Preop cardiac stress test hampers timely surgery for hip fracture

Preoperative cardiac stress tests in hip fracture patients lead to unnecessary surgical delays and prolonged hospital stays, according to researchers at the Mayo Clinic in Rochester, MN. The group suggested that routine stress testing was not necessary, as screening with either dobutamine stress echocardiography or sestamibi scans had very little impact on patient management."Certainly, hip fractures represent an injury, but they often reflect the general poor health of these elderly patients," said Dr. Stephen Sems."Noninvasive cardiac stress testing is often recommended to assess hip fracture patients at risk for perioperative cardiac events." He presented findings at the 2007 American Academy of Orthopaedic Surgeons (AAOS) meeting in San Francisco."Cardiac stress evaluation provides information about the maximal tolerable heart rate before ischemia develops and can also provide information about the function and efficacy of the heart under stress. Its usefulness in patients awaiting fixation of hip fracture is unknown," Sems said.For this retrospective study, Sems' group looked at 1010 proximal femur fractures in 973 patients treated between 2001 and 2006. The average age of the patients was 83, and 72% were female. Fifty-four of the 973 patients underwent preoperative cardiac stress testing. Among those 54, 12 dobutamine stress echocardiography (DSE) tests and one sestamibi scan were positive for ischemia. As a result of a DSE scan, one patient underwent coronary bypass grafting prior to hip fracture fixation, which was done 11 days after her admission. She died 48 days later of respiratory failure, Sems said.Overall, no significant difference in mortality rates appeared between the 54 patients who underwent stress testing and the remaining patients who did not, Sems said. The overall mortality rates were 7.2% at 30 days postsurgery, 13.9% at 90 days, and 27.2% at one year. Cardiac screening did, however, affect the average time to surgery: 2.76 days for those who had the stress test versus 1.41 days for those who did not (<p = 0.004).The researchers concluded that the utility of a stress test in the hip fracture patient population was limited and that the risks associated with surgical delay outweighed any potential benefits. AAOS session moderator Dr. Bruce Ziran asked Sems how he convinced his colleagues in anesthesiology to skip the stress test, as they often consider it mandatory. Sems replied that he advocated that anesthesiologists treat all hip fracture fixation patients as if they are on the verge of an ischemic attack. By keeping a patient's heart rate and blood pressure low in order to avoid tachycardia, hypertension, and anemia, Sems said that he believed it was possible to eliminate the need for the stress test.For more information from the Diagnostic Imaging archives:Fractures and liver lesions top list of residents' ER missesPercutaneous osteoplasty proves as hip as surgeryEcho maintains crucial role in clinical cardiac practice