Send the page " " to a friend, relative, colleague or yourself. We do not record any personal information entered above. Barbiturates can lead to respiratory depression that can potentiate preexisting respiratory insufficiency; use methohexital cautiously, if at all, in patients with status asthmaticus or uncontrolled asthma. Because methohexital can cause dose-dependent respiratory depression, it should be used cautiously in patients with pulmonary disease states causing respiratory depression, dyspnea, severe pulmonary insufficiency, or airway obstruction. Barbiturates should be avoided in patients with bronchopneumonia. Use with close supervision in patients with sleep apnea or chronic obstructive pulmonary disease COPD.
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Send the page " " to a friend, relative, colleague or yourself. We do not record any personal information entered above. Barbiturates can lead to respiratory depression that can potentiate preexisting respiratory insufficiency; use methohexital cautiously, if at all, in patients with status asthmaticus or uncontrolled asthma.
Because methohexital can cause dose-dependent respiratory depression, it should be used cautiously in patients with pulmonary disease states causing respiratory depression, dyspnea, severe pulmonary insufficiency, or airway obstruction.
Barbiturates should be avoided in patients with bronchopneumonia. Use with close supervision in patients with sleep apnea or chronic obstructive pulmonary disease COPD. Also use cautiously in patients with a neuromuscular disease that may affect respiration such as myasthenia gravis, muscular dystrophy, or myotonia.
Laryngospasm is also common during barbiturate induction. Administration of methohexital requires a specialized care setting. Only use methohexital in hospital or ambulatory care settings that provide for continuous monitoring of respiratory e.
The use of methohexital requires an experienced clinician and personnel trained in resuscitative equipment use and skilled in airway management need to be immediately available. Also, for deeply sedated patients, a designated individual other than the practitioner performing the procedure should be present to continuously monitor the patient. Ultra-short-acting highly lipophilic barbiturate; faster onset of action and recovery time vs thiopental and twice as potent; used alone as an anesthetic for short procedures that are relatively painless, as an inducing agent, or as an adjunct to regional anesthesia.
Induction: 1—1. The dose required is variable range, 50— mg and provides about 5—7 minutes of anesthesia.
Alternatively, a continuous IV drip of the 0. For longer surgical procedures, gradual reduction in the administration rate is recommended. Prolonged administration may result in cumulative effects such as extended somnolence, protracted unconsciousness, and respiratory and cardiovascular depression. Respiratory depression in the presence of an impaired airway may lead to hypoxia, cardiac arrest, and death.
Methohexital was administered 22 times in one child and 28 times in the second child during daily radiation treatment. No recurrence of the behavior disturbance and no delay in discharge time were noted with methohexital as compared with propofol. Specific guidelines for dosage adjustments in hepatic impairment are not available; methohexital may be inappropriate for use in patients with severe hepatic impairment see Contraindications.
Specific guidelines for dosage adjustments in renal impairment are not available; it appears that no dosage adjustments are needed. Reconstituting instructions vary depending upon the route of administration. Directions for dilution should be followed exactly. Do not use diluents containing bacteriostatic agents. Freshly prepare and promptly use the solution.
Reconstituted solutions are chemically stable for 24 hours at room temperature. Visually inspect parenteral products for particulate matter and discoloration prior to administration whenever solution and container permit.
Use of preanesthetic medication is generally advisable. Do not administer intra-arterially as platelet aggregation and thrombosis distal to the site of injection may occur. The resulting necrosis can lead to gangrene and possibly amputation. Administer only in hospital or ambulatory care settings that provide for continuous monitoring of respiratory i.
For deeply sedated patients, a designated individual, other than the practitioner performing the procedure, should be present to continuously monitor the patients.
Do not mix in the same syringe or simultaneously administer intravenously through the same needle with acid solutions such as atropine sulfate, metocurine iodide, and succinylcholine chloride. Solubility of the soluble sodium salts of barbiturates is maintained only at relatively high basic pH. Higher concentrations markedly increase the incidence of muscular movements and irregularities in respiration and blood pressure.
Reconstitute the the mg vial with 20 ml diluent or the mg vial with 50 ml diluent. If using the 2. When the first dilution is made with the 2. To prepare a 0. Reconstitution for IM injection: Sterile water for injection should preferably be used as the diluent; 0. Intramuscular injection: Inject into a well developed muscle.
Aspirate prior to injection to avoid injection into a blood vessel. Reconstitution for rectal administration: Sterile water for injection should preferably be used as the diluent. Rectal Administration: Administer as a retention enema. Generic: - Store at controlled room temperature between 68 and 77 degrees F Brevital: - Discard unused product within 24 hours of opening bottle - Store at controlled room temperature between 68 and 77 degrees F.
NOTE: As with all potent anesthetic agents and adjuncts, methohexital should be used only in hospital or ambulatory care settings that provide for continuous monitoring of respiratory i. Also, personnel trained in equipment use and skilled in airway management should be assured. For deeply sedated patients, a designated individual other than the practitioner performing the procedure should be present to continuously monitor the patients. Avoid methohexital use in patients who have a previous history of barbiturate hypersensitivity.
Barbiturates can cause severe and potentially fatal reactions that are preceded by skin eruptions. Caution should be used when administering the drug to patients who may be predisposed to allergic reactions. Therapy should be prescribed only after critical benefit-to-risk appraisal in patients with a history of adverse hematologic i. Skin reactions can precede potentially fatal hypersensitivity reactions; exfoliative dermatitis has resulted in fatalities.
A history of hypersensitivity reactions should be obtained for a patient and the immediate family members. Barbiturate hypersensitivity reactions have been reported in patients who previously experienced hydantoin hypersensitivity e.
Phenytoin, carbamazepine, and phenobarbital are all metabolized to hydroxylated aromatic compounds via the cytochrome P hepatic oxidative enzymes; arene oxide intermediates are formed during metabolism and are thought to be responsible for cross-sensitivity among these anticonvulsants in susceptible individuals. Some individuals may have a reduced ability to detoxify the intermediate toxic metabolites e. However, studies of familial reactions have also shown that allergies to 1 anticonvulsant may not translate to allergies to others.
There is no way to predict with certainty which patients will exhibit cross-sensitivity. Methohexital is contraindicated for use in patients with latent or manifest porphyria such as acute intermittent porphyria, variegate porphyria, or a history of barbiturate-induced porphyria, the result of barbiturate induction of the enzymes involved in porphyrin synthesis. Methohexital should be used with caution in patients with adrenal insufficiency Addison's disease , renal disease, myxedema, uremia, or severe anemia because these disease processes can prolong and potentiate the hypnotic effects of methohexital.
Use methohexital cautiously in patients with extreme obesity. Methohexital, especially in higher or prolonged doses, should be used with extreme caution in patients with mental status changes, major depression, or suicidal ideation because the CNS-depressant effects of methohexital may exacerbate these conditions. Barbiturates potentiate preexisting circulatory depression.
Other induction agents should be considered in patients with cardiac disease, congestive heart failure, peripheral vascular disease, severe hypotension or hypertension, or shock.
Following induction, temporary hypotension and tachycardia may occur. The ability of the liver to demethylate and oxidize methohexital can be compromised in patients with hepatic disease. Methohexital should be used with extreme caution in this patient population.
Alternative induction agents should be considered. Geriatric patients are usually more sensitive to the sedative effects of barbiturates.
After administration of methohexital for surgical procedures, the elderly may take longer to recover cognitive and psychomotor functions. In addition, elderly patients are more likely to have an age-related reduction in hepatic function and may require a lower dose. It is not known if elderly patients will respond differently than younger patients to methohexital.
Elderly subjects may have conditions in which methohexital should be used cautiously such as COPD, severe hypertension or hypotension, preexisting circulatory depression, myocardial disease, congestive heart failure, or severe anemia. Caution should be exercised in debilitated patients or in those with impaired function of respiratory, circulatory, renal, hepatic, or endocrine systems.
In general, dose selection for the elderly should be initiated at the low end of the dosage range and titrated slowly to the lowest possible effective dose. Because methohexital can cause drowsiness and a decreased level of consciousness, there is a higher risk of falls, particularly in the elderly, with the potential for subsequent severe injuries. Repeated or lengthy use of general anesthetic and sedation drugs during surgeries or procedures in neonates, infants, and children younger than 3 years, including in utero exposure during the third trimester, may have negative effects on brain development.
Consider the benefits of appropriate anesthesia in young children against the potential risks, especially for procedures that may last more than 3 hours or if multiple procedures are required during the first 3 years of life. It may be appropriate to delay certain procedures if doing so will not jeopardize the health of the child.
No specific anesthetic or sedation drug has been shown to be safer than another. Human studies suggest that a single short exposure to a general anesthetic in young pediatric patients is unlikely to have negative effects on behavior and learning; however, further research is needed to fully characterize how anesthetic exposure affects brain development.
Methohexital should be used cautiously in patients with a history of a seizure disorder. Partial seizures may be elicited in susceptible individuals, particularly pediatric patients. Also, status epilepticus may occur in susceptible patients during abrupt discontinuation of barbiturates in patients with seizure disorders; methohexital should be used with extreme caution in patients with status epilepticus.
Methohexital may cause blurred vision, drowsiness, or dizziness after surgery or procedures. Patients should be released from the hospital or clinic in the company of a responsible adult. Patients should be instructed to avoid driving or operating machinery or performing other hazardous tasks for 8 to 12 hours following methohexital administration. Avoid ethanol intoxication; ethanol ingestion or coadministration with other CNS depressants can magnify CNS depression and the risk for respiratory depression.
There are no adequate or well-controlled studies of methohexital in pregnant women. Animal reproduction studies have not revealed evidence of harm to the fetus or impaired fertility. Although long-term use of methohexital is not expected, chronic exposure to other barbiturates during pregnancy has been associated with major fetal malformations, hemorrhage at birth, and addiction.
A retrospective study revealed that in utero exposure to barbiturates was associated with intelligence deficits. Barbiturates readily cross the placental barrier and are distributed throughout fetal tissues with highest concentrations found in the placenta, fetal liver, and brain. Fetal blood concentrations approach maternal blood concentrations after parenteral administration. Repeated use of barbiturates during the third trimester can cause physical dependence in the neonate.
Neonates with chronic barbiturate exposure in utero may experience an acute withdrawal syndrome, including seizures and hyperirritability, with an onset up to 14 days after birth.
However, aldosterone also has important extrarenal actions which are mediated via the activation of mineralocorticoid receptors in the heart, blood vessels and brain. Recent experimental and clinical findings indicate that aldosterone is an independent risk factor for cardiovascular disease. In fact, an elevated plasma aldosterone level is associated with detrimental effects on the cardiovascular system, including endothelial dysfunction, cardiovascular fibrosis, hypertrophy and inflammation, heart failure, sympathetic nervous system activation, stroke, and renal dysfunction. Moreover, aldosterone receptor antagonists have been shown to reduce the risk of progressive target organ damage in patients with hypertension and heart failure. Eplerenone is a new selective aldosterone receptor antagonist that has been recently approved for use in patients with left ventricular systolic dysfunction and clinical evidence of heart failure following acute myocardial infarction.
Características farmacológicas de los ARA-II. ¿Son todos iguales?
Pablo de Olavide University. These interactions can affect the antihypertensive drugs, altering their therapeutic efficacy and causing toxic effects. The aim of this study was to conduct a review of available data about interactions between antihypertensive agents and food. Methods: The purpose of this review was to report an update of main findings with respect to the interactions between food and antihypertensive drugs by way of a search conducted in PubMed, which yielded a total of articles initially. Results: After excluding different articles, which were not focusing on the specific objective, the main results refer to interactions between antihypertensive drugs and food in general as well as between antihypertensive agents and grapefruit juice.