Systemic and microcirculatory effects of dobutamine in patients with septic shock.
OBJECTIVE
The aim of this study was to characterize the cardiovascular responses to dobutamine and their predictors. Our hypotheses were that dobutamine mainly produces tachycardia and vasodilation and fails to improve the microcirculation of patients with septic shock.


METHODS
Systemic hemodynamics and sublingual microcirculation were evaluated with dobutamine (0, 2.5, 5.0, and 10.0 μg kg(-1) min(-1)) in 23 patients with septic shock.


RESULTS
Dobutamine increased heart rate, cardiac index, and stroke volume index (SVI). Mean blood pressure was unchanged, and systemic vascular resistance decreased. Individual responses were heterogeneous. Stroke volume index increased in 52% of the patients. These patients showed lower changes in mean blood pressure (3 ± 16 mm Hg vs -10 ± 6 mm Hg, P < .05) and higher increases in cardiac index (1.47 ± 0.93 L m(-1) m(-2) vs 0.20 ± 0.5 L m(-1) m(-2)) than did nonresponders. Changes in SVI significantly correlated with echocardiographic left ventricular ejection fraction (r = 0.55). In the whole group, perfused capillary density remained unchanged (14.0 ± 4.3 mm/mm(2) vs 14.8 ± 3.7 mm/mm(2)), but improved if basal values were 12 mm/mm(2) or less (9.1 ± 4.3 mm/mm(2) vs 12.5 ± 4.8 mm/mm(2)).


CONCLUSIONS
Dobutamine produced variable hemodynamic effects. Systolic dysfunction was the only variable associated with increases in SVI. Finally, dobutamine only improved sublingual microcirculation when severe alterations were found at baseline.
Servicio de Terapia Intensiva, Sanatorio Otamendi y Miroli, Buenos Aires, Argentina.
Carolina
C
Enrico
Vanina S
VS
Kanoore Edul
Alejandro Risso
AR
Vazquez
María C
MC
Pein
Ricardo A
RA
Pérez de la Hoz
Can
C
Ince
Arnaldo
A
Dubin
D000136:Acid-Base Equilibrium / Q000187:drug effects; D000368:Aged; D000369:Aged, 80 and over; D001794:Blood Pressure / Q000187:drug effects; D002302:Cardiac Output / Q000187:drug effects; D002316:Cardiotonic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D004280:Dobutamine / Q000494:pharmacology / Q000627:therapeutic use*; D005260:Female; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D019344:Lactic Acid / Q000378:metabolism; D008297:Male; D008833:Microcirculation / Q000187:drug effects*; D008875:Middle Aged; D009060:Mouth Floor / Q000098:blood supply*; D012772:Shock, Septic / Q000188:drug therapy*
D002316:Cardiotonic Agents; D019344:Lactic Acid; D004280:Dobutamine