Cancelled operation rates remain higher than planned at the Westcountry's largest hospital, despite years of focus on the problem.
The latest figures show 69 procedures at Derriford Hospital in Plymouth were cancelled on the day of surgery in July.
A hospital report states the main reasons were theatre lists overrunning, emergencies taking priority and poor availability of general beds.
It adds that work is ongoing to improve intensive care availability, pre-operative work and planning.
Derriford managers have been striving to bring down cancelled operation rates to the national standard of 0.8% for more than five years. The July rate was 1.32%.
A hospital spokesman said: "We strive to offer the best possible care for all our patients and only consider postponing operations when there is no other suitable clinical alternative."
The hospital recorded among the country's highest number of cancelled operations in 2007/8 – 1,346 planned procedures on the day of surgery.
This equated to 2.4%. The rate dropped to 1.9% in 2009/10 and 1.6% in 2010/11.
Monthly rates dipped to 0.88 in August last year, but have since fluctuated.
Efforts to reduce rates come amid Derriford's £54 million savings plan over two years.