Sancaktepe Sehit Prof. Dr. Ilhan Varank Training and Research Hospital
Istanbul, 34000, Turkey (Türkiye)
Location status: Recruiting
Recruiting
NCT Number: NCT07823569
Effect of Prone Position on Continuous Noninvasive Hemoglobin Measurement
This prospective observational study aims to evaluate whether the prone position affects the agreement between noninvasive hemoglobin (SpHb) measurements and laboratory hemoglobin values in patients undergoing lumbar stabilization surgery under general anesthesia.
SpHb provides continuous, noninvasive monitoring of hemoglobin using multi-wavelength pulse CO-oximetry. However, its accuracy may be affected by changes in peripheral perfusion, hemodynamic status, and patient position. The prone position used during spine surgery may alter cardiovascular function and peripheral perfusion and may therefore influence SpHb measurements.
In this study, SpHb values obtained in the supine and prone positions will be compared with simultaneously obtained laboratory hemoglobin values. The study will also evaluate the ability of SpHb to follow changes in hemoglobin during surgery. The results may help clarify the clinical usefulness of continuous noninvasive hemoglobin monitoring during surgery performed in the prone position.
Recruiting
Interested in participating?
Request InfoKey information
Age range
18 year and older
Sex eligibility
All sexes
Study type
Observational
Primary location
About this study
This is a prospective, single-center observational study involving adult patients undergoing lumbar stabilization surgery under general anesthesia. Eligible patients will be older than 18 years and classified as American Society of Anesthesiologists (ASA) physical status I-III.
During surgery, noninvasive hemoglobin concentration (SpHb) will be monitored using a pulse CO-oximetry sensor placed on the finger as part of intraoperative monitoring. SpHb measurements will be compared with laboratory hemoglobin values obtained from blood gas analysis. Measurements obtained during supine and prone positioning will be evaluated to determine whether prone positioning affects the agreement between noninvasive and laboratory hemoglobin measurements.
Demographic and clinical characteristics, intraoperative hemodynamic variables, laboratory and blood gas parameters, estimated intraoperative blood loss, amount of transfused blood products, postoperative intensive care unit stay, and total hospital length of stay will also be recorded. The study will additionally assess the potential of SpHb for following intraoperative hemoglobin trends.
Who can participate
Healthy volunteers accepted: No
Only the study team can determine whether someone qualifies for participation.
Inclusion criteria
- Age 18 years or older
- American Society of Anesthesiologists (ASA) physical status I-III
- Scheduled to undergo lumbar stabilization surgery under general anesthesia
- Provision of written informed consent for participation in the study
Exclusion criteria
- Refusal to participate in the study
- ASA physical status IV-V
- Hemoglobin level <10 g/dL
- Presence of peripheral arterial disease
Treatment and study plan
Prone Positioning
OtherProne positioning is performed as part of standard surgical care for lumbar stabilization surgery and is not assigned by the investigators. The study will evaluate the association between prone positioning and the agreement between noninvasive hemoglobin (SpHb) measurements and simultaneously obtained laboratory hemoglobin values.
Primary outcomes
-
Agreement Between Noninvasive Hemoglobin (SpHb) and Laboratory Hemoglobin Measurements
Time frame: Intraoperative period, during supine and prone positioning on the day of surgery
Paired noninvasive hemoglobin (SpHb) and laboratory hemoglobin values will be obtained at corresponding intraoperative time points in the supine and prone positions. The primary outcome is the agreement between SpHb and laboratory hemoglobin measurements and whether this agreement changes after positioning the patient prone.
Secondary outcomes
-
Ability of SpHb to Track Intraoperative Hemoglobin Changes
Time frame: Intraoperative period on the day of surgery
Changes in noninvasive hemoglobin (SpHb) measurements over the intraoperative period will be compared with corresponding changes in laboratory hemoglobin values to evaluate the ability of SpHb to track the direction and magnitude of hemoglobin changes during surgery.
Study contacts
Contact information is provided by the study sponsor or research team.
Sponsors and collaborators
Lead sponsor
Sehit Prof. Dr. Ilhan Varank Sancaktepe Training and Research Hospital
Other
Registry information
Official study title
Does the Prone Position Affect Continuous Noninvasive Hemoglobin Measurement?
Important dates
- Study start
- 2026
- Primary completion
- 2026
- Study completion
- 2026
- First posted
- Sep 16, 2026
- Registry last updated
- Sep 16, 2026
OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.
View the official ClinicalTrials.gov record (opens in a new tab)This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.
Related clinical trials
Published trials that share one or more normalized conditions with this study.
Not yet recruiting
ESP Block Vs. QIPB for Lumbar Stabilization Surgery
NCT07789509
Agnosia, Erector Spina Plan Block
View Trial Details