Effect of Cardiorespiratory Changes on Carotid Flow Time During Lung Resection Surgery

Noninvasive Perioperative Hemodynamic Monitoring In Thoracic Surgery: A Prospective Observational Study

Cardiorespiratory changes during lung resection surgery, even though generally well tolerated, may lead to hemodynamic compromise, reducing venous return to the heart and hence cardiac output.

Carotid corrected flow time is widely regarded as non-invasive index of preload status, yet its dynamic relationship with cardiac output, especially in surgical population is not well-studied. Understanding how cardiorespiratory changes affect carotid flow time in anesthesized patients remains limited. This study investigates corrected carotid flow time response to anesthesia, lateral position, one-lung ventilation, open chest, capnothorax, lung recruitment and volume expansion, hypothesizing that cFT declines in association with CO reduction during lung resection.

The secondary interest of the study is to test whether carotid flow time and its recruitment-induced change can adequately predict fluid response during one-lung ventilation. In addition, the baseline preoperative carotid flow time and its position-induced change are studied as potential predictors of hemodynamic tolerance to lung recruitment and fluid response, respectively.

Finally, the purpose of this study is to see if cardiorespiratory changes and volume expansion affect cerebral blood volume during lung resection surgery.

Study Overview

• Status: Recruiting
• Conditions: Hemodynamic Monitoring

Detailed Description

In this study investigators look at intraoperative trajectory of secondary variables (hemodynamic and ventilatory) during cardiorespiratory changes and volume expansion to provide clinical context for primary variable response. A comparative analysis of all variables is performed in patients with different sex, ventilation protocol, operative side, tolerance to recruitment and fluid responsiveness.

• Study Type: Observational
• Enrollment (Estimated): 50

Contacts and Locations

• Study Contact: Name: Manuel Granell Gil Prof.; Phone Number: +34 609232031; Email: margry@uv.es

Study Locations

• Spain
  • Valencia, Spain
    • Recruiting
    • Hospital General Valencia
    • Contact: Prof. Manuel Granell, Dr; Phone Number: +34 609232031; Email: margry@uv.es

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Probability Sample

Study Population

Surgical population

Description

Inclusion Criteria:

• patients scheduled to undergo thoracosocpic lung resection surgery

Exclusion Criteria:

• carotid stenosis or abnormal anatomy of carotid artery that prevents visualization, emphysema, arrythmia

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort
Longitudinal study; Repeated measurements design

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in corrected carotid artery flow (ccFT) in association with cardiorespiratory changes and volume expansion during lung resection surgery	Doppler ultrasonography measurements are performed repeatedly at following timepoints: awake (seated), awake (supine), after intubation, after lateral decubitus position, after transition to one-lung ventilation, after pleura opening, after carbon dioxide insufflation, before lung recruitment, after first highest PEEP, after second highest PEEP, after optimal PEEP, before and after volume expansion. Statistical analysis: within-patient change (Friedman, Wilcoxon signed rank), correlation	enrollment phase (up to 2 years)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Diagnostic accuracy of corrected carotid flow time (ccFT) and recruitment - induced change in carotid corrected flow time (delta ccFTRM) in discriminating fluid responders during one-lung ventilation	Corrected carotid flow time (ccFT) is measured by Doppler ultrasonography immediately before volume expansion (VE) and 5 min after it. Recruitment - induced change in carotid corrected flow time (delta cFTRM) is calculated from measurments obtained by Doppler utrasonography immediately before recruitment maneuver (RM) and at highest PEEP. delta ccFTRM = (ccFT before RM - ccFTafter RM) / ccFT before RM Fluid response is defined as > 15% increase in cardiac output (CO) following volume expansion (VE). Volume expansion is a 200-250 ml bolus of crystalloid solution performed after the recruitment maneuver (RM) at the discretion of attending anesthesiologist. Measurements are obtained by pulse contour analysis after immediately before volume expansion (VE) and 5 min after it. Stat- ROC curve Outcome measure - prognostic ability (AUC)of corrected carotid flow time (ccFT) and recruitment - induced change in carotid corrected flow time (delta ccFTRM) in predicting CO increase.	enrollment phase (up to 2 years)
Diagnostic accuracy of baseline preoperative carotid flow time (ccFT) in discriminating between poor and good tolerance to recruitment maneuver and preoperative position-induced change in ccFT in discriminating fluid responders and non-responders.	Baseline preoperative carotid corrected flow time (ccFT) is a preoperative carotid Doppler measurement in seated position. Position-induced change (delta ccFT-P) is calculated from measurments obtained by Doppler utrasonography in awake seated position and within approxiamtely 10-15 minutes in awake supine position. delta ccFTP = (ccFT awake seated - ccFTawake supine ) / ccFT awake seated Poor tolerance to lung recruitment is defined as TWA-MAP of 20% decrease from baseline or absolute value < 65 mmHg measured during recruitment period or 10 min after. Measurements are obtained by pulse contour analysis from immediately before recruitment maneuver to 5 min after it. Fluid response is defined as > 15% increase in cardiac output (CO) following volume expansion (VE). Volume expansion(VE) is a 200-250 ml bolus of crystalloid solution performed after the recruitment maneuver (RM) at discretion of attending anesthesiologist.	enrollment phase (up to 2 years); statistical analysis (ROC); outcome measure - prognostic ability (AUC) of preoperative corrected carotid flow time (ccFT) and position - induced change in ccFT (delta ccFTRM) in predicting poor tolerance or CO increase
Change in cerebral blood volume index (CBVIl, CBVIr) in association with cardiorespiratory changes and volume expansion during lung resection surgery	Doppler ultrasonography measurements are performed repeatedly at following timepoints: awake (seated), awake (supine), after intubation, after lateral decubitus position, after transition to one-lung ventilation, after pleura opening, after carbon dioxide insufflation, before lung recruitment, after first highest PEEP, after second highest PEEP, after optimal PEEP, before and after volume expansion. Statistical analysis: within-patient change (Friedman, Wilcoxon signed rank), correlation (with cardiac output)	enrollment phase (up to 2 years)
Change in secondary hemodynamic and ventilatory variables in response to cardiorespiratory changes and volume expansion during lung resection surgery	Hemodynamic variables (CO, SV, MAP, HR, dP/dt, Eadyn, PI, BIS, carotid diameter, resistivity index) are obtained from pulse contour analysis/ Doppler and respiratory variables (EtCO2, Ppeak, PEEP, TV, SpO2, FiO2, RR) are obtained from mechanical ventilator continuously during the same timepoints as primary variable. Outcome measure: all variables will be taken and reported at the following timepoints: awake (seated), awake (supine), after intubation, after lateral decubitus position, after transition to one-lung ventilation, after pleura opening, after carbon dioxide insufflation, before lung recruitment, after first highest PEEP, after second highest PEEP, after optimal PEEP, before and after volume expansion. Statistical analysis: within-patient change (Friedman, Wilcoxon signed rank), correlation	enrollment phase (up to 2 years)
Comparative between-group analysis of primary and secondary variables in patients of different sex, ventilation protocol, operative side, recruitment tolerance and fluid response.	Hemodynamic (CO, SV, MAP, HR, dP/dt, Eadyn, PI, BIS, carotid diameter, resistivity index) are obtained from pulse contour analysis/ Doppler and respiratory variables (EtCO2, Ppeak, PEEP, TV, SpO2, FiO2, RR) will be collected at following timepoints: awake (seated), awake (supine), after intubation, after lateral decubitus position, after transition to one-lung ventilation, after pleura opening, after carbon dioxide insufflation, before lung recruitment, after first highest PEEP, after second highest PEEP, after optimal PEEP, before and after volume expansion. Comparative between-group analysis of variables response will be performed. Groups are stratified by sex, ventilation protocol, operative side, recruitment tolerance and fluid response. Statistical analysis: between-patient change (Mann-Whitney).	enrollment phase (up to 2 years)

Collaborators and Investigators

• Sponsor: University of Valencia
• Collaborators: Hospital General Valencia

Study record dates

Study Major Dates

• Study Start (Actual): January 27, 2025
• Primary Completion (Estimated): December 17, 2026
• Study Completion (Estimated): March 15, 2027

Study Registration Dates

• First Submitted: June 30, 2026
• First Submitted That Met QC Criteria: September 1, 2026
• First Posted (Actual): September 9, 2026

Study Record Updates

• Last Update Posted (Actual): September 9, 2026
• Last Update Submitted That Met QC Criteria: September 1, 2026
• Last Verified: September 1, 2026

More Information

Terms related to this study

• Keywords: hemodynamic instability; carotid, cerebral circulation
• Other Study ID Numbers: Registro:24/2023

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No