The aim of this observational study was to detect myocardial damage by monitoring high-sensitive troponin I levels in patients undergoing below-knee extremity surgery with peripheral nerve block.

The primary question it aims to answer is:

How effective are peroperative high-sensitive troponin I levels in predicting myocardial damage?

High-sensitive troponin I levels will be monitored intraoperatively and at 24 and 48 hours postoperatively.

Peripheral nerve blocks are becoming increasingly popular in foot and ankle surgery. Patients undergoing peripheral nerve blocks have advantages such as shorter hospital stays, better postoperative pain relief, lower costs, and less opioid use.

A review of current literature revealed that myocardial damage has not been investigated in patients scheduled for below-knee lower extremity surgery. Therefore, we aimed to detect myocardial damage by monitoring high-sensitive troponin I levels, which is considered the most sensitive and effective test according to AHA/ACC (American College of Cardiology and American Heart Association) guidelines at our hospital. The secondary aim of the study was to determine which parameters correlate with myocardial damage.

Preoperatively, the patient's hemogram, biochemistry, and hsTroponin I measurements, all of which were requested during the preparation phase, will be recorded.

During the operation, the type of anesthesia, the amount of local anesthetic and adjuvant medication used for peripheral nerve blockade will be recorded.

Intraoperatively, routine anesthetic monitoring (SpO2, blood pressure, ECG, heart rate), intraoperative presence and duration of hypotension, need for inotropic support, total dose (if any), presence and duration of tachycardia and bradycardia, fluid volume administered, urine output, and operation time will be recorded.

Postoperatively, all patients will be monitored in their ward or intensive care unit. Routine hemogram, biochemistry, and hsTroponin I measurements will be repeated at 24 and 48 hours, and the results will be noted. Postoperative complications will be recorded.

Patients will be followed up for 30 days through the hospital registry and telemedicine at the investigator's discretion, and will be questioned about potential major cardiac events (MACE).

Inclusion Criteria:

• Patients over 18 years of age
• Patients undergoing below-knee lower extremity surgery
• Patients with ASA classifications I, II, III, and IV
• Patients who have consented before the procedure
• Patients who are literate and able to give consent

Exclusion Criteria:

• Patients in whom regional anesthesia is contraindicated
• Patients who refuse to participate in the study

Patients undergoing below-knee lower extremity surgery under peripheral nerve blockade

general demographic information, contact information, work names