Carotid Doppler Parameters and Post-Induction Hypotension

Post-induction hypotension (PIH) frequently occurs after the induction of general anesthesia and has been associated with increased perioperative morbidity, including myocardial injury, acute kidney injury, and prolonged hospital stay. Patients undergoing gynecologic oncology surgery constitute a high-risk population due to malignancy-related physiological changes, advanced age, multiple comorbidities, and increased frailty. Despite this elevated risk, data focusing specifically on predictors of PIH in the gynecologic oncology population remain limited.

Carotid Doppler ultrasonography provides real-time information about cardiac output surrogates and preload responsiveness through parameters such as corrected flow time and peak systolic velocity. These measurements may offer a practical, non-invasive method for assessing hemodynamic reserve before anesthetic induction, particularly in high-risk oncologic surgical populations.

This prospective observational study includes adult patients undergoing elective gynecologic oncology surgery under general anesthesia. Pre-induction carotid Doppler ultrasonography will be performed to obtain flow-related parameters. Baseline patient characteristics will be documented, with particular emphasis on comorbidity burden assessed using the Charlson Comorbidity Index and functional vulnerability evaluated using the Clinical Frailty Scale.

Standard anesthetic induction will be conducted according to routine clinical practice. Blood pressure measurements will be recorded before and after induction, and post-induction hypotension will be defined according to predefined criteria.

The primary objective of the study is to evaluate the association between carotid Doppler ultrasonography parameters and the development of post-induction hypotension in the gynecologic oncology population. Secondary objectives include assessment of the relationships between comorbidity burden, frailty status, Doppler-derived indices, and perioperative hemodynamic outcomes within this specific patient group.

The results of this study may contribute to improved perioperative risk assessment and support the integration of carotid Doppler ultrasonography, comorbidity indices, and frailty evaluation into routine anesthetic practice for patients undergoing gynecologic oncology surgery.

Inclusion criteria

• Female patients aged 18 years or older
• Scheduled for elective gynecologic oncology surgery under general anesthesia
• Planned standard anesthetic induction
• Ability to provide written informed consent

Exclusion criteria

• Refusal to participate in the study
• Inability to obtain informed consent, including patients with dementia
• Emergency surgery
• American Society of Anesthesiologists (ASA) physical status IV or higher
• Cardiac rhythm other than sinus rhythm
• Autonomic nervous system disorders
• Atrial fibrillation with rapid ventricular response
• Pregnancy
• Sepsis or septic shock
• Significant valvular heart disease or peripheral vascular disease
• Anticipated difficult ventilation and/or difficult intubation
• Left ventricular ejection fraction <40%
• Severe aortic valve stenosis
• Morbid obesity (body mass index >40 kg/m²)
• Presence of implanted cardiac pacemaker or implantable cardioverter-defibrillator
• Chronic beta-blocker therapy
• Baseline mean arterial pressure <65 mmHg at admission
• Baseline systolic arterial blood pressure >190 mmHg or diastolic arterial blood pressure >110 mmHg