Examination of blood samples is inevitable in intensive care units. Routine blood samples can be an important cause for anemia. In this study, we aimed to examine how our blood collection routine affects hemoglobin values.

Blood tests for follow-up and treatment are widely used in intensive care units (ICU). Although its etiology is very diverse, phlebotomy performed due to frequent laboratory tests is among the preventable causes of anemia. In this observational study, blood tests performed on patients treated in intensive care units followed up in our clinic between 01.April.2023 - 31.May.2023 (2 months) will be examined. Patients' age, presence of additional disease, indication for admission to the unit, Acute Physiology and Chronic Health Assessment II (APACHE II), Sequential Organ Failure Assessment (SOFA) and Glasgow coma scale (GCS), hemoglobin values will be recorded. The daily blood test will record the amount of blood drawn for analysis (in milliliters), where it was taken from (peripheral, central venous or arterial catheter), and the amount of excess blood. Statistical analysis will be performed in terms of patient characteristics, routine blood volumes and development of anemia.

Inclusion Criteria:

• Patients followed in the intensive care unit for more than 48 hours, ≥18-year-old

Exclusion Criteria:

• Patients not followed up by our clinic,≤18-year-old

Patients over the age of 18 who were followed up in the intensive care unit by our clinic and treated for more than 48 hours were included in the study.