A new study conducted by a team of John Hopkins doctors finds that medical errors could be responsible for more annual deaths than such notorious respiratory diseases as emphysema and bronchitis.

Published in the latest issue of BMJ, the study concludes medical mistakes are now the third overall leading cause of death, behind only such conditions as heart disease and cancer.

Researchers Find Most Errors go Unobserved

The study also concludes that most of the errors go unobserved, never to be documented as part of the official record.

Overall, doctors estimate that at least 251,454 deaths stemming from medical error take place here in the U.S. on an annual basis. The report stresses that researchers believe the number is actually much higher when home and nursing home deaths are factored into the equation.

Even the on-record figures are more than 25 percent greater than the 180,000 per year deaths the U.S. Department of Health and Human Services office reported as an annual average in 2008.

"We have to make an improvement in patient safety a real priority," said Dr. Martin Makary, a professor of surgery and health policy and management at Johns Hopkins who joined Dr. Michael Daniel in conducting the study.

Researchers also noted one of the primary reasons why the numbers from all the various studies seem to differ so sharply has to do with the way records are kept. Currently, the cause of death on a certificate has to align with a specific billing code, a system that does not adequately take into account human error.

Billing Codes Neglect to Highlight Human Mistakes

"Billing codes are designed to maximize billing rather than capture medical errors," Makary said.

One specific example of such an instance highlighted by researchers in the study involved a patient who had a successful organ transplant, but soon had to be re-hospitalized for a non-specific compliant.

During tests administered during the second visit, a doctor accidentally cut the patient's liver, causing internal bleeding and ultimately leaving her in cardiac arrest. When the patient later died, the death certificate made no mention of the doctor's error and listed a cardiovascular issue as the cause of death.

Makary believes that another critical issue stems from many hospitals not investing in the kind of technology that could prevent errors.

"There is a strong moral case for innovations in this area, but there isn't really a financial case for hospitals to improve this system the way it is," he said, noting that research funding in the area of medical error is extremely limited.