Labetalol (Normodyne, Trandate)
Class: b -blocker
Use: Treatment of mild to severe HTN. IV for hypertensive
emergencies.
Action: Blocks a 1, b
1 and b 2 receptor sites with an a
to b blockade ration of 1:3 (oral) and 1:7
(IV). Also inhibits neuronal reuptake of norepinephrine
Cardiac Effect:
Administration Routes: PO, IV
Onset Time: PO: 30-120 mins. IV 2-5 mins
½ Life: 6-8 hrs
Metabolism -- Excretion: Extensive first-pass liver
conjugation -- <5% excreted in urine unchanged. Possible decreased
clearance in neonates/infants.
Side Effects: Orthostatic hypotension, CHF, arrhythmias, reduced
peripheral circulation, dyspnea, bradycardia, hepatotoxicity
Anesthesia Interactions:
|
Lidocaine (Xylocaine)
Class: Antiarrhythmic – Class I B (Na+ channel blocker)
Use: Local anesthetic for infiltration, peripheral nerve blocks,
and epidural spinal anesthesia. Acute treatment of ventricular
arrhythmias from myocardial infarction, cardiac manipulation, digitalis
intoxication.
Action: Blocks both the initiation and conduction of nerve
impulses by ¯ the neuronal membrane’s
permeability to Na+ ions (Na+ channel blocker), which results in
inhibition of depolarization with resultant blockade of conduction.
Suppresses automaticity of conduction tissue, by
electrical stimulation threshold of ventricle, HIS-Purkinje system, and
spontaneous depolarization of the ventricles during diastole by a direct
action on the tissues.
Cardiac Effect: Blocks inactive and active channels. More
selective to cells with long action potentials. ¯
APD.
Administration Routes: Topical, SC, Spinal, IV
Onset Time: 1.5-5 mins
½ Life: 2-10 mins. Terminal: 1.5-2 hrs
Metabolism -- Excretion: 90% in liver by CP450. --
Side Effects: Hypotension, heart block, arrhythmias,
cardiovascular collapse, dyspnea, respiratory depression or arrest
Anesthesia Interactions: Effect of succinylcholine may be
enhanced
|
Lisinopril (Prinivil, Zestril, Zestoretic)
Class: Angiotensin Converting Enzyme (ACE) Inhibitor
Use: Treatment of HTN, alone or in combination with other
antihypertensive agents. Adjunctive therapy in treatment of CHF
(afterload reduction)
Action: Competitive inhibitor of ACE. Prevents conversion of
angiotensin I to angiotensin II, a potent vasoconstrictor. Results in
lower levels of angiotensin II which causes an increase in plasma renin
activity and a reduction in aldosterone secretion.
Cardiac Effect:
Administration Routes: PO
Onset Time:
½ Life: 11-12 hrs
Metabolism -- Excretion: Nearly none. -- Almost
entirely excreted in urine as unchanged drug.
Side Effects: Hypotension, angina, tachycardia, peripheral edema,
hepatitis
Anesthesia Interactions:
|
Losartan (Cozaar)
Class: Angiotensin II receptor blocker
Use: Antihypertensive
Action: An angiotensin II receptor antagonist that blocks the
vasoconstriction and aldosterone secreting effects of angiotensin II by
selectively blocking the binding of angiotensin II to its receptor sites
found in many tissues, including VSM.
Cardiac Effect:
Administration Routes: PO
Onset Time:
½ Life:
Metabolism -- Excretion: Extensive first pass metabolism
(CP450) -- Mostly in feces. Some in urine.
Side Effects: Hypotension
Anesthesia Interactions:
|
Mannitol (Osmitrol)
Class: Osmotic Diuretic
Use: Reduction of increased intracranial pressure associated with
cerebral edema. Promotion of diuresis in the prevention and/or treatment
of oliguria or anuria r/t acute renal failure. Reduction of increased
intraocular pressure.
Action: Increases the osmotic pressure of glomerular filtrate,
which inhibits tubular reabsorption of water and electrolytes and
increases urinary output. Does not cross the Blood brain barrier.
Cardiac Effect:
Administration Routes: IV
Onset Time: Diuresis: 1-3 hrs. ICP: 15 mins.
½ Life: 1.1-1.6 hrs.
Metabolism -- Excretion: Minimal in liver to glycogen -- Unchanged
in urine
Side Effects: Circulatory overload, convulsions, hypovolemia,
pulmonary edema
Anesthesia Interactions:
|
Metoprolol (Lopressor, Toprol SL)
Class: Antiarrhythmic – Class II (b
-blocker -- Selective)
Use: Treatment of HTN and angina pectoris. Prevention of MI,
atrial fibrillation, flutter, symptomatic treatment of hypertrophic
subaortic stenosis.
Action: Selective inhibitor of b 1
receptors. Competitively blocks b 1
receptors, with little or no effect on b 2
receptors at doses <100 mg. Does not exhibit any membrane stabilizing
or intrinsic sympathomimetic activity
Cardiac Effect:
Administration Routes: PO, IV
Onset Time: PO: 20-30 mins. IV: 5 mins
½ Life: 3-4 hrs. ESRD: 2.5-4.5 hrs.
Metabolism -- Excretion: Significant first-pass in liver.
-- Urine (3-10% unchanged drug)
Side Effects: Bradycardia, arrhythmia
Anesthesia Interactions: If given IV in OR, can cause and
increase in effect in propofol, ketamine, fentanyl, sufentanil,
etomidate.
|
Milrinone (Primacor)
Class: Positive inotropic agent – Phosphodiesterase (PDE)
inhibitor
Use: Short-term IV therapy of CHF. Used for Ca2+ antagonist
intoxication
Action: Inhibits PDE III, the major PDE in cardiac and vascular
tissues. Inhibition of PDE increases cAMP potentiating delivery of Ca2+
to myocardial contractile systems resulting in a positive inotropic
effect. Inhibition of PDE in vascular tissue results in vasodilation
with no change in heart rate.
Cardiac Effect:
Administration Routes: IV
Onset Time:
½ Life: 136 mins – 2.7 hrs
Metabolism -- Excretion: 12% hepatic -- 85% unchanged
in urine.
Side Effects: Ventricular arrhythmias, hypotension, DP, V-Fib
Anesthesia Interactions:
|
Minoxidil (Rogaine, Loniten)
Class: Vasodilator
Use: Management of severe HTN resistant to treatment with other
antihypertensives. Treatment of baldness.
Action: Produces vasodilation by directly relaxing arteriolar
smooth muscle, with little effect on veins. Effects may be mediated by
cAMP. Stimulation of hair growth is secondary to vasodilation, increased
cutaneous blood flow and stimulation of resting hair follicles.
K+ efflux by activating the K+/ATP channels.
Cardiac Effect:
Administration Routes: PO, Topical
Onset Time: 30 mins
½ Life: 3.5-4.2 hrs
Metabolism -- Excretion: 88% hepatic glucuronidation -- 12%
excreted unchanged in urine.
Side Effects: EKG T-wave changes, tachycardia, CHF, edema
Anesthesia Interactions:
|
Nicardipine (Cardene)
Class: Ca2+ Channel blocker
Use: Dihydropyridines (DHP). Chronic stable angina. Management of
essential HTN, migraine prophylaxis. CHF.
Action: Inhibits Ca2+ from entering the "slow channels"
or select voltage-sensitive areas of VSM and myocardium during
depolarization, producing peripheral and coronary vasodilation.
Increases myocardial O2 delivery in patients with vasospastic angina.
Closed channel blocker.
Cardiac Effect:
Administration Routes: PO, IV
Onset Time:
½ Life: 2-4 hrs
Metabolism -- Excretion: Extensive first-pass in liver. --
As metabolites in urine
Side Effects: Tachycardia, pedal edema
Anesthesia Interactions:
|
Nifedipine (Adalat, Procardia)
Class: Ca2+ Channel blocker
Use: Dihydropyridines (DHP). Angina, hypertrophic cardiomyopathy,
HTN (sustained release only), pulmonary HTN
Action: Inhibits Ca2+ from entering the "slow channels"
or select voltage-sensitive areas of VSM and myocardium during
depolarization, producing peripheral and coronary vasodilation.
Increases myocardial O2 delivery in patients with vasospastic angina.
More vascular than Diltiazem. Closed channel blocker.
Cardiac Effect:
Administration Routes: PO, SL
Onset Time: PO: 20 mins. SL: 1-5 mins
½ Life: 2-5 hrs. Cirrhosis: 7 hrs
Metabolism -- Excretion: Liver to inactive metabolites -- Urine
Side Effects: Hypotension, peripheral edema, dyspnea, tachycardia
Anesthesia Interactions: Fentanyl may increase hypotension.
|
Nimodipine (Nimotop)
Class: Ca2+ channel blocker (Dihydropyridines – DHP)
Use: Improvement of neurological deficits due to spasm following
subarachnoid hemorrhage from ruptured congenital intracranial aneurysms
in patients who are in good neurological condition postictus
Action: Inhibits Ca2+ from entering the "slow channels"
or select voltage-sensitive areas of VSM and myocardium during
depolarization, producing peripheral and coronary vasodilation.
Increases myocardial O2 delivery in patients with vasospastic angina.
Has a greater effect on cerebral arteries than other arteries. Closed
channel blocker.
Cardiac Effect:
Administration Routes: PO
Onset Time:
½ Life: 3 hrs
Metabolism -- Excretion: Liver -- 32% feces. 50% in
urine.
Side Effects: Hypotension. Edema, tachycardia, bradycardia
Anesthesia Interactions: Fentanyl may increase hypotension.
|
Nitroglycerin (Nitrostat)
Class: Nitrate. Vasodilator
Use: Treatment of angina pectoris. IV for CHF. Pulmonary HTN.
Hypertensive emergencies. Control of blood pressure in perioperative
HTN. Controlled hypotension during surgical procedures
Action: Reduces cardiac oxygen demand by decreasing left
ventricular pressure and systemic vascular resistance. Dilates coronary
arteries and improves collateral flow to ischemic regions.
Cardiac Effect:
Administration Routes: SL, PO, IV, Topical, Transdermal, Spray
Onset Time: IV: Immediate. SL: 1-3 mins. Transdermal: 40-60 mins.
½ Life: 1-4 mins
Metabolism -- Excretion: Extensive first-pass -- Inactive
metabolites in urine.
Side Effects: Hypotension, reflex tachycardia, bradycardia
Anesthesia Interactions:
|
Nitrosprusside (Nipride, Nitropress, Sodium
Nitrosprusside, SNP)
Class: Nitrate - Vasodilator
Use: Management of hypertensive crises. CHF. Used for controlled
hypotension to reduce bleeding during surgery
Action: Causes vasodilation by action on VSM (by generation of
NO), thus ¯ peripheral resistance.
CO by ¯ afterload. Has little effect on
other smooth muscle. Produces a baroreceptor mediated reflex
tachycardia. Alters pulmonary V/Q, promoting shunting
Cardiac Effect:
Administration Routes: IV
Onset Time: 30-60 seconds
½ Life: <10 minutes. Thiocyanate: 2.7-7 days
Metabolism -- Excretion: Converted to cyanide ions in
bloodstream. -- Thiocyanate renally eliminated
Side Effects: Hypotension, cyanide poisoning, hypoxia
Anesthesia Interactions: To treat cyanide poisoning use 100% O2,
NaCO3, Sodium nitrate (competes with SNP), Vitamin B12 (binds with Cn-)
|
Pindolol (Visken)
Class: b -blocker (Partial agonist)
Use: Management of HTN
Action: Blocks both b1 and b2
receptors and has mild intrinsic sympathomimetic activity. Has negative
inotropic and chronotropic effects and can significantly slow AV nodal
conduction. Partial agonist. Has ISA (Intrinsic sympathomimetic
activity) properties.
Cardiac Effect:
Administration Routes: PO
Onset Time:
½ Life: 2.5-4 hrs
Metabolism -- Excretion: 60-65% liver -- 70% hepatic.
30% renal (35-50% unchanged drug)
Side Effects: CHF, arrhythmia, reduced peripheral circulation,
bradycardia
Anesthesia Interactions:
|
Prazosin (Minipress)
Class: a -blocker (Peripherally
acting)
Use: Treatment of HTN, severe CHF. Reduce mortality in post MI
patients with left ventricular dysfunction. May reduce vasospasm.
Decrease ventricular arrhythmias due to cardiac ischemia.
Action: Competitively inhibits postsynaptic a
1 receptors which results in dilation of arterioles and a decrease in
TPR and BP. Also dilates veins and therefore decreases cardiac preload.
Cardiac Effect: Minor ¯ in
contractility
Administration Routes: PO
Onset Time: 1-2 hrs
½ Life: 2-4 hrs
Metabolism -- Excretion: Primarily in liver. -- Primarily
in bile and feces. 6-10% in urine as unchanged drug
Side Effects: Orthostatic hypotension, edema, no sympathetic
response.
Anesthesia Interactions:
|
Procainamide (Procan, Promine)
Class: Antiarrhythmic – Class I A (Na+ channel blocker)
Use: Treatment of ventricular tachycardia, PVC’s PAT’s, and
A-fib. Prevention of recurrence of VT, PSVT, A-fib or A-flutter.
Action: ¯ myocardial excitability and
conduction velocity and may ¯ contractility,
by the electrical stimulation threshold of
ventricle, HIS-Purkinje system and through direct cardiac effects. Open
channel blocker (frequency drug block).
APD. ¯ rate of rise of AP.
Cardiac Effect:
Administration Routes: PO, IM, IV
Onset Time: IM 10-30 mins
½ Life: Procainamide: Children: 1.7 hrs. Adults: 2.5-4.7 hrs.
NAPA: Children: 6 hrs. Adults: 6-8 hrs.
Metabolism -- Excretion: Acetylation in liver to produce
N-acetyl procainamide (NAPA) (active metabolite) -- Urinary excretion
(25% as NAPA)
Side Effects: Tachycardia, arrhythmias, AV block, QT
prolongation, widening QRS, hypotension, pleural effusion
Anesthesia Interactions: Increased effect of skeletal muscle
relaxants, quinidine and lidocaine and neuromuscular blockers
(succinylcholine)
|
Propranolol (Inderal)
Class: Antiarrhythmic – Class II (b
-blocker -- Non-selective)
Use: Management of HTN, angina and arrhythmias. Prevention of MI,
migraine. Symptomatic treatment of hypertrophic subaortic stenosis.
Action: Nonselective b -blocker.
Competitively blocks response to b 1 and b
2 stimulation which results in decreases in HR (by decreasing AV nodal
conduction), myocardial contractility, blood pressure, and myocardial
oxygen demand.
Cardiac Effect:
Administration Routes: PO, IV
Onset Time: 1-2 hrs.
½ Life: Children: 3.9-6.4 hrs. Adults: 4-6 hrs.
Metabolism -- Excretion: Extensive first-pass effect.
Metabolized to active and inactive compounds. -- 96-99% in urine
Side Effects: Bradycardia, CHF, hypotension, bronchospasm
Anesthesia Interactions:
|
Spironolactone (Aldactone)
Class: K+ Sparing Diuretic
Use: Management of edema associated with excessive aldosterone
excretion. HTN. Primary hyperaldosteronism. hypokalemia. Treatment of
hirsutism. Cirrhosis of liver accompanied by edema or ascites.
Action: Competes with aldosterone for receptor sites in the
distal renal tubules, increasing Na+, Cl- and H2O excretion while
conserving K+ and H+ ions. May block the effect of aldosterone on
arteriolar smooth muscle as well
Cardiac Effect:
Administration Routes: PO
Onset Time: Slow
½ Life: 78-84 minutes
Metabolism -- Excretion: In liver to multiple metabolites
including canrenone (active) -- Urinary and biliary excretion
Side Effects: Hypotension, edema, bradycardia, CHF
Anesthesia Interactions:
|
Timolol (Timoptic, Blocadren)
Class: b -blocker
Use: Ophthalmic dosage form used in treatment of elevated
intraocular pressure such as glaucoma or ocular hypertension. Orally for
treatment of HTN and angina and reduce mortality following MI and
prophylaxis of migraine.
Action: Blocks both b1 and b2
receptors, reduces intraocular pressure by reducing aqueous humor
production or possibly outflow. Reduces blood pressure by blocking
adrenergic receptors and decreasing sympathetic outflow, produces a
negative chronotropic and inotropic activity through an unknown
mechanism
Cardiac Effect:
Administration Routes: PO, Drops
Onset Time: 15-45 minutes
½ Life: 2-2.7 hrs
Metabolism -- Excretion: Extensive first pass in liver -- Urinary
excretion (15-20% as unchanged drug)
Side Effects: Bradycardia, dyspnea, arrhythmia, CHF
Anesthesia Interactions:
|
Triamterene (Dyrenium)
Class: K+ Sparing Diuretic
Use: Alone or in combination with other diuretic in treatment of
edema and HTN. Decreases K+ excretion caused by kaliuretic diuretics.
Action: Competes with aldosterone for receptor sites in the
distal renal tubules, increasing Na+, Cl-, and H2O excretion while
conserving K+ and H+ ions. May block the effect of aldosterone on
arteriolar smooth muscle as well
Cardiac Effect:
Administration Routes: PO
Onset Time: 2-4 hrs
½ Life: 100-150 minutes
Metabolism -- Excretion: --
Side Effects: Hypotension, edema, CHF, bradycardia, dyspnea
Anesthesia Interactions:
|
Urea (Carbamide)
Class: Osmotic Diuretic
Use: Reduction of intracranial or intraocular pressure.
Action: Elevates plasma osmolality, enhancing the flow of H2O
into extracellular fluid such as blood, and reducing intracranial and
intraocular pressure.
Cardiac Effect:
Administration Routes: IV
Onset Time: 1-2 hrs
½ Life:
Metabolism -- Excretion: Hydrolyzed in GI by bacterial
urease -- By kidneys.
Side Effects: Syncope, hypotension
Anesthesia Interactions:
|
Verapamil (Calan, Verelan)
Class: antiarrhythmic – Class IV (Ca2+ channel blocker)
(Diphenylalkalamine)
Use: (Diphenylalkalamine) Treatment of angina pectoris and HTN,
PSVT, atrial fibrillation, atrial flutter.
Action: Inhibits CA2+ from entering the "slow channels"
or select voltage-sensitive areas of VSM and myocardium during
depolarization, producing a relaxation of coronary VSM and coronary
vasodilation. Increases myocardial O2 delivery in patients with
vasospastic angina. Slows automaticity and conduction of AV node. Open
channel blocker. Most cardio-selective.
Cardiac Effect: Most cardio-selective. Negative inotrope.
Administration Routes: IV, PO
Onset Time:
½ Life: Infants: 4.4-6.9 hrs. Adults: 2-12 hrs.
Metabolism -- Excretion: Extensive firs-pass in liver -- 70%
excreted in urine (16% in feces.
Side Effects: Bradycardia, first, second or third degree AV
block, CHF, hypotension, peripheral edema
Anesthesia Interactions: Fentanyl may increase hypotension. Will
increase AV block because it increases [Dig].
|