Compare amd contrast the working of a kidneys and the artificial dialysis

Based on these data, the blood presented weekly to an average dialysis system in centre-based care in ANZ = 325 ml/minute (i.e. 0.325 L) x 60 minutes x 5 hours x 3 treatments/week = 292.5 litres.

Scroll back for a moment and compare: two normal kidneys receive 10,000 litres of blood/week but a dialyser (the artificial kidney) in ANZ gets a measly 300 litres to play with, if it's lucky.

Yet, while that is clearly a stark difference, the comparison in the US is even starker!

The average calculation for a centre-based patient in the US is: 400 ml/minute (i.e. 0.4 L) x 60 minutes x 3.5 hours x 3 treatments/week = 252 litres; a low volume by ANZ standards, even after (my view) the higher access-damaging pump speeds used in the US have been factored in.

To compare these differences in another way, in ANZ only 292/10,000 = 2.93% of the blood presented in a week to two normal kidneys is presented for dialysis. In the US, it is even less: a paltry 2.52% (= 252/10,000).

What about home-based dialysis?

As a comparison, many home patients, especially in ANZ, perform up to 8-9 hours (mean = 8.5 hours) of overnight, while-asleep dialysis for an average of 5 nights/week. Most who undertake these schedules also run access-friendlier pump speeds of 225-250 ml/minute (mean = 0.2375 L). This provides 0.2375 x 60 x 8.5 x 5 = 605 litres/week for dialysis.

In the US, the most commonly used home profile seems to be a 400 ml/minute x 2 hour/treatment x 6 treatments/week program; this is the one that is most often delivered by the NxStage system, a low-flow system that, by its design, offers less efficient solute clearance compared to the ANZ-preferred single-pass systems. Thus, US home patients under this model present 0.4 L x 60 minutes x 2 hours x 6 treatments/week = 288 litres/week to a less efficient system. While this “short daily” home model clearly presents more blood for dialysis per week than does US centre-based practice, it is still less than the average ANZ centre-based volumes and compares even less favourably with the 600+ litres/week that are presented to the more efficient single-pass systems used by many/most ANZ home dialysis patients.

Explanation:

Hope this helps!