Investigating Maternal Effects of Positions Applied in Patients Preparing for Caesarean Section Under Spinal Anesthesia (cs position)

After the approval of the Ethics Committee, 120 patients were planned to be included in the study between 15.06.2022 and 15.01.2023. Women who underwent elective cesarean delivery under spinal anesthesia were randomized to the supine position, 15° left-lateral tilt position, or 30° left-lateral tilt position. The position will be changed to supine before the incision. It was planned to recruit 40 patients from each group, with a total of 120 patients. Anesthetic management was standardized and fluid administration with 10 mL/kg isotonic was planned. Hypotension (systolic blood pressure [SBP] reduction > 20% baseline or SBP <90 mm Hg) will be treated with intravenous bolus ephedrine based on maternal heart rate. The primary outcome is planned to include maternal SBP in 15 minutes of anesthesia induction, the amount of vasoactive drug administered before the end of surgery, and the incidence of hypotension during cesarean delivery.

Study Overview

• Status: Enrolling by invitation
• Conditions: Hypotension
• Intervention / Treatment: Other: position

Detailed Description

Pregnant women in the supine position may compress the Inferior Vena Cava (IVC) by compression of the enlarged uterus in the third trimester. In this way, it is considered that it may reduce the amount of returning blood and cause hypotension. The incidence of this condition, called Supine Hypotension Syndrome, was reported to be 8%-10% (1-3). Spinal anesthesia, decreased sympathetic tonus, decreased systemic vascular resistance, and vasodilation may also cause hypotension in the patient (4).

It was considered that if the uterus is tilted, the pressure on the IVC would be removed, increasing the return, blood volume and cardiac output, improving the fetus, blood supply and oxygen supply (5). However, studies that were conducted so far have not proven significant differences and there is no routine standard practice (6-8). Here, the purpose was to investigate the maternal effects between supine, tilt to the left of 15-degree, and tilt to the left of 30-degree., References

1. Howard BK, Goodson JH, Mengert WF. Supine hypotensive syndrome in late pregnancy. Obstet Gynecol. 1953;1:371-377.
2. Kinsella SM, Lohmann G. Supine hypotensive syndrome. Obstet Gynecol. 1994;83:774-788.
3. Rees GA, Willis BA. Resuscitation in late pregnancy. Anaesthesia. 1988;43:347-349.
4. Dyer RA, Reed AR, van Dyk D, et al. Hemodynamic effects of ephedrine, phenylephrine, and the coadministration of phenylephrine with oxytocin during spinal anesthesia for elective cesarean delivery. Anesthesiology. 2009;111:753-765.
5. Kinsella SM. Lateral tilt for pregnant women: why 15-degree? Anaesthesia. 2003;58:835-836.
6. Ellington C, Katz VL, Watson WJ, Spielman FJ. The effect of lateral tilt on maternal and fetal hemodynamic variables. Obstet Gynecol. 1991;77:201-203.

7. Bamber JH, Dresner M. Aortocaval compression in pregnancy: the effect of changing the degree and direction of lateral tilt on maternal cardiac output. Anesth Analg.

   2003;97:256-258.

8. Calvache JA, Mu.oz MF, Baron FJ. Hemodynamic effects of a right lumbar-pelvic wedge during spinal anesthesia for cesarean section. Int J Obstet Anesth. 2011;20:307-311.

• Study Type: Observational
• Enrollment (Anticipated): 1

Contacts and Locations

Study Locations

• Turkey
  • Aydin, Turkey
    • Aydin Maternity and Child Health Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 14 years to 31 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Female

• Sampling Method: Non-Probability Sample

Study Population

Women who underwent elective cesarean delivery under spinal anesthesia

Description

Inclusion Criteria:

• Elective cesarean delivery with term pregnancy
• Patient's height 150-180 cm
• American Society of Anesthesiologists (ASA) Physical Condition II
• Body Mass Index (BMI) <35 kg/m2.

Exclusion Criteria:

• Fetal macrosomia
• Uterine abnormalities (e.g. large fibroids, bicornuate uterus)
• Polyhydramnios
• Torn membranes, oligohydramnios
• Intrauterine growth restriction
• Gestational or non-gestational hypertension, diabetes, or eclampsia
• Contraindications for spinal anesthesia

Study Plan

How is the study designed?

Design Details

• Observational Models: Case-Control
• Time Perspectives: Prospective

Number of groups / cohorts

3

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Supine; supine	Other: position; To compare whether there is a difference between maternal and fetal effects of Supine, 15-degree left tilt, and 30-degrees left tilt.
15° left-lateral tilt position; 15° left-lateral tilt position.	Other: position; To compare whether there is a difference between maternal and fetal effects of Supine, 15-degree left tilt, and 30-degrees left tilt.
30° left-lateral tilt position.	Other: position; To compare whether there is a difference between maternal and fetal effects of Supine, 15-degree left tilt, and 30-degrees left tilt.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
position	the purpose was to investigate the maternal effects between supine, tilt to the left of 15-degree, and tilt to the left of 30-degree.	through study completion, an average of 6 months

Collaborators and Investigators

• Sponsor: Aydin Maternity and Child Health Hospital
• Investigators: Principal Investigator: FERDİ GÜLAŞTI, Aydin Maternity and Child Health Hospital

Publications and helpful links

General Publications

• Liu T, Zou S, Guo L, Niu Z, Wang M, Xu C, Gao X, Shi Z, Guo X, Xiao H, Qi D. Effect of Different Positions During Surgical Preparation With Combined Spinal-Epidural Anesthesia for Elective Cesarean Delivery: A Randomized Controlled Trial. Anesth Analg. 2021 Nov 1;133(5):1235-1243. doi: 10.1213/ANE.0000000000005320.

Study record dates

Study Major Dates

• Study Start (Actual): June 15, 2022
• Primary Completion (Anticipated): January 15, 2023
• Study Completion (Anticipated): January 15, 2023

Study Registration Dates

• First Submitted: October 20, 2022
• First Submitted That Met QC Criteria: October 24, 2022
• First Posted (Actual): October 27, 2022

Study Record Updates

• Last Update Posted (Actual): October 27, 2022
• Last Update Submitted That Met QC Criteria: October 24, 2022
• Last Verified: October 1, 2022

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Hypotension
• Other Study ID Numbers: 2022-10

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