Monitoring Peripheral Perfusion in Sepsis associated Acute Kidney Injury: Analysis of Mortality

Microcirculatory disorders have been consistently
linked to the pathophysiology of sepsis. One of the major organs affected is
the kidneys, resulting in sepsis-associated acute kidney injury (SA-AKI) that
correlates considerably with mortality. However, the potential role of clinical
assessment of peripheral perfusion as a possible tool for SA-AKI management has
not been established. To address this gap, the purpose of this study was to
investigate the prevalence of peripheral hypoperfusion in SA-AKI, its association
with mortality, and fluid balance.
This observational cohort study enrolled consecutive septic patients in the Intensive Care Unit. After fluid
resuscitation, peripheral perfusion was evaluated using the capillary filling
time (CRT) and peripheral perfusion index (PI) techniques. One hundred and forty-one
patients were included, 28 (19%) in the non-SA-AKI group,
and 113 (81%) in the SA-AKI group. The study
revealed higher peripheral hypoperfusion rates in the SA-AKI group using the CRT (OR 3.6; 95% CI 1.35-9.55; p < 0.05). However, this result lost significance after
multivariate adjustment. Perfusion abnormalities in the SA-AKI group diagnosed
by both CRT and PI methods were associated to higher rates of 28-day
mortality (p < 0.01). The PI's temporal analysis showed a high predictive
value for death over the first 72 h (p < 0.01). A weak correlation between
PI values and the fluid balance was found over the first 24 h (r = - 0.20; p <
0.05). In conclusion, peripheral perfusion
was not different intrinsically between patients with or without SA-AKI. The presence of
peripheral hypoperfusion in the SA-AKI group has appeared to be a prognostic
marker for mortality. This evaluation maintained its predictive value over the
first 72 hours. The fluid balance possibly negatively influences peripheral
perfusion in the SA-AKI.