Oxigenación tisular y sepsis

[Mitochondrial and microcirculatory distress syndrome in the critical patient. Therapeutic implications]

Mitochondrial and microcirculatory distress syndrome (MMDS) can occur during systemic inflammatory response syndrome (SIRS), and is characterized by cytopathic tissue hypoxia uncorrected by oxygen transport optimization, and associated with an acquired defect in the use of oxygen and energy production in mitochondria, leading to multiple organ dysfunction (MOD). We examine the pathogenesis of MMDS, new diagnostic methods, and recent therapeutic approaches adapted to each of the three phases in the evolution of the syndrome. In the initial phase, the aim is prevention and early reversal of mitochondrial dysfunction. Once the latter is established, the aim is to restore flow of the electron chain, mitochondrial respiration, and to avoid cellular energy collapse. Finally, in the third (resolution) stage, treatment should focus on stimulating mitochondrial biogenesis and the repair or replacement of damaged mitochondria.

Tonometry as a predictor of inadequate splanchnic perfusion in an intra-abdominal hypertension animal model

BACKGROUND

The gastrointestinal system is the most sensitive to the presence of intra-abdominal hypertension. We aimed to assess the early prognostic value of gastric air tonometry as a predictor of inadequate splanchnic perfusion and determine its relation with abdominal perfusion pressure (APP).

METHODS

Twenty-five Large White swine were used for this study. A control group and two study groups were included, in which intra-abdominal pressure (IAP) was elevated with Co2 to 20 and 30 mmHg during 5 h. We measured the intramucosal gastric pH (pHim) and determined gastric luminal PCO2 (PgCO2) and PgCO2gap (gastric luminal CO2-arterial CO2) to evaluate gastric acidity. APP was indirectly obtained through IAP and mean arterial pressure. Additionally, histopathologic samples of small intestine were obtained and analyzed.

RESULTS

pHim showed a decrease in IAP groups, with statistical significance in the 30 mmHg group, 90 min after stabilization period (P < 0.01). Serum lactate showed delayed alteration when compared with pHim, with significant increase, 180 min after stabilization (P < 0.05). The values of PgCO2 and PCO2gap were increased in IAP groups, being statistically significant in the 30 mmHg group, 120 and 150 min, respectively, after stabilization. In increased IAP groups, there was a time progressive decrease of APP, with statistically significant differences observed between groups at 20 min (P < 0.001). The histopathology study revealed parenchymal injury of the intestine at 30 mmHg.

CONCLUSIONS

Tonometry is sensitive to the increase in IAP and relates to the reduction of APP generated by splanchnic hypoperfusion.