Michael I. Greenberg

Blood Levels Following Intravenous and Endotracheal Epinephrine Administration

The blood levels of epinephrine and its metabolites which were obtained when the drug was given by both the intravenous (IV) and endotracheal (ET) routes were compared. Anesthetized dogs were subjected to radioactive epinephrine in doses of 0.005, 0.03, 0.06, and 0.09 mg/kg administered both intravenously and endotracheally. Blood levels were obtained at 0.25, 0.75, 1.5, 3, 5, 10 and 30 minutes following injection and analyzed by thin layer chromatography. The maximum measured concentration following IV injection was observed at 15 seconds. Epinephrine was rapidly metabolized with 20% of the original concentration detected at 5 minutes following IV injection. When the drug was given by the ET route, the maximum measured concentration was similarly observed at 15 seconds. Following ET installation, initial blood concentrations are sustained over a much longer period of time and 80% of the initial concentration was detected at 5 minutes. Maximum concentrations are approximately one-tenth of those achieved with an equal IV dosage. It is concluded that endotracheally and intravenously administered epinephrine rapidly reach maximum blood levels although there are differences in kinetics between the two routes.

Comparison of the pharmacological effects of epinephrine administered by the intravenous and endotracheal routes

Epinephrine in various dosages was administered to anesthetized dogs by intravenous and endotracheal routes. Both methods produced measurable effects on heart rate, blood pressure, and respiration. Tachycardia occurred more rapidly after endotracheal administration than after intravenous administration. Respiration appeared to be supported more advantageously with the larger endotracheal dosages. The maximum blood pressure rise was delayed only 60 seconds by the endotracheal route. With an endotracheally administered dose of ten times the intravenous dose, equal responses in blood pressure were obtained. However, when equal doses are compared, there is only a two to three fold increase with the intravenous route. The endotracheal route may be less toxic at higher doses, affording greater safety when large amounts of epinephrine are used. It is concluded that endotracheally administered epinephrine produces significant pharmacologic effects in anesthetized dogs.

Nanotechnology and nanotoxicology : A primer for clinicians

Nanotechnology is the manipulation of matter in dimensions <100nm. At this size, matter can take on different chemical and physical properties, giving the products characteristics useful to industry, medicine and technology. Government funding and private investors provide billions of research dollars for the development of new materials and applications. The potential utility of these technologies is such that they are expected be a trillion-dollar industry within the next 10 years.However, the novel properties of nanoengineered materials lead to the potential for different toxicity compared with the bulk material. The field of nanotoxicology is still in its infancy, however, with very limited literature regarding potential health effects. Inhalational toxicity is to be expected, given the known effects of inhaled fine particulate matter. However, the degree to which most nanoparticles will aerosolise remains to be determined. It has been proposed that dermal exposure will be the most relevant route of exposure, but there is considerably less literature regarding dermal effects and absorption. Less defined still are the potential effects of nanoproducts on fetal development and the environment.

Methamphetamine: History, Pathophysiology, Adverse Health Effects, Current Trends, and Hazards Associated with the Clandestine Manufacture of Methamphetamine

eveloped as an amphetamine derivative, methamphetamine quickly ecame a popular medication during the 1940s and 1950s, prescribed for variety of indications. Extensive diversion of methamphetamine during he 1960s and an increasing awareness of the adverse health effects ssociated with methamphetamine led to the withdrawal of most of the ndications for licit methamphetamine use and declines in legal producion of the drug. However, the illicit manufacture of methamphetamine ncreased to meet the demand for methamphetamine, and methamphetmine abuse has increased with variable geographic penetrance over the ast 30 years. Methamphetamine is an indirect sympathomimetic agent that is distinuished from amphetamine by a more rapid distribution into the central ervous system (CNS), resulting in the rapid onset of euphoria that is the esired effect for those abusing the drug. Increases in monoamine eurotransmission are responsible for the desired effects—wakefulness, nergy, sense of well-being, and euphoria—as well as the excess ympathetic tone that mediates many its adverse health effects. Methamphetamine is associated with adverse effects to every organ ystem. Although the most significant morbidity and mortality occur ecause of cardiovascular effects, such as myocardial infarction and ypertensive crisis, no organ system remains unscathed by methamphet-

Emergency department preparedness for the evaluation and treatment of victims of biological or chemical terrorist attack.

This study evaluated the preparedness of Emergency Departments (EDs) in the greater Philadelphia area to evaluate and treat victims of a terrorist biological or chemical agent release. All hospitals with EDs in the survey target area were included. A survey instrument consisting of 38 questions was mailed to the physician director of each ED. Fifty-four of 62 directors returned usable surveys. This represented an overall response rate of 88.5%. Deficiencies in preparedness were identified involving physician training and education, antidote stocking, written policies, interagency agreements, and decontamination facilities. The overall level of preparedness for hospital EDs responding to this survey was low based on a set of predetermined, implicit criteria. Comprehensive plans should be developed and implemented to remedy the identified deficiencies.

Endotracheal epinephrine in cardiorespiratory collapse

The endotracheal route for the administration of epinephrine has been studied extensively in dogs. There has been little in the medical literature to document the successful use of this technique in humans. The successful use of endotracheally administered epinephrine in two patients with cardiorespiratory collapse is reported. Specific points concerning endotracheal drugs are discussed and a set of guidelines for clinical use is offered.

Endotracheal naloxone reversal of morphine-induced respiratory depression in rabbits

In an emergency, intravenous access may be difficult to obtain rapidly. Alternate routes of administration for drugs are, therefore, desirable. Our study was performed to determine if naloxone could be efficacious in reversing morphine-induced respiratory depression in rabbits when administered using the endotracheal route. Our results indicate that naloxone administered in this fashion is effective in reversing morphine-induced respiratory depression in the rabbit. Mean minute ventilation was depressed to greater than half of resting baseline levels using morphine sulfate. Endotracheally administered naloxone reversed this respiratory depression and resulted in a greater than five-fold increase in mean minute ventilation above baseline levels. We concluded that endotracheal naloxone is efficacious in reversing morphine-induced respiratory depression in the rabbit. The endotracheal route may be an effective alternative for naloxone administration in man when rapid intravenous access is not obtainable.

Endotracheal epinephrine in a canine anaphylactic shock model.

This study was undertaken to determine if epinephrine administered endotracheally is as effective in treating anaphylactic shock as is intravenously administered epinephrine. An animal model of anaphylactic shock was produced in anesthetized dogs by the intravenous administration of histamine phosphate. Both the endotracheal and intravenous routes of epinephrine administration resulted in efficient and effective reversal of histamine-induced hypotension. At the doses employed, the intravenous administration of epinephrine resulted in the production of significantly (p less than 0.05) greater numbers of ventricular cardiac arrhythmias than did the endotracheal route of administration.

Baclofen Withdrawal Following Removal of an Intrathecal Baclofen Pump Despite Oral Baclofen Replacement

Intrathecal baclofen is used as a muscle relaxant and antispasmodic in cases of spasticity resulting from central nervous system trauma. The baclofen withdrawal syndrome may include hyperthermia, tachycardia, hypertension, seizures, altered mental status, and psychomotor agitation. We report a case in which the removal of a baclofen pump lead to the development of severe withdrawal symptoms despite oral baclofen replacement therapy. In order to avoid the development of withdrawal, adequate doses of GABA agonist agents should be administered immediately prior to, and following, baclofen pump removal.

Endotracheal administration of atropine sulfate

Atropine sulfate was successfully administered endotracheally to a 74-year-old patient suffering profound bradycardic cardiovascular collapse. Ninety seconds following endotracheal atropine administration, normal blood pressure and pulse were established. Therapeutic blood levels of atropine were documented following endotracheal administration. The endotracheal route for atropine administration appears to provide an effective alternative route of administration when intravenous access is difficult or impossible to establish rapidly.