Brazilian Journal of Anesthesiology
https://bjan-sba.org/article/doi/10.1590/S0034-70942002000400007
Brazilian Journal of Anesthesiology
Scientific Article

Efeitos da efedrina sobre as funções cardiovascular e renal de cães sob anestesia com pentobarbital sódico

Effects of rphedrine on cardiovascular and renal function of dogs anesthetized with sodium pentobarbital

Rosa Beatriz Amorim; José Reinaldo Cerqueira Braz; Yara Marcondes Machado Castiglia; Pedro Thadeu Galvão Vianna; Norma Sueli Pinheiro Módolo

Downloads: 0
Views: 136

Resumo

JUSTIFICATIVA E OBJETIVOS: Com a perspectiva criada por algumas pesquisas de ações diferenciadas da efedrina sobre a função renal, dependendo da dose utilizada, e considerando-se as controvérsias ainda existentes a respeito dos seus efeitos sobre a função renal, esta pesquisa experimental tem como objetivo verificar se doses diferentes de efedrina determinam efeitos hemodinâmicos e renais diferenciados. MÉTODO: Em 32 cães anestesiados com pentobarbital sódico (PS), submetidos a preparação cirúrgica, cateterismo, monitorização, expansão do volume do fluido extracelular e respiração controlada, foi estudada a hemodinâmica cardiovascular e renal e a função renal. Os cães foram distribuídos aleatoriamente em quatro grupos: G controle (n = 8), com os cães permanecendo apenas sob o efeito do PS, G ef. 2 µg (n = 8), G ef. 10 µg (n = 8) e G ef. 100 µg (n = 8), com os cães recebendo efedrina nas doses respectivas de 2, 10 e 100 µg.kg-1.min-1. Os atributos cardiovasculares e renais foram estudados em 5 momentos: controle (M1 e M2), durante a infusão de efedrina (M3 e M4) e após a suspensão da infusão de efedrina (M5). RESULTADOS: Não houve diferença significante entre os grupos em relação aos atributos estudados. Em G ef. 2 µg houve aumento significante de freqüência cardíaca, fluxo sangüíneo aórtico, débito urinário e excreção fracionária de sódio. Em G ef. 10 µg houve aumento apenas da freqüência cardíaca e fração de filtração, enquanto em G ef. 100 µg ocorreu aumento de freqüência cardíaca, pressão arterial média, pressão venosa central, fluxo sangüíneo aórtico e hematócrito; por outro lado, ocorreu diminuição dos fluxos plasmático e sangüíneo renais e aumento da resistência vascular renal. CONCLUSÕES: A efedrina, dependendo da dose utilizada, apresenta ações hemodinâmicas e renais diferenciadas.

Palavras-chave

ANIMAL, DROGAS, HIPNÓTICOS, RIM

Abstract

BACKGROUND AND OBJECTIVES: Some studies have shown differentiated dose-dependent effects of ephedrine on cardiovascular and renal functions. This study aimed at verifying whether different ephedrine doses determine differentiated hemodynamic and renal effects. METHODS: Cardiovascular and renal hemodynamics and renal function were evaluated in 32 dogs anesthetized with sodium pentobarbital (SP) for surgical preparation, catheterization, extracellular fluid volume expansion and mechanical ventilation. Dogs were randomly distributed in four groups: G control (n = 8), in which dogs remained only under the effect of SP; G ephedrine 2 µg (n = 8); G ephedrine 10 µg (n = 8); and G ephedrine 100 µg (n = 8), in which dogs received 2, 10, and 100 µg.kg-1.min-1 ephedrine, respectively. Cardiovascular and renal parameters were studied at control (M1 and M2), during ephedrine infusion (M3 and M4) and after ephedrine infusion withdrawal (M5). RESULTS: There were no significant differences among groups. There has been a significant increase in heart rate, aortic blood flow, urinary output and fractional sodium excretion in G ephedrine 2 µg. There has been a significant increase in heart rate and filtration fraction in G ephedrine 10 µg while in G ephedrine 100 µg there has been a significant increase in heart rate, mean blood pressure, aortic blood flow, central venous pressure, renal vascular resistance and hematocrit, and a significant decrease in renal plasma and blood flow. CONCLUSIONS: Our study has shown that ephedrine has differentiated dose-dependent hemodynamic and renal effects.

Keywords

ANIMAL, DRUGS, HYPNOTICS, KIDNEY

References

Gamlin F, Vucevic M, Winslow L. The haemodynamic effects of propofol in combination with ephedrine. Anaesthesia. 1996;51:488-491.

Taguchi N, Nishikawa T, Inomata S. Hemodynamic effects of intravenous ephedrine in infants and children anesthetized with halothane and nitrous oxide. Anesth Analg. 1996;82:568-573.

Ralston DH, Shnider SM, Lorimier AA. Effects of equipotent ephedrine, metaraminol, mephentermine, and methoxamine on uterine blood flow in the pregnant ewe. Anesthesiology. 1974;40:354-370.

Carvalho JCA, Cardoso MMSC, Capelli EL. Prophylatic ephedrine during cesarean delivery spinal anesthesia: Dose-response study of bolus and continuous infusion administration. Braz J Anesthesiol Int Issue. 2000;50:32-37.

Hoffman BB, Lefkowitz RJ. Catecholamines, Sympathomimetic Drugs, and Adrenergic Receptor Antagonists. Goodman & Gilman’s The Pharmacological Basis of Therapeutics. 1996:199-248.

Amaral JLG. Suporte Farmacológico da Circulação. O Sistema Cardiovascular e a Anestesia. 1997:125-134.

Omoigui S. The Anesthesia Drug Handbook. 1992:352.

Maxwell HM, Morales P, Crowder CH. Effect of therapeutic doses of ephedrine on renal clearances in normal man. Proc Soc Exp Biol Med. 1951;77:539-542.

Nickel JF, Smyth CMC, Papper EM. A study of the mode of action of the adrenal medullary hormones on sodium, potassium and water excretion in man. J Clin Invest. 1954;33:1687-1699.

Ranges H, Bradley S. Systemic and renal circulatory changes following the administration of adrenin, ephedrine, and paredrinol to normal man. J Clin Invest. 1943;23:687-693.

Zhuang XL, Xu GH, Tong CY. Hemodynamic effects of ephedrine infusion on hypotension during epidural anesthesia in anesthetized dogs. Anesth Analg. 1994;78:S501.

Westman L, Hamberger B, Järnberg PO. Effects of ephedrine on renal function in patients after major vascular surgery. Acta Anaesthesiol Scand. 1988;32:271-277.

Morrison DF. Multivariate Statistical Methods. 1990:495.

Goertz AW, Hübner C, Seefelder C. The effect of ephedrine bolus administration on left ventricular loading and systolic performance during high thoracic epidural anesthesia combined with general anesthesia. Anesth Analg. 1994;78:101-105.

Gilmore JR. Pentobarbital sodium anesthesia in the dog. Am J Physiol. 1965;209:404-408.

Manders WT, Vatner SF. Effects of pentobarbital anesthesia on left ventricular function and distribution of cardiac output in dogs, with particular reference to the mechanism for tachycardia. Circ Res. 1976;39:512-517.

Ramanathan S, Grant GJ. Vasopressor therapy for hypotension due to epidural anesthesia for cesarean section. Acta Anaesthesiol Scand. 1988;32:559-565.

Stoelting RK. Liver and Gastrointestinal Tract. Pharmacology and Physiology in Anesthetic Practice. 1987:780-796.

Nascimento C, Braz JRC, Curi PR. Efeitos da infusão contínua de propofol sobre a função renal do cão: Estudo comparativo com o pentobarbital sódico. Rev Bras Anestesiol. 1994;44:163-170.

Singer I, Epstein M. Potential of dopamine A-1 agonists in the management of acute renal failure. Am J Kid Dis. 1998;31:743-755.

Zarrindast MR. Dopamine-like properties of ephedrine in rat brain. Br J Pharmacol. 1981;74:119-122.

5dd588120e88255042c8fca6 rba Articles
Links & Downloads

Rev. Bras. Anestesiol.

Share this page
Page Sections