Preoperative Neutrophil-to-Albumin Ratio and Post-Induction Hemodynamic Vulnerability in Major Oncologic Surgery

This prospective observational study aims to evaluate whether the preoperative neutrophil percentage-to-albumin ratio (NPAR) is associated with post-induction hemodynamic vulnerability in adult patients undergoing elective major oncologic surgery under general anesthesia. NPAR will be calculated from routine preoperative laboratory results by dividing the neutrophil percentage by the serum albumin level. No additional laboratory tests, medications, invasive procedures, or changes in anesthesia management will be performed for the purposes of the study. Demographic characteristics, preoperative laboratory values, anesthetic data, and hemodynamic measurements will be recorded prospectively. Hemodynamic status will be evaluated during the period between induction of general anesthesia and surgical incision, with a maximum observation period of 20 minutes. Vasopressor use and administered doses will also be recorded. The study will assess the ability of preoperative NPAR to identify patients who may be more susceptible to early hemodynamic instability following induction of general anesthesia.

Inclusion Criteria: * Age 18 years or older * Scheduled for elective major oncologic surgery * Undergoing surgery under general anesthesia * Availability of preoperative complete blood count and serum albumin -measurements * Standard hemodynamic monitoring * Provision of written informed consent for participation in the study Exclusion Criteria: * Age younger than 18 years * Emergency surgery * Preoperative hemodynamic instability * Preoperative vasopressor or inotropic support * Sepsis or active infection * Hematologic malignancy * Advanced cardiac, renal, or hepatic failure * Pregnancy * Missing preoperative laboratory data -Inability to complete the 20-minute post-induction evaluation period-