Critical Care Flashcards
Morphine (narcotic)
Peak: 30 mins IV Duration: 3-7 hrs May cause histamine release and hypotensive response May cause respiratory suppression Decrease in GI motility
Fentanyl (narcotic)
Peak: 4 hours IV (nearly immediate onset)
Duration: 30-60 mins
May cause respiratory depression, drowsiness, sedation
Minimum CV depressing effects unlike morphine (drug of choice in hemodynamically unstable patients)
No histamine release
Rare bradycardia and chest wall rigidity if rapidly infused in large dose
Hydromorphone -aka Dilaudid (narcotic)
Peak: 20 mins IV
Duration: 4-5 hours
Alternative to morphine (semisynthetic opioid)
Like fentanyl, has less CV side effects and no histamine release
Side effects may include itching (pruritus), sedation, nausea
Ketamine (strong narcotic)
Peak: 30-60 mins
Half-life: 2-3 hours (duration can be unpredictable)
Usually used in addition to other pain control drugs to help control
Bolus dose may increase BP, HR, and CO, or bronchodilation
Cautions in patients with increased ICP…hallucinations may occur
Dexmedetomidine (strong narcotic)
Peak: 1-2 mins
Half-life: 2-3 hours
Sedative and analgesic properties
Continuous infusion, provides sedation without respiratory depression
May help with tolerance of mechanical ventilation
Narcotic reversal
Naloxone (Narcan)
Onset of 1-3 mins (IV), 10-15 (IM)
rebound sedation may occur
May cause withdrawal in patients with chronic narcotic use
Benzodiazepines (sedatives)
Most common are;
Midazolam (Versed) -more rapid onset, high cost
Diazepam (valium) -low cost, rapid onset, long half-life (36hrs)
Lorazepam (Ativan) -longer acting, low cost
Lipophilic
Diazepam (valium) (benzodiazepine)
Onset: rapid, 2-5 mins
Half-life: 20-120 hours
Intermittent dosing only, no infusion
Midazolam (Versed) (Benzodiazepine)
Onset: 2-5 mins
Peak: 5-30 mins (30-120 minute duration)
Fast onset, short duration
May accumulate in renal failure, so generally use avoided if so
Lorazipam (Ativan) (benzodiazepine)
Onset: 5-15 mins
Duration: 6-8 hrs
Less lipophilic=slower onset
Shown to be more cost effective and provides greater adequacy of sedation than midazolam (versed)
May be the preferred benzo in patients with renal failure
Reversal of benzodiazepines
Flumazenil (romazicon)
May precipitate seizures unresponsive to to benzos
Haloperidol (neuroleptic)
Used to treat extreme agitation and delerium (CNS depression)
Has antidopaminergic and anticholinergic effects
Onset: 3-20 mins
Max dose of 200mg
Used to treat ICU delirium
Propofol -aka Diprivan (anesthetic)
Onset: 30 seconds Duration: 3-10 mins CV and Resp depression (decreases SVR, BP, and HR in initial phase) Combined with morphine to control ICP Important to monitor triglycerides
Neuromuscular blocking agents (NMBA’s) (paralytics)
Depolarizing
-Mimic acetylcholine, initially results in fasciculations, prolongs depolarization at the NMJ. Causes paralyzation by inhibiting repolarization of the NMJ
Non-depolarizing
-Competitive antagonist to acetylcholine, most common type used. Bind to acetylcholine receptors at the NMJ and inhibit Ach’s action. Blocks transmission of nerve impulses (depolarization) causing paralysis.
Succinylcholine (Depolarizing paralytic)
4-6 minute duration of action per single administration
Complete blockade in 30-60 seconds
NO REVERSAL AGENTS, only time
Complications
K+ efflux, increasing serum potassium (may cause arrhythmias, CA)
malignant hyperthermia (hypermetabolic state of skeletal tissue)
Cisatracurium (Nimbex) (Non-depolarizing paralytic)
Duration: 40-60 mins
Onset: 2-3 mins
NOT eliminated by liver or kidney, may be best choice for patients with hepatic or renal failure
May be poor choice for patients with unstable ICP
Rocuronium (Zemuron) (Non-depolarizing paralytic)
Duration: 30-60 mins
Onset: 1-2 mins
Vecuronium (Norcuron) (Non-depolarizing paralytic)
Duration: 60-90 mins
Onset: 2-4 mins
Does not have vagolytic properties of pancuronium
Metabolized to minimally active metabolites
Not best choice for renal/hepatic failure
Pancuronium (Pavulon) (Non-depolarizing paralytic)
Duration: Long (120-180 mins)
Onset: 4-6 mins
Used for prolonged paralysis of MV patients in ICU
Side effects; tachycardia, increased CO, elevated MAP, vagolytic effects
Vasopressor (Levophed)
Norepinephrine (Levophed)
Catecholamine, strong vasoCONSTRICTOR, also increases both HR and contractility
Used to treat acute hypotension resulting from conditions such as MI, drug reactions, spinal anesthesia, and septicemia
FIRST CHOICE of vasopressor in sepsis
Vasopressor (Neo-synephrine)
Phenlyephrine (Neo-Synephrine)
Purely alpha agonist
Induces vasoconstriction in most vascular beds, elevates systolic and diastolic BP.
Does not increase HR or contractility
NOT recommended in septic shock unless Norepi is associated with serious arrhythmias or CO is low and BP is very low, or when other combinations have failed.
Vasopressor (Pitressin)
Vasopressin (Pritressin)
- Direct vasoconstriction without chronotropic/inotropic effects - Second line vasoconstrictor in addition to norepi, to increase BP or reduce the dose of Norepi - Low dose initially is ineffective in sepsis
Inotrope (Inotropin)
Dopamine
Precursor to norepinephrine
Dose between 5-20 produce inotropic and chronotropic effects and increase CO
Renal blood flow improvement secondary to increased CO
Alternative to norepinephrine in sepsis in patients with low risk of tachyarrhythmias
Inotrope (Dobutrex)
Dobutamine
Indicated for SHORT-term support in patients with decompensated heart failure due to depressed contractility
Does not stimulate dopamine receptors and it not metabolized to norepinephrine
Effects due to racemic components
Vasoconstrictive and vasodilatory effects
Epinephrine
Potent beta-1 adrenergic receptor activity
Moderate beta-2 and alpha-1 activity
Increases blood pressure by increasing cardiac index and peripheral vascular tone
Often used in septic shock second to norepi
Side effects include arrhythmias and increased splanchnic circulation
Drugs that induce metHB
Dapsone (antibacterial) and topical agents (benzocaine, lidocaine) most commonly the cause
Nitric oxide (pulmonary vasodilator)
Nitroprusside (vasodilator/antihypertensive)
Treatment usually methylene blue
Diuretics
P otassium-sparing (collecting duct) (spironolactone-ALDACTONE)
L oop (Ascending loop) (furosemide-LASIX)
O smotic (descending loop) (mannitol-ARIDOL)
C arbonic anhydrase inhibitors (proximal tubule) (acetazolamide)
T hiazides (Distal tubule) (hydrochlorothiazide-MICROZIDE)
Narcotic Analgesics
- Used to treat moderate to severe pain
- bind to opioid receptors in brain and SC
- most metabolized by liver and excreted in urine
- popular for drug abuse
- can develop a rapid tolerance with painful withdrawal
