Transcript Pharmacology

Pharmacology
Introduction to Seattle Fire’s
Medications
Route of Administration
• How do you give the
medication?
• Where does it go?
• What are the affector
organs?
Routes of Administration
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Oral
Sublingual
Inhalation
Transdermal / Topical
Rectal
Parenteral
Oral
ASA
• Most drugs enter Portal circulation- “First Pass”
metabolism
Sublingual
Nitroglycerine
• Oral admin: 90% of nitroglycerine is cleared with
a single pass through the liver
• Sublingual goes to systemic circulation
directly
• Rapid onset, low risk of infection,
bypasses liver and harsh stomach acids
Inhalation
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MDI- Albuterol
Administration to the site of action
Less systemic absorption
Rapid onset
Requires ventilation by the patient or us…
Topical / Transdermal
?? What meds ??
• Slow onset of absorption
• Affected by location and type of skin
• What about heating pads?
Rectal
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?? What Meds ??
Does not require an IV
Rapid onset
50% of blood returns bypasses portal
circulation
What does that mean?
Parenteral
• Intravenous (IV)
– Usually drugs that can’t be given IV
• Can’t be absorbed or first pass destroys too much
– Rapid onset and maximizes control over
circulating levels
– May cause• Infection, hemolysis, too high of a serum level with
too high of administration, too fast
Parenteral
• Intramuscular (IM)
– Drug absorption is slower
– Allows for a sustained dose over an extended
period of time
– May cause
• Pain with injection, tissue necrosis at site,
infection, scar tissue deposition
Parenteral
• Subcutaneous (SC)
– Even slower drug absorption
– Works when minute amounts of medication
are needed to be delivered over a long period
of time
– Examples?
Adenosine- Antiarrhythimic
Mechanism of Action
• Naturally occurring nucleoside
• In the AV node it:
– Decrease conduction velocity
– Prolongs refractory period
– Decreases automaticity
Dose
• 6mg then 12 mg
Adv Side Effects
• Transient or possibly prolonged heart block
Onset / Duration
• Immediate onset- duration 30 seconds
Adenosine- Antiarrhythmic
Concentration
• 6mg/2cc
Route
• Rapid IVP, near central circulation
Indication
• SVT
Contraindications
• 2nd, 3rd degree heart block
• Persantine (dipyridamole USP) requires you to decrease the dose
Albuterol- Class
Mechanism of Action
• B2 agonist- stimulates bronchodilation of
smooth muscle
Dose
• 1 puff every 30 seconds to affect
Adv Side Effects
• Tachycardia, anxiety, HTN, convulsions
Onset / Duration
• Onset- 5-15 min
• Duration- 3-6 hrs
Albuterol- Class
Concentration
• 17g / 200 puffs- 90mcg / puff
Route
• Metered dose inhalor
Indication
• Acute bronchospasm (rescue inhaler)
Contraindications
• Prior reactions or sensitivity to albuterol, tachycardias
Aminophylline- Methylxanthine
Bronchodilator
Mechanism of Action
• Increases intracellular cAMP (which increase catecholimine release
and affect) and is a adenosine receptor antagonist (which then
inhibits bronchospasm)
Dose
• 5-7mg/kg- at 25mg a minute
Adv Side Effects
• Headache, nausea, chest pain, convulsions
Onset / Duration
• Varies- 15 min
Aminophylline- Class
Concentration
• 250mg / 10 mls
Route
• IV infusion
Indication
• Bronchospam, Asthma, COPD
Contraindications
• HTN, Tachycardia,
Anectine- Class
Mechanism of Action
• Succinylcholine attaches to somatic muscle
fiber receptor site depolarizing the junction.
Unlike acetlycholine it is not broken down
quickly so it remains antagonizing the receptor.
Dose
• 1.5mg / kg
Adv Side Effects
• Paralysis but no sedation, hyperkalemia,
malignant hyperthermia
Onset / Duration
• Onset 30 sec to 1 min
• Duration 3-5 min
Anectine- Class
Concentration
Route
Indication
• RSI
Contraindications
• Patients at risk for hyperkalemia- Renal Failure/Dialysis, prolonged
crush injuries, patients with history of milignant hyperthermia
ASA- Class
History
• In 1980 alone 36,000 tons were consumed
Mechanism of Action
• Platelet aggregate inhibitor by blocking Thromboxane A2
• ACS:
– New England Journal- “51% reduction in mortality” when used
for patients with angina (N Engl J Med 1983; 309:396–403.)
Dose
• 324mg PO
Adv Side Effects
Onset / Duration
ASA- Class
Concentration
• 81mg tablet
Route
• Oral
Indication
• ACS
Contraindications
• Ulcers, bleeding, chickenpox- Reye’s syndrome
Atropine- Antimuscarinic Agent
Atropine- Antimuscarinic Agent
Mechanism of Action
• Blocks the muscarinic receptor
site preventing acetylcholine from
stimulating it
Dose
• Varies- 0.5 to 1mg with max dose
2mg in adults? Peds: 0.02mg/kg
with minimum dose .1mg. Why?
Adv Side Effects
• Drying of secretions, tachycardia,
blurred vision
Onset / Duration
• Onset 2-4 minutes
• Duration 4 hours
Atropine- Antimuscarinic Agent
Concentration
• 1mg in 10mls
Route
• IV/IO/ET
Indication
• Bradycardia, organophosphate poisonings,
Contraindications
• 3rd degree heart blocks, glaucoma
Benadryl- Antihistamine
Mechanism of Action
• Blocks H1 histamine receptor sites
Dose
• 25-50mg
Adv Side Effects
• Drowsiness, hypotension, palpitations, headache
Onset / Duration
• Onset- varies with administration, but rapidly
• Duration- 3-4 hours
Benadryl- Class
Concentration
Route
Indication
Contraindications
Calcium Chloride
Mechanism of Action
• Critical mineral and electolyte
Dose
• 1g
Adv Side Effects
• Syncope, cardiac arrest,
Onset / Duration
• Onset- rapid
• Duration- unk
Calcium Chloride- Class
Concentration
• 1g in 10 mls
Route
• IV
Indication
• ???
Contraindications
• Hypercalcemia, dig toxicity
Dextrose- Class
Mechanism of Action
Dose
Adv Side Effects
Onset / Duration
Dextrose- Class
Concentration
Route
Indication
Contraindications
Diazepam/Diastat- Benzodiazapine
Diazepam/Diastat- Benzodiazapine
Mechanism of Action
• In conjunction with GABA increases intracellular chloride levels
hyperpolarzing the nerve cell
Dose
Adv Side Effects
Onset / Duration
Diazepam/Diastat- Class
Concentration
Route
• IV
• PR… any concerns here?
Indication
Contraindications
Diltiazem- Class
Mechanism of Action
• Decrease automaticity and depolarization of AV
nodal tissue, with some smooth muscle
relaxation.
Dose
Adv Side Effects
• Hypotension, bradycardia
Onset / Duration
Diltiazem- Class
Concentration
Route
Indication
Contraindications
Epinephrine- Review
• Alpha Receptors- A for arms
• B1 Receptors- 1 heart
• B2 Receptors- 2 lungs
Epinephrine- Class
Mechanism of Action
• A mixed Alpha and Beta receptor site agonist
Dose
• Varies…
Adv Side Effects
Onset / Duration
Epinephrine- Class
Concentration
Route
Indication
Contraindications
Etomidate- Class
Mechanism of Action
• A potent hypnotic agent that induces general anesthesia without
analgesic properties and little hemodynamic compromise
Dose
• 20 mg in pts weighing 150-250lbs
• 0.2mg to 0.6mg / kg 100kg patient gets 20mg
Adv Side Effects
• Adrenal crisis
Onset / Duration
Etomidate- Class
Concentration
Route
Indication
Contraindications
Furosemide- Class
Mechanism of Action
• Loop diuretic
Dose
• 20mg-40mg or…
Adv Side Effects
• Hypotension, dehydration
Onset / Duration
Furosemide- Class
Concentration
• 40mg/4mls
Route
Indication
Contraindications
Levophed- Class
Mechanism of Action
• Potent catecholamine
Dose
• Titrate to affect: 8mg in 250mls
Adv Side Effects
• Tissue necrosis,
Onset / Duration
Levophed- Class
Concentration
• 4mg in 4mls
Route
• IV
Indication
• Acute hypotension, cardiogenic shock
Contraindications
Lidocaine- Class
Mechanism of Action
• Inhibits intracellular sodium rush
Dose
• 100mg IV or a drip rate of what?
Adv Side Effects
• Decreased LOC, convulsions, bradycardia
Onset / Duration
• ??
Lidocaine- Class
Concentration
• 100mg in 5mls
• 2g in 250mls
Route
• IV
Indication
Contraindications
Midazolam- Benzodiazepine
Mechanism of Action
• Works in conjunction with GABA receptor site to increase influx of
chloride to hyperpolarize the nerve cell.
Dose
Adv Side Effects
Onset / Duration
Midazolam- Benzodiazepine
Concentration
Route
Indication
Contraindications
Mag Sulphate- Class
Mechanism of Action
• Relaxes smooth muscle and stabilizes cell membranes.
Dose
• Depends 4gm over 20 minutes for eclampsia, 1-2gm IV for cardiac
arrest
Adv Side Effects
Onset / Duration
Mag Sulphate- - Class
Concentration
Route
Indication
• Eclampsia, refractory V-Fib, polymorphic V-tach, bronchospasm
Contraindications
• Heart blocks..
Morphine- Narcotic
Mechanism of Action
• Narctotic analgesic
Dose
Adv Side Effects
Onset / Duration
Morphine- Narcotic
Concentration
Route
Indication
Contraindications
Narcan- Narcotic antagonist
Mechanism of Action
Dose
Adv Side Effects
Onset / Duration
Narcan- Narcotic antagonist
Concentration
Route
Indication
Contraindications
Nitroglycerine- Nitrate
Mechanism of Action
• Causes peripheral vascular vasodilation
Dose
• 0.4mg SL
Adv Side Effects
• Hypotension, headache
Onset / Duration
Nitroglycerine- Nitrate
Concentration
Route
Indication
Contraindications
• Inferior wall MIs that have right ventricular involvement
Oxytocin- Hormone
Mechanism of Action
Dose
• 10u in 10mls of LR
• 40u in 250mls of D5W
Adv Side Effects
Onset / Duration
Oxytocin- Hormone
Concentration
Route
Indication
Contraindications
Phenobarbital- Barbiturate
History
• The barbiturates were formerly the mainstay of treatment to sedate
the patient or to induce and maintain sleep.
• Today, they have been largely replaced by the benzodiazepines,
primarily because barbiturates induce tolerance, drug-metabolizing
enzymes, physical dependence, and are associated with very
severe withdrawal symptoms.
• May cause coma in toxic doses.
Phenobarbital- Barbiturate
Mechanism of action
• The sedative-hypnotic action of the barbiturates is due to their
interaction with GABAa receptors, which enhances GABAergic
transmission. The binding site is distinct from that of the
benzodiazepines.
• Barbiturates potentiate GABA action on chloride entry into the
neuron by prolonging the duration of the chloride channel openings.
Dose
• 260 mg Peds- May see very high doses
Adv Side Effects
• Sedation – Coma, bradypnea
Onset / Duration
• Duration- 4-6 hours to days
Phenobarbital- Barbiturate
Concentration
Route
Indication
Contraindications
Phenylephrine- Sympathomimetic
Mechanism of Action
• Potent Alpha agonist
Dose
• Titrate to affect
Adv Side Effects
• Slow HR, necrosis with tissue infiltration
Onset / Duration
Phenylephrine- Sympathomimetic
Concentration
• 10mg in 250mls
Route
• IV
Indication
• PSVT, neurogenic shock
Contraindications
• Left ventricular dysfunction
Procainamide- Antiarrhythmic
Mechanism of Action
• Potent Na channel blocker
Dose
• 100mg IVP for Plan A, 2mg a minute post arrest
• 20-30mg a minute for non-arrest antiarrhythmic dose up to 17mg/kg
or QRS widens greater than .08
Adv Side Effects
• Hypotension, nausea, widening of QT
Onset / Duration
Procainaminde- Class
Concentration
Route
Indication
Contraindications
• Torsades, heart blocks
Rocuronium- Non-depolarizing
Paralytic
Rocuronium- Non-depolarizing
Paralytic
Mechanism of Action
• This drug block cholinergic transmission between motor nerve
endings and the nicotinic receptors on the neuromuscular end plate
of skeletal muscle
Dose
• Induction-1.2mg/kg
• Control- 0.2mg/kg
Adv Side Effects
• Increased PVR, HTN
Onset / Duration
• Onset 1 min
• Duration 40 min
Rocuronium- Class
Concentration
Route
Indication
Contraindications
Sodium Bicarb- Electrolyte / Base
Mechanism of Action
• Acts as a base to correct acidosis
Dose
Adv Side Effects
• Tissue necrosis with inflitration
Onset / Duration
Sodium Bicarb- Class
Concentration
• 8.4% 50meq/50mls
Route
• IV
Indication
Contraindications
• Precipitates with Calcium
• Alkalosis