The Coronavirus Disease 2019 (COVID-19) pandemic has resulted in persistent health problems in a significant proportion of individuals after recovery from the acute infection. These long-term manifestations, commonly referred to as post-COVID-19 condition or long COVID, may involve respiratory, cardiovascular, neurological, psychological, and general health domains. Understanding these sequelae is particularly important in patients undergoing preoperative anesthesia evaluation, as residual symptoms may influence perioperative risk assessment and clinical decision-making. This cross-sectional observational study aims to evaluate the long-term clinical and health effects of previous COVID-19 infection in adult patients presenting to the preoperative anesthesia clinic. Patients aged 18 years and older who report a history of confirmed COVID-19 infection will be included. Clinical data related to the acute infection period (disease severity, hospitalization, intensive care unit (ICU) admission, oxygen therapy, and radiological findings) will be retrospectively obtained from hospital records. At the time of preoperative assessment, participants will complete a structured post-COVID-19 clinical questionnaire to evaluate persistent symptoms across multiple organ systems. The study seeks to determine the prevalence and characteristics of long-term post-COVID-19 symptoms and to explore potential associations between acute disease severity and ongoing health complaints. No additional medical intervention will be performed as part of this research.

Inclusion Criteria:

• Age ≥18 years

Presentation to the preoperative anesthesia clinic

Self-reported history of laboratory-confirmed COVID-19 infection

Ability to provide informed consent

Willingness to complete the post-COVID clinical questionnaire

Exclusion Criteria:

• Age <18 years

No history of COVID-19 infection

Refusal to participate or incomplete questionnaire

Cognitive impairment or communication difficulties preventing reliable data collection

Adult patients aged 18 years and older presenting to the preoperative anesthesia clinic of Elazığ Fethi Sekin City Hospital who report a previous laboratory-confirmed COVID-19 infection. The study population consists of surgical candidates undergoing routine preoperative evaluation. Clinical information regarding the acute COVID-19 period will be obtained retrospectively from hospital records, and persistent post-COVID symptoms will be assessed at the time of preoperative evaluation using a structured questionnaire.