ABSTRACT
BACKGROUND: The incidence of coagulation of continuous renal replacement therapy circuits remains high. To the best of our knowledge, no scholar has published a protocol to avoid management errors when different types of citrates coexist in the same Intensive Care Unit. AIM: To assess the safety and efficacy of the unification of two protocols with different concentrations of citrate solution. STUDY DESING: A prospective, quasi-experimental study was carried out in the intensive care unit of a tertiary referral hospital (in Barcelona, Spain), over 3 years. Consecutive adult patients requiring continuous renal replacement therapy with citrate were included. The sample was divided into two groups, a control group (concentrated citrate) and an intervention group (diluted citrate). The decision to initiate anticoagulation with diluted (18 mmol/L) or concentrated (136 mmol/L) citrate was made based on the machine available and the decision of the doctor responsible for the patient. It was not possible to randomize the sample. Both protocols were matched with a starting citrate dose of 3.5 mmol/L, and a dialysis solution was used. Post-filter replacement was not used, and the citrate solution was the only fluid administered pre-filter. RESULTS: The analysis included 59 circuits in the concentrated citrate group and 40 circuits in the diluted citrate group. An increased need for electrolyte replacement was observed in the diluted group (p < .001). The concentrated citrate group had a longer filter life (p < .05), and there was a slight trend toward alkalosis. CONCLUSION: The diluted citrate group had a higher incidence of electrolyte replacement. The concentrated citrate group had longer circuit lifespan and a trend toward metabolic alkalosis, although this was not statistically significant. If these conclusions are considered, the protocol can be unified. RELEVANCE TO CLINICAL PRACTICE: The present work aims to provide information on the differences in the use of regional anticoagulation with diluted or concentrated citrate. The objective is to pay special attention to aspects that can lead to complications. The unified protocol proposed in this paper could be extrapolated to any machine on the market that uses either of these two types of citrate concentration.
ABSTRACT
BACKGROUND: During continuous renal replacement therapy (CRRT), circuit coagulation is an important event that can result in suboptimal outcomes. Nurses must remain alert throughout the treatment and observe machine pressures. Transmembrane pressure (TMP) is commonly used for monitoring but it is sometimes too late to return blood to the patient. AIM: To compare the capacity of prefilter pressure (FP) versus TMP to predict the risk of circuit coagulation in adult patients with acute renal failure on CRRT. STUDY DESIGN: An observational, longitudinal, prospective study. This study was carried out in a tertiary referral hospital over 2 years. Data collected included the following variables: TMP, filter or FP, effluent pressure, venous and arterial pressure, filtration fraction, and ultrafiltration constant of each circuit. Means and their trends over time were collected, for both diffusive and convective therapy and for two membrane types. RESULTS: A total of 151 circuits (24 polysulfone and 127 acrylonitrile) were analysed, from 71 patients (n = 22 [34%] women; mean age, 66.5 [36-84] years). Of the total treatments, 80 were diffusive, and the rest were convective or mixed. In the diffusive circuits, a progressive rise in FP was observed without an increase in TMP and with an increasing trend in effluent pressure. Circuit lifespan was between 2 and 90 h. In 11% (n = 17) of the cases, the blood could not be returned to the patient. CONCLUSION: These findings allowed the creation of graphs that indicate the appropriate point to return blood to the patient. FP was a major determinant in this decision; in most cases, TMP was not a reliable parameter. Our findings are applicable to convective, diffusive, and mixed treatments as well as both types of membranes used in this acute setting. RELEVANCE TO CLINICAL PRACTICE: This study provides two clear reference graphs showing risk scales for the assessment of circuit pressures in CRRT. The graphs proposed here can be used to evaluate any machine on the market and the two types of membranes used in this acute setting. Both convective and diffusive circuits can be assessed, allowing safer evaluation in patients who change treatment.
