Precise individualized dialysate temperature regulation for the prevention of intradialytic hypotension and the protection of cerebral blood perfusion in elderly patients on maintenance hemodialysis

ObjectiveTo investigate the effects of individualized dialysate temperature settings on the incidence of intradialytic hypotension and cerebral blood perfusion in elderly patients receiving maintenance hemodialysis （MHD）， and to provide clinical evidence for optimizing individualized dialysis parameters in this population.MethodsThis single-center retrospective study included 260 elderly MHD patients admitted to Beijing Friendship Hospital， Capital Medical University， from March 2022 to March 2025. According to the temperature adjusted during dialysis， patients were divided into four groups. Group A included 64 patients with ［（T＋0.5） ℃］， with the dialysate temperature set 0.5 ℃ higher than the measured temperature ［（37.3±0.6） ℃］； Group B included 66 patients with the temperature set at 37 ℃， the default standard dialysate temperature of the dialysis machine （37.0 ℃）； Group C included 67 patients with T equal to the measured temperature ［（36.6±0.5） ℃］； and Group D included 63 patients with ［（T‒0.5） ℃］， with the dialysate temperature set 0.5 ℃ lower than the measured temperature ［（36.1±0.4） ℃］. Heart rate and mean arterial pressure were compared among the four groups at T0 （before dialysis）， T1 （2 h after dialysis）， T2 （6 h after dialysis）， and T3 （24 h after dialysis）. In addition， the National Institutes of Health Stroke Scale （NIHSS） score， Barthel index （BI） score， comfort score， cerebral blood flow （CBF）， time-to-peak （rTTP）， and cerebral blood volume （CBV） were compared before and after dialysis. Adverse events during dialysis and the incidence of hypotension were also recorded.ResultsIn all four groups， heart rate at T1， T2， and T3 was higher than at T0， whereas mean arterial pressure at T1， T2， and T3 was lower than at T0 （P<0.05）. In Group D， heart rate at T1， T2， and T3 was （79.85±3.86）， （81.87±3.65）， and （80.87±4.45） beats/min， respectively， which was lower than that in the other three groups， while mean arterial pressure was （88.61±4.49）， （87.88±4.75）， and （88.54±4.13） mmHg （1 mmHg=0.133 kPa）， respectively， which was higher than that in the other three groups （P<0.05）. At 12 h after dialysis， there was no statistically significant difference in NIHSS scores among the four groups （P>0.05）. The comfort score in Group D was （2.02±0.79）， and the BI score was better than those in the other groups （P<0.05）. At 4 h after dialysis， CBV， CBF， and rTTP in all groups were lower than those before dialysis； however， in Group D， CBV was （3.23±0.19） mL/100 g， CBF was （50.54±6.88） mL·（100 g）-1·min-1， and rTTP was （6.19±1.67） s， all of which were higher than those in the other three groups （P<0.05）. There was no statistically significant difference in the incidence of adverse events among the four groups （P>0.05）. The incidence of hypotension was 14.06% in Group A， 9.09% in Group B， 4.48% in Group C， and 1.59% in Group D （P=0.035）.ConclusionAn individualized low-temperature dialysate setting based on reducing the measured oral temperature by 0.5 ℃ can effectively reduce the risk of intradialytic hypotension in elderly MHD patients， stabilize hemodynamic status， improve cerebral blood perfusion， and enhance patient comfort and activities of daily living without increasing the risk of adverse events. This approach provides a safe and feasible clinical strategy for optimizing dialysis parameters in elderly MHD patients.