The United Network on Organ Sharing (UNOS) is revising its transplant allocation policy for the second time this year, and critics say the move could favor big cities over rural locations, The Washington Post reports.

The United States faces a severe shortage of donated organs, including livers, kidneys, hearts and lungs. Nearly 115,000 people are on waiting lists across the country, and at least 20 people die every day waiting for a donor.

UNOS, which manages the distribution of livers for transplant across the country, says its new plan will eliminate geographical barriers that had given local transplant centers first dibs on donated organs in their area; instead, the plan will move the system toward a “sickest-first” model that would send livers up to 500 nautical miles away from the donor hospital if the need is deemed an emergency.

Advocates of the new policy say the new rules will help level the playing field for big cities, which face a relentless demand for donated organs and face much longer waiting times. Critics say the new plan will inevitably transfer livers away from rural and low-income parts of the South, Midwest and Northwest to more affluent regions.

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