Ventricular fibrillation lidocaine

Ventricular fibrillation should be terminated by electrical defibrillation. Alternatively, lidocaine can be injected intravenously. In cases with lower frequency, ventricular tachyarrhythmia class I diugs such as aj marine, flecainide or propafenone are more effective as a result of the use-dependence of lidocaine. For prophylaxis treatment, amiodarone or sotalol may be helpful or the implantation of a cardioverter-defibrillator system. Acute amiodarone (i.v. in higher doses) can also terminate ventricular tachyarrhythmias. This action, however, seems to be mediated by its INa-blocking side effects and not (or less) by its class III like effects. 

Unlabeled uses In pediatric patients with cardiac arrest, less than 10% develop ventricular fibrillation, and others develop ventricular tachycardia the hemodynamically compromised child may develop ventricular couplets or frequent premature ventricular beats. In these cases, administer 1 mg/kg lidocaine by the IV, intraosseous, or endotracheal route. A second 1 mg/kg dose may be given in 10 to 15 minutes. Start a lidocaine infusion if the second dose is required a third bolus may be needed in 10 to 15 minutes to maintain therapeutic levels. 

Pharmacology Therapeutic concentrations of lidocaine attenuate phase 4 diastolic depolarization, decrease automaticity and cause a decrease or no change in excitability and membrane responsiveness. Action potential duration and effective refractory period (ERP) of Purkinje fibers and ventricular muscle are decreased, while the ratio of ERP to action potential duration is increased. Lidocaine raises ventricular fibrillation threshold. AV nodal conduction time is unchanged or shortened. Lidocaine increases the electrical stimulation threshold of the ventricle during diastole. 

Lidocaine is the agent of choice for termination of ventricular tachycardia and prevention of ventricular fibrillation after cardioversion in the setting of acute ischemia. However, routine prophylactic use of lidocaine in this setting may actually increase total mortality, possibly by increasing the incidence of asystole, and is not the standard of care. Most physicians administer IV lidocaine only to patients with arrhythmias. 

Lidocaine Sodium channel (INa) blockade Blocks activated and inactivated channels with fast kinetics does not prolong and may shorten action potential Terminate ventricular tachycardias and prevent ventricular fibrillation after cardioversion IV first-pass hepatic metabolism reduce dose in patients with heart failure or liver disease Toxicity Neurologic symptoms... 

Bretylium is usually used in an emergency setting, often during attempted resuscitation from ventricular fibrillation when lidocaine and cardioversion have failed. 

VENTRICULAR FIBRILLATION (not responding to electrical defibrination) Lidocaine I. ... I Bretvlium Epinephrine... 

A patient who was treated with intranasal cocaine and submucosal lidocaine during general anesthesia developed ventricular fibrillation (SEDA-17,142). 

Although an intermediate endpoint is associated with clinical benefit/ this benefit may be more than offset by the adverse effects of drug therapy when the ultimate outcome is considered. For example/ ventricular fibrillation is associated with increased mortality in the setting of acute myocardial infarction. The demonstration that lidocaine effectively prevents ventricular fibrillation in myocardial infarction patients at first provided a rationale for treating these patients prophylactically with this drug (7). However/ subsequent meta-analyses of several studies by MacMahon (8) and Hine (9) indicated that this use of lidocaine therapy actually worsens patient... 

Lie KI, Wellens HJ, van Capelle FJ, Durrer D. Lidocaine in the prevention of primary ventricular fibrillation A double-blind, randomized study of 212 consecutive patients. N Engl J Med 1974 291 1324-6. 

Wyman MG, W5unan RM, Cannom DS, Criley JM. Prevention of primary ventricular fibrillation in acute myocardial infarction with prophylactic lidocaine. Am J Cardiol 2004 94 545-51. 

These are common after myocardial infarction. Their particular significance is that the R-wave (ECG) of an ectopic beat, developing during the early or peak phases of the T-wave of a normal beat, may precipitate ventricular tachycardia or fibrillation (the R-on-T phenomenon). About 80% of patients with myocardial infarction who proceed to ventricular fibrillation have preceding ventricular premature beats. Lignocaine (lidocaine) is effective in suppression of ectopic ventricular beats but is not often used as its addition increases overall risk. 

Infusions of 0.25% bupivacaine into pig coronary arteries caused ventricular fibrillation at lower rates of infusion than 0.25% bupivacaine with 1% lidocaine (10). The lidocaine/bupivacaine mixture did not have a greater myocardial depressant effect than bupivacaine alone. The authors suggested that when regional anesthesia requires high doses of local anesthetics, bupivacaine should not be used alone but in a mixture with lidocaine, and that lidocaine should be useful in the management of bupivacaine-induced ventricular fibrillation. 

Fujita Y, Endoh S, Yasukawa T, Sari A. Lidocaine increases the ventricular fibrillation threshold during bupivacaine-induced cardiotoxicity in pigs. Br J Anaesth... 

Cardiac dysrhythmias in digitalis overdose should be treated only if they are life-threatening. Phenytoin is probably the treatment of choice for ventricular tachydysrhyth-mias, but lidocaine or a beta-adrenoceptor antagonist, such as propranolol, are options. After an overdose of 300 tablets of digoxin (plasma digoxin concentration 50 ng/ml), recurrent ventricular fibrillation was successfully treated with bretylium tosylate (191). Sinus bradycardia may respond to atropine. 

A death due to ventricular fibrillation after 50 mg and another due to sinus arrest after 100 mg have been reported (SED-12, 255) (17). Two cases of ventricular fibrillation and cardiopulmonary arrest occurred after local infiltration of lidocaine for cardiac catheterization (SEDA-21,136). 

A 54-year-old woman who was given lidocaine, 200 mg intravenously, for ventricular fibriUation during cardiopulmonary bypass, had a tonic-clonic seizure (28). The seizure occurred immediately after the administration of hdocaine and was reheved by the intravenous administration of thiopental and midazolam. Her ventricular fibrillation responded to procainamide 1 g intravenously over 10 minutes. 

Weaver WD, Fahrenbruch CE, Johnson DD, Hallstrom AP, Cobb LA, Copass MK. Effect of epinephrine and lidocaine therapy on outcome after cardiac arrest due to ventricular fibrillation. Circulation 1990 82(6) 2027-34. 

Hansoti RC, Ashar PN. Atrioventicular block and ventricular fibrillation due to lidocaine therapy. Bombay Hosp J 1975 17 26. 

Plagiarized It is a common nightmare as the ambulance sits in heavy traffic, a person with a heart attack dies, often a victim of ventricular fibrillation, uncoordinated contraction of the heart muscle. Today, however, these early deaths can often be prevented by an injection into the patient s shoulder of a common heart drug called lidocaine, which may be administered by paramedics on the scene. 

Harrison EE. Lidocaine in prehospital countershock refractory ventricular fibrillation. Ann Emerg Med 1981 10 420M23. 96. 

ALIVE Amiodarone versus Lidocaine In pre-hospital Ventricular fibrillation Evalnation... 

Lidocaine (e.g., Xylocaine) Depresses automaticity of ectopic foci, increases conduction velocity of A-V node and His-Purkinje. Wolff-Parkinson-White, Ventricular tachycardia. Premature vent, depolarization. Ventricular fibrillation. CNS paresthesias, drowsiness, confusion, restlessness (at low doses). At high doses, seizures or disorientation. Cardiac depression (if given by rapid IV), arrhythmias. 

The HCP orders a lidocaine drip at 3 mg/min for a client who has just converted from ventricular fibrillation to normal sinus rhythm with multiple premature ventricular contractions (PVCs). The intravenous bag has 2 grams of lidocaine in 500 mL normal saline. How would the nurse set the intravenous rate ... 

Lidocaine is administered in ventricular fibrillation, but it is not administered first in a code. 

Ventricular fibrillation is a very common dysrhythmia in a code situation, and lidocaine is the drug of choice because it suppresses ventricular ectopy. 

For ventricular fibrillation, immediately apply direct-current countershock at 3-5 J/kg. Repeat twice if no response. Continue CPR if the patient is still without a pulse, and administer epinephrine, repeated countershocks, amiodarone, and/or lidocaine as recommended in advanced cardiac life support (ACLS) guidelines. 

A retrospective study, covering a 6-year period in 29 hospitals, identified 29 patients (27 available for review) who received lidocaine for prophylaxis or treatment of cocaine-associated myocardial infarction. No patient exhibited bradycardia, sustained ventricular tachycardia or ventricular fibrillation, and no patients died. ... 

---