Effect of perfusion pressure on the splanchnic circulation after CPB: a pilot study

Abstract

Background: The impact of different blood pressure targets is unknown for post cardiac surgery patient in the intensive care unit. We, therefore, investigated the effects of a mean arterial pressure (MAP) target of 65 or 85 mmHg on splanchnic oxygenation, metabolic function, cytokine regulation and gastric tonometry after cardiopulmonary bypass.

Methods: Sixteen patients were randomized to the HLH group (high-low-high) where MAP of 85-65-85 mmHg was targeted or the LHL group where MAP 65-85-65 mmHg was targeted with norepinephrine infusion.

Results: MAP targets were achieved in all patients at all timepoints (64 ± 3, 84 ± 4; 65 ± 5, LHL group; vs. 84 ± 3; 66 ± 2; 85 ± 5 mmHg, HLH group). At corresponding timepoints, hepatic venous saturation was 41 ± 15%; 58 ± 24%; 56 ± 21% in the LHL group vs. 50 ± 19%; 43 ± 20%; 41 ± 18% in the HLH group (P<0.05). No changes were observed in cardiac output, global or trans-splanchnic lactate levels and cytokine levels or in gastric tonometry CO2.

Conclusion: Achieving a MAP target of 85 mmHg by means of norepinephrine infusion after CPB appears safe for the splanchnic circulation.