A Wigan man has been given a 14-month suspended sentence for attacking two paramedics, leaving one with a broken wrist.
The head of West Midlands Ambulance Service said he was "almost lost for words" after 23-year-old Adam George James was given a 14-month suspended sentence at Birmingham Crown Court.
The Attorney General has been urged to review the non-custodial sentence.
James, from Housley Close, Wigan, was also ordered to carry out 150 hours of community service and pay a victim surcharge, the ambulance service said.
One paramedic had her wrist broken and another suffered cuts and bruising to his lower legs after being kicked by James - who was wearing steel toe-capped footwear - while they tried to help him.
The offence occurred on July 12 last year after James was found unconscious in a public place in Birmingham city centre.
The chief executive of West Midlands Ambulance Service, Anthony Marsh, said: "The sentence is extremely lenient given the traumatic injuries sustained and emotional upset experienced.
"There is no question in my mind that this warranted a custodial sentence. As well as the pain, suffering and emotional scarring of these staff, the public lost the services of two highly trained ambulance clinicians for a total of eight weeks.
"Those shifts had to be covered which meant overtime and additional cost to the NHS at a time when budgets are already stretched."
Mr Marsh added: "I'm almost lost for words.
"Here we have a situation where despite the crew's best efforts, they were both seriously assaulted - one of which resulted in the bones being broken in her wrist - and the defendant wasn't given a custodial sentence.
"I have written to the Attorney General to ask them to review this case. I do personally feel that the sentence that has been passed is far too lenient."
Paramedic Amy Holtom, who suffered the broken wrist, said: "I think this is appalling and shows how little the courts think of us.
"Anyone else would have been looking at time in jail, but yet again ambulance staff have been let down by the legal system."
A private members' bill proposing tougher penalties for attacks on emergency workers put forward by Labour MP Chris Bryant was debated in Parliament last month,
The Assault on Emergency Workers (Offences) Bill seeks to double the maximum sentence for common assault from six months to a year if committed against an on-duty emergency worker.
West Midlands Ambulance Service's head of security, Steve Elliker, said: "Whilst we welcome the new private members' bill to provide emergency workers with enhanced protection, the Ministry of Justice has made it quite clear that there is no reason why the courts cannot hand down custodial sentences based on current legislation.
"It is almost unbelievable that even this level of violence did not result in a custodial sentence."
A spokesman for Birmingham Crown Court said James was sentenced last Wednesday after admitting charges of assault causing actual bodily harm and assault by beating