Emergency drugs used in anaesthesia

5 drugs majorly used by anaesthesia department with their basic pharmcology and how it is prepared.

1. EMERGENCY DRUGS KRISTINA PRADHAN INTERN

2. EMERGENCY DRUGS ATROPINE ADRENALINE MEPHENTERMINE EPHEDRINE XYLOCARD

3. ATROPINE CLASS: ANTICHOLIGERNIC DRUGS. BACKGROUND: A tertiary amine belladonna alkaloid, has a high affinity for muscarinic receptors.

4. ATROPINE MOA : binds competitively, preventing acetylcholine from binding to those sites Atropine acts both centrally and peripherally. Duration of action: Its general actions last about 4 hours except when placed topically in the eye, where the action may last for days

5. . ORGAN ACTION THERAPEUTIC USE EYE Dilation of pupils(MYDRIASIS) Blurring of near vision(CYCLOPLEGIA); Dry eye Ophthalmic: permits the measurement of refractive errors without interference by the accommodative capacity of the eye. Shorter-acting antimuscarinics (cyclopentolante and tropicamide) have largely replaced atropine due to prolonged mydriasis. GASTROINTESTINAL Antispasmodic Gastric motility is reduced, hydrochloric acid production is not significantly affected URINARY BLADDER Reduce hypermotility states of urinary bladder. Occasionally used in enuresis among children.

6. ORGAN ACTION THERAPEUTIC USE Heart low doses— brady cardia . (due to central activation of vagal efferent outflow-- result from blockade of the M1 receptors on the inhibitory prejunctional (or presynaptic) neurons-- permitting increased acetylcholine release. Higher doses -- M2 receptors on the SA node are blocked-- and the cardiac rate increases . (requires at least 1 mg of atropine) Bradycardia and partial heart block Secretions Sweat gland; salivary gland; lacrimal gland: Drying effect. Antisecretory .

7. ATROPINISATION IN OP POISONING

8. ATROPINISATION - Start with 0.05mg/kg in children 0.6-2mg i.v. , repeat 10-25 min. Until atropinisation obtained.; Ta chycardia D ' s " D elirium (disorientation) D rowsiness D ilated pupils (The mydriasis along with cyclopegia causes blurring of vision) D ryness of mouth D ry, hot skin

9. ADVERSE EFFECTS

10. PREPARATION Available( ampule): 1ml=0.6mg Dose: 0.01-0.02mg/kg Bradyarythmia : 0.04mg/kg Onset: 1-2 min Duration of Action: 20-30 min(i.v) 2-3 hrs (i.m.)

11. ADRENALINE Class :Direct acting sympathomimetic drugs. It interact with both alpha and beta receptors. At low dose , beta effect ( vasodilatation) on vascular system predominant. At high dose , alpha effect (vasoconstriction) are strongest

12. MODE OF ACTION Increase contractility of myocardium( Inotropic Effect , beta1 action) Increase HR( Choronotropic Effect ,beta 1 action) So, Increase In CO leads to Increase BP

13. ADRENALINE INDICATION ADVERSE EFFECTS CONTRAINDICATION BRONCHOSPASM CNS EFFECTS: ANXIETY, HEADACHE, TENSION, TREMOR. HYPERTHYROIDISM: INCREASED ADRENERGIC RECEPTOR ON VASCULATURE—HYPERSENSITIVE RESPONSE ANAPHYLACTIC SHOCK HEMORRHAGE: MARKED ELEVATION OF BP—CEREBRAL HEMORRHAGE COCAINE: PREVENT RE-UPTAKE OF CATECHOLAMINES—LONGER PERIOD OF TIME. GLAUCOMA(2%) PULMONARY EDEMA IN ANESTHETICS : TO INCREASE DURATION OF LOCAL ANESTHESIA.

14. DOSING In cardiac arrest 1 mg (10 mL 1:10,000 solution) IV push every 3 to 5 minutes. If this fails, higher doses of epinephrine (up to 0.2mg/kg) are acceptable but not recommended (there is growing evidence that it may be harmful) In anaphylaxis: 3-5mcg/kg

15. PREPARATION Available in Ampule at concentration: 1mg/ml(1:1000) Preparation : 100mcg/ml 10mcg/ml

16. MEPHENTERAMINE Class : Sympathomimetic ( Mixed action adrenergic agonist) Mechanism of action : - Acts indirectly by releasing norepinephrine from its storage sites and directly by exerting a slight effect on alpha and beta-1 receptors and a moderate effect on beta-2 receptors mediating vasodilation. Causes increased CO; also elicits slight CNS effects.

17. INDICATION AND DOSING INDICATION DOSING Hypotension due to anesthesia IV, Adults: 30-45 mg; 30-mg doses may be repeated as required; or, IV infusion, Adults and children: 0.1% (1 mg/mL) mephentermine in D5W with the rate of infusion and duration dependent on response. IV, Pediatric: 0.4 mg/kg (12 mg/m 2 ) as a single dose. Prophylaxis of hypotension in spinal anesthesia. IM, Adults: 30-45 mg 10-20 min before anesthesia. IM, Pediatric: 0.4 mg/kg (12 mg/m 2 ) as a single dose. Haemorrhage (only as emergency treatment until blood or blood substitutes can be given). Not recommended, but IV infusion of 0.1% in D5W may maintain BP until blood volume is replaced.

18. PREPARATION Available: 1ml=30mg Preparation: 1ml+4ml NS= 6mg/ml

19. EPHEDRINE Class : Sympathomimetic ( Mixed action adrenergic agonist) Action: longer duration of action; excellent oral absorption and penetrates into cns . Elimination: unchanged in urine.

20. EPHEDRINE Mechanism of action : Stimulates both alpha-and beta-receptors, causing increased heart rate, enhanced cardiac output and increased BP. Raises systolic and diastolic blood pressure by vasoconstriction and cardiac stimulation. Also causes bronchodilation but is less effective than epinephrine.

21. DOSING AND PHARMACOKINETICS Onset:30-60sec Duration of action: 60min Available: 1ml=30mg DOSAGE: 3-6 mg I.V.

22. SOME COMMON SIDE EFFECTS OF ADRENERGIC AGONISTS.

23. XYLOCARD Class : Antiarrhythmics class I B Mechanism of action: Sodium channel blocker : It acts by passing through the nerve membrane to attach or block the sodium conducting ion channels thereby inhibiting the nerve impulses.

24. ONSET OF ACTION:45-90 SECONDS DOSING: INDICATION: DURATION: 10-20 MINS 1.5-2MG/KG FOLLOWED BY INFUSION AT A RATE OF 1-4 MG/MIN. VENTRICULAR TACHYARRYTHMIA. AVAILABLE AS LOXICARD: 2% : 1ML=20MG

25. REFERENCE http://depts.washington.edu/opchild/images/ach.jpg- http://www.lifehugger.com/moc/828/Atropinization_signs_symptoms http://www.healthdigest.org/topics/category/1403-mephentermine-sulfate-dosage-interactions-side-effects-how-to-use-MEPHERTERMINE DOSING. LIPPINCOTT PHARMACOLOGY AJAY YADAV- SHORT TEXTBOOK OF ANAESTHESIA.