Use Of Sympathomimetic Agents Research Articles

EFFICIENCY OF TRANSPULMONARY THERMODILUTION IN THE OPTIMIZATION OF INTENSIVE TREATMENT IN PATIENTS WITH SEVERE NOSOCOMIAL PNEUMONIA

Objective: to evaluate the efficiency of transpulmonary thermodilution (TPTD) for the choice of measures to correct hemodynamics in patients with severe nosocomial pneumonia (NP). Subjects and methods. The investigation enrolled 107 NP patients admitted to an intensive care unit (ICU). Group 1 patients were intensively treated in accordance with a protocol for hemodynamic correction during early goaldirected therapy for sepsis. In Group 2, infusion thera py and sympathomimetic agents were prescribed depending on the results of TPTD. Results. Patients in both groups did not differ in the examined clinical and laboratory indicators. On day 1 of intensive therapy, in Group 2 (a TPTD controlled intensive treatment group) the prescription of sympathomimetic drugs was virtually twice more active than in Group 1; and the value of positive hydrobalance was, twice less. In 5 days, the frequency of use of sympathomimetic agents had no intergroup differences and, in 7 days became less in Group 2 patients. After the therapy patients in Group 2 did not require substantial amounts of infusion and great positive hydrobalance, resulting in lower central venous pressure (CVP) values. After 5 days of intensive therapy, the positive hydrobalance in Group 2 patients was 5 times less and on day 7 this indicator became negative. There were no intergroup differences in CVP on day 1; however, this indicator was higher in Group 1 patients from day 2 to the end of the followup period. At days 5—7, Group 2 patients exhibited elevated SvO2 values and hypolactatemia. At day 3, the SOFA severity was somewhat higher in Group 2 than in Group 1, then substantially reduced and on days 5—7 it was 2—2.5 scores lower in Group 2 than in Group 1. The mortality in ICU was 49% and 33% in Groups 1 and 2, respectively (χχ2=3.899; pConclusion. The determination of infusion amounts and indications for the use of sympathomimetic drugs on the basis of the integrated assessment of global enddiastolic volume index, cardiac index, and total peripheral vascular resistance index results in improved clinical outcomes in mechanically ventilated patients with severe NP. This approach ensures the use of sympathomimetic agents and to avoid hypervolemic loading.

Experience (mostly negative) with the use of sympathomimetic agents for weight loss.

Sympathomimetic agents have a poor history of long-term success in the treatment of obesity. From earlier experiences with amphetamine and its analogs, to more recent drugs with direct effects on adrenergic receptors or indirect effects from release of catecholamines or inhibition of reuptake, cardiovascular toxicity (strokes and cardiac arrhythmias) has been the major concern. These concerns also extended to food supplements containing ephedra alkaloids and may require consideration for current supplements containing the sympathomimetic drug, synephrine.

A case of postpartum cerebral angiitis and review of the literature

To better characterize postpartum cerebral angiitis (PPCA). We present a case of PPCA in which a 34-year-old G6P5104 underwent a normal vaginal delivery and developed PPCA. She had no signs or symptoms of gestational hypertension or preeclampsia. She had a history of migraines and received methylergonovine at delivery. She represented postpartum with headache and hypertension. The patient had characteristic findings of cerebral angiitis on imaging, and was diagnosed with PPCA. She was treated with nimodipine and steroids. She was monitored with transcranial Dopplers. In reviewing the literature, we found 23 cases of PPCA. We found that none had proteinuria, most were hypertensive, and all presented with headache. Use of sympathomimetic agents, particularly among those with migraines, may increase risk of PPCA.

Xenon as a Component of Anesthetic Maintenance for Early Activation of Patients after Myocardial Revascularization

Objective: to make a complex analysis of the efficacy of xenon as the major agent in maintaining anesthesia during early activation of patients operated on under extracorporeal circulation for coronary heart disease. Subjects and methods. Forty-two patients aged 59±3 years were examined. A total of 3±0.2 coronary arteries were shunted. General anesthesia was induced and maintained by propofol and fentanyl under extracorporeal circulation. Anesthesia was maintained by xenon inhalation in the preperfusion and postperfusion periods. General anesthesia was combined with high (Th3—Th4) epidural anesthesia in 10 cases. Results. During xenon inhalation, the central hemodynamic parameters were maximally steady-state both before and after extracorporeal circulation. The coronary perfusion conditions estimated from the coronary perfusion gradients were stable. The study of the conditions for coronary perfusion and the values of myocardial demand showed the persistence of their balance (r=0.55—0.83; p<0.05). With the use of epidural anesthesia as a component of maintenance, there was a two-fold increase (p<0.05) in the use of sympathomimetic agents. Lower Pa02 after initiation of xenon inhalation and, accordingly, decreased Fi02 were not associated with worse Pa02/Fi02 and increased intrapulmonary blood shunting; there were no changes in blood oxygen-transport function. Emergence from anesthesia occurred 9±1.2 min after the termination of xenon delivery and failed to be accelerated when epidural anesthesia was applied. The latter could reduce the inhaled concentration of xenon from 59.2±0.5 to 51.5±0.5% (p<0.05) and the dosage of fentanyl from 2.9±0.15 to 2.1±0.26 ^g/kg/hr <p<0.°5). The use of xenon as a basic anesthetic has prospects during early activation after myocardial revascularization under extracorporeal circulation. The advantage of xenon is the absence of negative effects on central hemodynamics and the presence of conditions for coronary perfusion in patients with coronary heart disease. This mode of maintenance provides not only an effective anesthetic protection, but also emergence from anesthesia in the range of 3 to 25 minutes after the end of operations, which allows one to make an early activation in the operating suite in more than 90% of cases. Key words: xenon, xenon anesthesia, early activation after surgery under extracorporeal circulation, anesthesia in patients with coronary heart disease.

Hyperadrenergic states

To review the physiologic and pathophysiologic hyperadrenergic states and the pharmacologic use of sympathomimetic agents. Pharmacologic and physiologic studies in experimental animals and humans. Plasma catecholamines are increased in a variety of clinical situations. Following major injury, catecholamines act to support vital organ perfusion and mobilize fuel substrates. However, with surgical trauma and during acute medical illnesses, such as myocardial infarction, catecholamine-induced physiologic changes can interact with underlying disease processes to result in clinically significant complications. Exogenous catecholamines are used to treat a variety of medical conditions, including anaphylaxis and various shock states. Available sympathomimetic agents differ in their availability to stimulate different subpopulations of adrenergic receptors. These differences permit the astute clinician to achieve specific physiologic end-points. Finally, plasma catecholamines are increased in patients with pheochromocytoma. This latter condition provides insights into the long-term effects of catecholamine excess. Based on knowledge of the pharmacology of sympathomimetic agents and the physiologic consequences of adrenergic receptor stimulation, it is possible to prevent undesirable catecholamine effects and to utilize these agents to achieve desired therapeutic goals.

Drug-related arrhythmias during therapy of congestive heart failure.

It is now recognized that ventricular and supraventricular arrhythmias are serious complications of congestive heart failure. There are four possible drug-related mechanisms: diuretic-induced electrolyte imbalance; digitalis-induced arrhythmias; use of sympathomimetic agents; and drug interactions with digoxin. In selecting optimal therapy for congestive heart failure all these drug interactions need to be borne in mind.

Cromolyn in extrinsic and intrinsic asthma

Cromolyn sodium was evaluated in 30 patients with intrinsic bronchial asthma and in 29 patients with extrinsic bronchial asthma using a double-blind crossover method. Each patient was studied during a base line, placebo, and cromolyn period. Daily evaluation was performed with regard to upper respiratory tract symptoms, lower respiratory tract symptoms, oral medication scores, use of sympathomimetic agents by aerosolization and peak expiratory flow rates measured 5 times a day. Weekly evaluation consisted of a physician's evaluation and a timed vital capacity. At the end of each test period spirometry, airway resistance and an exercise tolerance test were performed. Evaluation of the intrinsic asthmatic patients revealed significant improvement during the cromolyn period as compared to the placebo and base line periods with regard to the daily recorded variables and the physician's evaluation. Study of the other parameters showed no significant trend. Evaluation of the use of cromolyn in extrinsic bronchial asthma revealed no general trends for any of the parameters measured.