What are the principles of green nephrology in kidney disease management?

Green Nephrology Principles

Green nephrology is a comprehensive framework aimed at reducing the environmental footprint of kidney care through three interconnected approaches: technical optimization of dialysis procedures, clinical pathway improvements across all CKD stages, and societal integration of sustainable practices—all while maintaining or improving patient outcomes. 1

Core Conceptual Framework

Green nephrology encompasses three distinct but complementary approaches that must be understood to implement sustainable kidney care effectively 1:

• Technical approach: Focuses primarily on reducing the carbon footprint of dialysis through water conservation, energy efficiency, and waste reduction 1, 2
• Clinical approach: Encompasses both medical and non-medical treatments across all phases of CKD, emphasizing prevention, delayed dialysis initiation, and lifestyle interventions 1, 3
• Comprehensive approach: Embeds kidney care within broader societal sustainability goals, aligning with UN climate principles and global health initiatives 4

The GREEN-K Initiative

The global nephrology community has launched "GREEN-K" (Global Environmental Evolution in Nephrology and Kidney Care) with the vision of "sustainable kidney care for a healthy planet and healthy kidneys" 4:

• Mission: Promote and support environmentally sustainable and resilient kidney care globally through advocacy, education, and collaboration 4
• Patient-centric approach: Permits both climate change mitigation and adaptation while maintaining quality care 4
• Multi-stakeholder focus areas: Education, sustainable clinical care, environmentally sustainable innovations, procurement, and infrastructure 4

Reducing Dialysis Burden: The Intent-to-Delay Strategy

The single most impactful intervention is reducing the overall burden of dialysis by delaying initiation whenever clinically appropriate, as dialysis produces approximately 2 kg of potentially contaminated waste per session plus an equal weight of potentially recyclable materials. 3

Specific strategies include:

• Incremental dialysis schedules: Start with once or twice weekly dialysis in patients with residual kidney function rather than immediately implementing thrice-weekly schedules 3
• Conservative kidney management: Offer comprehensive conservative management programs as an alternative to dialysis for appropriate patients, supported by symptom management, psychological care, and advance care planning 5
• Optimized clinical pathways: Implement early CKD identification and intervention to slow progression, reducing the number of patients reaching dialysis 5

Technical Dialysis Optimization

Water Conservation Strategies

Hemodialysis facilities waste up to 60% of treated water, making water conservation a critical priority 2:

• Water recycling systems: Implement technologies that recycle and reuse dialysate water 2
• Reduced dialysate flow rates: Lower flow rates from standard 500-800 mL/min to optimized levels without compromising dialysis adequacy 2
• Sorbent-based systems: Adopt sorbent dialysis technology that regenerates dialysate, dramatically reducing water consumption 2

Energy Reduction Approaches

• Renewable energy integration: Install solar panels or purchase renewable energy credits for dialysis facilities 2
• Advanced hemodialysis machine designs: Select equipment with energy-efficient features and include environmental-impact criteria in procurement checklists 2, 3
• Home dialysis promotion: Encourage home hemodialysis and peritoneal dialysis, which have lower facility-based energy demands 2

Waste Management Hierarchy

Implement well-planned triage of contaminated versus non-contaminated materials, as most dialysis waste is incorrectly classified as hazardous when it could be recycled. 3

• Contaminated waste reduction: Limit biohazardous waste designation to truly contaminated items (bloodlines, dialyzers in contact with blood) 3
• Plastic recycling: Establish protocols for recycling non-contaminated plastic packaging, which represents approximately 50% of dialysis waste by weight 3
• Paper and glass recycling: Implement separate collection streams for recyclable paper and glass materials 3
• Reuse of household hospital materials: Encourage reuse of items like towels, gowns, and non-medical supplies 3

Clinical Pathway Optimization

Prevention and Early Intervention

Choose treatment regimens that prevent disease progression, as complete clinical remission may not be possible in all forms of chronic glomerulonephritis, but prolonged or multiple rounds of immunosuppression may be required to prevent or delay CKD progression. 5

• Proteinuria reduction: Target proteinuria as a surrogate endpoint, as reducing protein excretion slows progression and delays dialysis need 5
• SGLT2 inhibitors: Initiate when eGFR ≥20 mL/min/1.73 m² and continue until dialysis or transplant, as these medications slow progression and reduce the number of patients reaching dialysis 6, 7
• RAS inhibition: Titrate ACE inhibitors or ARBs to maximum tolerated doses for patients with hypertension or albuminuria 6, 7

Lifestyle and Non-Pharmacological Interventions

Limit drugs and favor "natural" medicine focusing on lifestyle and diet, as these interventions reduce both medication waste and the environmental impact of pharmaceutical production. 3

• Dietary modifications: Prescribe plant-based, Mediterranean-style diets with protein restriction to 0.8 g/kg/day for non-dialysis CKD patients and sodium restriction to <2,300 mg/day 6, 7
• Physical activity: Implement structured exercise programs of 150 minutes weekly of moderate-intensity activity 7
• Smoking cessation: Mandate smoking cessation programs, as smoking accelerates CKD progression 6

Infrastructure and Procurement

Planet-Friendly Facility Design

Demand planet-friendly approaches in the building of new facilities, incorporating environmental sustainability from the design phase. 3

• Energy-efficient HVAC systems: Install heating, ventilation, and air conditioning systems optimized for dialysis facility requirements 3
• Water treatment optimization: Design water treatment systems that minimize waste water production 3
• Sustainable building materials: Use recycled, recyclable, or sustainably sourced construction materials 3

Procurement Criteria

Introduce environmental-impact criteria in checklists for evaluating dialysis machines and supplies, making sustainability a standard procurement consideration alongside clinical efficacy and cost. 3

• Lifecycle assessment: Demand data on the complete lifecycle of dialysis equipment, including manufacturing, transportation, use, and disposal 1
• Pharmaceutical environmental impact: Acknowledge the lack of data on drug lifecycle and advocate for pharmaceutical companies to provide environmental impact assessments 1
• Supplier sustainability requirements: Prioritize vendors with documented environmental sustainability programs 3

Education and Implementation

Multi-Level Educational Programs

Greater awareness of nephrology's environmental impact is needed to promote education and research 1:

• Medical school integration: Implement educational games and curricula on green nephrology principles for medical students 1
• Continuing medical education: Incorporate sustainability topics into nephrology conferences and meetings, including healthy eating demonstrations and reduction of plastic and paper waste at events 1
• Daily clinical practice: Teach through example by personalizing dialysis schedules and adapting treatments to each patient's needs rather than standardized protocols 1

Overcoming Implementation Barriers

Several barriers exist that educational approaches can help overcome 1:

• Lack of original data: Promote research on environmental impact of specific nephrology interventions and publish findings 1
• Knowledge gaps: Address the absence of lifecycle data for commonly used drugs and procedures through advocacy and research 1
• Resistance to change: Use educational programs to demonstrate that sustainable practices can maintain or improve patient outcomes while reducing environmental harm 1

Avoiding Futility in Clinical Work and Research

Avoid futility in clinical work and research by carefully selecting patients for aggressive interventions and ensuring research protocols minimize unnecessary resource consumption. 1

• Shared decision-making: Implement advance care planning for all CKD patients to ensure treatments align with patient values and avoid unwanted interventions 5
• Conservative management protocols: Develop comprehensive programs including symptom management, psychological care, spiritual care, and culturally sensitive end-of-life care as alternatives to dialysis for appropriate patients 5
• Research efficiency: Design clinical trials that minimize waste, avoid unnecessary testing, and prioritize patient-centered outcomes 1

Critical Pitfalls to Avoid

• Treating sustainability as optional: Environmental sustainability must be integrated into core nephrology practice, not treated as an add-on or luxury 4
• Focusing only on dialysis: While dialysis has the highest environmental impact, green nephrology must address all phases of CKD care, from prevention through transplantation 1
• Ignoring patient outcomes: Sustainable practices must maintain or improve patient outcomes; environmental goals cannot compromise quality of care 4
• Lack of measurement: Without tracking water use, energy consumption, and waste generation, facilities cannot identify improvement opportunities or measure progress 2
• Inadequate waste segregation: Failing to properly separate contaminated from non-contaminated waste results in unnecessary hazardous waste disposal costs and environmental harm 3