History-   1840– DISCOVERY OF NITROUS OXIDE , DIETHYL ETEHR AND CHLOROFORM   1951– First halogenated  hydro carbon anaesthetic , fluroxene introduced – inflammable and had organ toxicity 1956 – halothane  clinically used 1960 – methyl flurane , methyl ether was first derivative – in clinical use devoid  of dysrhythmogenic effect with epinephrine , prolonged […]

Produced by adrenal medulla ACTIONS: DIRECT AGONIST OF ALPHA 1 ,2, BETA 1 AND 2 RECEPTOR. DOSE (mcg/kg/min) RECEPTOR ACTION SVR 10-30 beta May decrease 30-150 beta and alpha Variable >150 alpha and beta Increase   PROTOTYPE  DRUG. NATURAL FUNCTIONS- Increase myocardial contractility Increase heart rate Increase vascular and bronchial smooth muscle tone Increase glandular […]

Released from post ganglionic sympathetic nerve endings. Potent action on beta 1 alpha receptors . no action on beta 2 receptors. ACTIONS: Heart rate : variable, no change or increases if blood pressure is low. Contractility increases. Cardiac out put increases. Systemic vascular resistance increases. Peripheral vascular resistance increases. Off set by redistribution neural uptake […]

Cardioplegia solution is used to arrest the cardiac activity during cardiopulmonay bypass. Types- ST Thomas I (Maccarthy) Nacl-144mmol/l Kcl -20mmol/l Mgcl -16 Cacl2 -2.4 meq/l NaHco3- Procaine-1.0 pH – 5.5-7.0 osmolarity -300-320   ST Thomas II (Plegisol) Nacl -110 Kcl -16 Mgcl -16 Cacl2-1.2 NaHco3 -10 pH- 7.8 osmolarity -285-300   MYOCARDIAL PROTECTION STRATEGIES Anaesthetic […]

Classification: Group of compounds which selectively interfere with inward calcium ion movement across myocardial and vascular smooth muscle. Four classes- Class I: Phenyl alkyl amines: Verapamil Class II: 1 ,4 dihydroxy pyrimidines: Nifedipine Nicardipine Nimodipine Israpidine Felodipine Amlodipine Class III: Benzothiazines Diltiazem Class IV: Di aryl amino propyl amine Ether (Ltype) eg: bepridil   Mechanism […]

Nitroglycerin Structure Organic nitrate acts on venous capacitance. Route of administration Tablets- oral , buccal , transmucosal , lingual spray. Transdermal patch or ointment – 5 to 10mg. Over 24 hours provides sustained protection against myocardial ischaemia.   Mechanism of action Generates NO with acts as mediator resulting in peripheral vasodilators in presence of two […]

CLASSIFICATION OF ANTIARRHYTHMIC DRUGS- FOUR CLASSES.- APD action potential, ERP-Effective refractory period. Class I Antiarrhythmic are again subclassified in three groups. Electrophysiologic activity I A IB IC Phase O Decreased Slight effect Marked decreased depolarisation prolonged Slight effect Slight effect conduction Decreased Slight effect Markedly slowed ERP Increased Slight effect Slight prolonged APD Increased Decreased […]

CLASS III ANTIARRHYTHMIC DRUG- Chemical structure: ☛ Benzofuran derivative ☛ First line anti arrythmc derivative in cardio pulmonary resuscitation by ATSA in VT ☛ Effective prophylactically in preventing AF post operatively. ☛ Wide spectrum of effectiveness including supraventricular and preexcitation syndrome.   Actions: Increase APD Decrease the slope of diastolic depolarization(phase 4) with depressed SA […]

Quinidine Class IA prototype antiarrhythmic. Dextroisomer of quinine. Antimalerial and anti pyretic action. Pharmacological structure Obtained from Cinchana Plant. Twobasic Nitrogens. pK-10. Reduces Na ion  current by binding to open Na ion  channels resulting in depression of automaticity of ectopic foci. Available as sulphate ,gluconate. Quinidine sulphate is oral  prepn  commonly,can be available as IM. […]