1. To analyze the association of different doses of opioids on myocardial injury/protection through BMP-6/SMAD pathway. 2. To observe the effect of different doses of opioids on the expression of BMP-6 in bone marrow. 3. To investigate the relationship between different doses of opioids and BMP-6 and perioperative cardiovascular adverse events in patients with lower extremity fracture surgery.
There were 160 patients aged 18-65 years and older who needed surgery for lower extremity fracture.
ASA grades I to III, gender is not limited.
Patients with acute myocardial infarction in the last 6 months, those with a history of heart failure, and those with elevated troponin levels before injury.
Old fracture
Stroke patients
Liver cirrhosis, kidney failure