Epinephrine respiratory effects

Desflurane is less potent than the other fluorinated anesthetics having MAC values of 5.7 to 8.9% in animals (76,85), and 6% to 7.25% in surgical patients. The respiratory effects are similar to isoflurane. Heart rate is somewhat increased and blood pressure decreased with increasing concentrations. Cardiac output remains fairly stable. Desflurane does not sensitize the myocardium to epinephrine relative to isoflurane (86). EEG effects are similar to isoflurane and muscle relaxation is satisfactory (87). Desflurane is not metabolized to any significant extent (88,89) as levels of fluoride ion in the semm and urine are not increased even after prolonged exposure. Desflurane appears to offer advantages over sevoflurane and other inhaled anesthetics because of its limited solubiHty in blood and other tissues. It is the least metabolized of current agents. 

It is believed that the mechanism of action of amphetamines lies in their ability to release epinephrine (adrenaline) and dopamine from presynaptic nerve endings, which stimulate the corresponding receptors in the CNS. It is also possible that they reduce neuronal uptake of amines as well as inhibit their degradation by monoaminoxidase (MAO). Characteristic of this series of compounds is the effect on the respiratory center, on the satiation center located in the hypothalamus, which leads to suppression of feelings of hunger, thus allowing analog of the examined compounds to be used as anorectics. 

Use cautiously in people with acute or chronic respiratory impairment, particularly children, because phenothiazines may suppress the cough reflex. If hypotension occurs, epinephrine is not recommended because phenothiazines may reverse its usual pressor effect and cause a paradoxical further lowering of blood pressure. Because these drugs have an antiemetic action, they may obscure signs of intestinal obstruction, brain tumor, or overdosage of toxic drugs. 

Death from SNA Intoxication appears to Involve both cardiovascular and respiratory systems. 2 SNA Increases the effects of pentobarbital on both respiration and heart rate. The depressant effects of SNA on the myocardium and on the Purklnje system are antagonized effectively by epinephrine, but not by Metrazol (pentylenetetrazol) and caffeine. Artificial respiration restored cardiac stability and regularity. It was suggested that SNA Interferes with oxygen utilization In animals. The circulatory and respiratory responses to SNA were considered to be mediated through the medulla oblongata. 2... 

Overdosage with clonidine causes bradycardia, hypotension, CNS depression, respiratory depression, hypothermia, apnea, and hypoventilation. Atropine sulfate is able to reverse bradycardia, and epinephrine, dopamine, or tolazine are effective in combating hypotension. 

Lidocaine is absorbed rapidly after parenteral administration and from the gastrointestinal and respiratory tracts. Although it is effective when used without any vasoconstrictor, epinephrine decreases the rate of absorption, such that the toxicity is decreased and the duration of action usually is prolonged. In addition to preparations for injection, an iontophoretic, needle-free drug-delivery system for a solution of lidocaine and epinephrine (lontocaine) is available. This system generally is nsed for dermal procedures and provides anesthesia to a depth of np to 10 mm. 

Epinephrine usually Is administered slowly by Intravenous (IV) Injection to relieve acute asthmatic attacks not controlled by other treatments. Intravenous Injection produces an Immediate response. Use of EPI with drugs that enhance cardiac arrhythmias (digitalis or quinidine) Is not recommended. Tricyclic antidepressants and MAO Inhibitors will potentiate the effects of EPI on the heart. Epinephrine should be used with caution In Individuals suffering from hyperthyroidism, cardiovascular disease, hypertension, or diabetes. Adverse effects Include palpitations, tachycardia, sweating, nausea and vomiting, respiratory difficulty, dizziness, tremor, apprehension, and anxiety. 

Certain respiratory tract irritants, including a number of fluorocarbons, can produce cardiac arrhythmias. Such effects may be attributed to the reduction of coronary blood flow, depression, or contractility and sensitization of the heart to epinephrine and several other factors. Many lipid-soluble substances can depress cardiac contractility. These include organic solvents, many general anesthetics, and aminoglycoside antibiotics. 

Dichlarotetralluoroethane (fluorocarbon 114, Freon 114 [CAS 76- 14-2]) Vapors may sensitize the myocardium to arrhythmogenic et-fects of epinephrine at modestly high air ieveis (25,000 ppm). Other effects at higher levels (100,000-200,000 ppm) include respiratory irritation and CNS depression. See also p 209. 1000 ppm 15,000 ppm Colorless gas with a mild ether-like odor. Thermal breakdown products include hydrogen chloride, hydrogen tiuoride, and phosgene. 

Epinephrine-induced cardiac arrhythmia was not induced in beagle dogs exposed by face mask to 5,000 or 10,000 ppm tetrachloroethylene (Reinhardt et al. 1973). This study was complicated by the dogs struggling, which could represent irritant effects of these high tetrachloroethylene concentrations on the upper respiratory tract. 

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