A secondary analysis of the Turkish National Perioperative Transfusion Study (TULIP TS) database will be performed.

The Turkish National Perioperative Transfusion Study (TULIP TS) was conducted by The Turkish Society of Anesthesiologists' Multicentre Clinical Trials Network.

TULIP TS included 6481 patients undergoing major elective surgery, from 61 study sites across the country.

Transfusion practices of clinicians working at diverse surgical fields; differences between current transfusion practices and patient blood management strategies; the areas for improvement and the obstacles that could prevent change were evaluated and identified.

Data relevant to perioperative transfusion rates of red blood cells, fresh frozen plasma and platelets, the indications for transfusion and postoperative adverse outcomes including 1 month all cause mortality was obtained.

The TULIP TS group aims to collect further data concerning 1 year all cause mortality of the same patient population and to evaluate adverse outcomes in transfused and non transfused patients.

Inclusion Criteria:

• Patients undergoing major elective surgery

Exclusion Criteria:

• Trauma patients, emergency surgery

Patients undergoing major elective surgery in General surgery Orthopedics Urology Transplantation surgery Neurosurgery Gynecology and obstetrics Cardiovascular surgery