Positive Fluid Balance Linked to Acute Kidney Injury and Mortality in Sepsis Patients

A recent retrospective study chart review shed light on the association between fluid balance, acute kidney injury (AKI), and mortality in sepsis and septic shock patients  The study made a striking discovery that in patients battling sepsis and septic shock, a more positive fluid balance correlates with a heightened risk of acute kidney injury (AKI) and, alarmingly, a higher mortality rate. 

The study results were published in the Journal of Critical Care. 

Sepsis and septic shock are life-threatening conditions that require prompt and effective treatment. Among the critical aspects of sepsis management is fluid resuscitation to maintain hemodynamic stability. However, there has been a growing debate over the optimal approach to fluid management in these patients. Hence Belgium researchers conducted a retrospective chart review to explore the association between fluid balance, acute kidney injury (AKI), and mortality in sepsis and septic shock patients. 

The study conducted a retrospective chart review involving 482 patients who received treatment for sepsis or septic shock. Patients were categorized into quartiles based on their cumulative fluid balance on both day 1 and day 3 of their intensive care unit (ICU) admission. Logistic regression models were employed to investigate the relationship between fluid balance, the incidence of AKI, and ICU mortality.

Findings of the study: 

• The analysis revealed intriguing findings.
• Initially, there were no discernible differences in fluid input between survivors and non-survivors during the early days of ICU admission.
• However, a significant distinction emerged in fluid output, leading to a more positive fluid balance in non-survivors on both day 1 and day 3. 
• The logistic regression model identified that a positive fluid balance on day three of ICU admission was independently linked to a greater risk of ICU mortality, with an odds ratio of 1.007 for every one ml/kg (P = 0.0038). 
• Positive fluid balance was also associated with a heightened risk of reaching AKIN stage III, with an odds ratio of 1.006 for every one ml/kg (p = 0.031).

These findings underscore the critical importance of careful fluid management in sepsis and septic shock patients. While fluid resuscitation is a cornerstone of treatment, excessive or unbalanced fluid administration can have detrimental consequences. There is a high necessity for a nuanced and individualized approach to fluid therapy in sepsis patients, considering the potential risks associated with positive fluid balance.

Further reading: The association between increasing fluid balance, acute kidney injury and mortality in patients with sepsis and septic shock: A retrospective single center audit. doi:https://doi.org/10.1016/j.jcrc.2023.154367