Six-Point Scale Predicts Joint Replacement Outcomes

Who is at risk for complications following joint replacement surgery and which patients will sail smoothly through the process without incident? Researchers at the Perelman School of Medicine at the University of Pennsylvania conducted two tests to find out.

In the first test, investigators examined the cases of 1, 012 patients who underwent primary total hip and knee replacement surgery over a 10-month period. They found that 70 patients had developed serious complications, most of which were cardiopulmonary in nature, including pulmonary embolism and cardiac arrhythmia. Of these, 11 suffered setbacks within 24 hours of their surgery, and 59 experienced complications just 24 hours later.

Doctors realized that if these 59 patients who experienced compilations had undergone same-day or short-stay surgery, and had been recovering at home when the complications occurred, they would have been at serious risk of injury.

As a result of the findings, the Penn team developed the six-point scale to determine a patient’s candidacy for same-day or short-stay total joint replacement. Patients without a history of chronic obstructive pulmonary disease, congestive heart failure, coronary artery disease, or cirrhosis have only a 3.1% probability of developing late, serious complications following joint replacement surgery.

However, patients with just one risk factor have nearly a 10% risk of complication, a risk that is compounded by the addition of other risk factors. Thus, patients with even one of these risk factors should not undergo outpatient or overnight total hip and total knee replacement. Instead they should be admitted to the hospital for traditional-duration surgery and recovery.

In the second study doctors examined 738 patients who had undergone total hip and knee replacement and found that patients who required admission to intensive or critical care units after surgery were likely to have a history of chronic obstructive pulmonary disease, congestive heart failure, coronary artery disease, chronic kidney disease, or suffering blood loss of more than 1, 000 milliliters during surgery or requiring vasopressors during surgery.

Based on the findings, the investigators developed a weighted Penn Arthroplasty Risk Score to predict which patients would require intensive or critical care intervention after knee or hip replacement.

Gwo-Chin Lee, M.D., senior investigator on both studies and an assistant professor of orthopedic surgery said, “Total joint replacements are very common procedures, but they can also pose significant health risks to certain populations, such as seniors. These two studies have provided us with better, more systematic and accurate ways of predicting before and after surgery, which patients are at greater risk for complications, allowing us to more accurately assess their conditions, and determine the appropriate course of treatment, care, and rehabilitation.”

He added, “Given the increased national emphasis on quality metrics and the need to ensure patients recover well following joint replacements, there is a need to better identify and predict post-operative complications so we can intervene and provide timely follow-up care, ”