NHS England said 2,077 inpatient appointments and 3,187 day case appointments have been cancelled.
The organisation said it is doing ‘everything possible’ to ensure safe emergency care is being provided to minimise the impact of the strike.
A spokesman for NHS England said: “NHS England once again expressed regret for the disruption patients will face and the fact that thousands of planned procedures will have to be rearranged, leaving people having to wait longer for treatment.
“However, it is expected that careful planning in scheduling operations during the proposed period of industrial action will have minimised the numbers of cancelled operations.”
Doctors are striking after the government announced it would be imposing a new contract which proposes a 13.5 per cent rise in basic pay for junior doctors.
However, the number of hours during the week which are classed as ‘unsociable’ and therefore better paid – are being cut. This includes Saturday.
Hospitals in Sussex which are affected are: East Sussex Healthcare Trust, which runs Eastbourne DGH and Conquest Hospital in Hastings, Western Sussex NHS Foundation Trust, which runs St Richard’s Hospital and Worthing Hospital, Surrey and Sussex Healthcare Trust, which runs East Surrey Hospital and services at Horsham and Crawley Hospital and Brighton and Sussex University Hospitals Trust, which runs Princess Royal Hospital in Haywards Heath and the Royal Sussex County Hospital in Brighton.
Dr Anne Rainsberry, National Incident Director for NHS England, said: “This is clearly going to be a difficult couple of days. A 48-hour strike will put significantly more pressure on the NHS and the cumulative effect of these recurring strikes is likely to take a toll.
“The safety and care of patients is always our number one priority and staff across the NHS are doing all they can to minimise the impact on patients of the action.
“We will closely monitor events as they unfold to ensure plans to deal with the pressures are robust and people are ready to respond to any emerging difficulties.”
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