Determination of Utility of Intergluteal Cleft as Landmark for Neuraxial Midline in Obstetrics

Study Overview
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Brief Summary
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Our aim is to investigate whether a novel landmark, the groove between the buttocks or the intergluteal cleft, can facilitate the identification of the neuraxial midline in obstetric patients when compared to ultrasound as the reference standard for the determination of this midline

Detailed Description
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Determine if the intergluteal cleft, when compared to ultrasound as the reference standard, can be used to identify the neuraxial midline in obstetric patients Difference in horizontal distance between the vertical lines of the intergluteal cleft and the neuraxial midline, the latter measured with ultrasound

Official Title
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Determination of the Utility of the Intergluteal Cleft as a Landmark for nEuraxial Midline identiFication in obsteTric Patients

Conditions
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Obstetric Anesthesia Problems

Intervention / Treatment
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* Diagnostic Test: Intergluteal Cleft
* Diagnostic Test: Neuraxial Midline
* Diagnostic Test: Horizontal Distance between Vertical Markings


Participation Criteria
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Eligibility Criteria
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Inclusion criteria Female 18 years of age or older Gestation of 37 weeks or above Exclusion criteria Acute or chronic confusional state Allergy to ultrasound gel Positive for COVID-19 and/or presence of symptoms consistent with SARS-Cov-2, such as anosmia, cough or fever History of previous surgery to the spine Scoliosis Unable to speak and/or understand English

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Study Group<br>Each patient will be requested to adopt a standardised upright position. First, two of the investigators will use a spirit level ruler and ink pen to agree upon and visibly mark the horizontal intercristal line on the back of the patient. Second, investigator B will leave the room, and investigator A will make a vertical mark with an ultraviolet pen denoting the intersection of the inferior aspect of the intergluteal cleft and the horizontal intercristal line. Third, investigator A will then leave the room, and investigator B will return to the room to make a vertical mark with an ink pen representing the intersection of the neuraxial midline, as established with the transverse spinous process view on ultrasound, and the horizontal intercristal line. After these two vertical marks have been made at the level of the intercristal line, the horizontal distance between them will be measured in mm by these same two investigators | Diagnostic Test: Intergluteal Cleft<br>* Marking of intersection between inferior aspect of the intergluteal cleft and the horizontal intercristal line<br>Diagnostic Test: Neuraxial Midline<br>* Marking of intersection between the neuraxial midline, as established with the transverse spinous process view on ultrasound, and the horizontal intercristal line<br>Diagnostic Test: Horizontal Distance between Vertical Markings<br>* The horizontal distance between these two vertical marks will be measured at the level of the intercristal line<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Horizontal distance between intergluteal cleft and neuraxial midline | One horizontal distance and hence one primary outcome | 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Difference in horizontal distance stratified by body mass index | Variation for BMI and recorded data | 12 months | 
| Difference in horizontal distance stratified by presence of pre-eclampsia | Variation for pre-ecalmpsia and recorded data | 12 months | 
| Difference in horizontal distance stratified by presence of pregnancy induced hypertension | Variation for pregnancy induced hypertension a and recorded data | 12 months |