Lidocaine Amiodarone

Drug interactions Serious and/or life-threatening drug interactions could occur between amprenavir and amiodarone, lidocaine (systemic), tricyclic antidepressants, and quinidine. Concentration monitoring of these agents is recommended if these agents are used concomitantly with amprenavir. 

Amiodarone, lidocaine, and procainamide are commonly used antiarrhythmics for conversion in VF. Of these, amiodarone is the antiarrhythmic agent recommended first. In the Amiodarone versus Lidocaine in Ventricular Emergency (ALIVE) trial, patients administered amiodarone had a better rate of survival to hospital admission than those... 

A recommendation for a specific antiarrhythmic agent of first choice does not exist. Amiodarone, lidocaine, and procainamide are the available options. 

Cardiovascular Torsade de pontes has been attributed to cisapride 10 mg tds in a 36-year-old woman, in association with low serum potassium and magnesium concentrations [S ]. She had recurrent episodes, which required 50-70 defibrillation shocks per day, while several antidysrhyth-mic agents, including bretylium, phenytoin, isoprenaline, amiodarone, lidocaine, and magnesium sulfate, were ineffective. When cisapride was withdrawn the episodes of torsade de pointes resolved within a day. 

For PVCs of purely cardiac origin drugs to suppress ventricular irritability, such as amiodarone, lidocaine, procainamide... 

Consider giving such antiarrhythmics as amiodarone, lidocaine, magnesium, and procainamide. 

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. 

Patients with mild or no symptoms can be treated initially with antiarrhythmic drugs. IV amiodarone is now recommended as first-line therapy in this situation. Procainamide or lidocaine given IV is a suitable alternative. Synchronized DCC should be delivered if the patient s status deteriorates, VT degenerates to VF, or drug therapy fails. 

Lidocaine can be considered an alternative to amiodarone in patients with VF/ PVT, The initial dose is 1-1,5 mg/kg IV. Additional doses of 0.5-0.75 mg/kgcan be administered at 5-to 10-minute intervals to a maximum dose of 3 mg/kg if VF/PVT persists. 

The purpose of antiarrhythmic drug therapy after unsuccessful defibrillation and vasopressor administration is to prevent the development or recurrence of VF and PVT by raising the fibrillation threshold. However, the role of antiarrhythmics is limited because clinical evidence demonstrating improved survival to hospital discharge is lacking. Only amiodarone and lidocaine are recommended in the 2005 guidelines for CPR and ECC. 

The enzyme is the principal participant in N-demethylation reactions where the substrate is a tertiary amine. The list of substrates includes erythromycin, ethylmor-phine, lidocaine, diltiazem, tamoxifen, toremifene, verapamil, cocaine, amiodarone, alfentanil and terfenadine. Carbon atoms in the allylic and benzylic positions, such as those present in quinidine, steroids and cyclosporin A, are also particularly prone to oxidation by CYP3A4, a range of substrates is illustrated in Figure 7.10. 

Drugs that may affect amiodarone include hydantoins, cholestyramine, fluoroquinolones, rifamycins, ritonavir, and cimetidine. Drugs that may be affected by amiodarone include anticoagulants, beta-blockers, calcium channel blockers, cyclosporine, dextromethorphan, digoxin, disopyramide, fentanyl, flecainide, hydantoins, lidocaine, methotrexate, procainamide, quinidine, and theophylline. Drug/Lab test interactions Amiodarone alters the results of thyroid function tests, causing an increase in serum T4 and serum reverse T3 levels and a decline in... 

Transfer to sotalol from other antiarrhythmic therapy- Before starting sotalol, generally withdraw previous antiarrhythmic therapy under careful monitoring for a minimum of 2 to 3 plasma half-lives if the patient s clinical condition permits. Treatment has been initiated in some patients receiving IV lidocaine without ill effect. After discontinuation of amiodarone, do not initiate sotalol until the QT interval is normalized. 

Drugs that may be affected by fosamprenavir include the following Amiodarone, amitriptyline, benzodiazepines, calcium channel blockers, cisapride, contraceptives (oral), cyclosporine, ergot derivatives, HMG-CoA reductase inhibitors, imipramine, itraconazole, ketoconazole, lidocaine (systemic), methadone, pimozide, quinidine, rifabutin, sildenafil, tacrolimus, vardenafil, warfarin. 

O2, IV fluid, pressors, cyanide antidote kit, Cyanokit, sodium bicarbonate, anticonvulsants for Szs O2, charcoal, atropine (bradycardia), antiar-rhythmic (lidocaine, amiodarone)... 

According to recent ACC/AHA/ESC Guidelines (see Zipes et al., 2006), in patients with sutained VT, direct-current cardioversion is appropriate and most effective, and also intravenous procainamide (or ajmaline in some European countries) is recommended as a reasonable choice for initial treatment for sustained monomorphic VT in patients with acute coronary syndrome. Intravenous amiodarone or lidocaine may be reasonable chose as alternative treatment. 

Procainamide is effective against most atrial and ventricular arrhythmias. However, many clinicians attempt to avoid long-term therapy because of the requirement for frequent dosing and the common occurrence of lupus-related effects. Procainamide is the drug of second or third choice (after lidocaine or amiodarone) in most coronary care units for the treatment of sustained ventricular arrhythmias associated with acute myocardial infarction. 

Lopinavir/Ritonavir (Kaletra) [Anrirelroviral/Protease Inhibitor] Uses HIV Infxn Action Protease inhibitor Dose Adults. Tx naive 2 tab PO daily or 1 tab PO bid Tx experiencedpt 1 tab PO bid (T dose if w/ amprenavir, efavirenz, fosamprenavir, nelfinavir, nevirapine) Peds. 7-15 kg 12/3 mg/kg PO bid 15-40 kg 10/2.5 mg/kg PO bid >40 kg Adult dose w/ food Caution [C, /-] Numerous interactions Contra w/drugs dependent on CYP3A/CYP2D6 (Table VI-8) Disp Tab, soln SE Avoid disulfiram (soln has EtOH), metronidazole GI upset, asthenia, T cholesterol/triglycerides, pancreatitis protease metabolic synd Interactions T Effects Wl clarithromycin, erythromycin T effects OF amiodarone, amprenavir, azole andfungals, bepridil, cisapride, cyclosporine, CCBs, ergot alkaloids, flecainide, flurazepam, HMG-CoA reductase inhibitors, indinavir, lidocaine, meperidine, midazolam, pimozide, propafenone, propoxyphene, quinidine, rifabutin, saquinavir, sildenafil, tacrolimus, terfenadine, triazolam, zolpidem 1 effects Wl barbiturates, carbamazepine, dexamethasone, didanosine, efavirenz, nevirapine, phenytoin, rifabutin, rifampin, St. John s wort 1 effects OF OCPs, warfarin EMS Use andarrhythmics and benzodiazepines... 

A4 Acetaminophen, alfentanil, amiodarone, astemizole, cocaine, cortisol, cyclosporine, dapsone, diazepam, dihydroergotamine, dihydropyridines, diltiazem, ethinyl estradiol, gestodene, indinavir, lidocaine, lovastatin, macrolides, methadone, miconazole, midazolam, mifepristone (RU 486), paclitaxel, progesterone, quinidine, rapamycin, ritonavir, saquinavir, spironolactone, sulfamethoxazole, sufentanil, tacrolimus, tamoxifen, terfenadine, testosterone, tetrahydro-cannabinol, triazolam, troleandomycin, verapamil Barbiturates, carbamazepine, macrolides, glucocorticoids, pioglitazone, phenytoin, rifampin Erythromycin, 613-hydroxy cortisol... 

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