Complications of Conscious Sedation

Question 1

What is used in inhalation sedation?

Answer 1

Nitrous oxide

Question 2

What is used in IV sedation?

Answer 2

Midazolam

Question 3

What is the reversal drug for midazolam?

Answer 3

Flumazenil

Question 4

What are the most common complications of IV sedation?

Answer 4

Venospasm
Extravascular injection
Intraarterial injection
Haematoma
Fainting

Question 5

What is venospasm?

Answer 5

Disappearing vein syndrome
Veins collapse at attempted venepuncture
May be accompanied by burning
Associated with poorly visible veins

Question 6

What is the management of venospasm?

Answer 6

Time dilating vein
-worse with repeated attempts
Efficient technique
-slow skin puncture makes worse
Warm water/gloves in winter

Question 7

What is extravascular injection?
Diagnosis?

Answer 7

Active drug placed into interstitial space
Drug sits in the hand and does not disperse properly, delayed absorption
Diagnosis- pain & swelling

Question 8

What is the management of extravascular injection?

Answer 8

Prevention
–good cannulation
–test dose of saline- flush
Treatment
–remove cannula, apply pressure & reassure

Question 9

What is the diagnosis of intra-arterial injection?

Answer 9

Pain on venepuncture
Red blood in cannula
Difficult to prevent leaks
Pain radiating from site of cannulation
Loss of colour or warmth to limb/weakening pulse

Question 10

What is the management of intra-arterial injections?

Answer 10

Monitor for loss of pulse
–cold and discoloured
Leave cannula in situ for 5 minutes post drug
No problems- remove
Symptomatic leave & refer to hospital

Question 11

What is a haematoma?

Answer 11

Extravasation of blood into soft tissues
Due to damage to vein walls

Question 12

How can you prevent a haematoma from occurring?

Answer 12

Good cannulation technique
Pressure post operatively
Care with the elderly

Question 13

What is the treatment of a haematoma?

Answer 13

Time
Rest
Reassurance
If severe
–ice pack
–moist heat 20 mins in hour after 24hrs
Consider heparin containing gel

Question 14

What is the threshold of mg of midazolam to abandon sedation?
Dental care setting?
Hospital setting?

Answer 14

Dental care setting- 10mg
Hospital setting- 15mg

Question 15

What are some complications of drug administration with IV sedation?

Answer 15

Hyper-responders
Hypo-responders
Parodoxical reactions
Oversedation
Allergic reactions

Question 16

What is a parodoxical reaction to drug adminstration?

Answer 16

Appear to sedate normally
React extremely to all stimuli
Relax when stimuli is removed
Check for failure of LA
Do not continue adding sedative

Question 17

What does oversedation cause?

Answer 17

Loss of responsiveness
Respiratory depression
Loss of ability to maintain airway
Respiratory arrest

Question 18

What is the management of oversedation?

Answer 18

Stop procedure
Try to rouse patient
ABC
If no response to stimulation and support
–reverse with flumazenil
–watch for 1-4 hours

Question 19

What is the management of respiratory depression?

Answer 19

Check the oximeter
Stimulate patient (encourage to breath)
Supplemental oxygen
–nasal cannulae 2 litres per minute
–if no improvement, stop treatment and 15 litres per minute non rebreathing mask
Reverse with flumazenil if no improvement

Question 20

What are the common complications of inhalation sedation?

Answer 20

Oversedation
Patient panics

Question 21

What are the signs and symptoms of nitrous oxide overdose?

Answer 21

Patient discomfort
Lack of co-operation
Mouth breathing
Giggling
Nausea
Vomiting
Loss of consciousness

Question 22

What is the treatment for nitrous oxide overdose?

Answer 22

Decrease nitrous oxide concentration by 5-10%
Reassure
Don’t remove nosepiece (diffusion hypoxia)