Introduction: Part of the interventions in patients admitted to intensive care units (ICU) consist of the administration of crystalloids, implying a risk for the development of side effects. One of these is hyperchloremia, linked to the appearance of metabolic acidemia and systemic inflammatory response. Given these findings, observational studies have been developed, trying to establish an association between hyperchloremia and outcomes such as mortality and kidney failure; however, its diverse results prompt the development of new studies. In Colombia, there are no prospective cohort studies that establish any type of association with hard outcomes. Goal. To determine the association between the development of hyperchloremia and mortality and acute renal failure, in patients hospitalized in the ICU, in two hospitals in Bogotá D.C. Methodology: Analytical prospective cohort study conducted between June 1, 2019 and August 31, 2021. Results: 325 patients were analyzed, the cumulative incidence of hyperchloremia and acute renal failure in the entire study population was 44.6% and 29.5%, respectively. The cumulative incidence of death in the exposed was 36.5% vs 23.3% in the unexposed, with a relative risk RR=1.57, (95% CI 1.11-2.2) (p=<0.001). The cumulative incidence of acute renal failure was 43.4% in exposed patients and 18.3% in non-exposed patients, with a RR=2.37 with a (95% CI 1.65-3.4) (p<0.001). Conclusion: There is an association between the development of hyperchloremia and the outcomes of mortality and acute renal failure in critically ill patients.