complications of conscious sedation

Question 1

what is flumazenil

Answer 1

• reversal drug for sedation

Question 2

what are complications if cannulation

Answer 2

• venospasm
• extravascular injection
• intraarterial injection
• haematoma
• fainting

Question 3

what is venospasm

Answer 3

• disappearing vein syndrome, vein collapses as you go in with cannula
• can be accompanied by burning feeling
• associate with poorly visible veins

Question 4

management fo venospams

Answer 4

• worse with repeated attempts
• go fast, slow makes it worse
  -weaer gloves before, or use hot water to dilate

Question 5

what is extravascular injection

Answer 5

• drug placed in interstitial space
• pain, swelling
• delayed absorption. problem = could pversedate pt

Question 6

management of extravascular injection

Answer 6

• good techniques, test with saline
• remove cannula, apply pressure, reassure

Question 7

what is intraarterial injection

Answer 7

• pain on venipuncture as artery walls thicker
• red blod in cannula
• difficult to prevent leaks
• pain radiating distally from cannulation site
• loss of colour or warmth to limb, weakening pulse

Question 8

management of intra-arterial injection

Answer 8

• palpate first to check no pulse
• monitor for pulse loss
• leave cannula in for 5 mins
• if no problems then remove
• if symptomatic, leave nd refer to hospital

Question 9

what is haematoma

Answer 9

• extravasation of blood into soft tissues = big bruise
• due to damage to vein walls from poor technique or when removing cannula failed to apply pressure
• care with elderly pts

Question 10

Management of haematoma

Answer 10

• good technique, pressure post-op
• initial ice pack, moist heat 20 mins in, consider hearing containing gel if severe

Question 11

how to prevent fainting from cannulation

Answer 11

• anxiety related usually, try get pt to relax
• make sure pt has eaten
• can give IS to relax them enough
• topical skin analgesia can help

Question 12

what are the complications of drug administration

Answer 12

• hyper-responders
• hypo-responders
• paradoxical reactions
• oversedation
• allergic reactions
• sexual fantasy

Question 13

what are hyper-responders

Answer 13

• deep sedation with minimal dose
• care with titration needed = only 1mg increments after initial 5mg dose
• more common in elderly

Question 14

what are hypo-responders

Answer 14

• little effect with large dose
• check cannula is in the vein
• some pts lie about feeling it
• can be due to a drug tolerance pt never told you about

Question 15

what is the highest threshold for drug

Answer 15

• shouldn’t go over 10mg, BNF actually says 7.5mg

Question 16

what are paradoxical reactions

Answer 16

• appear to sedate normally
• react extremely to all stimuli, then relax when stimuli removed
• check failure of LA
• don’t add more sedation, find another management technique
• more likely in younger pts

Question 17

how to know if oversedated

Answer 17

• loss of consciousness, lose verbal contact, respirator depression, loss of ability to maintain airway (respiratory arrest)

Question 18

what is the management of over-sedarion

Answer 18

• stop procedure and try rouse pt
• if not waking, start ABC
• if no response t stimulation and support, reverse with flumazenil 200µg then 100µg increments at minute intervals
• watch for 4 hours as flumazenil has a shorter half life than midazolam so pt can go back into sedation again

Question 19

management of respiratory depression

Answer 19

• check oximeter
• need mechanical and clinical monitoring, don’t want it to drop below 90%
• ask pt to take deep breathe sometimes that’s enough
• give supplemental O2 through nasal cannulae at 2 litres per minute
• if not getting better, reverse

Question 20

management of loss of airway control and/or respiratory arrest

Answer 20

• stimulate pt/assess consciousness
• maintain/clear airway
• ventilate pt
• reverse sedation

Question 21

what to do if allergic reaction

Answer 21

• manage as if pt not sedated
• give IM adrenaline if need be

Question 22

what not to do if allergic reaction

Answer 22

• don’t give flumazenil as it is also a benzodiazepine like midazolam so would not help

Question 23

what is the maximum dose of nitrous oxide that can be given during sedation

Answer 23

• 70%

Question 24

signs of nitrous oxide over-sedation

Answer 24

• pt discomfort
• lack of cooperatoin
• mouth breathing
• lots of giggling
• nausea
• vomiting
• LoC

Question 25

what is a likely cause of over sedatoin

Answer 25

- can misjudge dose - or may have needed to give more sedative to get the to sedate as so nervous, but now not as scared and so don't need as much but you give same level so over sedate them

Question 26

treatment of oversedation

Answer 26

- decrease nitrous oxide conc. by 5-10% - reassure - don't remove nosepiece as can get diffusion hypoxia

Question 27

what is diffusion hypoxia

Answer 27

- massive diffusion gradient as nitrous oxide in the body is much higher than outside, so the body wants to get rid of it quickly and rush ou, but that would stop any oxygen from getting into the body so need to gradually bring pt back to 100% O2 and stay there for 3-5 minutes to prevent that happening

Question 28

what is common with over sedation

Answer 28

- vomiting