Medical mishaps strike one in 10

By MONIQUE DEVEREUX health reporter

One in 10 people admitted to hospital each year will suffer from some kind of medical misfortune, a public health study has found.

The unlucky patient could be the victim of a medical mistake or an unforeseeable event, such as a previously unknown allergic reaction to a prescribed drug, says the New Zealand Quality in Health Care study.

The research, released today, measures "adverse events" - cases of unintended patient injury, disability or death - recorded by public hospitals.

Applied across the whole population, the results would equate to problems affecting 68,000 of the 680,000 people admitted to hospital on average each year.

Adverse events recorded range from a post-operative infection extending the patient's hospital stay through antibiotic-induced diarrhoea to death.

Today's findings have not surprised medical specialists, who say improvements to hospital systems have already been made and more are in the pipeline.

Headed by Professor Peter Davis, who is based at Otago University's School of Medicine in Christchurch, the study looked at 1326 cases taken from three Auckland hospitals' 1995 records.

It found that 142 cases - about 10 per cent - could be labelled "adverse events."

More than half of those resulted in a temporary disability for the patients, who on average had to remain in hospital for a further six days.

Around 0.6 per cent of patients from the Auckland case studies died.

If applied on a nationwide average that would equate to about 4000 of the 680,000 people admitted to hospital each year dying as a result of an adverse event.

Professor Davis' study found that in half of the adverse cases, the event happened after the patient was admitted.

A high proportion - almost 60 per cent - were not preventable, or there was not enough evidence to say if they were preventable. A third of all cases identified stemmed from care given outside the hospital, and were mainly medication-related.

For example, an elderly man was admitted to hospital after finding blood in his urine. Investigations discovered the problem was the result of his being prescribed the wrong level of medication.

Although the case would be labelled an adverse event in the hospital notes, the hospital itself was not to blame.

The study found most adverse events were caused not by individuals but by medical systems failure - something medical specialists say can be properly addressed only with increased finance.

Middlemore Hospital's chief medical officer, Dr Ian Brown, said the study was a positive document that would help the medical profession improve the quality of its systems.

"Health workers are only human and there will be mistakes made from time to time. But if we know where those mistakes are happening we can learn from them and adapt to try and ensure things change."

Professor Davis said that despite the findings being largely positive, more adverse events could be prevented by introducing systems designed to prevent human error.

The Health Research Council financed the study.