Sedation - IV Complications Flashcards
What are the types of complications that can occur during cannulation? (5)
- Venospasm
- Extravascular injection
- Intraarterial injection
- Haematoma
- Fainting
what is venospasm?
(Disappearing vein syndrome)
- Veins collapse at attempted venepuncture
- May be accompanied by burning/pain
- Associated with poorly visible veins
How do we prevent vasospasm? (3)
- Ensure vein dilated (i.e. with tourniquet and tapping) = Worse with repeated attempts
- Efficient technique = Slow skin puncture makes worse
- Use warm water / gloves in winter to ensure good veins for puncture
What is an extravascular injection?
A complication where the active drug placed into interstitial space as canula isn’t placed in the vein.
How do we Diagnose an extravascular injection? (2)
- Pain
- Swelling
How do we avoid extravascular injections?
Flush the canula with saline before providing the active drug and if no pain/swelling = correct placement.
Bubble appears = incorrect placement and must replace
What are the potential problem associated with an extravascular injection? (1)
Delayed absorption (30 mins for midazolam) through the tissues so can be a potential for overdose if more drug given with the correct placement of the canula.
How do we manage an extravascular injection? (2)
• Prevention
- Good cannulation
- Test dose of saline
• Treatment:
- Remove cannula
- Apply pressure
- Reassure
- Replace
How do we diagnose an Intra-arterial injection? (6)
- Pain on venepuncture since artery wall thicker
- Bright red blood in cannula
- Canula will buckle from pressure within artery
- Difficult to prevent leaks
- Pain radiating distally from site of cannulation
- Loss of colour or warmth to limb / weakening pulse
What puncture location does an intra-arterial injection commonly occur?
antecubital fossa
How do we prevent an intra-arterial injection? (3)
- Avoid anatomically prone sites – avoid ACF which is medial to biceps tendon
- Palpate before puncture: if there is a pule = NOT a vein
How do we manage an intra-arterial injection when no drug has been administered? (2)
- Remove and apply pressure for prolonged period of time
- When you remove the canula monitor for loss of pulse or colour
= Cold: caused when artery gets irritated and constricts
= Discolouration
How do we manage an intra-arterial injection when drugs have been administered? (3)
Leave cannula in situ for 5 mins post drug;
- No problems with colour or temp = remove
- Symptomatic = refer to A&E (procaine 1%) as artery can get irritated and constrict
What is a haematoma?
Extravasation of blood into soft tissues due to damage to vein walls
- Common and expected
What is the cause of haematoma during puncture?
poor technique
What is the cause of haematoma during cannula removal?
Failure to apply pressure quickly and for long enough
How do we prevent haematomas? (3)
• Good cannulation technique
- Avoid multiple holes in vein wall (scratching the vein walls)
• Pressure post operatively – quickly and for long enough (Operator and patient)
• Care with the elderly
How do we treat haematomas? (6)
• Time
• Rest
• Reassurance
(Usually not needed)
however, If severe:
- Initial ice pack
- Moist heat pack for 20mins an hour after
- After 24hours consider heparin containing gel
What causes fainting during venepuncture? (2)
- Anxiety related to venepuncture (needle)
- px not eaten (worsened)
How do we prevent fainting during venepuncture? (6)
- Good technique
- Ask if px prone to fainting
- Don’t starve patients
- Topical skin anaesthesia
- Inhalation sedation First: to relax before canulation
- Position of patient: have patients slightly reclined so that there is room to have them reclined all the way back if the faint
What are the types of complications that can occur during drug administration? (5)
- Hyper-responders
- Hypo-responders
- Parodoxical reactions
- Oversedation
- Allergic reactions
What is a hyper-response to IV sedation?
Where a patient is deeply sedated with minimal dose of 1-2mg midazolam (very quick)
What causes a hyper-response to IV sedation?
Usually age – over 60’s have a different titration path to avoid this
How do we prevent a hyper-response? (2)
Care with titration;
- 1mg increments
- Slow titration in elderly: 0.5mg initially to gage response then small increments after this
What is a hypo-response to IV sedation?
Where a patient has little sedative effect with large doses of drug (midazolam)
How do we manage a hypo-responder? (3)
• Check cannula in vein – flush to confirm
• Take time - Could be a slow effect – caution
• May be due to tolerance - explore history further
- BZD induced: check if px has a history of taking benzodiazepines = high tolerance
- Cross tolerance (if px have other drug habits)
- Idiopathic (unsure)
If a patient is a hypo-responder what is the threshold to abandon?
don’t go over 10mg if not having an effect
What is a paradoxical reaction?
Px doesn’t sedate how you would expect
How do we manage a paradoxical reaction? (4)
- Check for failure of LA
- DO NOT GO ON ADDING SEDATIVE
- use other management techniques
In what px group do we have to be cautious with paradoxical reactions?
immature teenagers (most common between 12-16 years old)
How do we identify oversedation? (4)
- Loss of responsiveness: no verbal contact
- Respiratory depression: can be manageable (give oxygen and ask patient to take deep breathes if responsive) or unmanageable
- If drug continues to be given = Loss of ability to maintain airway
- Respiratory arrest
How do we manage oversedation? (4)
• Stop procedure
• Try to rouse patient
• Carry out ACVPU and if patient unresponsive carry out A B C = airways, breathing, circulation.
• If no response to stimulation and support;
- Reverse with flumazenil
- Watch for 1- 4 hours
If managed = patient able to breathe by themselves again
What dose of flumazenil is used to reverse over sedation?
200mg initial dose
then 100mg increments at minute intervals after to reverse
How do we manage respiratory depression? (3)
- Stimulate patient: Ask to take a deep breathe if saturation is below 90%
- Supplemental oxygen = Nasal cannulae with 3 litres per minute
- If saturation drps below 90% and doesn’t rise = Reverse with flumazenil
How do we manage allergy during IV sedation? (2)
Do not reverse the drug as the reversal drug is also a benzodiazepine (further allergy)
Same as any other allergy emergency - IM adrenaline
- keep IV access (can be useful for other medical professionals)
