Hospitals are trying new early-warning systems to monitor patients for subtle but dangerous signs of a worsening condition.

After surgery or during hospitalization for illness, patients are at risk for complications that can quickly turn fatal, such as a depressed breathing rate that can lead to cardiac arrest caused by over-sedation or an adverse reaction to narcotic pain medications. Patients can show signs of deterioration—known in medical terms as “decompensation”—as many as six to eight hours ahead of a cardiac or respiratory arrest, studies show.

But the signs aren’t always picked up or acted upon by staff. Patients on general medical and surgical floors are usually not monitored 24/7 unlike patients in intensive care units, who are hooked up to multiple machines and monitors.

Among the strategies hospitals are adopting is a wireless monitor that slips under a mattress and alerts nurses to changes in breathing and heart rate. Another approach rates a patient’s risk of serious deterioration in real time based on lab results, vital signs and nurses’ assessments gathered from electronic medical records.

“We have to be able to profile patients according to their risk, and then manage the high-risk group,” says David Westfall Bates, chief quality officer and chief of general internal medicine at Brigham and Women’s Hospital in Boston and a professor at Harvard Medical School.

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