Effect of different modalities of sustained low-efficiency dialysis on Intradialytic hypotension in intensive care unit patients with acute kidney injury

Abstract

The hemodynamic state is a critical factor for dialysis efficiency in acute kidney injury (AKI) patients. Currently, most of the AKI patients requiring renal replacement therapy (RRT) are critically ill and hemodynamically unstable. The RRT modalities preferentially used in this setting are continuous renal replacement therapies (CRRTs), such as hemofiltration and hemodiafiltration, or sustained low-efficiency dialysis (SLED). Although SLED and CRRT have showed similar efficacy in AKI, SLED is less expensive and technically easier to perform. Hypotension is a usual and feared event during RRT in critically ill AKI patients, making its treatment difficult. In addition, intradialytic hypotension may precipitates ischemic injury and delays the recovery in AKI. Intradialytic hypotension is related to factors that are procedure dependent (volume and rate of ultrafiltration, changes in plasma osmolality, composition and temperature of dialysate) and patient dependent (hypovolemia, cardiac dysfunction, autonomic dysfunction, and vasodilatation). Efficient treatment of IDH is still a great challenge to the nephrologists, there are no generally accepted guidelines. Adequate therapy is difficult and requires a multilevel strategy. This study included 10 randomly selected ICU patients with AKI requiring RRT and the same patient was subjected to three subsequent modalities of SLED, each session was 8 hours duration. • Modality 1: SLED therapy with dialysate temperature of 37°C, fixed UF rate and fixed dialysate sodium concentration of 138 mEq/L. • Modality 2: SLED therapy with Low dialysate temperature of 35.5°C, fixed UF rate and fixed dialysate sodium concentration on f 138 mEq/L. • Modality 3: SLED therapy with dialysate temperature of 37°C, Sodium and Ultra filtration profiles. The sodium profile had an initial sodium concentration of 150 mEq/L and a final concentration of 138 mEq/L, with a linear decrease in sodium concentration. The Ultra filtration profile had a linear decrease in the UF rate, starting at 25% above the average UF rate. It was found that there was statistical significant difference between the three modules in number of hypotensive episodes with reduction of hypotensive episodes with Sodium profiling and ultra filtration profiling(3rd module) & low dialysate temperature (2nd module) but the best with 3rd module . It was found that there was statistical significant difference in the degree of change of the systolic blood pressure pre and post dialysis between the three modules as the systolic blood pressure decreased by an average of (13%, 8% and 5%) in each module respectively showing that the postdialysis systolic blood pressure was best preserved in the 3rd module. It was found that there was no statistical significant difference in the degree of change of MAP (pre and post dialysis) between the three modules but the least change was with the 3rd module as MAP decreased by an average of (10%, 8% and 6%) in each module respectively. It was found that there was no statistical significant difference in the the degree of change of serum Na (pre and post dialysis) between the three modules although that the serum Na decreased in the 1st and 2nd modules respectively and increased in the 3rd module. It was found that there was no statistical significant difference in the degree of change of the Urea Reduction Ratio as it was similar in all modules and Urea Reduction Ratio decreased by an average of (33%, 32%, and 34%) in each module respectively. In conclusion, The present study found that the use of Sodium profiling and ultra filtration profiling & low dialysate temperature techniques with SLED sessions was associated with significantly less intradialytic hypotensive episodes and best preservation of blood pressure and an efficient approach for prevention of intradialytic hypotension in intensive care unit patients with acute kidney injury but the best results were with the Sodium profiling and ultra filtration profiling technique.