Previous Abstract | Next Abstract
Printable Version
A-153
2002
Influence of Norepinephrine and Dopamine on Splanchnic Blood Flow and Oxygen Delivery during Abdominal Surgery: A Randomized, Single-Blind, Comparative Study
Susanne C. Fischer, M.D.; Peter F. Conzen, M.D.; Manfred Nuscheler, M.D.; Rolf Schauer, M.D.; Klaus Peter, M.D.
Ludwig-Maximilians-University, Institute of Anesthesiology, Munich, Germany
Tissue hypoxia, especially in the splanchnic area, is considered an important cofactor in the pathogenesis of multiple organ failure (MOF) in patients undergoing major surgery (1-3). We investigated the effects of two commonly given catecholamines, norepinephrine and dopamine, with respect to intestinal and hepatic blood flows, intestinal oxygen supply, as well as systemic hemodynamic parameters.

Methods:

14 Patients undergoing major abdominal surgery were randomized to receive norepinephrine (0,025-0,3 μg/kg/min) and dopamine (1-10 μg/kg/min) in different sequence. All patients had a thoracic epidural anaesthesia and dosages of norepinephrine (N) and dopamine (D) were adjusted to achieve stable mean arterial pressures (MAP) between 70 and 80 mmHg. Splanchnic and hepatic blood supplies (via the portal vein and the hepatic artery) were assessed by Doppler flow probes. A first set of hemodynamic and blood gas measurements was obtained following exposure of the vessels for perfusion measurement with the first catecholamine (D/N). A second set was obtained after 15 min of stable hemodynamic conditions (MAP) with the second catecholamine (D/N).

Results:

Blood-flow was increased significantly during dopamine from 793 ± 311 (N) to 1337 ± 642 (D) ml/min (p<0,001) in the portal vein, while there was only a slight increase from 225 ± 187 (N) to 262 ± 222 (D) ml/min (p=0,085) in the hepatic artery. Dopamine was also associated with an increase in cardiac output: 7,1 ± 2,1 vs. 9,1 ± 2,3 l/min (p<0,001). This resulted in blood supplies of 11 ± 3,1% and 3,1 ± 2,3% of total cardiac output to portal vein and to hepatic artery during norepinephrine, whereas this fraction increased to 14,7 ± 6,1% (p=0,019) and 3,6 ± 3,0% (p=0,082) during dopamine. Systemic and intestinal oxygen delivery indexes increased significantly from 553 ± 126 (N) to 716 ± 198 (D) ml/min/m2 (p<0,001) and from 61 ± 21 (N) to 105 ± 53 (D) ml/min/m2 (p<0,001), respectively. Oxygen consumption did not change significantly, neither in the systemic vascular bed nor within the gastrointestinal tract (117,1 ± 21 (N) to 116,9 ± 31 (D) ml/min/m2 (p=0,977) and 7,4 ± 3,4 (N) to 6,1 ± 3,0 (D) ml/min/m2 (p=0,137), respectively). The sequence of catecholamine infusion (D followed by N or N followed by D) did not have an impact on the results.

Conclusion:

In patients undergoing abdominal surgery dopamine was associated with a higher fraction of cardiac output supplying the gastrointestinal tract as compared to norepinephrine. Dopamine improved systemic and intestinal oxygen deliveries, whereas oxygen consumption was unaffected. We conclude that this effect may beneficial in protecting the splanchnic bed from hypoxia and hypoxia associated complications.

(1) Landow L et al. Acta Anaesthesiol. Scand. 1994;38: 626-39

(2) Schumacker P et al. Intensive Care Med. 1987;13: 223-229

(3) Boyd O et al. JAMA 1993; 270: 2699-2707

Anesthesiology 2002; 96: A153