation - subsequent atelectasis and HAP
Describe the WHO analgesic ladder
- simple analgesics (paracetamol/NSAIDs)
- IF pain is not well controlled, move up to the next stage of the ladder and consider weak opiates such as codeine or tramadol + non-opioid + adjuvant
Assess again after couple of hours. - If this is still inadequate move to next step and prescribe morphine or other stronger opiates + non-opioid + adjuvant
Consider alternative to the oral route such as topical, IV, subset
If this fails and sinister causes of pain have been ruled out, consider specialist help and/or a patient-controlled analgesia pump
As patients recover, move down the ladder and wean down analgesia to a simple regimen.
Describe simple analgesics.
Paracetamol and/or NSAIDs (e.g. ibuprofen, naproxen, diclofenac)
How do NSAIDs work? What are they commonly used for? Side effects?
NSAIDs work by inhibiting prostaglandin synthesis, reducing the potential inflammatory response causing the pain.
Anti-inflammatory properties mean such analgesics are often used in MSK conditions and intra-operatively
Side effects of NSAIDS (I GRAB)
Interactions with other meds (e.g. warfarin)
Gastric ulceration (consider coprescribing PPI)
Renal impairment (contraindicated in CKD/AKI)
Asthma sensitivity
Bleeding risk (due to effect on platelet function)
What are weak opiates and strong opiates? How do they work?
Weak - codeine, tramadol
Strong - morphine, oxycodone, fentanyl
Activate opioid receptors
What are side effects of opioids? What should therefore be prescribed alongside? Give some examples
Constipation, nausea
Laxatives - senna, lactulose, fybogel
Anti-emetics - cyclizine, metoclopramide
Sedation and confusion, respiratory depression, pruritus, tolerance and dependance (rare)
What should you prescribe with opiates?
Laxative
Anti-emetic
Paracetamol to reduce requirement
Why should you avoid strong and weak opiates together?
Competitively inhibit the same receptor
What should be used if opioid analgesia is required in pt with renal impairment?
Oxycodone or fentanyl
Rather than morphine
What should you be aware of if the PO route is contraindicated?
IV morphine has 80% bioavailability compared to 30% oral
Takes 2-3 minutes to work compared to 20 minute oral and 15 minutes IM
Post-op, many patients require more intense or immediate analgesia. What can be used in this case?
Patient controlled analgesia - use of IV pumps that provide a bolus dose of analgesic when pt presses a button.
What are the advantages and disadvantages of Patient controlled analgesia?
+
Provides analgesia tailored to patients requirements
Safe - risk of overdose is negligible
Can accurately record how much opioid is being administered
-
Can be cumbersome and prevent the patient mobilising
Not appropriate for those with poor manual dexterity or learning difficulties
Whatcauses neuropathic pain? What does it feel like?
Irritation or injury directly to the nerves, either peripherally or centrally
Presents with shooting or stabbing pains, can be described as an electric shock
How is neuropathic pain managed?
Non-pharmacological - CBT, transcutatenous electrical stimulation, capsaicin cream
Pharmacological:
Amitriptyline
Pregabalin
Gabapentin - imitates inhibitory GABA - inhibiting Ca channels
