Research from the International Surgical Outcomes, they conducted work anaesthesia, where It indicates that poor patient outcomes are common after planned (elective) in-patient surgery, and that mortality rates following complications are at broadly similar levels in the poorest and wealthiest countries although patient populations may differ. The study published in the British Journal of Anaesthesia.

Lead author, Professor Pearse, said: "This survey is the most extensive of its kind ever performed. Whilst most patients having planned surgery did not experience any problems, a large number of patients did develop complications and many of them did not survive."

Four hundred and seventy four hospitals in 27 high, middle and low income countries participated over a seven day period and data from 44,814 patients following routine, non-emergency surgery were analysed. The study compared different types of surgery with the frequency of adverse outcomes, and quantified the range of complications occurring and their severity.

Primary findings

The survey found that one in six patients (16.8 per cent) developed complications in hospital, and that one in 35 of those patients (2.8 per cent) subsequently died without leaving hospital. The figures based on a seven day sample period suggest that over a 12 month period, 50 million patients suffer complications following surgery in hospitals, and that over 1.5 million die from those complications.

Most common complications

The most common complication following surgery was infection, and particularly superficial site infection, caused for example by bacteria on the skin around a surgical wound. The study found that 2.9% of patients suffered from such infections, which equates to nine million patients worldwide, every year. Of those patients, 1.3^ died from the infection (117,000 patients annually).

Surgical procedures and their association with complications

The survey assessed different categories of surgery and their association with complications. Researchers found the type of surgery which carried the greatest risk of complications worldwide to be upper gastrointestinal – that is surgery involving the oesophagus, stomach and small bowel. The surgery carrying the greatest risk of mortality following a complication was cardiac procedures. By comparison, the procedures carrying the least risk of complications related to orthopaedics, and breast procedures.

The researchers concludes that too many patients are suffering adverse outcomes and too many are dying due to complications. Better planned care around the time of surgery might prevent many of these cases. They want to see more robust auditing of all outcomes following surgery.

In further studies they believes there needs to be a fresh focus on care aimed at reducing post-operative complications which can not only severely impact of patients' lives, but are a huge burden on the world's health services.