Impact of Dialysis Modality

Impact of Dialysis Modality on the Occurrence of Peridialytic Critical Limb Ischemia in Chronic Hemodialysis Patients

• Peripheral Arterial Disease (PAD) is a common condition in patients with End-Stage Renal Failure (ESRF) undergoing dialysis.
• Late diagnosis of PAD and hypoperfusion induced by dialysis sessions explain the high morbidity and mortality associated with this condition in hemodialysis patients compared to the general population.
• The main objective of this study is to evaluate whether a dialysis modality (conventional 4-hour sessions 3 times per week or daily 2-hour sessions 6 times per week) is more effective in preventing the progression of critical limb ischemia during dialysis and thus preventing serious complications of PAD.

This study will help define a population of chronic hemodialysis patients at risk of developing critical limb ischemia during dialysis sessions. This will allow us to offer them the dialysis modality that best maintains distal perfusion of the lower limbs and may prevent the onset of trophic disorders.

• The hypothesis of this project is that daily hemodialysis would provide better stability of distal lower limb perfusion compared to 4-hour intermittent hemodialysis: because ultrafiltration is short and daily, vascular filling from the interstitial space to the plasma space is optimized, reducing the risk of sudden hypovolemia, which is detrimental to microcirculation. Furthermore, the improved hemodynamic tolerance of ultrafiltration results in less of a drop in blood pressure, which can lead to distal hypoperfusion.
• To validate this hypothesis, this study measured the systolic blood pressure at the great toe (SBP) by photoplethysmography several times during a 4-hour dialysis session and then several times during a 2-hour daily dialysis session. This technique allows for the detection of critical limb ischemia in dialysis patients with good sensitivity. The judgment criterion will be the transition to critical ischemia defined by a PSGO of less than 30 mmHg or less than 50 mmHg in the presence of trophic disorders.

This study should enable the recommendation of switching to daily hemodialysis for patients at risk of developing critical limb ischemia on conventional 4-hour intermittent hemodialysis. The objective is to prevent the onset of trophic disorders, the consequences of which in terms of morbidity and mortality are dramatic.

Inclusion Criteria:

• Patient must be an adult (aged 18 years or older)
• Must have been on chronic hemodialysis for at least 3 months
• Must be willing to undergo one week of daily hemodialysis to assess its clinical benefit
• Must have read and understood the information letter and agree to participate in the study

Exclusion Criteria:

• Bilateral amputation including the big toes
• Hemodynamic instability defined by a peridialytic blood pressure drop of more than 50% of sessions
• Patient undergoing acute hemodialysis
• Contraindication to either of the two dialysis modalities
• Patient not wishing to undergo daily hemodialysis