Download Sedation and Analgesia in the PCCU: General Principles

Sedation and Analgesia in the PCCU
General Principles
Assessment
Thoughtful setting of sedation targets and careful assessment of the patient is more
important than what particular medications or dosing strategies are used.
Non-pharmacological factors
Environmental factors, relaxation, sleep patterns and day/night orientation,
communication, re-orientation, scheduled care, lightening and noise reduction must be
considered for all patients BEFORE medications are considered and should be
continued even when medication are used. Noxious stimuli such as a blocked urinary
catheter or underventilation must also be considered and eliminated or reduced where
possible.
Acute episodes of agitation or pain.
Treat with boluses, do not increase infusion. Boluses for acute episodes of agitation can
be given more frequently than q1h and should be repeated until effective. Don’t forget to
use non-pharmacological measures and assess for potentially noxious stimuli.
Short term intubations
If the anticipated duration of ventilation is short, intermittent prn doses are preferred.
When to move to the next step of the algorithm?
Consider moving to the next step of the algorithm when sedation scores are consistently
not in target range. Add or increase infusions only after the target is met with boluses.
Tolerance
With prolonged exposure to benzodiazepines and opiates patients often develop
tolerance, requiring gradually increasing doses to maintain the same level of sedation or
analgesia. Don’t forget to increase the bolus doses if they are ineffective, as well as the
infusions
Sedation “failures”
Some patients can be challenging to sedate. Remove noxious stimuli if possible, try to
find a more comfortable mode of ventilation, assess for untreated pain and re-assess
targeted level of sedation. Ensure targets are met with boluses before increasing
infusions. Most patient require less than:
 midazolam 5 mcg/kg/min or 10 mg/h in older children adolescents
 morphine 100 mcg/kg/h
 fentanyl 5 mcg/kg/h
Some options for adjunctive pharmacological therapy:
 clonidine
 ketamine
 phenobarbital
 diphenhydramine
Usually best to add new drugs, once patient is stabilized try to decrease the original
drug(s) if possible.
Sedation Vacations
Sedation vacation refers to the practice of holding any sedative infusions daily and
restarting them at ½ the original dose. In adult ICUs this practice reduces the duration of
ventilation and ICU stay. This practice has not been evaluated in children but is
reasonable to consider sedation vacations in older children and adolescents. Younger
children should be assessed daily for their readiness to wean from the ventilator and for
the potential to decrease the dose of sedatives.
Delirium
The assessment of delirium in critically ill children is difficult. Low dose haloperidol or
chlorpromazine may be considered to treat delirium.
Adverse Effects
Hypotension: Reduce dose, change morphine to fentanyl, avoid propofol.
Pruritis: Intravenous diphenhydramine, change morphine to fentanyl
Constipation: Start all patients on continuous opiates on regular laxatives (lactulose
and/or senna) unless contraindicated.
Opiates
Choice of drug
Morphine is the PCCU standard. Use fentanyl if the patient is hemodynamically
unstable or if patients experience adverse effects with morphine. Fentanyl usually
causes less histamine release and usually causes less hypotension and pruritis. All
opiates provide equivalent analgesia at equivalent doses. These drugs have not been
compared in this population in any prospective trials. Both drugs accumulate in renal
dysfunction.
Equivalent doses
 Bolus doses: 0.1 mg/kg morphine = 1-2 mcg/kg of fentanyl
 Infusions: little information, morphine 40 mcg/kg/h = approximately fentanyl 1-2
mcg/kg/h
Starting doses:
 morphine 20-40 mcg/kg/h or fentanyl 1-2 mcg/kg/h
 neonates: 10 mcg/kg/h
Benzodiazepines
Choice of drug:
Lorazepam a better choice for intermittent dosing and in patients with renal or hepatic
dysfunction or patients on voriconazole. Midazolam is a better choice for acute
agitation, procedures and for infusions. After single doses midazolam is shorter acting
than lorazepam, but has active metabolites and is more likely to accumulate with
continuous infusion.
Starting doses
 Lorazepam or midazolam: 0.05-1.1 mg/kg (lorazepam max 4 mg, midazolam max 5
mg). Midazolam infusion 1-2 mcg/kg/min
 Older children and adolescents often require lower doses (on a mcg/kg basis) than
younger children. 0.5-1 mcg/kg/min is often a reasonable starting dose. Be aware of
the dose in mg/h, most patients need less than 5 mg/h initially and rarely require
more than 10 mg/h.
NSAIDs
All NSAIDs provide equivalent analgesia at appropriate doses. We used ibuprofen for
enteral use and ketorolac if IV administration is required. Do not use in patients with
coagulopathies, thrombocytopenia, gastrointestinal or other bleeding, recent orthopedic
or spinal surgery, renal dysfunction or those at higher risk of renal dysfunction.
Chloral Hydrate
Because of its slow onset of action, chloral hydrate should be given regularly, not on an
as needed basis. Adverse effects include bradycardia, arrhythmias and accumulation
with prolonged use.
Propofol
Propofol can used for procedural or short term sedation, but is not appropriate for longer
term sedation in the PCCU because of safety concerns. It can cause significant
hypotension and is best avoided in hemodynamically unstable patients.