Aspects in monitoring and treatment of gastrointestinal underperfusion in sepsis. Diagnosis and therapy of gastrointestinal underperfusion in sepsis

Abstract

Tissue hypoxia, especially in the splanchnic area, is still considered to be an important cofactor in the pathogenesis of multiple organ failure. Thus, in the treatment of septic shock the specific effects of ino-tropic drugs on the splanchnic perfusion are of particular interest. To give strict recommendations for monitoring and for therapeutic strategies in the treatment of gastrointestinal failure in patients with sepsis is difficult not only due to the lack of data on clinical outcome and organ dysfunction, but also due to some limitations in the methods applied to assess splanchnic perfusion and oxygenation. A reasonable approach in the management of splanchnic underperfusion in septic patients includes: Measurement of gastric mucosal pH or CO2-gap because it is the only method for the assessment of splanchnic perfusion which can be useful in the clinical routine. Adequate volume loading likely is the most important step in the supportive treatment of patients with septic shock. Unfortunately, what kind of fluids, endpoints, and monitoring techniques should be used is still controversial. Nevertheless, techniques allowing us to achieve and tightly control volume loading and regional perfusion, e.g. the measurement of pHi or CO2-gap, may be helpful. Patients with high DO2 have had better outcome. However, measurement of parameters assessing global and regional oxygenation may be superior than to guide therapy by DO2. To maximize DO2 by the use of very high dosages of catecholamines can be harmful. The recommendation to use dobutamine as catecholamine of first choice seems to be justified. In critically ill patients, no negative effects of norepinephrine on regional perfusion have been demonstrated provided the patient is adequately volume resuscitated and the DO2 is normal or slightly elevated. Therefore, after volume resuscitation and treatment with dobutamine, norepinephrine should be used for achieving an adequate perfusion pressure. Epinephrine and dopamine should be avoided because they seem to restribute blood flow away from the splanchnic region. There are no convincing data yet to support the routine use of low dose dopamine or dopexamine in patients with sepsis. These recommendations are limited by the lack of outcome studies and optimal methods for the assessment of splanchnic perfusion/oxygenation.