Morphine Flashcards
Morphine
Preparations 2
- Dilution: 10mg (1mL) diluted with 9mL NaCl to a total volume of 10mL. (1mg:1mL).
- Morphine/Midazolam Mix - 10mg (2mL) midazolam mixed with 10mg (1mL) morphine and diluted with 7mL sodium
chloride 0.9% to 10mL total volume. Morphine/Midazolam solution - 1mL = 1mg midazolam + 1mg morphine.
Morphine
Pharmacology
- Opioid analgesics act on receptors in the CNS and GIT producing analgesia, respiratory depression, sedation and
constipation. They act mainly at mu-opioid receptors in the CNS, reducing transmission of the pain impulse, and by
modulating the descending inhibitory pathways from the brain.
Morphine
Metabolism
- Morphine is metabolised principally in the liver by conjugation with glucuronic acid and 90% of the dose is recovered in urine within 24 hours. Approximately 7 to 10% of the dose is recovered in faeces, the majority after conjugation and
excretion via bile.
Morphine
Route Onset Duration Half-life
IM / SC
IV
Morphine
Route Onset Duration Half-life
IM / SC 5-10min 1-2hrs 1.5-2hrs
IV 2-5min 1-2hrs 1.5-2hrs
Morphine
Indications
1 CPG
3 Protocol Specific
CPG Specific Indication/s
* Analgesia.
Protocol CPG Specific Indication/s
* Dysrhythmias - Bradycardia (C7).
* Palliative care (Protocol S9).
* Return of spontaneous circulation (ROSC) (C16).
Morphine
Contraindications 4
⛔ Allergy or hypersensitivity to morphine.
⛔ Neonates <40 weeks (corrected) age.
⛔ Pregnant women ≥20 weeks gestation in labour.
⛔ Kidney disease (renal failure).
Morphine
Adverse/Side Effects
Common
Infrequent
Rare
- Common (>1%) - nausea and vomiting, dyspepsia, drowsiness, dizziness, headache, orthostatic hypotension, itch, dry
mouth, miosis, urinary retention, constipation. - Infrequent (0.1–1%) - dose-related respiratory depression, bronchospasm, confusion, hallucinations, delirium, agitation,
mood changes, tremor, visual disturbances, urticaria, hypothermia, bradycardia or tachycardia, hypertension, biliary
spasm, paralytic ileus, raised liver enzymes, muscle rigidity, myoclonus (with high doses), flushing due to histamine
release. - Rare (<0.1%) - SIADH, anaphylaxis, seizure.
Morphine
Precautions / Warnings 6
- Respiratory depression - Serious, life-threatening or fatal respiratory depression can occur with the use of opioids.
Patients should be monitored closely for respiratory depression at these times. - Shock patients - In patients with shock, impaired perfusion may prevent complete absorption following subcutaneous or intramuscular injection of morphine. Repeated administration may result in overdosage due to an excessive amount of
morphine suddenly being absorbed when circulation is restored. - Use in hepatic and renal impairment - Morphine may have a prolonged duration and cumulative effect in patients with
liver and kidney dysfunction. In these patients, analgesia may last for 6, 8 or even up to 24 hours following a standard
dose. Continuous infusions are contraindicated in these patients. - Use in pregnancy (Category C) - Morphine is not recommended for use in women during and immediately before
labour. The effects of opioid analgesics are unpredictable. They may prolong labour by temporarily reducing the strength,
duration and frequency of uterine contractions, or conversely they may tend to shorten labour by increasing the rate of
cervical dilatation. - Use in lactation - Morphine is excreted in human milk and breast-feeding is not recommended while a patient is receiving
morphine. - Effects on Ability to Drive and Use Machines – Morphine may cause drowsiness and general impairment of coordination
and may impair the mental and/or physical abilities required for the performance of potentially hazardous
tasks, such as driving a car or operating machinery. Ambulatory patients should be cautioned against driving or operating
machinery.
Morphine
Interactions
- Morphine should be used with caution and with reduced dosage considered when used concurrently with patients
receiving other central nervous system depressants (including alcohol), due to the risk of profound sedation, respiratory
depression and hypotension.
Morphine
Notes
- Elderly patients and those with limited physiological reserves:
- Opioid dose requirement decreases progressively with age.
- There is an increased risk of adverse effects in patients who are elderly and/or have limited physiological reserves
including cognitive impairment, sedation, respiratory depression and falls.
Morphine
Analgesia
Dose
Adult
Note * In the elderly and/or frail and/or critically ill (e.g. shocked) patient use 50% of the recommended lower end of the adult
dose range.
IV/IO Diluted
Initial Dose: 2.5-5mg diluted
Repeat: 5 minutes
Maximum Total Dose: 0.5mg/kg
IM/Subcut
Initial Dose: 5-10mg
Repeat: 15 minutes
Maximum Total Dose: 2 doses
Morphine
Analgesia
Dose
Paediatric ≥ 1 years of age
IV/IO Diluted
Initial Dose: 100microg/kg diluted (max bolus 5mg)
Repeat: 5 minutes
Maximum Total Dose: 0.5mg/kg
IM/Subcut
Initial Dose: 100microg/kg (max bolus 10mg)
Repeat: 15 minutes
Maximum Total Dose: 2 doses
Morphine
Analgesia
Dose
Paediatric < 1 year of age
IM/Subcut Diluted
Initial Dose: 100microg/kg diluted (max bolus 10mg)
Repeat: 30 minutes
Maximum Total Dose: 2 doses
Morphine
Bradycardia - Distress/pain post initiation of TCP
Dose
ADULT ONLY
+Note
IV Diluted
Initial Dose: 2.5mg Diluted
Repeat: 2-5 minutes
Maximum Total Dose: 15mg
NOTE: The IV regimen may be repeated 20 mins post last administration.
Morphine
Palliative Care - Pain/breathlessness in the last days of life
Dose
ADULT ONLY
+Note
Subcut
Initial Dose: 2.5-5mg
Repeat: up to 15 minutes
Maximum Total Dose: 10mg (Per episode), 15mg (24 hours)
NOTE: Regimen may be repeated 4 hours after the last administration.
Morphine
ROSC - Post ROSC sedation
Dose
Adult
+ Note
IV/IO
Initial Dose: 2.5mL morphine/midazolam mix bolus
Repeat: 3 minutes
Maximum Total Dose: 15mL
IM
Initial Dose: 5mL morphine/midazolam mix bolus
Repeat: 15 minutes
Maximum Total Dose: 15mL
Notes – IV Regimen for Post Intubation/SGA Sedation may be repeated 20 minutes after the last administration.
Morphine
ROSC - Post ROSC sedation
Dose
Paediatric (≥ 6 months of age)
+ Note
IV/IO
Initial Dose: 0.1mL/kg morphine/midazolam mix bolus (max bolus 2.5mL)
Repeat: 3 minutes
Maximum Total Dose: 0.3mL/kg
IM
Initial Dose: 0.1mL/kg morphine/midazolam mix bolus (max bolus 2.5mL)
Repeat: 15 minutes
Maximum Total Dose: 0.3mL/kg
Notes – IV Regimen for Post Intubation/SGA Sedation may be repeated 20 minutes after the last administration.
