Cesarean Anesthesia Blood Gas

October 6, 2026 updated by: ali kahvecioğlu, Bagcilar Training and Research Hospital

Effects of Spinal and General Anesthesia Techniques on Maternal-Fetal Blood Gas Gradients and Fetal Carboxyhemoglobin Levels in Cesarean Delivery: A Prospective Observational Cohort Study

This prospective observational cohort study will evaluate maternal and fetal blood gas parameters in women undergoing cesarean delivery under spinal or general anesthesia. Maternal venous blood samples will be obtained immediately before anesthesia induction, and umbilical arterial blood samples will be obtained after delivery and cord clamping. Blood gas parameters, including pH, pCO2, pO2, bicarbonate, base excess, lactate, and fetal carboxyhemoglobin levels, will be compared between the spinal and general anesthesia groups. The study will also evaluate maternal-fetal blood gas gradients, Apgar scores, neonatal intensive care requirements, and the relationship between smoking exposure and fetal carboxyhemoglobin levels.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Observational

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
134

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Locations

  • Turkey (Türkiye)
    • Istanbul
      • Istanbul, Istanbul, Turkey (Türkiye), 59050
        • Recruiting
        • Bağcılar Training and Research Hospital
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

Female

Sampling Method

Non-Probability Sample

Study Population

Pregnant women undergoing cesarean delivery at the Obstetrics and Gynecology Clinic of Bagcilar Training and Research Hospital. The study is a prospective observational cohort comparing maternal and fetal blood gas parameters and fetal carboxyhemoglobin levels according to the observed anesthesia technique (spinal or general anesthesia).

Description

Inclusion Criteria:

  • Adult women undergoing cesarean delivery at the study center.
  • Patients receiving spinal or general anesthesia for cesarean delivery.

Exclusion Criteria:

  • Patients who are not eligible for participation according to the study protocol.
  • Patients in whom spinal anesthesia is converted to general anesthesia because of inadequate spinal block and pain during surgery.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Observational Models: COHORT
  • Time Perspectives: PROSPECTIVE

Cohorts and Interventions

Group / Cohort

Group / Cohort

A group or subgroup of participants in an observational study that is assessed for biomedical or health outcomes.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Spinal Anesthesia

Participants undergoing cesarean delivery who receive spinal anesthesia as the anesthesia technique.
Other: Anesthesia Technique

Observed anesthesia technique in women undergoing cesarean delivery. Participants received either spinal anesthesia or general anesthesia as part of routine clinical care; the anesthesia technique was not assigned by the study.
General Anesthesia

Participants undergoing cesarean delivery who receive general anesthesia as the anesthesia technique.
Other: Anesthesia Technique

Observed anesthesia technique in women undergoing cesarean delivery. Participants received either spinal anesthesia or general anesthesia as part of routine clinical care; the anesthesia technique was not assigned by the study.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Umbilical artery pH
Time Frame: Immediately after delivery

Umbilical arterial pH measured after delivery and cord clamping.
Immediately after delivery

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Maternal venous pH
Time Frame: Immediately before anesthesia induction

Maternal venous pH measured immediately before anesthesia induction.
Immediately before anesthesia induction
Umbilical artery pCO2
Time Frame: Immediately after delivery

Umbilical arterial pCO2 measured after delivery and cord clamping.
Immediately after delivery
Umbilical artery pO2
Time Frame: Immediately after delivery

Umbilical arterial pO2 measured after delivery and cord clamping.
Immediately after delivery
Maternal venous pCO2
Time Frame: Immediately before anesthesia induction

Maternal venous pCO2 measured immediately before anesthesia induction
Immediately before anesthesia induction
Maternal venous pO2
Time Frame: Immediately before anesthesia induction

Maternal venous pO2 measured immediately before anesthesia induction
Immediately before anesthesia induction
Umbilical artery HCO3
Time Frame: Immediately after delivery

Umbilical arterial bicarbonate measured after delivery and cord clamping.
Immediately after delivery
Maternal venous HCO3
Time Frame: Immediately before anesthesia induction

Maternal venous bicarbonate measured immediately before anesthesia induction
Immediately before anesthesia induction
Umbilical artery BE
Time Frame: Immediately after delivery

Umbilical arterial base excess measured after delivery and cord clamping
Immediately after delivery
Maternal venous BE
Time Frame: Immediately before anesthesia induction

Maternal venous base excess measured immediately before anesthesia induction
Immediately before anesthesia induction
Umbilical artery lactate
Time Frame: Immediately after delivery

Umbilical arterial lactate measured after delivery and cord clamping
Immediately after delivery
Maternal venous lactate
Time Frame: Immediately before anesthesia induction

Maternal venous lactate measured immediately before anesthesia induction
Immediately before anesthesia induction
Umbilical artery FCOHb
Time Frame: Immediately after delivery

Fetal carboxyhemoglobin measured in umbilical arterial blood after delivery and cord clamping
Immediately after delivery
Maternal venous FCOHb
Time Frame: Immediately before anesthesia induction

Maternal carboxyhemoglobin measured in venous blood immediately before anesthesia induction
Immediately before anesthesia induction
Maternal-fetal pH gradient (ΔpH)
Time Frame: Immediately after delivery

Difference between maternal venous pH and umbilical arterial pH
Immediately after delivery
Maternal-fetal pCO2 gradient (ΔpCO2)
Time Frame: Immediately after delivery

Difference between maternal venous pCO2 and umbilical arterial pCO2
Immediately after delivery
Maternal-fetal lactate gradient (Δlactate)
Time Frame: Immediately after delivery

Difference between maternal venous lactate and umbilical arterial lactate
Immediately after delivery
Apgar score at 1 minute
Time Frame: 1 minute after birth

Apgar score assessed 1 minute after birth using the Apgar score (range, 0-10), with higher scores indicating better neonatal condition.
1 minute after birth
Apgar score at 5 minutes
Time Frame: 5 minutes after birth

Apgar score assessed 5 minutes after birth using the Apgar score (range, 0-10), with higher scores indicating better neonatal condition.
5 minutes after birth
Neonatal intensive care unit admission
Time Frame: During the immediate neonatal period

Requirement for admission to the neonatal intensive care unit after birth
During the immediate neonatal period
Neonatal intubation
Time Frame: During the immediate neonatal period

Requirement for endotracheal intubation after birth
During the immediate neonatal period
Maternal hypotension requiring treatment
Time Frame: From anesthesia induction until the end of surgery

Occurrence of maternal hypotension requiring pharmacologic treatment during cesarean delivery
From anesthesia induction until the end of surgery
Maternal vasopressor requirement
Time Frame: From anesthesia induction until the end of surgery

Requirement for vasopressor administration for management of maternal hypotension during cesarean delivery
From anesthesia induction until the end of surgery
Smoking exposure and fetal FCOHb
Time Frame: Immediately after delivery

Association between maternal smoking exposure status and fetal carboxyhemoglobin level measured in umbilical arterial blood
Immediately after delivery

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Bagcilar Training and Research Hospital

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Ali KAHVECİOĞLU, MD, University of Health Sciences, Bağcılar Training and Research Hospital

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
October 1, 2026

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
December 31, 2026

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
December 31, 2026

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
September 28, 2026

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
October 1, 2026

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
October 6, 2026

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
October 8, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
October 6, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
October 1, 2026

More Information

Terms related to this study

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • E-10840098-50.04-4657

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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