Evaluating abdominal size as a predictor for epidural space distance in obese patients

Evaluation of Sagittal Abdominal Diameter as a Predictor of the Skin to Epidural Space Distance in Obese Patients

Ain Shams University · NCT04095117

This study is testing if measuring the size of the abdomen can better predict how far the skin is from the epidural space in obese patients who need epidural anesthesia for surgery.

Quick facts

Study typeObservational
Enrollment135 (estimated)
Ages18 Years and up
SexAll
SponsorAin Shams University (other)
Locations2 sites (Cairo and 1 other locations)
Trial IDNCT04095117 on ClinicalTrials.gov

What this trial studies

This observational study aims to assess the sagittal abdominal diameter (SAD) as a predictor of the distance from the skin to the epidural space in obese patients, comparing its accuracy to that of body mass index (BMI). Adult patients with a BMI between 30 and 39.9 kg/m², scheduled for lower abdominal or lower extremity surgeries under epidural anesthesia, will be included. The SAD will be measured at the L4-5 level, and the epidural space will be accessed using a Tuohy needle with a loss of resistance technique. Successful placement will be confirmed through characteristic pressure wave changes.

Who should consider this trial

Good fit: Ideal candidates are adults aged 18 and older with a BMI between 30 and 39.9 who are undergoing elective lower extremity surgeries requiring epidural anesthesia.

Not a fit: Patients who are pregnant or have contraindications to epidural block will not benefit from this study.

Why it matters

Potential benefit: If successful, this study could improve the accuracy of epidural anesthesia placement in obese patients, enhancing surgical outcomes and patient safety.

How similar studies have performed: While the approach of using SAD as a predictor is less common, studies have shown that alternative predictors like BMI can be effective, suggesting potential for success with this novel method.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Age 18 years or older
* BMI 30 to 39.9
* Either sex
* Elective surgery on lower extremities performed under epidural anesthesia

Exclusion Criteria:

* Pregnant women
* Contraindications to epidural block

Where this trial is running

Cairo and 1 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.

View on ClinicalTrials.gov →

Conditions: Obesity, Epidural, Anesthesia, Headache

Last reviewed 2026-05-15 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.