Doctors in the UK have shared their fears over 250 ventilators purchased from China and called for their 'withdrawal and replacement'.

Medical experts from the Sandwell and West Birmingham NHS Trust warned that the Shangrila 510 model, made by Chinese firm Beijing Aeonmed Co. Ltd., caused 'significant patient harm including death' if used in a hospital environment.

In a letter seen by NBC News, the senior doctors revealed the breathing machines, which were built for ambulances rather than hospitals, not only had a problematic oxygen supply but could not be cleaned properly. 

The five-page document, which was seen by the news organisation on April 13, read: 'We believe that if used, significant patient harm, including death, is likely.

'We look forward to the withdrawal and replacement of these ventilators with devices better able to provide intensive care ventilation for our patients.'

The complaints came after a shipment of 300 Chinese ventilators were flown into the UK on April 4 - a development hailed by Michael Gove in one of the Government's daily virus press briefings and tweeted about by Foreign Secretary Dominic Raab. 

It is not clear how many were sent by Beijing Aeonmed, whether any other NHS hospitals received shipments of the ventilators or how much was paid for them. 

The Sandwell and West Birmingham NHS Trust medics explained that the device made by the Chinese manufacturer provided an oxygen supply which was 'variable and unreliable'.

Alongside the device having only a 'basic' build, the fabric case on the device could not be cleaned properly by staff.

The doctors went on to say that the machines, which also arrived to the UK with a 'non-E.U.' oxygen connection hose, were designed for ambulance use rather than for hospitals and left NHS staff having to create makeshift stands for the device out of a hospital trolley.

In addition, the ventilators had an unfamiliar design to doctors in the UK and came with an instruction manual that was confusing.  

The document, which was written by a senior anaesthesia and intensive care doctor representing a group of clinicians and senior managers in and around Birmingham, comes as the UK continues to control the spread of the virus which has now claimed the lives of 26,570.

Earlier this month, ministers confirmed that they had purchased and unloaded 300 ventilators from China at the military base MOD Donnington in Shropshire.  

Following the arrival of the devices, Secretary of State for Foreign Affairs Dominic Rabb tweeted: 'Today we received 300 ventilators purchased from China, for @NHsuk hospitals. Thousands more due in the coming weeks.

'Large shipment of masks and protective equipment has also arrived, flown from Shanghai by @virgin. Thanks @ukcinchina for helping deliver these life-saving supplies.' 

While Michael Gove said during a Downing Street briefing: 'Today 300 new ventilators arrived from China. I'd like to thank the Chinese government for their support in securing that capacity.'