Her coarse hands gripping a blue plastic ventilator she pumped by hand for years to keep her injured son alive, Wang Lanqin sits by her child's bed.

Wang and her husband Fu Minzu took turns for years pumping the device to help their son Fu Xuepeng breathe, as they could not afford the fees for him to be cared for in hospital after he was paralysed in a motorbike crash.

The couple's hands became deformed from two years of pumping the device thousands of times a day, media reports said, but their load was lightened after they built a primitive mechanical ventilator with help from relatives.

Pictures show the rusty, oil-flecked machine, which incorporates a plastic milk bottle, standing on wooden tables held in place with slabs of rock and connected by tube to their son, who lies in bed wearing a red hat to protect him from the cold.

Even after building the machine, to avoid paying expensive electricity bills the couple kept up their hand-pumping routine during the day, as well as providing round the clock care for their son, who is paralysed but conscious.

After they were widely circulated in Chinese media, the images prompted a flurry of donations to the couple who are from a village in Huangyan district in the eastern province of Zhejiang.

These included cash and a modern ventilator sent by a Beijing company.

China has vastly expanded health insurance schemes in rural areas over the last decade, but payouts are still low, leaving severely or chronically ill patients dependent on family members to pay their medical bills.

The couple "never think of giving up, not for one second," Fu Minzu told the China Daily newspaper. "No parents would give up on their child as long as there is a slight chance of living."