Sedation / analgesia Flashcards
3 core features of delirium
- A disturbance of consciousness (i.e. reduced awareness of the environment, with reduced
ability to focus, sustain or shift attention) - A change in cognition (i.e. impaired problem solving or memory) or a perceptual
disturbance - Onset within hours or days, with a tendency to fluctuate
Name 3 critical illness factors that may contribute to delirium
Acidosis.
• Hypoxaemia: anaemia, pulmonary or cardiac failure.
• Sepsis/Fever.
• Hypotension.
• Metabolic and electrolyte disturbances.
• Hepatic and renal failure.
• Poisons: carbon monoxide, metabolic blockade, pesticides, solvents, mercury, lead.
• CNS pathology: abscesses, haemorrhage, hydrocephalus, subdural haematoma, infections,
seizures, stroke, tumours, metastases, vasculitis, encephalitis, meningitis.
Name an assessment tool for delirium in ICU
- The Confusion Assessment Method in the ICU (CAM-ICU).
2. The Intensive Care Delirium Screening Checklist
How to assess CAM-ICU ? When is it positive
- Acute onset or fluctuating course.
- Inattention.
- Altered level of consciousness.
- Disorganised thinking.
The patient is considered to be CAM-ICU Positive or DELIRIOUS when Features 1 AND 2 and
EITHER Feature 3 OR 4 are present.
Non-pharmacological management of Delerium - name 3
Orientation
• Provide visual and hearing aids.
• Encourage communication and re-orientate the patient repetitively.
• Have the same nurse caring for the patient where possible.
• Display familiar objects from patient’s home, in the room.
• Allow television during the day, with daily news.
• Non-verbal music.
Environment
• Sleep aids: lights on during the day, off at night.
• Control excess noise at night.
• Ambulate and mobilise patient early and often.
Clinical parameters.
• Maintain systolic pressure > 90 mmHg.
• Maintain oxygen saturations > 92%.
• Treat underlying metabolic derangements and infections.
Sedation/analgesia in delerium - how can you reduce delerium
• Assess the need for all current medications, especially sedatives, analgesics and
anticholinergic drugs.
- Daily sedations breaks to titrate appropriate sedative/analgesic requirements.
- Adequate analgesia will reduce the risk of delirium if the pain is a problem.
Approved med for acute hyperactive delirium in critical care
haloperidol
quetiapine also used
Name 3 complications of inadequate sedation/analgesia
Stress response -> reduced immunity, increased catabolism, hypercoagulopathy
sleep deprivation -> prolonged recovery
worsened pulm function
inadvertent removal of lines/tubes
anxiety - and PTSD
FAILURE TO COMPLY WITH TREATMENT
Name 3 complications of excessive sedation/analgesia
difficult to assess neuro function
increased duration of mechanical ventilation
Increased cardiovascular depression and increased vasoactive agent use
agitated / disorientated patient
increased length of stay
delusional memories an -> PTSD
2 ways of assessing pain
patient reported
pain observation tools Eg - Critical Care Pain Observation tool CPOT
Tool for assess sedation/agitation
Richmond agitation sedation scale RASS
Sdation-agitation scale - SAS
Propofol usual dose in adults for sedation
Propofol is available in a 1% and 2% preparation
sedation in adults is run between 1 and 20ml/hr of 1% with titration to a pre-defined end point.
Name 3 side effects propofol
Respiratory depression and suppression of laryngeal reflexes, requiring caution with its use in patients with unsecured airways.
Cardiovascular depression with a negative inotropic and chronotropic effect and a reduction in systemic vascular resistance.
=hypotension + bradycardia
Great care must therefore be taken with hypovolaemic or cardiovascularly unstable patients, and inotropes/vasopressors should be to hand if propofol boluses are being administered.
Pain when administered peripherally.
Hypertriglycerideaemia and Propofol Infusion Syndrome
Bar sedation name another use of propofol
refractory status epilepticus
as part of a treatment regimen for raised intracranial pressure, e.g. in traumatic brain injuries.
What is propofol infusion syndrome?
acute bradycardia resistant to treatment and progressing to asystole associated with prolonged (>48hrs) high dose (>5mg/kg/hr) propofol infusion
Who is susceptible to propofol infusion syndrome?
How to avoid?
avoid using prolonged high dose infusions of propofol, but rather use alternative agents alone or in combination
Dont use propofol alone in children for long term
Uses of benzos - name 3
sedation, hypnosis, anxyiolysis, anterograde amnesia, muscle relaxation anti-epileptic.
Benzo mechanism
GABA-mediated inhibition
Main 2 complications of benzos
hypotension in haemodynamically unstable patients
hypoventilation
Paradoxical agitation
Usual dose midazolam
1mg/ml solution and run between 1 and 10mls/hr
with titration to a pre-determined end point
Midazolam onset offset time ? accumulation ?
rapid onset (0.5-2.5 mins) and a reasonably rapid offset (30 to 60 mins) It, therefore, tends to be given by infusion.
Minimal accumulation occurs with short infusions (< 24hours) but is seen thereafter.
Diazepam onset off set time ?
very long terminal elimination half-life and active metabolites.
Intravenously diazepam has a reasonably rapid onset of action (within 2-3 mins) with repeat
doses every 2-4 hours.
Enterally diazepam takes approximately 30-60 minutes for onset of action
only really administered intermittently to minimise accumulation.
Usual dose diazepam
0.5-5mg intravenously
2-10mg enterally
Lorazepam duration
long duration of action (6-10hours)
making it less titratable
Lorazepam benefit vs midazolam ? why?
wake-up has been found to be more predictable than midazolam’s with prolonged infusion.
lorazepam’s metabolism is less influenced by other factors (e.g. drugs),
its metabolites are inactive and it has a more stable context-sensitive half time
