We designed this Observational prospective cohort study to assess the safety, effectiveness and efficiency of the introduction of Regional Citrate Anticoagulation (RCA) as election strategy for Continuous Renal Replacement Therapies (CRRT). All patients in need of CRRT without contraindications to the use of RCA were included. It was necessary to adapt and implement the original RCA protocol, for the first time in a Spanish ICU. A total of 90 patients between October 2016 and October 2017 were included. 324 systems were used, 294 (90.74%) were electively removed without any functioning problem. 30 sets (9.25%) had to be removed due to catheter related problems (21, 6.48%) or protocol violation (9, 2.77%). Median filter lifespan was 60.45 hours. System stability and ionic calcium levels were easily achieved in 93.51% of patients. No significant side effects or complications associated with the use of RCA were observed. This method, compared to the use of heparin in the past in our unit (alone or in combination with epoprostenol) turned out to be more efficient. We concluded that, in our experience, the use of RCA is safe, predictable, effective and efficient in critical patients undergoing CRRT.