Post-Operative Pain Management Flashcards
What can pain be divided into?
Acute and chronic types
In what respects can post-operative pain be assessed?
Subjectively and objectively
How is post-operative pain assessed subjectively?
By asking the patient to grade their pain on a scale of mild, moderate, or severe
What can subjective post-operative pain be assessed as part of?
Regular nursing observations
Why is asking the patient to grade their pain on a scale from 1 to 10 problematic?
Because it requires the patient to quantify their pain into a number, and then the doctor is then required to interpret that into an appropriate analgesia regime
How is pain assessed objectively?
By looking at the clinical features of pain
What are the clinical features of pain?
- Tachycardia
- Tachypnoea
- Hypertension
- Sweating
- Flushing
- Unwillingness to mobilise or agitation in those that are less able to communicate their pain
In what situations should each patient be assessed for pain?
- When mobile
- When taking a deep breath
- When in bed
What does inadequate control of post-operative pain result in?
Slower recovery
Give 2 examples of how poor post-operative pain control can lead to slower recovery?
- Patients with poorly controlled pain are often reluctant to mobilise, in turn resulting in slower restoration of function and rehabilitation capacity
- Patients in pain following abdominal surgery will not breath as deeply as they normally wound, resulting in adequate ventilation and subsequent atelectasis and hospital acquired pneumonia
What is the best known method for approaching pain relief?
The WHO analgesic ladder
What does the WHO analgesic ladder provide?
A strategy for titrating analgesia
What is started with on the WHO analgesic ladder?
Simple analgesics such as paracetamol or NSAIDs
What should be done if simple analgesics are not controlling pain well enough?
Should move up to the next stage of the ladder, and consider prescribing weak opiates, such as codeine or tramadol
What should be done if weak opiates are not controlled pain adequately?
Move up to the next step, and prescribe morphine or other stronger opiates
What can be done if stronger opiates are not sufficient?
Consider alternatives to the oral route, such as topical, intravenous, or subcutaneous
What can be done if parenteral strong opiates fails, and sinister causes of pain have been ruled out?
Consider specialist help and/or a patient-controlled analgesia pump
What might neuropathic pain respond better to?
Alternative analgesics such as amitriptyline or gabapentin
What should be done as patients recover, regarding pain management?
It is important to move down the ladder, and wean down the analgesia to a simple regime
What does non-opioid analgesia consist of?
Paracetamol and/or NSAIDs
Give two examples of NSAIDs
- Diclofenac
- Ibuprofen
How do NSAIDs work?
By inhibiting the synthesis of prostaglandins, thereby reducing the potential inflammatory response causing the pain
What are the adverse effects of NSAIDs?
- Interactions with other medications, e.g. warfarin
- Gastric ulceration
- Renal impairment
- Can trigger asthma
- Bleeding risk
What are opiates divded into?
- Weak opiates
- Strong opiates
Give three examples of strong opiates
- Morphine
- Oxycodine
- Fentanyl
How do opiates work?
By activating the opiod receptors (MOP, DOP, and KOP), which are distibuted throughout the central nervous system
What side effect will most patients on opiates experience?
Constipation and nausea
How are the side effects of constipation and nausea with opiates dealt with?
Concurrent prescription of laxatives and anti-emetics
What are the other side effects of opiates?
- Sedation
- Confusion
- Respiratory depression
- Pruritis
- Tolerance and dependance
What should be prescribed if regular opiates are needed?
Concurrent regular paracetamol
Why should concurrent regular paracetamol be prescribed alongside regular opiates?
To reduce their requirements
Can weak and strong opiates be used in combination?
This should be avoided
Why should you avoid weak and strong opiates in combination?
As they competitively inhibit the same receptor to varying degrees
What should be done if PRN opiates are frequently called for?
You should assess the 24-hour opiate requirement, and consider titration into a regular basal dose of modified release preparations
What drug should be used if opioid analgesia is required in a patient with renal impairment?
Consider oxycodone or fentanyl rather than morphine
What should be done if the oral route is contraindicated when providing analgesia?
Consider topical patches and use IV morphine for breakthrough analgesia
How does the bioavailability compare between different routes of administration of morphine?
The bioavailability of oral morphine is 30%, whereas it is 80% for IV or SC morphine
How long does morphine take to work if given intravenously?
20 minutes
How long does morphine take to work if given orally?
20 minutes
How long does morphine take to work if given intramuscularly?
15 minutes
When might patient controlled analgesia be required post-operatively?
Post-operatively, many patients require more intense or immediate analgesia, and their requirements exceed the capacity of what the nursing staff can provide
What does patient controlled analgesia involve?
The use of IV pumps that provide a bolus dose of an analgesic when the patient presses a button
Where are patient controlled analgesia pumps started?
Usually in theatre or on the wards
What is the decision to start a patient controlled analgesia pump in theatre based on?
Clinical experience of analgesia requirements of the specific operation by the surgical staff
What are the advantages of patient controlled analgesia?
- Provides analgesia that is tailored to the patients requirements
- Safe - the risk of overdose is negligible
- Can accurately record how much opoid is being administered, which can be converted to a regular dose
What are the disadvantages of patient controlled analgesia?
- Can be cumbersome and prevent the patient from mobilising
- Not appropriate for those with poor manual dexterity or learning difficulties
What does neuropathic pain result from?
Irritation or injury directly to the nerves, either peripherally or centrally
How does neuropathic pain present?
Shooting or stabbing pains, can be described as like an electrical shock
What is the prevalence of neuropathic pain following surgery?
As high as 10%
After what surgeries is neuropathic pain frequently encounted?
After orthopedic or vascular surgery, particularly in amputees
Why is neuropathic pain common in amputees?
Due to the nerve damage sustained when the limb is severed
What can the management of neuropathic pain be split into?
Pharmacological and non-pharmacological methods
What offers the best results in the management of neuropathic pain?
A combination of approaches
What non-pharmacological treatment can be used in neuropathic pain?
- Cognitive behavioural therapy
- Transcutaneous electric nerve stimulation
- Capsaicin cream
What are the pharmacological therapies used in neuropathic pain?
- Gabapentin
- Amitriptyline
- Pregabalin
