BACKGROUND:

Hyperchloremia is the most common cause of metabolic acidosis in critically ill patients. The sodium-chloride difference (Na+-Cl-) and chloride/sodium ratio (Cl-/Na+) may simply evaluate the role of hyperchloremia in acid-base disturbances.

OBJECTIVE:

To determine if sodium-chloride difference and chloride/ sodium ratio measured at 24 h of admission are mortality predictors at 30 days in patients with septic shock.

MATERIAL AND METHOD:

A prospective cohort, longitudinal, descriptive and analytic study was done including patients diagnosed with septic shock according to the guidelines of the Surviving Sepsis Campaign in 2012, admitted to the Intensive Care Unit in the period comprising from June 2015 to June 2016.

RESULTS:

The multivariate analysis showed that the Na+-Cl- difference less than 31 mEq/L increases the risk of death in patients with septic shock at 30 days, OR 15.26 (95% CI 1.56-148.49) p=0.019.

CONCLUSION:

The decrease in the Na+-Cl- difference below 31 mEq/L conditioned by hyperchloremia increases the risk of death at 30 days in the patient with septic shock.