Complications Of Conscious Sedation

Question 1

What is conscious sedation?

Answer 1

Use of a drug or drugs to depress the CNS, enabling treatment to be carried out, during which verbal contact is maintained with the patient.

Drugs used should have a margin of safety to ensure pt remains conscious

Question 2

What complications may arise from IV sedation?

Answer 2

Difficulty placing canula

Venospasm

Extravascular injection

Intra arterial injection

Haematoma

Fainting

Question 3

What is venospasm?

Answer 3

Disappearing vein

Veins collapse at attempted venupuncture

May be accompanied by burning

Associated with poorly visible veins

Question 4

How might venospasm be managed?

Answer 4

Spend time dilating the vein

Use efficient technique with fast skin puncture

Warm water before / gloves in winter for pt

Question 5

What is extravascular injection? What may present?

Answer 5

Drug injected into tissue

• pain
• swelling

Potential problems
- delayed absorption

Question 6

Best management for extravascular injection?

Answer 6

Prevention! - good canulation

Test dose of saline first

Remove canula, apply pressure and reassure

Question 7

What may present with intra-arterial injection

Answer 7

Pain on venupuncture

Red blood in the canula

Difficulty to prevent leaks

Pain radiates distally from site

Loss of colour or warmth to the limb

Question 8

Management of intra-arterial injection?

Answer 8

Monitor for loss of pulse

Leave cannula in situ for 5 mins post drug delivery

No problems - remove

Symptomatic, leave and refer to hospital - procaine1% topical

Question 9

Why may haematoma occur?

Answer 9

Poor venupuncture technique

Failure to apply pressure when removing cannula

Take care with the elderly

Question 10

Treatment of haematoma?

Answer 10

Initial ice pack for 20 mins if bad

Time, rest, reassurance

Consider heparin containing gel

Question 11

How prevent pt fainting during venupuncture?

Answer 11

Not allow patient to be starved

Topical skin anaesthesia

Attempt to remove anxiety

Question 12

What types of complication may occur with IV sedation?

Answer 12

Hyper-responders

Hypo-responders

Paradoxical reactions

Oversedation

Allergic reactions

Question 13

What is a hyperesponder?

Answer 13

Deep sedation with minimal dose 1-2mg midazolam

Slow titration

Question 14

What is a hypo responder? What should you check?

Answer 14

Little sedative with large dose

Check cannula is in the vein!

May be idiopathic, may be due to existing tolerance to benzodiazepines

Threshold to abandon around 10mg in primary care

Question 15

What is a paradoxical reaction? What considerations should be made

Answer 15

Appear to sedate normally however react extremely to all stimuli

Check for failure of LA

Do not go on adding the sedative!!

Mind other management technique

Watch immature teenagers who may try to get more sedative!!!

Question 16

What may occur with oversedation?

Answer 16

Loss of responsiveness

Respiratory depression

Loss of ability to maintain airway

Respiratory arrest

Question 17

How manage oversedation?

Answer 17

Stop procedure

Try to rouse patient

ABC

If no response to stimulation and support, reverse with flumazenil 200mg then 100mg increments at minute intervals

Watch for 1-4 hours

Question 18

How manage respiratory depression?

Answer 18

Check oximeter

Stimulate patient and ask them to breathe

Provide supplemental oxygen as 2L per minute

Reverse with flumazenil

Question 19

What if allergic reaction?

Answer 19

Do not reverse as reversal drug is also benzodiazepine

Remember latex or Elastoplast may cause allergy

manage with adrenaline

Question 20

What complications may arise from IS?

Answer 20

Oversedation and patient panics

Question 21

Give some signs of N2O overdose?

Answer 21

Patient discomfort

Lack of co-operation

Mouth breathing

Giggling

Nausea or vomiting

Loss of consciousness

Question 22

How manage N2O overdose?

Answer 22

Decrease conc by 5-10%

Reassure

Don’t remove nosepiece as risk of diffusion hypoxia