Patients Presenting with Acute Myocardial Injury with Hip Fracture Have Greater Survival with Rapid Surgical Care

Commentary Current evidence and clinical experience strongly support the principle that elderly patients with a hip fracture are best served by prompt surgical repair1. Although consulting physicians and assigned anesthesiologists often believe that medical management and testing are needed preoperatively, the resulting surgical delay typically worsens early survival without any beneficial effect. There are ample published data confirming that a delay to reverse anticoagulation or to perform echocardiography does not improve outcomes or help avoid complications2–4. Although there is some controversy regarding the preferred time to surgery, 48 hours appears to be the upper limit of acceptable delay and 24 hours may be the ideal window5. The HIP ATTACK trial was carried out to determine if even more accelerated surgery—i.e., performed within 6 hours—provided additional benefit over a 24-hour delay. The authors of that study found that accelerated surgery performed within 6 hours did not significantly lower the risk of mortality or a composite of major complications compared with surgery performed within 24 hours6. Of the 1392 patients in the HIP ATTACK trial, 47% had a preoperative troponin level recorded and 23% of the 1392 had an elevated level indicating preoperative myocardial injury6. Despite this evidence of myocardial injury, patients were randomized per the study protocol. In the present substudy involving the patients with preoperative troponin measurement, surgery within 6 hours reduced early mortality by approximately half in those with an elevated troponin level whereas, in the group without evidence of myocardial injury, accelerated surgery provided no benefit compared with surgery delayed for 24 hours. This result suggests that patients with a hip fracture and concomitant myocardial injury may have better survival with fewer complications when the physiologic stress of the fracture is relieved in as little time as possible. Conversely, if the stress is prolonged for even 24 hours, the mortality rate may be doubled. As pointed out by the authors, these results are similar to those in previous cohort studies demonstrating that preoperative myocardial injury is common in patients with a hip fracture (range, 15% to 30%) and carries a poor prognosis. Currently, there are no clinical guidelines on how to manage those patients. Unfortunately, this substudy is probably underpowered. If its findings can be corroborated, they should provoke a new approach to the care of elderly patients with a hip fracture. As suggested by the authors, the observed myocardial injuries may have been a consequence of the physiologic stress induced by the hip fracture and are a marker of poor cardiac reserve. The stress is likely related to pain and inflammation from the fracture, and ischemia may be compounded by dehydration, bleeding, and hypoperfusion. As suggested by this study, early surgery may provide rehydration, cessation of bleeding, and pain relief, thereby reducing the stress response and critically reducing cardiac workload and cardiac injury. The key points are that the stress needs to be relieved as quickly as possible and that delay for even 24 hours increases mortality and morbidity in this frail population with little reserve. Because surgery within 6 hours may be impractical in many hospital settings, alternative approaches to reduction of this stress are needed. Can this be achieved with better clinical protocols that improve care in the preoperative period? Future studies need to assess if pain relief with long-acting intra-articular and peripheral nerve blocks might provide needed pain relief when given upon admission. Intravenous hydration, appropriate transfusion, and anti-inflammatory medications might also help blunt the stress/inflammatory response. The HIP ATTACK Investigators have clearly documented that approximately 20% of patients presenting with hip fracture have concomitant cardiac injury that demands immediate treatment. Their data support the idea that immediate surgery may play a role in relieving the stress related to the fracture, thus providing a better chance of survival. They also demonstrated that the preoperative period following hip fracture is a critical period that definitely impacts morbidity and mortality. These revelations need to be acted upon. Surgical treatment of hip fractures should be expedited as much as possible. The time to surgery after a hip fracture must become a quality-of-care metric. Future studies are needed that corroborate the HIP ATTACK data and provide a better understanding of the stress response that results from hip fracture. Hopefully, this research will lead to new and improved protocols for preoperative management of these frail and critically injured patients.