1. Comparison of Dopamine and Norepinephrinein the Treatment of Shock ALLAN PEPE VASQUEZ TEJADA Medico Residente de Cirugía. HVLE
2. El control de la presión tiene dos regulaciones Regulación rápida Barorreceptores de alta presión y de baja presión Regulacion de largo plazo
3. El centro de la presión arterial se encuentra en el bulbo raquídeo rostral ventrolateral y se conecta con la columna intermedio lateral de la medula espinal y con el vago. La noradrenalina, la adrenalina y dopamina son vasopresoresendogenos que tiene diferente forma de acción
7. DOPAMINA La dopamina (3,4-dihidroxifeniletilamina) produce vasodilatación renal Causan estimulación del miocardio Estimulan la frecuencia cardíaca y la vasoconstricción periférica
8. Actualmente la dopamina no está recomendada a dosis bajas Estas acciones determinan un incremento en el consumo de oxígeno miocárdico debido a un aumento en la frecuencia cardíaca y en la vasoconstricción coronaria En pacientes con miocardio agudamente isquémico, la dopamina puede inducir arritmias y precipitar angina.
9. NORADRENALINA Es un agonista potente de los receptores –adrenérgicos El gasto cardíaco persiste sin cambios o está disminuido Aumenta en grado importante el flujo coronario Recomendada la infusión de norepinefrina en choque donde no se logra una estabilidad con la dopamina
10. "La dopamina es el fármaco de elección para el shock" (Vincent 1999).“ se indica para revertir la hipotensión hemodinámicamente significativa debida a infarto miocárdico, traumatismo, sepsis, insuficiencia cardíaca manifiesta, insuficiencia renal, insuficiencia cardíaca congestiva crónica..." (Levy 1992). "La norepinefrina parece ser sumamente útil en el tratamiento del shock causado por disminución inapropiada en la resistencia vascular periférica como el shock séptico y el neurogénico"
11. "La epinefrina se indica principalmente para los estados de gasto cardíaco bajo" (Sladen 1999) y se recomienda como "el tratamiento de primera línea en pacientes con shock anafiláctico" (Breithaupt 2000; Vincent 1999). "La dobutamina es muy eficaz en pacientes con miocardiopatía e insuficiencia cardíaca congestiva" (Sladen 1999).
12. Tres estudios compararon norepinefrina con dopamina (Marik 1994; Martin 1993; Ruokonen 1993): 16 pacientes de 31 murieron en el grupo de norepinefrina en comparación con 19 de 31 en el grupo de dopamina (RR 0,88; 0,57 a 1,36) (ver comparación 02, el resultado 01).
14. Theadministration of fluids, which is the first-line therapeutic strategy, is often insufficient to stabilize the patient’s condition, and adrenergic agents are frequently required to correct hypotension.
15. Dopamineand norepinephrine influence alpha-adrenergic and beta-adrenergic receptors, but to different degrees Dopamine and norepinephrine may have different effects on the kidney, the splanchnic region, and the pituitary axis, but the clinical implications of these differences are still uncertain.
17. Thepatientwasconsideredto be in shock if the PAM was less than 70 mm Hg or the PAS was less than 100 mm Hg o there was an elevation in the central venous pressure to >12 mm Hg and if there were signs of tissue hypoperfusion
18. Patientswere excluded if had already received a vasopressoragentfor more than 4 hours during the current episode of shock had a serious arrhythmia had been declaredbrain-dead.
19. The study period lasted a maximum of 28 days The primary end point of the trial was the rate of deathat 28 days
20. A total of 1679 patients were enrolled — 858 in the dopamine group and 821 in the norepinephinegroup. Therewere no significantdifferences between the two groups withregardto most of the baseline characteristics
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23. The type of shock that was seen most frequently was septic shock (in 1044 patients ), followed by cardiogenic shock (in 280 patients) and hypovolemicshock (in 263 patients). Hydrocortisone was administered in 344 patients who received dopamine (40.1%) and in 326 patients who received norepinephrine(39.7%)
24. There were no major between-group differences in the total amounts of fluid given, although patients in the dopamine group received more fluids on day 1 Urine output was significantly higher during the first 24 hours in the dopamine group than among those in the norepinephrine group, but this difference eventually disappeared, so that the fluid balance was quite similar between the twogroups.
25. Therewere no significantdifferences in the causes of death between the two groups, although death from refractory shock occurred more frequently in the group of patients treated with dopamine than in the group treated with norepinephrine (P = 0.05)
26. More patients had an arrhythmia, especially atrial fibrillation, in the dopamine group than in the norepinephrinegroup The rate of death at 28 days was significantly higher among patients with cardiogenic shock who were treated with dopamine than among those with cardiogenic shock who were treated with norepinephrine (P = 0.03)
27. The rate of death at 28 days was significantly higher among patients with cardiogenic shock who were treated with dopamine than among those with cardiogenic shock who were treated with norepinephrine (P = 0.03)
31. The rate of death did not differ significantly between the group of patients treated with dopamine and the group treated with norepinephrine Dopamine was associated with more arrhythmic events than was norepinephrine Dopaminewasassociatedwith a significant increase in the rate of death in the predefined subgroup of patients with cardiogenicshock.
