Acute Preoperative Stress and Hypotension After Spinal Anesthesia. SAS for Salivary Amylase and Stress 

Study Overview
=================
Brief Summary
-----------------
Spinal anesthesia is the technique of choice for planned cesarean section. It is associated with a high frequency of maternal hypotension. Hyperactivity of the sympathetic system assessed with the LF/HF ratio (heart rate variability analysis) predicts the severity of maternal hypotension after spinal anesthesia. Increased LF/HF ratio may be explained by maternal stress that can be measured with salivary amylase. The goal of this study is to assess the relationship between salivary amylase and severity of maternal hypotension after spinal anesthesia for planned cesarean section.

Detailed Description
-----------------
Salivary amylase, heart rate variability, Spielberger state-trait inventory are assessed on the morning of surgery, on the surgical ward, and repeated in the operating room, before performing spinal anesthesia. Spinal anesthesia use hyperbaric bupivacaine (11 mg), sufentanil (5 µg) and morphine (100 µg). Prophylactic treatment of hypotension uses a continuous infusion of ephedrine (0.6 mg/ml) and phenylephrine (10 µg/ml). Rate of the continuous infusion is adapted to keep maternal systolic blood pressure between 95-105% of preinduction values. Total dose of ephedrine and phenylephrine infused from spinal anesthesia to delivery of the newborn is recorded (about 20 minutes for the estimated time frame). Association between stress markers and total dose of vasoactive drugs will be tested with the Spearman's correlation coefficient. The study is observational. The subjects do receive a therapeutic intervention but the investigator does not assign patients to this intervention since this intervention is a routine care (spinal anesthesia for planned cesarian section) that would have been performed in the absence of the study.

Official Title
-----------------
Effect of Acute Preoperative Stress Assessed With Salivary Amylase on the Severity of Maternal Hypotension After Spinal Anesthesia for Planned Cesarean Section

Conditions
-----------------
Planned Cesarean Section

Participation Criteria
=================
Eligibility Criteria
-----------------
Pregnant women undergoing planned cesarean section under spinal anesthesia

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 50 Years

Sexes Eligible for Study
-----------------
Female

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| SAS cohort<br>Consecutive patients undergoing planned cesarean section under spinal anesthesia | |

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Severity of maternal hypotension assessed with the total dose of vasoactive drugs required to keep systolic blood pressure between 95-105% of preinduction values. |  | 20 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Salivary amylase activity | Measurement of amylase activity on a sample performed in the operating room, immediately before spinal anesthesia | 20 minutes | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Stress, Anxiety, Cesarean Section, Spinal anesthesia, Hypotension