methoxyflurane [Penthrox] Flashcards
Classification
Penthrox
inhaled fluorinated hydrocarbon volatile anesthetic
INDICATIONs
Penthrox
EMR
- self-administered - moderate to severe pain in conscious, hemodynamically stable pts
CONTRAINDICATIONs
Penthrox
- children <18 year
- NOT hemodynamically stable
- Inadaquate understanding/lack of cooperation
- DLOC or head inj
- hx sig. renal impairment (e.g. reduced renal output)
- hx liver dysfunction 2nd to previous halogenated anesthetic
- hx // genetic hx of malignant hyperthermia
- dx muscular dystrophy
- pregnancy, intended pregnancy, breast-feeding
- Current use of tetracycline antibiotic
CHECK mnemonic
CONTRAINDICATIONs
Penthrox
C - Cardiac instability // respiratory depression
H - Hypersensitivity
E - Established dx of malignant hyperthermia
C - Consciousness (i.e. ALOC)
K - Kidneys - signs of kidney failure/renal impairment
Dosage - Adult
Penthrox
EMR
3mL via inhaler
repeat x 1 @20mins
MAX dose - 6mL
ensure patient exhales through carbon filter
Pharmacodynamics
Penthrox
- u/k but fast acting
Pharmacokinetics
Penthrox
Inhaled
onset - 1-3 mins (8-10 breaths)
duration - ~25mins/3mL dose; 3-5min after D/C
elimination - metabolized by the liver and excreted by the lungs
Warnings // Precautons
Penthrox
- always have carbon filter attached during use
- fill chamber outside when possible
- tx in well-ventilated space (i.e. pt’s home, outdoors)
- close cab partition, cab fan on high, set pt compartment exhaust on high
EMR//paramedic exposure MAX 3 dose = 9mL/24hrs
ADVERSE EFFECTs
Penthrox
- ALOC (drowsiness)
- cough - pause use for persistent coughing
- discomfort - odour/taste
- hypotension & bradycardia (rare)
- nausea // vomiting
- susceptibility // suggestibility w/ decreased inhibition
OVERDOSE
Penthrox
- irreversible nephrotoxicity
no more than 6mL in 24hrs, no more than 15mL in 7days
