Why Water is more important than Urea? And how you can make a difference.

This week Brazil’s capital, Brasília, hosts the World Water Forum, with more than 8,000 participants. Representatives from 172 countries, including political leaders, UNESCO and United Nations members. The theme concerns nature-based solutions to improve fresh water quality and supply. Projections point the by the year 2050, some 5 billion people will be living in areas with poor access to water.
 Ironically, Brasília itself is under scarce water conditions. One day a week, every neighborhood runs out of water, having to remain on theirs water thanks. This works in a rotative-based fashion. Examples pop-up in many world corners, like Bangalore in India and many cities in California. The most shocking situation affects Cape Town, in South Africa. In April, they might come to “day zero”. It means that for 1 day, there will not be even a single drop of water in the city’s entire distribution system.
 Current topics in hemodialysis (HD) are intensive home hemodialysis, Expanded hemodialysis with new membranes and hemodiafiltration with high volumes. Our most basic resource is water. On average, every dialysis session consumes up to 120 liters of ultra-pure water. Each liter of ultra-pure water demands 1.4 liters of filtered water, or 168L/session. How can Nephrology community contribute to the society and mitigate our huge impact in its consumption?
 First, rational choice of amount of dialysate flow (Qd). Many hemodialysis facilities use 600mL/min or even higher as a rule. However, evidence shows that this improves Kt/V in less than 3%, without any clinical outcome improvement. Moreover, increases the water consumption by 20%. Qd around 500mL/min should be set as a limit.

 Second, advocating in favor of Peritoneal Dialysis (PD). Many patients in conservative management of chronic kidney disease are not aware of this treatment as an option for renal replacement therapy. Technology has improved the way doctors and nurses monitor their PD patients. Instead of one appointment every month, telemedicine devices send information instantly to a cloud-based data center. Treatment information is stored and this enables better decision-making process to the nephrologist. On average, a PD treatment consumes 60L/week of solution. Therefore, switching a patient from HD to PD reduces the amount of water used in the treatment.
 Maybe it is time to nephrologists give as much importance to water consumption as they give to urea removal.

From Thiago Reis, MD
Nephrologist
Brasília, Brazil

Picture (from wikipedia): Iguaçú Falls in Brazil, the largest waterfall system in the world .