Pharmacology

Article: Nitrous Oxide Review Nitrous oxide irreversibly oxidizes the cobalt ion in reduced vitamin B12. This inactivates vitamin B12, which is essential for the function of methionine synthetase. Methionine synthetase is necessary for the transmethylation of homocysteine to methionine. Methionine is an essential amino acid and thus its deficiency results in impaired DNA synthesis. Methionine […]

Beta-Blockers in Perioperative Care: Mechanisms, Benefits, and Clinical Considerations Beta-blockers play an important role in perioperative cardiovascular risk reduction and are widely used in patients undergoing surgical procedures. Their cardioprotective effects extend beyond simple heart rate control and include a range of physiologic mechanisms that improve myocardial efficiency, reduce arrhythmia risk, and stabilize hemodynamics. Understanding

Antiarrhythmics Adenosine ↑ K+ out of cells -> hyperpolarizing the cell and ↓ ICa, decreasing AV node conduction. Drug of choice in diagnosing/terminating certain forms of SVT. Very short acting (~ 15 sec). Effects blunted by theophylline and caffeine (both are adenosine receptor antagonists). Adverse effects include flushing, hypotension, chest pain, sense of impending doom,

Inducers (+) Substrates Inhibitors (–) Chronic alcohol use St. John’s wort Phenytoin Phenobarbital Nevirapine Rifampin Griseofulvin Carbamazepine Anti-epileptics Theophylline Warfarin OCPs Sodium valproate Isoniazid Cimetidine Ketoconazole Fluconazole Acute alcohol abuse Chloramphenicol Erythromycin (macrolides) Sulfonamides Ciprofloxacin Omeprazole Metronidazole

Dog bite: Augmentin. This antibiotic is bacteriocidal for the range and spectrum of human and animal bite pathogens including Staphylococcus species and Pasteurella multocida.

Tricyclic antidepressants, including specifically amitriptyline, have been suggested to be effective in alleviating pain in chronic pain syndromes and in reducing bruxism by an unknown mechanism. None of the distractors have been shown to decrease bruxism. SSRI’s may increase bruxism.   Tricylcic antidepressants (elavil) prevent the reuptake of catecholamines. Ketamine has sympathomimetic effects and will

Flumazenil and Narcan are used to reverse effects of benzodiazepines and narcotics, respectively. Atropine is an antimuscarinic and does not reverse deximedetomidine. Atipamezole is an alpha2-adrenoceptor antagonist with an imidazole structure. It rapidly reverses sedation/anesthesia induced by alpha2-adrenoceptor agonists. In humans, atipamezole at doses up to 30 mg produces no cardiovascular or subjective side effects,

Barbiturates have no effect on myocardial sensitization. They decrease myocardial contractility. Reflex tachycardia is common after an induction dose of barbiturate to compensate for the vasodilatation. Barbiturates are known to have severe effects associated with intra-arterial injection. This group is also responsible for porphyria in susceptible individuals.

Ketamine direct action on the myocardium is a negative inotropic effect. Its centrally mediated sympathetic responses (indirect activation of the sympathetic nervous system) usually override the depression. Ketamine causes an increase in circulating catecholamines, especially norepinephrine, by inhibiting reuptake at postganglionic sympathetic neurons.

Serotonin syndrome is characterized by confusion, agitation, tachycardia, fever, hyperreflexia, and myoclonus. Normeperidine is an active metabolite of meperidine metabolism and has a half-life of 15 to 30 hours in an adult. Normeperidine’s elimination is dependent upon renal function and can accumulate with high repeated dosages or in the presence of renal impairment. Serotonin antagonists,