During the three years that HBO's “Last Week Tonight” has aired, host John Oliver has skewered one political absurdity after another.

But the late-night comedian has also used his platform to delve into more complicated issues — the debate over net neutrality, for example — often with comical and significant results.

On Sunday, Oliver once again turned his attention to a topic that he admitted would risk prompting viewers to “push the button on your TV remote marked 'Dear God Literally Anything Else.'”

Kidney dialysis.

Oliver explained dialysis as a process in which a person is hooked up to a machine that removes blood out of the body, cleans it, then returns it to circulation. “Think of it as a Brita pitcher for your blood,” he said.

And he urged people to learn about the for-profit dialysis industry, however boring it may seem, because an increasing number of people in the United States suffer from kidney disease and rely on the “exhausting process” of dialysis to stay alive.

Kidney disease is the ninth leading cause of death in the United States, according to the Centers for Disease Control and Prevention. Oliver also cited a 2010 ProPublica investigation that revealed the United States “continues to have one of the industrialized world's highest mortality rates for dialysis care” despite spending more on it than other nations, by some accounts.

“So we're spending the most to essentially get the least,” Oliver said. “We're basically paying for a fully loaded Lamborghini and receiving a drunk donkey on roller skates.”

Oliver recounted the history of how the country's for-profit dialysis industry came to be — the result, he said, of good intentions mixed with “bad incentives, poor oversight and profiteering.”

In 1972, President Richard Nixon signed a bill into law saying the government would pay for dialysis for anyone who needed it.

“Essentially we have universal health care in this country, for one organ in your body,” Oliver said. “It's like your kidneys, and only your kidneys, are Canadian.”

At the time, only about 10,000 patients needed coverage, but over the past four decades, the rise of diabetes and high blood pressure has led to nearly half a million people requiring dialysis, Oliver said. The cost of covering dialysis now accounts for 1 percent of the federal budget, he added.

As a result, a network of outpatient dialysis clinics sprung up around the country to accommodate these patients' needs. Two large companies own 70 percent of these clinics, Oliver noted: Fresenius Medical Care and DaVita.

Despite “significant issues with both of them,” Oliver said he would focus on DaVita, a $13 billion company based in Denver.

He aired clips showing DaVita chief executive Kent Thiry riding into company meetings on a horse, dressed as a musketeer, referring to himself as a “mayor” and quoting from “The Man in the Iron Mask.”

Because federal guidelines do not require doctors to be on site at for-profit dialysis clinics, DaVita patients often reported feeling rushed, with employees allegedly cutting corners for the sake of speed.

Megallan Handford, a former DaVita nurse who claims he was fired for trying to unionize its employees, told Oliver the company's focus “was all about numbers,” sometimes at the expense of patient safety.

“When I was working at DaVita, the priorities for transitioning patients was to get them on dialysis and get the next patient on as soon as possible,” Handford told Oliver. “You would have sometimes 15, maybe 25 minutes to get that next patient on the machine, so you were not properly disinfecting.”

Oliver ran through other complaints that have been made against DaVita, including questionable doctor referrals and accusations that the company purposely wasted drugs to be able to bill the federal government more.

“If it's beginning to feel like DaVita is being run like a volume business …” Oliver started, before cutting to a clip that showed Thiry comparing his management of DaVita to that of Taco Bell. (Before the show ended, Oliver would apologize — to Taco Bell.)

Toward the end of his segment, Oliver emphasized that problems with the for-profit dialysis industry were not limited to DaVita.

He also called for better government oversight, as well as improved incentives for kidney transplants and health care “to keep out of dialysis in the first place.”

Oliver also praised those who were willing to donate one of their two kidneys while still alive.

“For the rest of us complete a--holes,” Oliver encouraged people to register to become organ donors and suggested spreading the word through a Twitter hashtag:

Soon, #WhenIDiePleaseTakeMyKidneys began spreading across Twitter, with people chiming in to share their stories of suffering from kidney disease or organ donation.

Oliver closed with a tongue-in-cheek “commercial” for Taco Bell.

“Because we're nothing like dialysis clinics,” the commercial declared. “For a start, you may actually be more likely to find a doctor in one of our restaurants than in a dialysis clinic.”

Correction: An earlier version of this story incorrectly reported that DaVita CEO Kent Thiry refers to himself as a “mare.” Rather, he calls himself the “mayor” of the company.

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