[Circulatory function and oxygenation during hemihepatectomy. Dopamine versus dopexamine].

Area of Science:

• Anesthesiology and Critical Care Medicine
• Hepatobiliary Surgery
• Pharmacology

Background:

• Liver surgery, particularly hemihepatectomy with hilar occlusion, presents challenges in maintaining hepatic oxygenation.
• Dopamine and dopexamine are vasoactive agents used to support cardiocirculatory function and oxygen delivery during major surgeries.

Purpose of the Study:

• To compare the effects of low-dose dopamine versus dopexamine on liver-venous oxygen saturation, oxygen delivery and demand, liver function, and cardiocirculatory parameters.
• To evaluate these agents during the reperfusion period following liver hilus occlusion in hemihepatectomy.

Main Methods:

• A randomized, double-blind study involving 20 patients undergoing hemihepatectomy.
• Patients received either dopamine (2 µg/kg/min) or dopexamine (0.5 µg/kg/min) perioperatively.
• Hemodynamic parameters were monitored using pulmonary artery and liver venous catheters, with blood samples analyzed at four time points.

Main Results:

• Significant differences were observed in cardiac index and systemic oxygen delivery 5 minutes after liver hilus reperfusion.
• Pulmonary shunt volume increased more in the dopexamine group by the end of the operation.
• No significant differences were found between the groups regarding liver venous oxygen saturation or liver function tests.

Conclusions:

• Dopexamine cannot be considered superior to dopamine in liver surgery involving hilar occlusion.
• Further research is needed to elucidate the specific influence of dopamine on the hepatic-splanchnic region during such procedures.