Patients have been facing long waits for treatment in A&E after hospitals struggled to meet targets.
Just 86.6 per cent of patients were seen within four hours in A&Es at Mid Yorkshire Hospitals Trust in December, against a target of 95 per cent.
The figure for November was 81.2 per cent at the organisation, which runs Pinderfields, Pontefract and Dewsbury hospitals.
A report to Mid Yorkshire’s meeting said that in December there were 19,024 A&E attendances and more than 2,500 people waited more than four hours to be either admitted to hospitals, transferred or discharged.
Between April and November the trust had the third highest number of A&E attendances among 140 NHS organisations in England.
On one day in November, six patients waited longer than 12 hours in A&E to be admitted to hospital. The report said no harm was caused to patients by the delays.
Patients have also been left waiting in ambulances to be handed over for treatment by A&E staff.
In December there were 226 ambulance handovers which took more than 30 minutes, against a target of zero.
December also saw 41 ambulance handovers take more than 60 minutes.
Latest figures were published as Mid Yorkshire seeks to speed up a shake-up of services which will see A&E care centralised in Wakefield.
Critically-ill and injured patients could be taken to Pinderfields Hospital from September - six months earlier than planned after the trust was criticised by the Care Quality Commission over staffing levels patient safety.
Health bosses in Calderdale and Huddersfield have also announced plans to centralise A&E care in Halifax. The move could leave the whole of Kirklees with no full A&E.