A new online tool, available to surgeons and the public, will let you know if a planned surgery puts you at risk.

Making difficult decisions about whether to have a potentially risky surgery just got easier for doctors and patients.

The American College of Surgeons (ACS) has unveiled a new surgical risk calculator. This online tool allows anyone with a computer and an Internet connection to punch specific information into a Web page to find out potential outcomes before ever going under the knife.

When using the calculator, surgeons enter 22 preoperative risk factors about their patients, including age, weight, and medical status. The tool calculates the risk of death, as well as eight all-too-common complications, including pneumonia, heart problems, surgical site infections, urinary tract infections, blood clots, and kidney failure. It even calculates the estimated length of the patient’s hospital stay.

The calculator is available to anyone, as long as they have the medical knowledge necessary to understand and input the data.

Dr. Clifford Ko, director of the ACS Division of Research and Optimal Care, told Healthline that the calculator is the result of many years of collecting reliable data through the ACS National Surgical Quality Improvement Program (NSQIP).

The calculator works for just about any operation. The data come from hospitals large and small and from a variety of communities, both rural and urban, across the U.S.

The data is adjusted to take into account whether it comes from a hospital that generally sees sicker patients with poorer outcomes, for example. “It levels the playing field, so we can compare the Mayo Clinic to a general hospital in the middle of Wyoming,” Ko added.

Patient information regarding surgical outcomes is collected from clinical records. Instead of the surgeons themselves, hospital employees who have been rigorously trained in collecting the information input data about mortality and complications. “Providers are hard-pressed to say they’ve had complications,” Ko said.

If a particular hospital is not in the database, information from a similar facility is used.

Patients demand reliable estimates of mortality rates. “Having surgery is no longer the way it was 50 years ago, when someone would tell their doctor, ‘Whatever you say, doc.,’” Ko said. “Now, the patient comes in and they’re better educated, thanks to the Internet.”

The tool gives patients the information they need to avoid surgeries that may not be worth the risk. “When someone goes in for an operation for colon cancer, that’s usually the only way to cure it, and the indications are pretty solid,” Ko said. “Other procedures may only be for a symptom, or maybe it’s a mole on their shoulder that’s unsightly. If the risk is low, that’s fine, but if the risk is high, somebody might think, ‘I don’t like the way this mole looks, but if the complication rate is so high, I will accept it.’”

Perhaps the best thing about the surgical risk calculator is that it lets doctors know what could go wrong during an operation. As a result, the hospital is prepared with the equipment and personnel necessary. “We’re being proactive,” Ko added. “No more yelling, ‘Get to the ICU, stat!’ We can avoid all that.”

In a news release, the ACS reported that the Centers for Medicare and Medicaid Services (CMS) may soon provide a financial incentive for surgeons to calculate the risks of operations using the online tool. A representative of CMS declined Healthline’s request for comment.

Dr. Karl Bilimoria, director of the Surgical Outcomes and Quality Improvement Center at Northwestern University in Chicago, led a study on the calculator using information from almost 400 hospitals and 1.4 million patients nationwide. The results have been published online in the Journal of the American College of Surgeons.

The study was funded in part by the Agency for Healthcare Research and Quality (AHRQ), a division of the U.S. Department of Health and Human Services. “We are still reviewing the new surgical risk calculator, but we think it’s a positive development for surgeons and their patients to discuss the risks and possible post-surgical complications related to various procedures,” said James Battles, Ph.D., a social science analyst for patient safety at the agency, in a statement to Healthline.

Ko stressed that the calculator is not intended to replace the knowledge of a surgeon when it comes to making decisions about life and death.

In fact, the calculator helps surgeons make better decisions, Ko said. Previously, doctors would look at textbooks or journal articles for background on surgical complications, but that doesn’t take all of a patient’s individual risk factors into account.

The calculator includes a function which allows surgeons to adjust for risk based on their subjective assessment of the patient.

Dr. Timothy Gardner, a renowned heart surgeon who spoke to Healthline on behalf of the American Heart Association, said the calculator is based on “good, solid, clinical data.” He called it a “terrific step forward,” adding, “It’s time for many of physicians, especially in the paternalistic area of surgeries, to view patients and their families from a consumer perspective.”